// Copyright 2023 Google LLC
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//     https://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

// Code generated by protoc-gen-go_gapic. DO NOT EDIT.

package compute

import (
	"bytes"
	"context"
	"fmt"
	"io/ioutil"
	"math"
	"net/http"
	"net/url"
	"sort"

	computepb "cloud.google.com/go/compute/apiv1/computepb"
	gax "github.com/googleapis/gax-go/v2"
	"google.golang.org/api/googleapi"
	"google.golang.org/api/iterator"
	"google.golang.org/api/option"
	"google.golang.org/api/option/internaloption"
	httptransport "google.golang.org/api/transport/http"
	"google.golang.org/grpc"
	"google.golang.org/grpc/metadata"
	"google.golang.org/protobuf/encoding/protojson"
	"google.golang.org/protobuf/proto"
)

var newInstanceGroupManagersClientHook clientHook

// InstanceGroupManagersCallOptions contains the retry settings for each method of InstanceGroupManagersClient.
type InstanceGroupManagersCallOptions struct {
	AbandonInstances         []gax.CallOption
	AggregatedList           []gax.CallOption
	ApplyUpdatesToInstances  []gax.CallOption
	CreateInstances          []gax.CallOption
	Delete                   []gax.CallOption
	DeleteInstances          []gax.CallOption
	DeletePerInstanceConfigs []gax.CallOption
	Get                      []gax.CallOption
	Insert                   []gax.CallOption
	List                     []gax.CallOption
	ListErrors               []gax.CallOption
	ListManagedInstances     []gax.CallOption
	ListPerInstanceConfigs   []gax.CallOption
	Patch                    []gax.CallOption
	PatchPerInstanceConfigs  []gax.CallOption
	RecreateInstances        []gax.CallOption
	Resize                   []gax.CallOption
	SetInstanceTemplate      []gax.CallOption
	SetTargetPools           []gax.CallOption
	UpdatePerInstanceConfigs []gax.CallOption
}

func defaultInstanceGroupManagersRESTCallOptions() *InstanceGroupManagersCallOptions {
	return &InstanceGroupManagersCallOptions{
		AbandonInstances:         []gax.CallOption{},
		AggregatedList:           []gax.CallOption{},
		ApplyUpdatesToInstances:  []gax.CallOption{},
		CreateInstances:          []gax.CallOption{},
		Delete:                   []gax.CallOption{},
		DeleteInstances:          []gax.CallOption{},
		DeletePerInstanceConfigs: []gax.CallOption{},
		Get:                      []gax.CallOption{},
		Insert:                   []gax.CallOption{},
		List:                     []gax.CallOption{},
		ListErrors:               []gax.CallOption{},
		ListManagedInstances:     []gax.CallOption{},
		ListPerInstanceConfigs:   []gax.CallOption{},
		Patch:                    []gax.CallOption{},
		PatchPerInstanceConfigs:  []gax.CallOption{},
		RecreateInstances:        []gax.CallOption{},
		Resize:                   []gax.CallOption{},
		SetInstanceTemplate:      []gax.CallOption{},
		SetTargetPools:           []gax.CallOption{},
		UpdatePerInstanceConfigs: []gax.CallOption{},
	}
}

// internalInstanceGroupManagersClient is an interface that defines the methods available from Google Compute Engine API.
type internalInstanceGroupManagersClient interface {
	Close() error
	setGoogleClientInfo(...string)
	Connection() *grpc.ClientConn
	AbandonInstances(context.Context, *computepb.AbandonInstancesInstanceGroupManagerRequest, ...gax.CallOption) (*Operation, error)
	AggregatedList(context.Context, *computepb.AggregatedListInstanceGroupManagersRequest, ...gax.CallOption) *InstanceGroupManagersScopedListPairIterator
	ApplyUpdatesToInstances(context.Context, *computepb.ApplyUpdatesToInstancesInstanceGroupManagerRequest, ...gax.CallOption) (*Operation, error)
	CreateInstances(context.Context, *computepb.CreateInstancesInstanceGroupManagerRequest, ...gax.CallOption) (*Operation, error)
	Delete(context.Context, *computepb.DeleteInstanceGroupManagerRequest, ...gax.CallOption) (*Operation, error)
	DeleteInstances(context.Context, *computepb.DeleteInstancesInstanceGroupManagerRequest, ...gax.CallOption) (*Operation, error)
	DeletePerInstanceConfigs(context.Context, *computepb.DeletePerInstanceConfigsInstanceGroupManagerRequest, ...gax.CallOption) (*Operation, error)
	Get(context.Context, *computepb.GetInstanceGroupManagerRequest, ...gax.CallOption) (*computepb.InstanceGroupManager, error)
	Insert(context.Context, *computepb.InsertInstanceGroupManagerRequest, ...gax.CallOption) (*Operation, error)
	List(context.Context, *computepb.ListInstanceGroupManagersRequest, ...gax.CallOption) *InstanceGroupManagerIterator
	ListErrors(context.Context, *computepb.ListErrorsInstanceGroupManagersRequest, ...gax.CallOption) *InstanceManagedByIgmErrorIterator
	ListManagedInstances(context.Context, *computepb.ListManagedInstancesInstanceGroupManagersRequest, ...gax.CallOption) *ManagedInstanceIterator
	ListPerInstanceConfigs(context.Context, *computepb.ListPerInstanceConfigsInstanceGroupManagersRequest, ...gax.CallOption) *PerInstanceConfigIterator
	Patch(context.Context, *computepb.PatchInstanceGroupManagerRequest, ...gax.CallOption) (*Operation, error)
	PatchPerInstanceConfigs(context.Context, *computepb.PatchPerInstanceConfigsInstanceGroupManagerRequest, ...gax.CallOption) (*Operation, error)
	RecreateInstances(context.Context, *computepb.RecreateInstancesInstanceGroupManagerRequest, ...gax.CallOption) (*Operation, error)
	Resize(context.Context, *computepb.ResizeInstanceGroupManagerRequest, ...gax.CallOption) (*Operation, error)
	SetInstanceTemplate(context.Context, *computepb.SetInstanceTemplateInstanceGroupManagerRequest, ...gax.CallOption) (*Operation, error)
	SetTargetPools(context.Context, *computepb.SetTargetPoolsInstanceGroupManagerRequest, ...gax.CallOption) (*Operation, error)
	UpdatePerInstanceConfigs(context.Context, *computepb.UpdatePerInstanceConfigsInstanceGroupManagerRequest, ...gax.CallOption) (*Operation, error)
}

// InstanceGroupManagersClient is a client for interacting with Google Compute Engine API.
// Methods, except Close, may be called concurrently. However, fields must not be modified concurrently with method calls.
//
// The InstanceGroupManagers API.
type InstanceGroupManagersClient struct {
	// The internal transport-dependent client.
	internalClient internalInstanceGroupManagersClient

	// The call options for this service.
	CallOptions *InstanceGroupManagersCallOptions
}

// Wrapper methods routed to the internal client.

// Close closes the connection to the API service. The user should invoke this when
// the client is no longer required.
func (c *InstanceGroupManagersClient) Close() error {
	return c.internalClient.Close()
}

// setGoogleClientInfo sets the name and version of the application in
// the `x-goog-api-client` header passed on each request. Intended for
// use by Google-written clients.
func (c *InstanceGroupManagersClient) setGoogleClientInfo(keyval ...string) {
	c.internalClient.setGoogleClientInfo(keyval...)
}

// Connection returns a connection to the API service.
//
// Deprecated: Connections are now pooled so this method does not always
// return the same resource.
func (c *InstanceGroupManagersClient) Connection() *grpc.ClientConn {
	return c.internalClient.Connection()
}

// AbandonInstances flags the specified instances to be removed from the managed instance group. Abandoning an instance does not delete the instance, but it does remove the instance from any target pools that are applied by the managed instance group. This method reduces the targetSize of the managed instance group by the number of instances that you abandon. This operation is marked as DONE when the action is scheduled even if the instances have not yet been removed from the group. You must separately verify the status of the abandoning action with the listmanagedinstances method. If the group is part of a backend service that has enabled connection draining, it can take up to 60 seconds after the connection draining duration has elapsed before the VM instance is removed or deleted. You can specify a maximum of 1000 instances with this method per request.
func (c *InstanceGroupManagersClient) AbandonInstances(ctx context.Context, req *computepb.AbandonInstancesInstanceGroupManagerRequest, opts ...gax.CallOption) (*Operation, error) {
	return c.internalClient.AbandonInstances(ctx, req, opts...)
}

// AggregatedList retrieves the list of managed instance groups and groups them by zone.
func (c *InstanceGroupManagersClient) AggregatedList(ctx context.Context, req *computepb.AggregatedListInstanceGroupManagersRequest, opts ...gax.CallOption) *InstanceGroupManagersScopedListPairIterator {
	return c.internalClient.AggregatedList(ctx, req, opts...)
}

// ApplyUpdatesToInstances applies changes to selected instances on the managed instance group. This method can be used to apply new overrides and/or new versions.
func (c *InstanceGroupManagersClient) ApplyUpdatesToInstances(ctx context.Context, req *computepb.ApplyUpdatesToInstancesInstanceGroupManagerRequest, opts ...gax.CallOption) (*Operation, error) {
	return c.internalClient.ApplyUpdatesToInstances(ctx, req, opts...)
}

// CreateInstances creates instances with per-instance configurations in this managed instance group. Instances are created using the current instance template. The create instances operation is marked DONE if the createInstances request is successful. The underlying actions take additional time. You must separately verify the status of the creating or actions with the listmanagedinstances method.
func (c *InstanceGroupManagersClient) CreateInstances(ctx context.Context, req *computepb.CreateInstancesInstanceGroupManagerRequest, opts ...gax.CallOption) (*Operation, error) {
	return c.internalClient.CreateInstances(ctx, req, opts...)
}

// Delete deletes the specified managed instance group and all of the instances in that group. Note that the instance group must not belong to a backend service. Read Deleting an instance group for more information.
func (c *InstanceGroupManagersClient) Delete(ctx context.Context, req *computepb.DeleteInstanceGroupManagerRequest, opts ...gax.CallOption) (*Operation, error) {
	return c.internalClient.Delete(ctx, req, opts...)
}

// DeleteInstances flags the specified instances in the managed instance group for immediate deletion. The instances are also removed from any target pools of which they were a member. This method reduces the targetSize of the managed instance group by the number of instances that you delete. This operation is marked as DONE when the action is scheduled even if the instances are still being deleted. You must separately verify the status of the deleting action with the listmanagedinstances method. If the group is part of a backend service that has enabled connection draining, it can take up to 60 seconds after the connection draining duration has elapsed before the VM instance is removed or deleted. You can specify a maximum of 1000 instances with this method per request.
func (c *InstanceGroupManagersClient) DeleteInstances(ctx context.Context, req *computepb.DeleteInstancesInstanceGroupManagerRequest, opts ...gax.CallOption) (*Operation, error) {
	return c.internalClient.DeleteInstances(ctx, req, opts...)
}

// DeletePerInstanceConfigs deletes selected per-instance configurations for the managed instance group.
func (c *InstanceGroupManagersClient) DeletePerInstanceConfigs(ctx context.Context, req *computepb.DeletePerInstanceConfigsInstanceGroupManagerRequest, opts ...gax.CallOption) (*Operation, error) {
	return c.internalClient.DeletePerInstanceConfigs(ctx, req, opts...)
}

// Get returns all of the details about the specified managed instance group.
func (c *InstanceGroupManagersClient) Get(ctx context.Context, req *computepb.GetInstanceGroupManagerRequest, opts ...gax.CallOption) (*computepb.InstanceGroupManager, error) {
	return c.internalClient.Get(ctx, req, opts...)
}

// Insert creates a managed instance group using the information that you specify in the request. After the group is created, instances in the group are created using the specified instance template. This operation is marked as DONE when the group is created even if the instances in the group have not yet been created. You must separately verify the status of the individual instances with the listmanagedinstances method. A managed instance group can have up to 1000 VM instances per group. Please contact Cloud Support if you need an increase in this limit.
func (c *InstanceGroupManagersClient) Insert(ctx context.Context, req *computepb.InsertInstanceGroupManagerRequest, opts ...gax.CallOption) (*Operation, error) {
	return c.internalClient.Insert(ctx, req, opts...)
}

// List retrieves a list of managed instance groups that are contained within the specified project and zone.
func (c *InstanceGroupManagersClient) List(ctx context.Context, req *computepb.ListInstanceGroupManagersRequest, opts ...gax.CallOption) *InstanceGroupManagerIterator {
	return c.internalClient.List(ctx, req, opts...)
}

// ListErrors lists all errors thrown by actions on instances for a given managed instance group. The filter and orderBy query parameters are not supported.
func (c *InstanceGroupManagersClient) ListErrors(ctx context.Context, req *computepb.ListErrorsInstanceGroupManagersRequest, opts ...gax.CallOption) *InstanceManagedByIgmErrorIterator {
	return c.internalClient.ListErrors(ctx, req, opts...)
}

// ListManagedInstances lists all of the instances in the managed instance group. Each instance in the list has a currentAction, which indicates the action that the managed instance group is performing on the instance. For example, if the group is still creating an instance, the currentAction is CREATING. If a previous action failed, the list displays the errors for that failed action. The orderBy query parameter is not supported. The pageToken query parameter is supported only in the alpha and beta API and only if the group’s listManagedInstancesResults field is set to PAGINATED.
func (c *InstanceGroupManagersClient) ListManagedInstances(ctx context.Context, req *computepb.ListManagedInstancesInstanceGroupManagersRequest, opts ...gax.CallOption) *ManagedInstanceIterator {
	return c.internalClient.ListManagedInstances(ctx, req, opts...)
}

// ListPerInstanceConfigs lists all of the per-instance configurations defined for the managed instance group. The orderBy query parameter is not supported.
func (c *InstanceGroupManagersClient) ListPerInstanceConfigs(ctx context.Context, req *computepb.ListPerInstanceConfigsInstanceGroupManagersRequest, opts ...gax.CallOption) *PerInstanceConfigIterator {
	return c.internalClient.ListPerInstanceConfigs(ctx, req, opts...)
}

// Patch updates a managed instance group using the information that you specify in the request. This operation is marked as DONE when the group is patched even if the instances in the group are still in the process of being patched. You must separately verify the status of the individual instances with the listManagedInstances method. This method supports PATCH semantics and uses the JSON merge patch format and processing rules. If you update your group to specify a new template or instance configuration, it’s possible that your intended specification for each VM in the group is different from the current state of that VM. To learn how to apply an updated configuration to the VMs in a MIG, see Updating instances in a MIG.
func (c *InstanceGroupManagersClient) Patch(ctx context.Context, req *computepb.PatchInstanceGroupManagerRequest, opts ...gax.CallOption) (*Operation, error) {
	return c.internalClient.Patch(ctx, req, opts...)
}

// PatchPerInstanceConfigs inserts or patches per-instance configurations for the managed instance group. perInstanceConfig.name (at http://perInstanceConfig.name) serves as a key used to distinguish whether to perform insert or patch.
func (c *InstanceGroupManagersClient) PatchPerInstanceConfigs(ctx context.Context, req *computepb.PatchPerInstanceConfigsInstanceGroupManagerRequest, opts ...gax.CallOption) (*Operation, error) {
	return c.internalClient.PatchPerInstanceConfigs(ctx, req, opts...)
}

// RecreateInstances flags the specified VM instances in the managed instance group to be immediately recreated. Each instance is recreated using the group’s current configuration. This operation is marked as DONE when the flag is set even if the instances have not yet been recreated. You must separately verify the status of each instance by checking its currentAction field; for more information, see Checking the status of managed instances. If the group is part of a backend service that has enabled connection draining, it can take up to 60 seconds after the connection draining duration has elapsed before the VM instance is removed or deleted. You can specify a maximum of 1000 instances with this method per request.
func (c *InstanceGroupManagersClient) RecreateInstances(ctx context.Context, req *computepb.RecreateInstancesInstanceGroupManagerRequest, opts ...gax.CallOption) (*Operation, error) {
	return c.internalClient.RecreateInstances(ctx, req, opts...)
}

// Resize resizes the managed instance group. If you increase the size, the group creates new instances using the current instance template. If you decrease the size, the group deletes instances. The resize operation is marked DONE when the resize actions are scheduled even if the group has not yet added or deleted any instances. You must separately verify the status of the creating or deleting actions with the listmanagedinstances method. When resizing down, the instance group arbitrarily chooses the order in which VMs are deleted. The group takes into account some VM attributes when making the selection including: + The status of the VM instance. + The health of the VM instance. + The instance template version the VM is based on. + For regional managed instance groups, the location of the VM instance. This list is subject to change. If the group is part of a backend service that has enabled connection draining, it can take up to 60 seconds after the connection draining duration has elapsed before the VM instance is removed or deleted.
func (c *InstanceGroupManagersClient) Resize(ctx context.Context, req *computepb.ResizeInstanceGroupManagerRequest, opts ...gax.CallOption) (*Operation, error) {
	return c.internalClient.Resize(ctx, req, opts...)
}

// SetInstanceTemplate specifies the instance template to use when creating new instances in this group. The templates for existing instances in the group do not change unless you run recreateInstances, run applyUpdatesToInstances, or set the group’s updatePolicy.type to PROACTIVE.
func (c *InstanceGroupManagersClient) SetInstanceTemplate(ctx context.Context, req *computepb.SetInstanceTemplateInstanceGroupManagerRequest, opts ...gax.CallOption) (*Operation, error) {
	return c.internalClient.SetInstanceTemplate(ctx, req, opts...)
}

// SetTargetPools modifies the target pools to which all instances in this managed instance group are assigned. The target pools automatically apply to all of the instances in the managed instance group. This operation is marked DONE when you make the request even if the instances have not yet been added to their target pools. The change might take some time to apply to all of the instances in the group depending on the size of the group.
func (c *InstanceGroupManagersClient) SetTargetPools(ctx context.Context, req *computepb.SetTargetPoolsInstanceGroupManagerRequest, opts ...gax.CallOption) (*Operation, error) {
	return c.internalClient.SetTargetPools(ctx, req, opts...)
}

// UpdatePerInstanceConfigs inserts or updates per-instance configurations for the managed instance group. perInstanceConfig.name (at http://perInstanceConfig.name) serves as a key used to distinguish whether to perform insert or patch.
func (c *InstanceGroupManagersClient) UpdatePerInstanceConfigs(ctx context.Context, req *computepb.UpdatePerInstanceConfigsInstanceGroupManagerRequest, opts ...gax.CallOption) (*Operation, error) {
	return c.internalClient.UpdatePerInstanceConfigs(ctx, req, opts...)
}

// Methods, except Close, may be called concurrently. However, fields must not be modified concurrently with method calls.
type instanceGroupManagersRESTClient struct {
	// The http endpoint to connect to.
	endpoint string

	// The http client.
	httpClient *http.Client

	// operationClient is used to call the operation-specific management service.
	operationClient *ZoneOperationsClient

	// The x-goog-* metadata to be sent with each request.
	xGoogMetadata metadata.MD

	// Points back to the CallOptions field of the containing InstanceGroupManagersClient
	CallOptions **InstanceGroupManagersCallOptions
}

// NewInstanceGroupManagersRESTClient creates a new instance group managers rest client.
//
// The InstanceGroupManagers API.
func NewInstanceGroupManagersRESTClient(ctx context.Context, opts ...option.ClientOption) (*InstanceGroupManagersClient, error) {
	clientOpts := append(defaultInstanceGroupManagersRESTClientOptions(), opts...)
	httpClient, endpoint, err := httptransport.NewClient(ctx, clientOpts...)
	if err != nil {
		return nil, err
	}

	callOpts := defaultInstanceGroupManagersRESTCallOptions()
	c := &instanceGroupManagersRESTClient{
		endpoint:    endpoint,
		httpClient:  httpClient,
		CallOptions: &callOpts,
	}
	c.setGoogleClientInfo()

	o := []option.ClientOption{
		option.WithHTTPClient(httpClient),
		option.WithEndpoint(endpoint),
	}
	opC, err := NewZoneOperationsRESTClient(ctx, o...)
	if err != nil {
		return nil, err
	}
	c.operationClient = opC

	return &InstanceGroupManagersClient{internalClient: c, CallOptions: callOpts}, nil
}

func defaultInstanceGroupManagersRESTClientOptions() []option.ClientOption {
	return []option.ClientOption{
		internaloption.WithDefaultEndpoint("https://compute.googleapis.com"),
		internaloption.WithDefaultMTLSEndpoint("https://compute.mtls.googleapis.com"),
		internaloption.WithDefaultAudience("https://compute.googleapis.com/"),
		internaloption.WithDefaultScopes(DefaultAuthScopes()...),
	}
}

// setGoogleClientInfo sets the name and version of the application in
// the `x-goog-api-client` header passed on each request. Intended for
// use by Google-written clients.
func (c *instanceGroupManagersRESTClient) setGoogleClientInfo(keyval ...string) {
	kv := append([]string{"gl-go", versionGo()}, keyval...)
	kv = append(kv, "gapic", getVersionClient(), "gax", gax.Version, "rest", "UNKNOWN")
	c.xGoogMetadata = metadata.Pairs("x-goog-api-client", gax.XGoogHeader(kv...))
}

// Close closes the connection to the API service. The user should invoke this when
// the client is no longer required.
func (c *instanceGroupManagersRESTClient) Close() error {
	// Replace httpClient with nil to force cleanup.
	c.httpClient = nil
	if err := c.operationClient.Close(); err != nil {
		return err
	}
	return nil
}

// Connection returns a connection to the API service.
//
// Deprecated: This method always returns nil.
func (c *instanceGroupManagersRESTClient) Connection() *grpc.ClientConn {
	return nil
}

// AbandonInstances flags the specified instances to be removed from the managed instance group. Abandoning an instance does not delete the instance, but it does remove the instance from any target pools that are applied by the managed instance group. This method reduces the targetSize of the managed instance group by the number of instances that you abandon. This operation is marked as DONE when the action is scheduled even if the instances have not yet been removed from the group. You must separately verify the status of the abandoning action with the listmanagedinstances method. If the group is part of a backend service that has enabled connection draining, it can take up to 60 seconds after the connection draining duration has elapsed before the VM instance is removed or deleted. You can specify a maximum of 1000 instances with this method per request.
func (c *instanceGroupManagersRESTClient) AbandonInstances(ctx context.Context, req *computepb.AbandonInstancesInstanceGroupManagerRequest, opts ...gax.CallOption) (*Operation, error) {
	m := protojson.MarshalOptions{AllowPartial: true}
	body := req.GetInstanceGroupManagersAbandonInstancesRequestResource()
	jsonReq, err := m.Marshal(body)
	if err != nil {
		return nil, err
	}

	baseUrl, err := url.Parse(c.endpoint)
	if err != nil {
		return nil, err
	}
	baseUrl.Path += fmt.Sprintf("/compute/v1/projects/%v/zones/%v/instanceGroupManagers/%v/abandonInstances", req.GetProject(), req.GetZone(), req.GetInstanceGroupManager())

	params := url.Values{}
	if req != nil && req.RequestId != nil {
		params.Add("requestId", fmt.Sprintf("%v", req.GetRequestId()))
	}

	baseUrl.RawQuery = params.Encode()

	// Build HTTP headers from client and context metadata.
	md := metadata.Pairs("x-goog-request-params", fmt.Sprintf("%s=%v&%s=%v&%s=%v", "project", url.QueryEscape(req.GetProject()), "zone", url.QueryEscape(req.GetZone()), "instance_group_manager", url.QueryEscape(req.GetInstanceGroupManager())))

	headers := buildHeaders(ctx, c.xGoogMetadata, md, metadata.Pairs("Content-Type", "application/json"))
	opts = append((*c.CallOptions).AbandonInstances[0:len((*c.CallOptions).AbandonInstances):len((*c.CallOptions).AbandonInstances)], opts...)
	unm := protojson.UnmarshalOptions{AllowPartial: true, DiscardUnknown: true}
	resp := &computepb.Operation{}
	e := gax.Invoke(ctx, func(ctx context.Context, settings gax.CallSettings) error {
		if settings.Path != "" {
			baseUrl.Path = settings.Path
		}
		httpReq, err := http.NewRequest("POST", baseUrl.String(), bytes.NewReader(jsonReq))
		if err != nil {
			return err
		}
		httpReq = httpReq.WithContext(ctx)
		httpReq.Header = headers

		httpRsp, err := c.httpClient.Do(httpReq)
		if err != nil {
			return err
		}
		defer httpRsp.Body.Close()

		if err = googleapi.CheckResponse(httpRsp); err != nil {
			return err
		}

		buf, err := ioutil.ReadAll(httpRsp.Body)
		if err != nil {
			return err
		}

		if err := unm.Unmarshal(buf, resp); err != nil {
			return maybeUnknownEnum(err)
		}

		return nil
	}, opts...)
	if e != nil {
		return nil, e
	}
	op := &Operation{
		&zoneOperationsHandle{
			c:       c.operationClient,
			proto:   resp,
			project: req.GetProject(),
			zone:    req.GetZone(),
		},
	}
	return op, nil
}

// AggregatedList retrieves the list of managed instance groups and groups them by zone.
func (c *instanceGroupManagersRESTClient) AggregatedList(ctx context.Context, req *computepb.AggregatedListInstanceGroupManagersRequest, opts ...gax.CallOption) *InstanceGroupManagersScopedListPairIterator {
	it := &InstanceGroupManagersScopedListPairIterator{}
	req = proto.Clone(req).(*computepb.AggregatedListInstanceGroupManagersRequest)
	unm := protojson.UnmarshalOptions{AllowPartial: true, DiscardUnknown: true}
	it.InternalFetch = func(pageSize int, pageToken string) ([]InstanceGroupManagersScopedListPair, string, error) {
		resp := &computepb.InstanceGroupManagerAggregatedList{}
		if pageToken != "" {
			req.PageToken = proto.String(pageToken)
		}
		if pageSize > math.MaxInt32 {
			req.MaxResults = proto.Uint32(math.MaxInt32)
		} else if pageSize != 0 {
			req.MaxResults = proto.Uint32(uint32(pageSize))
		}
		baseUrl, err := url.Parse(c.endpoint)
		if err != nil {
			return nil, "", err
		}
		baseUrl.Path += fmt.Sprintf("/compute/v1/projects/%v/aggregated/instanceGroupManagers", req.GetProject())

		params := url.Values{}
		if req != nil && req.Filter != nil {
			params.Add("filter", fmt.Sprintf("%v", req.GetFilter()))
		}
		if req != nil && req.IncludeAllScopes != nil {
			params.Add("includeAllScopes", fmt.Sprintf("%v", req.GetIncludeAllScopes()))
		}
		if req != nil && req.MaxResults != nil {
			params.Add("maxResults", fmt.Sprintf("%v", req.GetMaxResults()))
		}
		if req != nil && req.OrderBy != nil {
			params.Add("orderBy", fmt.Sprintf("%v", req.GetOrderBy()))
		}
		if req != nil && req.PageToken != nil {
			params.Add("pageToken", fmt.Sprintf("%v", req.GetPageToken()))
		}
		if req != nil && req.ReturnPartialSuccess != nil {
			params.Add("returnPartialSuccess", fmt.Sprintf("%v", req.GetReturnPartialSuccess()))
		}

		baseUrl.RawQuery = params.Encode()

		// Build HTTP headers from client and context metadata.
		headers := buildHeaders(ctx, c.xGoogMetadata, metadata.Pairs("Content-Type", "application/json"))
		e := gax.Invoke(ctx, func(ctx context.Context, settings gax.CallSettings) error {
			if settings.Path != "" {
				baseUrl.Path = settings.Path
			}
			httpReq, err := http.NewRequest("GET", baseUrl.String(), nil)
			if err != nil {
				return err
			}
			httpReq.Header = headers

			httpRsp, err := c.httpClient.Do(httpReq)
			if err != nil {
				return err
			}
			defer httpRsp.Body.Close()

			if err = googleapi.CheckResponse(httpRsp); err != nil {
				return err
			}

			buf, err := ioutil.ReadAll(httpRsp.Body)
			if err != nil {
				return err
			}

			if err := unm.Unmarshal(buf, resp); err != nil {
				return maybeUnknownEnum(err)
			}

			return nil
		}, opts...)
		if e != nil {
			return nil, "", e
		}
		it.Response = resp

		elems := make([]InstanceGroupManagersScopedListPair, 0, len(resp.GetItems()))
		for k, v := range resp.GetItems() {
			elems = append(elems, InstanceGroupManagersScopedListPair{k, v})
		}
		sort.Slice(elems, func(i, j int) bool { return elems[i].Key < elems[j].Key })

		return elems, resp.GetNextPageToken(), nil
	}

	fetch := func(pageSize int, pageToken string) (string, error) {
		items, nextPageToken, err := it.InternalFetch(pageSize, pageToken)
		if err != nil {
			return "", err
		}
		it.items = append(it.items, items...)
		return nextPageToken, nil
	}

	it.pageInfo, it.nextFunc = iterator.NewPageInfo(fetch, it.bufLen, it.takeBuf)
	it.pageInfo.MaxSize = int(req.GetMaxResults())
	it.pageInfo.Token = req.GetPageToken()

	return it
}

// ApplyUpdatesToInstances applies changes to selected instances on the managed instance group. This method can be used to apply new overrides and/or new versions.
func (c *instanceGroupManagersRESTClient) ApplyUpdatesToInstances(ctx context.Context, req *computepb.ApplyUpdatesToInstancesInstanceGroupManagerRequest, opts ...gax.CallOption) (*Operation, error) {
	m := protojson.MarshalOptions{AllowPartial: true}
	body := req.GetInstanceGroupManagersApplyUpdatesRequestResource()
	jsonReq, err := m.Marshal(body)
	if err != nil {
		return nil, err
	}

	baseUrl, err := url.Parse(c.endpoint)
	if err != nil {
		return nil, err
	}
	baseUrl.Path += fmt.Sprintf("/compute/v1/projects/%v/zones/%v/instanceGroupManagers/%v/applyUpdatesToInstances", req.GetProject(), req.GetZone(), req.GetInstanceGroupManager())

	// Build HTTP headers from client and context metadata.
	md := metadata.Pairs("x-goog-request-params", fmt.Sprintf("%s=%v&%s=%v&%s=%v", "project", url.QueryEscape(req.GetProject()), "zone", url.QueryEscape(req.GetZone()), "instance_group_manager", url.QueryEscape(req.GetInstanceGroupManager())))

	headers := buildHeaders(ctx, c.xGoogMetadata, md, metadata.Pairs("Content-Type", "application/json"))
	opts = append((*c.CallOptions).ApplyUpdatesToInstances[0:len((*c.CallOptions).ApplyUpdatesToInstances):len((*c.CallOptions).ApplyUpdatesToInstances)], opts...)
	unm := protojson.UnmarshalOptions{AllowPartial: true, DiscardUnknown: true}
	resp := &computepb.Operation{}
	e := gax.Invoke(ctx, func(ctx context.Context, settings gax.CallSettings) error {
		if settings.Path != "" {
			baseUrl.Path = settings.Path
		}
		httpReq, err := http.NewRequest("POST", baseUrl.String(), bytes.NewReader(jsonReq))
		if err != nil {
			return err
		}
		httpReq = httpReq.WithContext(ctx)
		httpReq.Header = headers

		httpRsp, err := c.httpClient.Do(httpReq)
		if err != nil {
			return err
		}
		defer httpRsp.Body.Close()

		if err = googleapi.CheckResponse(httpRsp); err != nil {
			return err
		}

		buf, err := ioutil.ReadAll(httpRsp.Body)
		if err != nil {
			return err
		}

		if err := unm.Unmarshal(buf, resp); err != nil {
			return maybeUnknownEnum(err)
		}

		return nil
	}, opts...)
	if e != nil {
		return nil, e
	}
	op := &Operation{
		&zoneOperationsHandle{
			c:       c.operationClient,
			proto:   resp,
			project: req.GetProject(),
			zone:    req.GetZone(),
		},
	}
	return op, nil
}

// CreateInstances creates instances with per-instance configurations in this managed instance group. Instances are created using the current instance template. The create instances operation is marked DONE if the createInstances request is successful. The underlying actions take additional time. You must separately verify the status of the creating or actions with the listmanagedinstances method.
func (c *instanceGroupManagersRESTClient) CreateInstances(ctx context.Context, req *computepb.CreateInstancesInstanceGroupManagerRequest, opts ...gax.CallOption) (*Operation, error) {
	m := protojson.MarshalOptions{AllowPartial: true}
	body := req.GetInstanceGroupManagersCreateInstancesRequestResource()
	jsonReq, err := m.Marshal(body)
	if err != nil {
		return nil, err
	}

	baseUrl, err := url.Parse(c.endpoint)
	if err != nil {
		return nil, err
	}
	baseUrl.Path += fmt.Sprintf("/compute/v1/projects/%v/zones/%v/instanceGroupManagers/%v/createInstances", req.GetProject(), req.GetZone(), req.GetInstanceGroupManager())

	params := url.Values{}
	if req != nil && req.RequestId != nil {
		params.Add("requestId", fmt.Sprintf("%v", req.GetRequestId()))
	}

	baseUrl.RawQuery = params.Encode()

	// Build HTTP headers from client and context metadata.
	md := metadata.Pairs("x-goog-request-params", fmt.Sprintf("%s=%v&%s=%v&%s=%v", "project", url.QueryEscape(req.GetProject()), "zone", url.QueryEscape(req.GetZone()), "instance_group_manager", url.QueryEscape(req.GetInstanceGroupManager())))

	headers := buildHeaders(ctx, c.xGoogMetadata, md, metadata.Pairs("Content-Type", "application/json"))
	opts = append((*c.CallOptions).CreateInstances[0:len((*c.CallOptions).CreateInstances):len((*c.CallOptions).CreateInstances)], opts...)
	unm := protojson.UnmarshalOptions{AllowPartial: true, DiscardUnknown: true}
	resp := &computepb.Operation{}
	e := gax.Invoke(ctx, func(ctx context.Context, settings gax.CallSettings) error {
		if settings.Path != "" {
			baseUrl.Path = settings.Path
		}
		httpReq, err := http.NewRequest("POST", baseUrl.String(), bytes.NewReader(jsonReq))
		if err != nil {
			return err
		}
		httpReq = httpReq.WithContext(ctx)
		httpReq.Header = headers

		httpRsp, err := c.httpClient.Do(httpReq)
		if err != nil {
			return err
		}
		defer httpRsp.Body.Close()

		if err = googleapi.CheckResponse(httpRsp); err != nil {
			return err
		}

		buf, err := ioutil.ReadAll(httpRsp.Body)
		if err != nil {
			return err
		}

		if err := unm.Unmarshal(buf, resp); err != nil {
			return maybeUnknownEnum(err)
		}

		return nil
	}, opts...)
	if e != nil {
		return nil, e
	}
	op := &Operation{
		&zoneOperationsHandle{
			c:       c.operationClient,
			proto:   resp,
			project: req.GetProject(),
			zone:    req.GetZone(),
		},
	}
	return op, nil
}

// Delete deletes the specified managed instance group and all of the instances in that group. Note that the instance group must not belong to a backend service. Read Deleting an instance group for more information.
func (c *instanceGroupManagersRESTClient) Delete(ctx context.Context, req *computepb.DeleteInstanceGroupManagerRequest, opts ...gax.CallOption) (*Operation, error) {
	baseUrl, err := url.Parse(c.endpoint)
	if err != nil {
		return nil, err
	}
	baseUrl.Path += fmt.Sprintf("/compute/v1/projects/%v/zones/%v/instanceGroupManagers/%v", req.GetProject(), req.GetZone(), req.GetInstanceGroupManager())

	params := url.Values{}
	if req != nil && req.RequestId != nil {
		params.Add("requestId", fmt.Sprintf("%v", req.GetRequestId()))
	}

	baseUrl.RawQuery = params.Encode()

	// Build HTTP headers from client and context metadata.
	md := metadata.Pairs("x-goog-request-params", fmt.Sprintf("%s=%v&%s=%v&%s=%v", "project", url.QueryEscape(req.GetProject()), "zone", url.QueryEscape(req.GetZone()), "instance_group_manager", url.QueryEscape(req.GetInstanceGroupManager())))

	headers := buildHeaders(ctx, c.xGoogMetadata, md, metadata.Pairs("Content-Type", "application/json"))
	opts = append((*c.CallOptions).Delete[0:len((*c.CallOptions).Delete):len((*c.CallOptions).Delete)], opts...)
	unm := protojson.UnmarshalOptions{AllowPartial: true, DiscardUnknown: true}
	resp := &computepb.Operation{}
	e := gax.Invoke(ctx, func(ctx context.Context, settings gax.CallSettings) error {
		if settings.Path != "" {
			baseUrl.Path = settings.Path
		}
		httpReq, err := http.NewRequest("DELETE", baseUrl.String(), nil)
		if err != nil {
			return err
		}
		httpReq = httpReq.WithContext(ctx)
		httpReq.Header = headers

		httpRsp, err := c.httpClient.Do(httpReq)
		if err != nil {
			return err
		}
		defer httpRsp.Body.Close()

		if err = googleapi.CheckResponse(httpRsp); err != nil {
			return err
		}

		buf, err := ioutil.ReadAll(httpRsp.Body)
		if err != nil {
			return err
		}

		if err := unm.Unmarshal(buf, resp); err != nil {
			return maybeUnknownEnum(err)
		}

		return nil
	}, opts...)
	if e != nil {
		return nil, e
	}
	op := &Operation{
		&zoneOperationsHandle{
			c:       c.operationClient,
			proto:   resp,
			project: req.GetProject(),
			zone:    req.GetZone(),
		},
	}
	return op, nil
}

// DeleteInstances flags the specified instances in the managed instance group for immediate deletion. The instances are also removed from any target pools of which they were a member. This method reduces the targetSize of the managed instance group by the number of instances that you delete. This operation is marked as DONE when the action is scheduled even if the instances are still being deleted. You must separately verify the status of the deleting action with the listmanagedinstances method. If the group is part of a backend service that has enabled connection draining, it can take up to 60 seconds after the connection draining duration has elapsed before the VM instance is removed or deleted. You can specify a maximum of 1000 instances with this method per request.
func (c *instanceGroupManagersRESTClient) DeleteInstances(ctx context.Context, req *computepb.DeleteInstancesInstanceGroupManagerRequest, opts ...gax.CallOption) (*Operation, error) {
	m := protojson.MarshalOptions{AllowPartial: true}
	body := req.GetInstanceGroupManagersDeleteInstancesRequestResource()
	jsonReq, err := m.Marshal(body)
	if err != nil {
		return nil, err
	}

	baseUrl, err := url.Parse(c.endpoint)
	if err != nil {
		return nil, err
	}
	baseUrl.Path += fmt.Sprintf("/compute/v1/projects/%v/zones/%v/instanceGroupManagers/%v/deleteInstances", req.GetProject(), req.GetZone(), req.GetInstanceGroupManager())

	params := url.Values{}
	if req != nil && req.RequestId != nil {
		params.Add("requestId", fmt.Sprintf("%v", req.GetRequestId()))
	}

	baseUrl.RawQuery = params.Encode()

	// Build HTTP headers from client and context metadata.
	md := metadata.Pairs("x-goog-request-params", fmt.Sprintf("%s=%v&%s=%v&%s=%v", "project", url.QueryEscape(req.GetProject()), "zone", url.QueryEscape(req.GetZone()), "instance_group_manager", url.QueryEscape(req.GetInstanceGroupManager())))

	headers := buildHeaders(ctx, c.xGoogMetadata, md, metadata.Pairs("Content-Type", "application/json"))
	opts = append((*c.CallOptions).DeleteInstances[0:len((*c.CallOptions).DeleteInstances):len((*c.CallOptions).DeleteInstances)], opts...)
	unm := protojson.UnmarshalOptions{AllowPartial: true, DiscardUnknown: true}
	resp := &computepb.Operation{}
	e := gax.Invoke(ctx, func(ctx context.Context, settings gax.CallSettings) error {
		if settings.Path != "" {
			baseUrl.Path = settings.Path
		}
		httpReq, err := http.NewRequest("POST", baseUrl.String(), bytes.NewReader(jsonReq))
		if err != nil {
			return err
		}
		httpReq = httpReq.WithContext(ctx)
		httpReq.Header = headers

		httpRsp, err := c.httpClient.Do(httpReq)
		if err != nil {
			return err
		}
		defer httpRsp.Body.Close()

		if err = googleapi.CheckResponse(httpRsp); err != nil {
			return err
		}

		buf, err := ioutil.ReadAll(httpRsp.Body)
		if err != nil {
			return err
		}

		if err := unm.Unmarshal(buf, resp); err != nil {
			return maybeUnknownEnum(err)
		}

		return nil
	}, opts...)
	if e != nil {
		return nil, e
	}
	op := &Operation{
		&zoneOperationsHandle{
			c:       c.operationClient,
			proto:   resp,
			project: req.GetProject(),
			zone:    req.GetZone(),
		},
	}
	return op, nil
}

// DeletePerInstanceConfigs deletes selected per-instance configurations for the managed instance group.
func (c *instanceGroupManagersRESTClient) DeletePerInstanceConfigs(ctx context.Context, req *computepb.DeletePerInstanceConfigsInstanceGroupManagerRequest, opts ...gax.CallOption) (*Operation, error) {
	m := protojson.MarshalOptions{AllowPartial: true}
	body := req.GetInstanceGroupManagersDeletePerInstanceConfigsReqResource()
	jsonReq, err := m.Marshal(body)
	if err != nil {
		return nil, err
	}

	baseUrl, err := url.Parse(c.endpoint)
	if err != nil {
		return nil, err
	}
	baseUrl.Path += fmt.Sprintf("/compute/v1/projects/%v/zones/%v/instanceGroupManagers/%v/deletePerInstanceConfigs", req.GetProject(), req.GetZone(), req.GetInstanceGroupManager())

	// Build HTTP headers from client and context metadata.
	md := metadata.Pairs("x-goog-request-params", fmt.Sprintf("%s=%v&%s=%v&%s=%v", "project", url.QueryEscape(req.GetProject()), "zone", url.QueryEscape(req.GetZone()), "instance_group_manager", url.QueryEscape(req.GetInstanceGroupManager())))

	headers := buildHeaders(ctx, c.xGoogMetadata, md, metadata.Pairs("Content-Type", "application/json"))
	opts = append((*c.CallOptions).DeletePerInstanceConfigs[0:len((*c.CallOptions).DeletePerInstanceConfigs):len((*c.CallOptions).DeletePerInstanceConfigs)], opts...)
	unm := protojson.UnmarshalOptions{AllowPartial: true, DiscardUnknown: true}
	resp := &computepb.Operation{}
	e := gax.Invoke(ctx, func(ctx context.Context, settings gax.CallSettings) error {
		if settings.Path != "" {
			baseUrl.Path = settings.Path
		}
		httpReq, err := http.NewRequest("POST", baseUrl.String(), bytes.NewReader(jsonReq))
		if err != nil {
			return err
		}
		httpReq = httpReq.WithContext(ctx)
		httpReq.Header = headers

		httpRsp, err := c.httpClient.Do(httpReq)
		if err != nil {
			return err
		}
		defer httpRsp.Body.Close()

		if err = googleapi.CheckResponse(httpRsp); err != nil {
			return err
		}

		buf, err := ioutil.ReadAll(httpRsp.Body)
		if err != nil {
			return err
		}

		if err := unm.Unmarshal(buf, resp); err != nil {
			return maybeUnknownEnum(err)
		}

		return nil
	}, opts...)
	if e != nil {
		return nil, e
	}
	op := &Operation{
		&zoneOperationsHandle{
			c:       c.operationClient,
			proto:   resp,
			project: req.GetProject(),
			zone:    req.GetZone(),
		},
	}
	return op, nil
}

// Get returns all of the details about the specified managed instance group.
func (c *instanceGroupManagersRESTClient) Get(ctx context.Context, req *computepb.GetInstanceGroupManagerRequest, opts ...gax.CallOption) (*computepb.InstanceGroupManager, error) {
	baseUrl, err := url.Parse(c.endpoint)
	if err != nil {
		return nil, err
	}
	baseUrl.Path += fmt.Sprintf("/compute/v1/projects/%v/zones/%v/instanceGroupManagers/%v", req.GetProject(), req.GetZone(), req.GetInstanceGroupManager())

	// Build HTTP headers from client and context metadata.
	md := metadata.Pairs("x-goog-request-params", fmt.Sprintf("%s=%v&%s=%v&%s=%v", "project", url.QueryEscape(req.GetProject()), "zone", url.QueryEscape(req.GetZone()), "instance_group_manager", url.QueryEscape(req.GetInstanceGroupManager())))

	headers := buildHeaders(ctx, c.xGoogMetadata, md, metadata.Pairs("Content-Type", "application/json"))
	opts = append((*c.CallOptions).Get[0:len((*c.CallOptions).Get):len((*c.CallOptions).Get)], opts...)
	unm := protojson.UnmarshalOptions{AllowPartial: true, DiscardUnknown: true}
	resp := &computepb.InstanceGroupManager{}
	e := gax.Invoke(ctx, func(ctx context.Context, settings gax.CallSettings) error {
		if settings.Path != "" {
			baseUrl.Path = settings.Path
		}
		httpReq, err := http.NewRequest("GET", baseUrl.String(), nil)
		if err != nil {
			return err
		}
		httpReq = httpReq.WithContext(ctx)
		httpReq.Header = headers

		httpRsp, err := c.httpClient.Do(httpReq)
		if err != nil {
			return err
		}
		defer httpRsp.Body.Close()

		if err = googleapi.CheckResponse(httpRsp); err != nil {
			return err
		}

		buf, err := ioutil.ReadAll(httpRsp.Body)
		if err != nil {
			return err
		}

		if err := unm.Unmarshal(buf, resp); err != nil {
			return maybeUnknownEnum(err)
		}

		return nil
	}, opts...)
	if e != nil {
		return nil, e
	}
	return resp, nil
}

// Insert creates a managed instance group using the information that you specify in the request. After the group is created, instances in the group are created using the specified instance template. This operation is marked as DONE when the group is created even if the instances in the group have not yet been created. You must separately verify the status of the individual instances with the listmanagedinstances method. A managed instance group can have up to 1000 VM instances per group. Please contact Cloud Support if you need an increase in this limit.
func (c *instanceGroupManagersRESTClient) Insert(ctx context.Context, req *computepb.InsertInstanceGroupManagerRequest, opts ...gax.CallOption) (*Operation, error) {
	m := protojson.MarshalOptions{AllowPartial: true}
	body := req.GetInstanceGroupManagerResource()
	jsonReq, err := m.Marshal(body)
	if err != nil {
		return nil, err
	}

	baseUrl, err := url.Parse(c.endpoint)
	if err != nil {
		return nil, err
	}
	baseUrl.Path += fmt.Sprintf("/compute/v1/projects/%v/zones/%v/instanceGroupManagers", req.GetProject(), req.GetZone())

	params := url.Values{}
	if req != nil && req.RequestId != nil {
		params.Add("requestId", fmt.Sprintf("%v", req.GetRequestId()))
	}

	baseUrl.RawQuery = params.Encode()

	// Build HTTP headers from client and context metadata.
	md := metadata.Pairs("x-goog-request-params", fmt.Sprintf("%s=%v&%s=%v", "project", url.QueryEscape(req.GetProject()), "zone", url.QueryEscape(req.GetZone())))

	headers := buildHeaders(ctx, c.xGoogMetadata, md, metadata.Pairs("Content-Type", "application/json"))
	opts = append((*c.CallOptions).Insert[0:len((*c.CallOptions).Insert):len((*c.CallOptions).Insert)], opts...)
	unm := protojson.UnmarshalOptions{AllowPartial: true, DiscardUnknown: true}
	resp := &computepb.Operation{}
	e := gax.Invoke(ctx, func(ctx context.Context, settings gax.CallSettings) error {
		if settings.Path != "" {
			baseUrl.Path = settings.Path
		}
		httpReq, err := http.NewRequest("POST", baseUrl.String(), bytes.NewReader(jsonReq))
		if err != nil {
			return err
		}
		httpReq = httpReq.WithContext(ctx)
		httpReq.Header = headers

		httpRsp, err := c.httpClient.Do(httpReq)
		if err != nil {
			return err
		}
		defer httpRsp.Body.Close()

		if err = googleapi.CheckResponse(httpRsp); err != nil {
			return err
		}

		buf, err := ioutil.ReadAll(httpRsp.Body)
		if err != nil {
			return err
		}

		if err := unm.Unmarshal(buf, resp); err != nil {
			return maybeUnknownEnum(err)
		}

		return nil
	}, opts...)
	if e != nil {
		return nil, e
	}
	op := &Operation{
		&zoneOperationsHandle{
			c:       c.operationClient,
			proto:   resp,
			project: req.GetProject(),
			zone:    req.GetZone(),
		},
	}
	return op, nil
}

// List retrieves a list of managed instance groups that are contained within the specified project and zone.
func (c *instanceGroupManagersRESTClient) List(ctx context.Context, req *computepb.ListInstanceGroupManagersRequest, opts ...gax.CallOption) *InstanceGroupManagerIterator {
	it := &InstanceGroupManagerIterator{}
	req = proto.Clone(req).(*computepb.ListInstanceGroupManagersRequest)
	unm := protojson.UnmarshalOptions{AllowPartial: true, DiscardUnknown: true}
	it.InternalFetch = func(pageSize int, pageToken string) ([]*computepb.InstanceGroupManager, string, error) {
		resp := &computepb.InstanceGroupManagerList{}
		if pageToken != "" {
			req.PageToken = proto.String(pageToken)
		}
		if pageSize > math.MaxInt32 {
			req.MaxResults = proto.Uint32(math.MaxInt32)
		} else if pageSize != 0 {
			req.MaxResults = proto.Uint32(uint32(pageSize))
		}
		baseUrl, err := url.Parse(c.endpoint)
		if err != nil {
			return nil, "", err
		}
		baseUrl.Path += fmt.Sprintf("/compute/v1/projects/%v/zones/%v/instanceGroupManagers", req.GetProject(), req.GetZone())

		params := url.Values{}
		if req != nil && req.Filter != nil {
			params.Add("filter", fmt.Sprintf("%v", req.GetFilter()))
		}
		if req != nil && req.MaxResults != nil {
			params.Add("maxResults", fmt.Sprintf("%v", req.GetMaxResults()))
		}
		if req != nil && req.OrderBy != nil {
			params.Add("orderBy", fmt.Sprintf("%v", req.GetOrderBy()))
		}
		if req != nil && req.PageToken != nil {
			params.Add("pageToken", fmt.Sprintf("%v", req.GetPageToken()))
		}
		if req != nil && req.ReturnPartialSuccess != nil {
			params.Add("returnPartialSuccess", fmt.Sprintf("%v", req.GetReturnPartialSuccess()))
		}

		baseUrl.RawQuery = params.Encode()

		// Build HTTP headers from client and context metadata.
		headers := buildHeaders(ctx, c.xGoogMetadata, metadata.Pairs("Content-Type", "application/json"))
		e := gax.Invoke(ctx, func(ctx context.Context, settings gax.CallSettings) error {
			if settings.Path != "" {
				baseUrl.Path = settings.Path
			}
			httpReq, err := http.NewRequest("GET", baseUrl.String(), nil)
			if err != nil {
				return err
			}
			httpReq.Header = headers

			httpRsp, err := c.httpClient.Do(httpReq)
			if err != nil {
				return err
			}
			defer httpRsp.Body.Close()

			if err = googleapi.CheckResponse(httpRsp); err != nil {
				return err
			}

			buf, err := ioutil.ReadAll(httpRsp.Body)
			if err != nil {
				return err
			}

			if err := unm.Unmarshal(buf, resp); err != nil {
				return maybeUnknownEnum(err)
			}

			return nil
		}, opts...)
		if e != nil {
			return nil, "", e
		}
		it.Response = resp
		return resp.GetItems(), resp.GetNextPageToken(), nil
	}

	fetch := func(pageSize int, pageToken string) (string, error) {
		items, nextPageToken, err := it.InternalFetch(pageSize, pageToken)
		if err != nil {
			return "", err
		}
		it.items = append(it.items, items...)
		return nextPageToken, nil
	}

	it.pageInfo, it.nextFunc = iterator.NewPageInfo(fetch, it.bufLen, it.takeBuf)
	it.pageInfo.MaxSize = int(req.GetMaxResults())
	it.pageInfo.Token = req.GetPageToken()

	return it
}

// ListErrors lists all errors thrown by actions on instances for a given managed instance group. The filter and orderBy query parameters are not supported.
func (c *instanceGroupManagersRESTClient) ListErrors(ctx context.Context, req *computepb.ListErrorsInstanceGroupManagersRequest, opts ...gax.CallOption) *InstanceManagedByIgmErrorIterator {
	it := &InstanceManagedByIgmErrorIterator{}
	req = proto.Clone(req).(*computepb.ListErrorsInstanceGroupManagersRequest)
	unm := protojson.UnmarshalOptions{AllowPartial: true, DiscardUnknown: true}
	it.InternalFetch = func(pageSize int, pageToken string) ([]*computepb.InstanceManagedByIgmError, string, error) {
		resp := &computepb.InstanceGroupManagersListErrorsResponse{}
		if pageToken != "" {
			req.PageToken = proto.String(pageToken)
		}
		if pageSize > math.MaxInt32 {
			req.MaxResults = proto.Uint32(math.MaxInt32)
		} else if pageSize != 0 {
			req.MaxResults = proto.Uint32(uint32(pageSize))
		}
		baseUrl, err := url.Parse(c.endpoint)
		if err != nil {
			return nil, "", err
		}
		baseUrl.Path += fmt.Sprintf("/compute/v1/projects/%v/zones/%v/instanceGroupManagers/%v/listErrors", req.GetProject(), req.GetZone(), req.GetInstanceGroupManager())

		params := url.Values{}
		if req != nil && req.Filter != nil {
			params.Add("filter", fmt.Sprintf("%v", req.GetFilter()))
		}
		if req != nil && req.MaxResults != nil {
			params.Add("maxResults", fmt.Sprintf("%v", req.GetMaxResults()))
		}
		if req != nil && req.OrderBy != nil {
			params.Add("orderBy", fmt.Sprintf("%v", req.GetOrderBy()))
		}
		if req != nil && req.PageToken != nil {
			params.Add("pageToken", fmt.Sprintf("%v", req.GetPageToken()))
		}
		if req != nil && req.ReturnPartialSuccess != nil {
			params.Add("returnPartialSuccess", fmt.Sprintf("%v", req.GetReturnPartialSuccess()))
		}

		baseUrl.RawQuery = params.Encode()

		// Build HTTP headers from client and context metadata.
		headers := buildHeaders(ctx, c.xGoogMetadata, metadata.Pairs("Content-Type", "application/json"))
		e := gax.Invoke(ctx, func(ctx context.Context, settings gax.CallSettings) error {
			if settings.Path != "" {
				baseUrl.Path = settings.Path
			}
			httpReq, err := http.NewRequest("GET", baseUrl.String(), nil)
			if err != nil {
				return err
			}
			httpReq.Header = headers

			httpRsp, err := c.httpClient.Do(httpReq)
			if err != nil {
				return err
			}
			defer httpRsp.Body.Close()

			if err = googleapi.CheckResponse(httpRsp); err != nil {
				return err
			}

			buf, err := ioutil.ReadAll(httpRsp.Body)
			if err != nil {
				return err
			}

			if err := unm.Unmarshal(buf, resp); err != nil {
				return maybeUnknownEnum(err)
			}

			return nil
		}, opts...)
		if e != nil {
			return nil, "", e
		}
		it.Response = resp
		return resp.GetItems(), resp.GetNextPageToken(), nil
	}

	fetch := func(pageSize int, pageToken string) (string, error) {
		items, nextPageToken, err := it.InternalFetch(pageSize, pageToken)
		if err != nil {
			return "", err
		}
		it.items = append(it.items, items...)
		return nextPageToken, nil
	}

	it.pageInfo, it.nextFunc = iterator.NewPageInfo(fetch, it.bufLen, it.takeBuf)
	it.pageInfo.MaxSize = int(req.GetMaxResults())
	it.pageInfo.Token = req.GetPageToken()

	return it
}

// ListManagedInstances lists all of the instances in the managed instance group. Each instance in the list has a currentAction, which indicates the action that the managed instance group is performing on the instance. For example, if the group is still creating an instance, the currentAction is CREATING. If a previous action failed, the list displays the errors for that failed action. The orderBy query parameter is not supported. The pageToken query parameter is supported only in the alpha and beta API and only if the group’s listManagedInstancesResults field is set to PAGINATED.
func (c *instanceGroupManagersRESTClient) ListManagedInstances(ctx context.Context, req *computepb.ListManagedInstancesInstanceGroupManagersRequest, opts ...gax.CallOption) *ManagedInstanceIterator {
	it := &ManagedInstanceIterator{}
	req = proto.Clone(req).(*computepb.ListManagedInstancesInstanceGroupManagersRequest)
	unm := protojson.UnmarshalOptions{AllowPartial: true, DiscardUnknown: true}
	it.InternalFetch = func(pageSize int, pageToken string) ([]*computepb.ManagedInstance, string, error) {
		resp := &computepb.InstanceGroupManagersListManagedInstancesResponse{}
		if pageToken != "" {
			req.PageToken = proto.String(pageToken)
		}
		if pageSize > math.MaxInt32 {
			req.MaxResults = proto.Uint32(math.MaxInt32)
		} else if pageSize != 0 {
			req.MaxResults = proto.Uint32(uint32(pageSize))
		}
		baseUrl, err := url.Parse(c.endpoint)
		if err != nil {
			return nil, "", err
		}
		baseUrl.Path += fmt.Sprintf("/compute/v1/projects/%v/zones/%v/instanceGroupManagers/%v/listManagedInstances", req.GetProject(), req.GetZone(), req.GetInstanceGroupManager())

		params := url.Values{}
		if req != nil && req.Filter != nil {
			params.Add("filter", fmt.Sprintf("%v", req.GetFilter()))
		}
		if req != nil && req.MaxResults != nil {
			params.Add("maxResults", fmt.Sprintf("%v", req.GetMaxResults()))
		}
		if req != nil && req.OrderBy != nil {
			params.Add("orderBy", fmt.Sprintf("%v", req.GetOrderBy()))
		}
		if req != nil && req.PageToken != nil {
			params.Add("pageToken", fmt.Sprintf("%v", req.GetPageToken()))
		}
		if req != nil && req.ReturnPartialSuccess != nil {
			params.Add("returnPartialSuccess", fmt.Sprintf("%v", req.GetReturnPartialSuccess()))
		}

		baseUrl.RawQuery = params.Encode()

		// Build HTTP headers from client and context metadata.
		headers := buildHeaders(ctx, c.xGoogMetadata, metadata.Pairs("Content-Type", "application/json"))
		e := gax.Invoke(ctx, func(ctx context.Context, settings gax.CallSettings) error {
			if settings.Path != "" {
				baseUrl.Path = settings.Path
			}
			httpReq, err := http.NewRequest("POST", baseUrl.String(), nil)
			if err != nil {
				return err
			}
			httpReq.Header = headers

			httpRsp, err := c.httpClient.Do(httpReq)
			if err != nil {
				return err
			}
			defer httpRsp.Body.Close()

			if err = googleapi.CheckResponse(httpRsp); err != nil {
				return err
			}

			buf, err := ioutil.ReadAll(httpRsp.Body)
			if err != nil {
				return err
			}

			if err := unm.Unmarshal(buf, resp); err != nil {
				return maybeUnknownEnum(err)
			}

			return nil
		}, opts...)
		if e != nil {
			return nil, "", e
		}
		it.Response = resp
		return resp.GetManagedInstances(), resp.GetNextPageToken(), nil
	}

	fetch := func(pageSize int, pageToken string) (string, error) {
		items, nextPageToken, err := it.InternalFetch(pageSize, pageToken)
		if err != nil {
			return "", err
		}
		it.items = append(it.items, items...)
		return nextPageToken, nil
	}

	it.pageInfo, it.nextFunc = iterator.NewPageInfo(fetch, it.bufLen, it.takeBuf)
	it.pageInfo.MaxSize = int(req.GetMaxResults())
	it.pageInfo.Token = req.GetPageToken()

	return it
}

// ListPerInstanceConfigs lists all of the per-instance configurations defined for the managed instance group. The orderBy query parameter is not supported.
func (c *instanceGroupManagersRESTClient) ListPerInstanceConfigs(ctx context.Context, req *computepb.ListPerInstanceConfigsInstanceGroupManagersRequest, opts ...gax.CallOption) *PerInstanceConfigIterator {
	it := &PerInstanceConfigIterator{}
	req = proto.Clone(req).(*computepb.ListPerInstanceConfigsInstanceGroupManagersRequest)
	unm := protojson.UnmarshalOptions{AllowPartial: true, DiscardUnknown: true}
	it.InternalFetch = func(pageSize int, pageToken string) ([]*computepb.PerInstanceConfig, string, error) {
		resp := &computepb.InstanceGroupManagersListPerInstanceConfigsResp{}
		if pageToken != "" {
			req.PageToken = proto.String(pageToken)
		}
		if pageSize > math.MaxInt32 {
			req.MaxResults = proto.Uint32(math.MaxInt32)
		} else if pageSize != 0 {
			req.MaxResults = proto.Uint32(uint32(pageSize))
		}
		baseUrl, err := url.Parse(c.endpoint)
		if err != nil {
			return nil, "", err
		}
		baseUrl.Path += fmt.Sprintf("/compute/v1/projects/%v/zones/%v/instanceGroupManagers/%v/listPerInstanceConfigs", req.GetProject(), req.GetZone(), req.GetInstanceGroupManager())

		params := url.Values{}
		if req != nil && req.Filter != nil {
			params.Add("filter", fmt.Sprintf("%v", req.GetFilter()))
		}
		if req != nil && req.MaxResults != nil {
			params.Add("maxResults", fmt.Sprintf("%v", req.GetMaxResults()))
		}
		if req != nil && req.OrderBy != nil {
			params.Add("orderBy", fmt.Sprintf("%v", req.GetOrderBy()))
		}
		if req != nil && req.PageToken != nil {
			params.Add("pageToken", fmt.Sprintf("%v", req.GetPageToken()))
		}
		if req != nil && req.ReturnPartialSuccess != nil {
			params.Add("returnPartialSuccess", fmt.Sprintf("%v", req.GetReturnPartialSuccess()))
		}

		baseUrl.RawQuery = params.Encode()

		// Build HTTP headers from client and context metadata.
		headers := buildHeaders(ctx, c.xGoogMetadata, metadata.Pairs("Content-Type", "application/json"))
		e := gax.Invoke(ctx, func(ctx context.Context, settings gax.CallSettings) error {
			if settings.Path != "" {
				baseUrl.Path = settings.Path
			}
			httpReq, err := http.NewRequest("POST", baseUrl.String(), nil)
			if err != nil {
				return err
			}
			httpReq.Header = headers

			httpRsp, err := c.httpClient.Do(httpReq)
			if err != nil {
				return err
			}
			defer httpRsp.Body.Close()

			if err = googleapi.CheckResponse(httpRsp); err != nil {
				return err
			}

			buf, err := ioutil.ReadAll(httpRsp.Body)
			if err != nil {
				return err
			}

			if err := unm.Unmarshal(buf, resp); err != nil {
				return maybeUnknownEnum(err)
			}

			return nil
		}, opts...)
		if e != nil {
			return nil, "", e
		}
		it.Response = resp
		return resp.GetItems(), resp.GetNextPageToken(), nil
	}

	fetch := func(pageSize int, pageToken string) (string, error) {
		items, nextPageToken, err := it.InternalFetch(pageSize, pageToken)
		if err != nil {
			return "", err
		}
		it.items = append(it.items, items...)
		return nextPageToken, nil
	}

	it.pageInfo, it.nextFunc = iterator.NewPageInfo(fetch, it.bufLen, it.takeBuf)
	it.pageInfo.MaxSize = int(req.GetMaxResults())
	it.pageInfo.Token = req.GetPageToken()

	return it
}

// Patch updates a managed instance group using the information that you specify in the request. This operation is marked as DONE when the group is patched even if the instances in the group are still in the process of being patched. You must separately verify the status of the individual instances with the listManagedInstances method. This method supports PATCH semantics and uses the JSON merge patch format and processing rules. If you update your group to specify a new template or instance configuration, it’s possible that your intended specification for each VM in the group is different from the current state of that VM. To learn how to apply an updated configuration to the VMs in a MIG, see Updating instances in a MIG.
func (c *instanceGroupManagersRESTClient) Patch(ctx context.Context, req *computepb.PatchInstanceGroupManagerRequest, opts ...gax.CallOption) (*Operation, error) {
	m := protojson.MarshalOptions{AllowPartial: true}
	body := req.GetInstanceGroupManagerResource()
	jsonReq, err := m.Marshal(body)
	if err != nil {
		return nil, err
	}

	baseUrl, err := url.Parse(c.endpoint)
	if err != nil {
		return nil, err
	}
	baseUrl.Path += fmt.Sprintf("/compute/v1/projects/%v/zones/%v/instanceGroupManagers/%v", req.GetProject(), req.GetZone(), req.GetInstanceGroupManager())

	params := url.Values{}
	if req != nil && req.RequestId != nil {
		params.Add("requestId", fmt.Sprintf("%v", req.GetRequestId()))
	}

	baseUrl.RawQuery = params.Encode()

	// Build HTTP headers from client and context metadata.
	md := metadata.Pairs("x-goog-request-params", fmt.Sprintf("%s=%v&%s=%v&%s=%v", "project", url.QueryEscape(req.GetProject()), "zone", url.QueryEscape(req.GetZone()), "instance_group_manager", url.QueryEscape(req.GetInstanceGroupManager())))

	headers := buildHeaders(ctx, c.xGoogMetadata, md, metadata.Pairs("Content-Type", "application/json"))
	opts = append((*c.CallOptions).Patch[0:len((*c.CallOptions).Patch):len((*c.CallOptions).Patch)], opts...)
	unm := protojson.UnmarshalOptions{AllowPartial: true, DiscardUnknown: true}
	resp := &computepb.Operation{}
	e := gax.Invoke(ctx, func(ctx context.Context, settings gax.CallSettings) error {
		if settings.Path != "" {
			baseUrl.Path = settings.Path
		}
		httpReq, err := http.NewRequest("PATCH", baseUrl.String(), bytes.NewReader(jsonReq))
		if err != nil {
			return err
		}
		httpReq = httpReq.WithContext(ctx)
		httpReq.Header = headers

		httpRsp, err := c.httpClient.Do(httpReq)
		if err != nil {
			return err
		}
		defer httpRsp.Body.Close()

		if err = googleapi.CheckResponse(httpRsp); err != nil {
			return err
		}

		buf, err := ioutil.ReadAll(httpRsp.Body)
		if err != nil {
			return err
		}

		if err := unm.Unmarshal(buf, resp); err != nil {
			return maybeUnknownEnum(err)
		}

		return nil
	}, opts...)
	if e != nil {
		return nil, e
	}
	op := &Operation{
		&zoneOperationsHandle{
			c:       c.operationClient,
			proto:   resp,
			project: req.GetProject(),
			zone:    req.GetZone(),
		},
	}
	return op, nil
}

// PatchPerInstanceConfigs inserts or patches per-instance configurations for the managed instance group. perInstanceConfig.name (at http://perInstanceConfig.name) serves as a key used to distinguish whether to perform insert or patch.
func (c *instanceGroupManagersRESTClient) PatchPerInstanceConfigs(ctx context.Context, req *computepb.PatchPerInstanceConfigsInstanceGroupManagerRequest, opts ...gax.CallOption) (*Operation, error) {
	m := protojson.MarshalOptions{AllowPartial: true}
	body := req.GetInstanceGroupManagersPatchPerInstanceConfigsReqResource()
	jsonReq, err := m.Marshal(body)
	if err != nil {
		return nil, err
	}

	baseUrl, err := url.Parse(c.endpoint)
	if err != nil {
		return nil, err
	}
	baseUrl.Path += fmt.Sprintf("/compute/v1/projects/%v/zones/%v/instanceGroupManagers/%v/patchPerInstanceConfigs", req.GetProject(), req.GetZone(), req.GetInstanceGroupManager())

	params := url.Values{}
	if req != nil && req.RequestId != nil {
		params.Add("requestId", fmt.Sprintf("%v", req.GetRequestId()))
	}

	baseUrl.RawQuery = params.Encode()

	// Build HTTP headers from client and context metadata.
	md := metadata.Pairs("x-goog-request-params", fmt.Sprintf("%s=%v&%s=%v&%s=%v", "project", url.QueryEscape(req.GetProject()), "zone", url.QueryEscape(req.GetZone()), "instance_group_manager", url.QueryEscape(req.GetInstanceGroupManager())))

	headers := buildHeaders(ctx, c.xGoogMetadata, md, metadata.Pairs("Content-Type", "application/json"))
	opts = append((*c.CallOptions).PatchPerInstanceConfigs[0:len((*c.CallOptions).PatchPerInstanceConfigs):len((*c.CallOptions).PatchPerInstanceConfigs)], opts...)
	unm := protojson.UnmarshalOptions{AllowPartial: true, DiscardUnknown: true}
	resp := &computepb.Operation{}
	e := gax.Invoke(ctx, func(ctx context.Context, settings gax.CallSettings) error {
		if settings.Path != "" {
			baseUrl.Path = settings.Path
		}
		httpReq, err := http.NewRequest("POST", baseUrl.String(), bytes.NewReader(jsonReq))
		if err != nil {
			return err
		}
		httpReq = httpReq.WithContext(ctx)
		httpReq.Header = headers

		httpRsp, err := c.httpClient.Do(httpReq)
		if err != nil {
			return err
		}
		defer httpRsp.Body.Close()

		if err = googleapi.CheckResponse(httpRsp); err != nil {
			return err
		}

		buf, err := ioutil.ReadAll(httpRsp.Body)
		if err != nil {
			return err
		}

		if err := unm.Unmarshal(buf, resp); err != nil {
			return maybeUnknownEnum(err)
		}

		return nil
	}, opts...)
	if e != nil {
		return nil, e
	}
	op := &Operation{
		&zoneOperationsHandle{
			c:       c.operationClient,
			proto:   resp,
			project: req.GetProject(),
			zone:    req.GetZone(),
		},
	}
	return op, nil
}

// RecreateInstances flags the specified VM instances in the managed instance group to be immediately recreated. Each instance is recreated using the group’s current configuration. This operation is marked as DONE when the flag is set even if the instances have not yet been recreated. You must separately verify the status of each instance by checking its currentAction field; for more information, see Checking the status of managed instances. If the group is part of a backend service that has enabled connection draining, it can take up to 60 seconds after the connection draining duration has elapsed before the VM instance is removed or deleted. You can specify a maximum of 1000 instances with this method per request.
func (c *instanceGroupManagersRESTClient) RecreateInstances(ctx context.Context, req *computepb.RecreateInstancesInstanceGroupManagerRequest, opts ...gax.CallOption) (*Operation, error) {
	m := protojson.MarshalOptions{AllowPartial: true}
	body := req.GetInstanceGroupManagersRecreateInstancesRequestResource()
	jsonReq, err := m.Marshal(body)
	if err != nil {
		return nil, err
	}

	baseUrl, err := url.Parse(c.endpoint)
	if err != nil {
		return nil, err
	}
	baseUrl.Path += fmt.Sprintf("/compute/v1/projects/%v/zones/%v/instanceGroupManagers/%v/recreateInstances", req.GetProject(), req.GetZone(), req.GetInstanceGroupManager())

	params := url.Values{}
	if req != nil && req.RequestId != nil {
		params.Add("requestId", fmt.Sprintf("%v", req.GetRequestId()))
	}

	baseUrl.RawQuery = params.Encode()

	// Build HTTP headers from client and context metadata.
	md := metadata.Pairs("x-goog-request-params", fmt.Sprintf("%s=%v&%s=%v&%s=%v", "project", url.QueryEscape(req.GetProject()), "zone", url.QueryEscape(req.GetZone()), "instance_group_manager", url.QueryEscape(req.GetInstanceGroupManager())))

	headers := buildHeaders(ctx, c.xGoogMetadata, md, metadata.Pairs("Content-Type", "application/json"))
	opts = append((*c.CallOptions).RecreateInstances[0:len((*c.CallOptions).RecreateInstances):len((*c.CallOptions).RecreateInstances)], opts...)
	unm := protojson.UnmarshalOptions{AllowPartial: true, DiscardUnknown: true}
	resp := &computepb.Operation{}
	e := gax.Invoke(ctx, func(ctx context.Context, settings gax.CallSettings) error {
		if settings.Path != "" {
			baseUrl.Path = settings.Path
		}
		httpReq, err := http.NewRequest("POST", baseUrl.String(), bytes.NewReader(jsonReq))
		if err != nil {
			return err
		}
		httpReq = httpReq.WithContext(ctx)
		httpReq.Header = headers

		httpRsp, err := c.httpClient.Do(httpReq)
		if err != nil {
			return err
		}
		defer httpRsp.Body.Close()

		if err = googleapi.CheckResponse(httpRsp); err != nil {
			return err
		}

		buf, err := ioutil.ReadAll(httpRsp.Body)
		if err != nil {
			return err
		}

		if err := unm.Unmarshal(buf, resp); err != nil {
			return maybeUnknownEnum(err)
		}

		return nil
	}, opts...)
	if e != nil {
		return nil, e
	}
	op := &Operation{
		&zoneOperationsHandle{
			c:       c.operationClient,
			proto:   resp,
			project: req.GetProject(),
			zone:    req.GetZone(),
		},
	}
	return op, nil
}

// Resize resizes the managed instance group. If you increase the size, the group creates new instances using the current instance template. If you decrease the size, the group deletes instances. The resize operation is marked DONE when the resize actions are scheduled even if the group has not yet added or deleted any instances. You must separately verify the status of the creating or deleting actions with the listmanagedinstances method. When resizing down, the instance group arbitrarily chooses the order in which VMs are deleted. The group takes into account some VM attributes when making the selection including: + The status of the VM instance. + The health of the VM instance. + The instance template version the VM is based on. + For regional managed instance groups, the location of the VM instance. This list is subject to change. If the group is part of a backend service that has enabled connection draining, it can take up to 60 seconds after the connection draining duration has elapsed before the VM instance is removed or deleted.
func (c *instanceGroupManagersRESTClient) Resize(ctx context.Context, req *computepb.ResizeInstanceGroupManagerRequest, opts ...gax.CallOption) (*Operation, error) {
	baseUrl, err := url.Parse(c.endpoint)
	if err != nil {
		return nil, err
	}
	baseUrl.Path += fmt.Sprintf("/compute/v1/projects/%v/zones/%v/instanceGroupManagers/%v/resize", req.GetProject(), req.GetZone(), req.GetInstanceGroupManager())

	params := url.Values{}
	if req != nil && req.RequestId != nil {
		params.Add("requestId", fmt.Sprintf("%v", req.GetRequestId()))
	}
	params.Add("size", fmt.Sprintf("%v", req.GetSize()))

	baseUrl.RawQuery = params.Encode()

	// Build HTTP headers from client and context metadata.
	md := metadata.Pairs("x-goog-request-params", fmt.Sprintf("%s=%v&%s=%v&%s=%v", "project", url.QueryEscape(req.GetProject()), "zone", url.QueryEscape(req.GetZone()), "instance_group_manager", url.QueryEscape(req.GetInstanceGroupManager())))

	headers := buildHeaders(ctx, c.xGoogMetadata, md, metadata.Pairs("Content-Type", "application/json"))
	opts = append((*c.CallOptions).Resize[0:len((*c.CallOptions).Resize):len((*c.CallOptions).Resize)], opts...)
	unm := protojson.UnmarshalOptions{AllowPartial: true, DiscardUnknown: true}
	resp := &computepb.Operation{}
	e := gax.Invoke(ctx, func(ctx context.Context, settings gax.CallSettings) error {
		if settings.Path != "" {
			baseUrl.Path = settings.Path
		}
		httpReq, err := http.NewRequest("POST", baseUrl.String(), nil)
		if err != nil {
			return err
		}
		httpReq = httpReq.WithContext(ctx)
		httpReq.Header = headers

		httpRsp, err := c.httpClient.Do(httpReq)
		if err != nil {
			return err
		}
		defer httpRsp.Body.Close()

		if err = googleapi.CheckResponse(httpRsp); err != nil {
			return err
		}

		buf, err := ioutil.ReadAll(httpRsp.Body)
		if err != nil {
			return err
		}

		if err := unm.Unmarshal(buf, resp); err != nil {
			return maybeUnknownEnum(err)
		}

		return nil
	}, opts...)
	if e != nil {
		return nil, e
	}
	op := &Operation{
		&zoneOperationsHandle{
			c:       c.operationClient,
			proto:   resp,
			project: req.GetProject(),
			zone:    req.GetZone(),
		},
	}
	return op, nil
}

// SetInstanceTemplate specifies the instance template to use when creating new instances in this group. The templates for existing instances in the group do not change unless you run recreateInstances, run applyUpdatesToInstances, or set the group’s updatePolicy.type to PROACTIVE.
func (c *instanceGroupManagersRESTClient) SetInstanceTemplate(ctx context.Context, req *computepb.SetInstanceTemplateInstanceGroupManagerRequest, opts ...gax.CallOption) (*Operation, error) {
	m := protojson.MarshalOptions{AllowPartial: true}
	body := req.GetInstanceGroupManagersSetInstanceTemplateRequestResource()
	jsonReq, err := m.Marshal(body)
	if err != nil {
		return nil, err
	}

	baseUrl, err := url.Parse(c.endpoint)
	if err != nil {
		return nil, err
	}
	baseUrl.Path += fmt.Sprintf("/compute/v1/projects/%v/zones/%v/instanceGroupManagers/%v/setInstanceTemplate", req.GetProject(), req.GetZone(), req.GetInstanceGroupManager())

	params := url.Values{}
	if req != nil && req.RequestId != nil {
		params.Add("requestId", fmt.Sprintf("%v", req.GetRequestId()))
	}

	baseUrl.RawQuery = params.Encode()

	// Build HTTP headers from client and context metadata.
	md := metadata.Pairs("x-goog-request-params", fmt.Sprintf("%s=%v&%s=%v&%s=%v", "project", url.QueryEscape(req.GetProject()), "zone", url.QueryEscape(req.GetZone()), "instance_group_manager", url.QueryEscape(req.GetInstanceGroupManager())))

	headers := buildHeaders(ctx, c.xGoogMetadata, md, metadata.Pairs("Content-Type", "application/json"))
	opts = append((*c.CallOptions).SetInstanceTemplate[0:len((*c.CallOptions).SetInstanceTemplate):len((*c.CallOptions).SetInstanceTemplate)], opts...)
	unm := protojson.UnmarshalOptions{AllowPartial: true, DiscardUnknown: true}
	resp := &computepb.Operation{}
	e := gax.Invoke(ctx, func(ctx context.Context, settings gax.CallSettings) error {
		if settings.Path != "" {
			baseUrl.Path = settings.Path
		}
		httpReq, err := http.NewRequest("POST", baseUrl.String(), bytes.NewReader(jsonReq))
		if err != nil {
			return err
		}
		httpReq = httpReq.WithContext(ctx)
		httpReq.Header = headers

		httpRsp, err := c.httpClient.Do(httpReq)
		if err != nil {
			return err
		}
		defer httpRsp.Body.Close()

		if err = googleapi.CheckResponse(httpRsp); err != nil {
			return err
		}

		buf, err := ioutil.ReadAll(httpRsp.Body)
		if err != nil {
			return err
		}

		if err := unm.Unmarshal(buf, resp); err != nil {
			return maybeUnknownEnum(err)
		}

		return nil
	}, opts...)
	if e != nil {
		return nil, e
	}
	op := &Operation{
		&zoneOperationsHandle{
			c:       c.operationClient,
			proto:   resp,
			project: req.GetProject(),
			zone:    req.GetZone(),
		},
	}
	return op, nil
}

// SetTargetPools modifies the target pools to which all instances in this managed instance group are assigned. The target pools automatically apply to all of the instances in the managed instance group. This operation is marked DONE when you make the request even if the instances have not yet been added to their target pools. The change might take some time to apply to all of the instances in the group depending on the size of the group.
func (c *instanceGroupManagersRESTClient) SetTargetPools(ctx context.Context, req *computepb.SetTargetPoolsInstanceGroupManagerRequest, opts ...gax.CallOption) (*Operation, error) {
	m := protojson.MarshalOptions{AllowPartial: true}
	body := req.GetInstanceGroupManagersSetTargetPoolsRequestResource()
	jsonReq, err := m.Marshal(body)
	if err != nil {
		return nil, err
	}

	baseUrl, err := url.Parse(c.endpoint)
	if err != nil {
		return nil, err
	}
	baseUrl.Path += fmt.Sprintf("/compute/v1/projects/%v/zones/%v/instanceGroupManagers/%v/setTargetPools", req.GetProject(), req.GetZone(), req.GetInstanceGroupManager())

	params := url.Values{}
	if req != nil && req.RequestId != nil {
		params.Add("requestId", fmt.Sprintf("%v", req.GetRequestId()))
	}

	baseUrl.RawQuery = params.Encode()

	// Build HTTP headers from client and context metadata.
	md := metadata.Pairs("x-goog-request-params", fmt.Sprintf("%s=%v&%s=%v&%s=%v", "project", url.QueryEscape(req.GetProject()), "zone", url.QueryEscape(req.GetZone()), "instance_group_manager", url.QueryEscape(req.GetInstanceGroupManager())))

	headers := buildHeaders(ctx, c.xGoogMetadata, md, metadata.Pairs("Content-Type", "application/json"))
	opts = append((*c.CallOptions).SetTargetPools[0:len((*c.CallOptions).SetTargetPools):len((*c.CallOptions).SetTargetPools)], opts...)
	unm := protojson.UnmarshalOptions{AllowPartial: true, DiscardUnknown: true}
	resp := &computepb.Operation{}
	e := gax.Invoke(ctx, func(ctx context.Context, settings gax.CallSettings) error {
		if settings.Path != "" {
			baseUrl.Path = settings.Path
		}
		httpReq, err := http.NewRequest("POST", baseUrl.String(), bytes.NewReader(jsonReq))
		if err != nil {
			return err
		}
		httpReq = httpReq.WithContext(ctx)
		httpReq.Header = headers

		httpRsp, err := c.httpClient.Do(httpReq)
		if err != nil {
			return err
		}
		defer httpRsp.Body.Close()

		if err = googleapi.CheckResponse(httpRsp); err != nil {
			return err
		}

		buf, err := ioutil.ReadAll(httpRsp.Body)
		if err != nil {
			return err
		}

		if err := unm.Unmarshal(buf, resp); err != nil {
			return maybeUnknownEnum(err)
		}

		return nil
	}, opts...)
	if e != nil {
		return nil, e
	}
	op := &Operation{
		&zoneOperationsHandle{
			c:       c.operationClient,
			proto:   resp,
			project: req.GetProject(),
			zone:    req.GetZone(),
		},
	}
	return op, nil
}

// UpdatePerInstanceConfigs inserts or updates per-instance configurations for the managed instance group. perInstanceConfig.name (at http://perInstanceConfig.name) serves as a key used to distinguish whether to perform insert or patch.
func (c *instanceGroupManagersRESTClient) UpdatePerInstanceConfigs(ctx context.Context, req *computepb.UpdatePerInstanceConfigsInstanceGroupManagerRequest, opts ...gax.CallOption) (*Operation, error) {
	m := protojson.MarshalOptions{AllowPartial: true}
	body := req.GetInstanceGroupManagersUpdatePerInstanceConfigsReqResource()
	jsonReq, err := m.Marshal(body)
	if err != nil {
		return nil, err
	}

	baseUrl, err := url.Parse(c.endpoint)
	if err != nil {
		return nil, err
	}
	baseUrl.Path += fmt.Sprintf("/compute/v1/projects/%v/zones/%v/instanceGroupManagers/%v/updatePerInstanceConfigs", req.GetProject(), req.GetZone(), req.GetInstanceGroupManager())

	params := url.Values{}
	if req != nil && req.RequestId != nil {
		params.Add("requestId", fmt.Sprintf("%v", req.GetRequestId()))
	}

	baseUrl.RawQuery = params.Encode()

	// Build HTTP headers from client and context metadata.
	md := metadata.Pairs("x-goog-request-params", fmt.Sprintf("%s=%v&%s=%v&%s=%v", "project", url.QueryEscape(req.GetProject()), "zone", url.QueryEscape(req.GetZone()), "instance_group_manager", url.QueryEscape(req.GetInstanceGroupManager())))

	headers := buildHeaders(ctx, c.xGoogMetadata, md, metadata.Pairs("Content-Type", "application/json"))
	opts = append((*c.CallOptions).UpdatePerInstanceConfigs[0:len((*c.CallOptions).UpdatePerInstanceConfigs):len((*c.CallOptions).UpdatePerInstanceConfigs)], opts...)
	unm := protojson.UnmarshalOptions{AllowPartial: true, DiscardUnknown: true}
	resp := &computepb.Operation{}
	e := gax.Invoke(ctx, func(ctx context.Context, settings gax.CallSettings) error {
		if settings.Path != "" {
			baseUrl.Path = settings.Path
		}
		httpReq, err := http.NewRequest("POST", baseUrl.String(), bytes.NewReader(jsonReq))
		if err != nil {
			return err
		}
		httpReq = httpReq.WithContext(ctx)
		httpReq.Header = headers

		httpRsp, err := c.httpClient.Do(httpReq)
		if err != nil {
			return err
		}
		defer httpRsp.Body.Close()

		if err = googleapi.CheckResponse(httpRsp); err != nil {
			return err
		}

		buf, err := ioutil.ReadAll(httpRsp.Body)
		if err != nil {
			return err
		}

		if err := unm.Unmarshal(buf, resp); err != nil {
			return maybeUnknownEnum(err)
		}

		return nil
	}, opts...)
	if e != nil {
		return nil, e
	}
	op := &Operation{
		&zoneOperationsHandle{
			c:       c.operationClient,
			proto:   resp,
			project: req.GetProject(),
			zone:    req.GetZone(),
		},
	}
	return op, nil
}

// InstanceGroupManagerIterator manages a stream of *computepb.InstanceGroupManager.
type InstanceGroupManagerIterator struct {
	items    []*computepb.InstanceGroupManager
	pageInfo *iterator.PageInfo
	nextFunc func() error

	// Response is the raw response for the current page.
	// It must be cast to the RPC response type.
	// Calling Next() or InternalFetch() updates this value.
	Response interface{}

	// InternalFetch is for use by the Google Cloud Libraries only.
	// It is not part of the stable interface of this package.
	//
	// InternalFetch returns results from a single call to the underlying RPC.
	// The number of results is no greater than pageSize.
	// If there are no more results, nextPageToken is empty and err is nil.
	InternalFetch func(pageSize int, pageToken string) (results []*computepb.InstanceGroupManager, nextPageToken string, err error)
}

// PageInfo supports pagination. See the google.golang.org/api/iterator package for details.
func (it *InstanceGroupManagerIterator) PageInfo() *iterator.PageInfo {
	return it.pageInfo
}

// Next returns the next result. Its second return value is iterator.Done if there are no more
// results. Once Next returns Done, all subsequent calls will return Done.
func (it *InstanceGroupManagerIterator) Next() (*computepb.InstanceGroupManager, error) {
	var item *computepb.InstanceGroupManager
	if err := it.nextFunc(); err != nil {
		return item, err
	}
	item = it.items[0]
	it.items = it.items[1:]
	return item, nil
}

func (it *InstanceGroupManagerIterator) bufLen() int {
	return len(it.items)
}

func (it *InstanceGroupManagerIterator) takeBuf() interface{} {
	b := it.items
	it.items = nil
	return b
}

// InstanceGroupManagersScopedListPair is a holder type for string/*computepb.InstanceGroupManagersScopedList map entries
type InstanceGroupManagersScopedListPair struct {
	Key   string
	Value *computepb.InstanceGroupManagersScopedList
}

// InstanceGroupManagersScopedListPairIterator manages a stream of InstanceGroupManagersScopedListPair.
type InstanceGroupManagersScopedListPairIterator struct {
	items    []InstanceGroupManagersScopedListPair
	pageInfo *iterator.PageInfo
	nextFunc func() error

	// Response is the raw response for the current page.
	// It must be cast to the RPC response type.
	// Calling Next() or InternalFetch() updates this value.
	Response interface{}

	// InternalFetch is for use by the Google Cloud Libraries only.
	// It is not part of the stable interface of this package.
	//
	// InternalFetch returns results from a single call to the underlying RPC.
	// The number of results is no greater than pageSize.
	// If there are no more results, nextPageToken is empty and err is nil.
	InternalFetch func(pageSize int, pageToken string) (results []InstanceGroupManagersScopedListPair, nextPageToken string, err error)
}

// PageInfo supports pagination. See the google.golang.org/api/iterator package for details.
func (it *InstanceGroupManagersScopedListPairIterator) PageInfo() *iterator.PageInfo {
	return it.pageInfo
}

// Next returns the next result. Its second return value is iterator.Done if there are no more
// results. Once Next returns Done, all subsequent calls will return Done.
func (it *InstanceGroupManagersScopedListPairIterator) Next() (InstanceGroupManagersScopedListPair, error) {
	var item InstanceGroupManagersScopedListPair
	if err := it.nextFunc(); err != nil {
		return item, err
	}
	item = it.items[0]
	it.items = it.items[1:]
	return item, nil
}

func (it *InstanceGroupManagersScopedListPairIterator) bufLen() int {
	return len(it.items)
}

func (it *InstanceGroupManagersScopedListPairIterator) takeBuf() interface{} {
	b := it.items
	it.items = nil
	return b
}

// InstanceManagedByIgmErrorIterator manages a stream of *computepb.InstanceManagedByIgmError.
type InstanceManagedByIgmErrorIterator struct {
	items    []*computepb.InstanceManagedByIgmError
	pageInfo *iterator.PageInfo
	nextFunc func() error

	// Response is the raw response for the current page.
	// It must be cast to the RPC response type.
	// Calling Next() or InternalFetch() updates this value.
	Response interface{}

	// InternalFetch is for use by the Google Cloud Libraries only.
	// It is not part of the stable interface of this package.
	//
	// InternalFetch returns results from a single call to the underlying RPC.
	// The number of results is no greater than pageSize.
	// If there are no more results, nextPageToken is empty and err is nil.
	InternalFetch func(pageSize int, pageToken string) (results []*computepb.InstanceManagedByIgmError, nextPageToken string, err error)
}

// PageInfo supports pagination. See the google.golang.org/api/iterator package for details.
func (it *InstanceManagedByIgmErrorIterator) PageInfo() *iterator.PageInfo {
	return it.pageInfo
}

// Next returns the next result. Its second return value is iterator.Done if there are no more
// results. Once Next returns Done, all subsequent calls will return Done.
func (it *InstanceManagedByIgmErrorIterator) Next() (*computepb.InstanceManagedByIgmError, error) {
	var item *computepb.InstanceManagedByIgmError
	if err := it.nextFunc(); err != nil {
		return item, err
	}
	item = it.items[0]
	it.items = it.items[1:]
	return item, nil
}

func (it *InstanceManagedByIgmErrorIterator) bufLen() int {
	return len(it.items)
}

func (it *InstanceManagedByIgmErrorIterator) takeBuf() interface{} {
	b := it.items
	it.items = nil
	return b
}

// ManagedInstanceIterator manages a stream of *computepb.ManagedInstance.
type ManagedInstanceIterator struct {
	items    []*computepb.ManagedInstance
	pageInfo *iterator.PageInfo
	nextFunc func() error

	// Response is the raw response for the current page.
	// It must be cast to the RPC response type.
	// Calling Next() or InternalFetch() updates this value.
	Response interface{}

	// InternalFetch is for use by the Google Cloud Libraries only.
	// It is not part of the stable interface of this package.
	//
	// InternalFetch returns results from a single call to the underlying RPC.
	// The number of results is no greater than pageSize.
	// If there are no more results, nextPageToken is empty and err is nil.
	InternalFetch func(pageSize int, pageToken string) (results []*computepb.ManagedInstance, nextPageToken string, err error)
}

// PageInfo supports pagination. See the google.golang.org/api/iterator package for details.
func (it *ManagedInstanceIterator) PageInfo() *iterator.PageInfo {
	return it.pageInfo
}

// Next returns the next result. Its second return value is iterator.Done if there are no more
// results. Once Next returns Done, all subsequent calls will return Done.
func (it *ManagedInstanceIterator) Next() (*computepb.ManagedInstance, error) {
	var item *computepb.ManagedInstance
	if err := it.nextFunc(); err != nil {
		return item, err
	}
	item = it.items[0]
	it.items = it.items[1:]
	return item, nil
}

func (it *ManagedInstanceIterator) bufLen() int {
	return len(it.items)
}

func (it *ManagedInstanceIterator) takeBuf() interface{} {
	b := it.items
	it.items = nil
	return b
}

// PerInstanceConfigIterator manages a stream of *computepb.PerInstanceConfig.
type PerInstanceConfigIterator struct {
	items    []*computepb.PerInstanceConfig
	pageInfo *iterator.PageInfo
	nextFunc func() error

	// Response is the raw response for the current page.
	// It must be cast to the RPC response type.
	// Calling Next() or InternalFetch() updates this value.
	Response interface{}

	// InternalFetch is for use by the Google Cloud Libraries only.
	// It is not part of the stable interface of this package.
	//
	// InternalFetch returns results from a single call to the underlying RPC.
	// The number of results is no greater than pageSize.
	// If there are no more results, nextPageToken is empty and err is nil.
	InternalFetch func(pageSize int, pageToken string) (results []*computepb.PerInstanceConfig, nextPageToken string, err error)
}

// PageInfo supports pagination. See the google.golang.org/api/iterator package for details.
func (it *PerInstanceConfigIterator) PageInfo() *iterator.PageInfo {
	return it.pageInfo
}

// Next returns the next result. Its second return value is iterator.Done if there are no more
// results. Once Next returns Done, all subsequent calls will return Done.
func (it *PerInstanceConfigIterator) Next() (*computepb.PerInstanceConfig, error) {
	var item *computepb.PerInstanceConfig
	if err := it.nextFunc(); err != nil {
		return item, err
	}
	item = it.items[0]
	it.items = it.items[1:]
	return item, nil
}

func (it *PerInstanceConfigIterator) bufLen() int {
	return len(it.items)
}

func (it *PerInstanceConfigIterator) takeBuf() interface{} {
	b := it.items
	it.items = nil
	return b
}
