instance_groups_client.go

// 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"
	"time"

	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 newInstanceGroupsClientHook clientHook

// InstanceGroupsCallOptions contains the retry settings for each method of InstanceGroupsClient.
type InstanceGroupsCallOptions struct {
	AddInstances    []gax.CallOption
	AggregatedList  []gax.CallOption
	Delete          []gax.CallOption
	Get             []gax.CallOption
	Insert          []gax.CallOption
	List            []gax.CallOption
	ListInstances   []gax.CallOption
	RemoveInstances []gax.CallOption
	SetNamedPorts   []gax.CallOption
}

func defaultInstanceGroupsRESTCallOptions() *InstanceGroupsCallOptions {
	return &InstanceGroupsCallOptions{
		AddInstances: []gax.CallOption{},
		AggregatedList: []gax.CallOption{
			gax.WithRetry(func() gax.Retryer {
				return gax.OnHTTPCodes(gax.Backoff{
					Initial:    100 * time.Millisecond,
					Max:        60000 * time.Millisecond,
					Multiplier: 1.30,
				},
					http.StatusGatewayTimeout,
					http.StatusServiceUnavailable)
			}),
		},
		Delete: []gax.CallOption{},
		Get: []gax.CallOption{
			gax.WithRetry(func() gax.Retryer {
				return gax.OnHTTPCodes(gax.Backoff{
					Initial:    100 * time.Millisecond,
					Max:        60000 * time.Millisecond,
					Multiplier: 1.30,
				},
					http.StatusGatewayTimeout,
					http.StatusServiceUnavailable)
			}),
		},
		Insert: []gax.CallOption{},
		List: []gax.CallOption{
			gax.WithRetry(func() gax.Retryer {
				return gax.OnHTTPCodes(gax.Backoff{
					Initial:    100 * time.Millisecond,
					Max:        60000 * time.Millisecond,
					Multiplier: 1.30,
				},
					http.StatusGatewayTimeout,
					http.StatusServiceUnavailable)
			}),
		},
		ListInstances:   []gax.CallOption{},
		RemoveInstances: []gax.CallOption{},
		SetNamedPorts:   []gax.CallOption{},
	}
}

// internalInstanceGroupsClient is an interface that defines the methods available from Google Compute Engine API.
type internalInstanceGroupsClient interface {
	Close() error
	setGoogleClientInfo(...string)
	Connection() *grpc.ClientConn
	AddInstances(context.Context, *computepb.AddInstancesInstanceGroupRequest, ...gax.CallOption) (*Operation, error)
	AggregatedList(context.Context, *computepb.AggregatedListInstanceGroupsRequest, ...gax.CallOption) *InstanceGroupsScopedListPairIterator
	Delete(context.Context, *computepb.DeleteInstanceGroupRequest, ...gax.CallOption) (*Operation, error)
	Get(context.Context, *computepb.GetInstanceGroupRequest, ...gax.CallOption) (*computepb.InstanceGroup, error)
	Insert(context.Context, *computepb.InsertInstanceGroupRequest, ...gax.CallOption) (*Operation, error)
	List(context.Context, *computepb.ListInstanceGroupsRequest, ...gax.CallOption) *InstanceGroupIterator
	ListInstances(context.Context, *computepb.ListInstancesInstanceGroupsRequest, ...gax.CallOption) *InstanceWithNamedPortsIterator
	RemoveInstances(context.Context, *computepb.RemoveInstancesInstanceGroupRequest, ...gax.CallOption) (*Operation, error)
	SetNamedPorts(context.Context, *computepb.SetNamedPortsInstanceGroupRequest, ...gax.CallOption) (*Operation, error)
}

// InstanceGroupsClient 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 InstanceGroups API.
type InstanceGroupsClient struct {
	// The internal transport-dependent client.
	internalClient internalInstanceGroupsClient

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

// 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 *InstanceGroupsClient) 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 *InstanceGroupsClient) 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 *InstanceGroupsClient) Connection() *grpc.ClientConn {
	return c.internalClient.Connection()
}

// AddInstances adds a list of instances to the specified instance group. All of the instances in the instance group must be in the same network/subnetwork. Read Adding instances for more information.
func (c *InstanceGroupsClient) AddInstances(ctx context.Context, req *computepb.AddInstancesInstanceGroupRequest, opts ...gax.CallOption) (*Operation, error) {
	return c.internalClient.AddInstances(ctx, req, opts...)
}

// AggregatedList retrieves the list of instance groups and sorts them by zone.
func (c *InstanceGroupsClient) AggregatedList(ctx context.Context, req *computepb.AggregatedListInstanceGroupsRequest, opts ...gax.CallOption) *InstanceGroupsScopedListPairIterator {
	return c.internalClient.AggregatedList(ctx, req, opts...)
}

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

// Get returns the specified zonal instance group. Get a list of available zonal instance groups by making a list() request. For managed instance groups, use the instanceGroupManagers or regionInstanceGroupManagers methods instead.
func (c *InstanceGroupsClient) Get(ctx context.Context, req *computepb.GetInstanceGroupRequest, opts ...gax.CallOption) (*computepb.InstanceGroup, error) {
	return c.internalClient.Get(ctx, req, opts...)
}

// Insert creates an instance group in the specified project using the parameters that are included in the request.
func (c *InstanceGroupsClient) Insert(ctx context.Context, req *computepb.InsertInstanceGroupRequest, opts ...gax.CallOption) (*Operation, error) {
	return c.internalClient.Insert(ctx, req, opts...)
}

// List retrieves the list of zonal instance group resources contained within the specified zone. For managed instance groups, use the instanceGroupManagers or regionInstanceGroupManagers methods instead.
func (c *InstanceGroupsClient) List(ctx context.Context, req *computepb.ListInstanceGroupsRequest, opts ...gax.CallOption) *InstanceGroupIterator {
	return c.internalClient.List(ctx, req, opts...)
}

// ListInstances lists the instances in the specified instance group. The orderBy query parameter is not supported. The filter query parameter is supported, but only for expressions that use eq (equal) or ne (not equal) operators.
func (c *InstanceGroupsClient) ListInstances(ctx context.Context, req *computepb.ListInstancesInstanceGroupsRequest, opts ...gax.CallOption) *InstanceWithNamedPortsIterator {
	return c.internalClient.ListInstances(ctx, req, opts...)
}

// RemoveInstances removes one or more instances from the specified instance group, but does not delete those 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 before the VM instance is removed or deleted.
func (c *InstanceGroupsClient) RemoveInstances(ctx context.Context, req *computepb.RemoveInstancesInstanceGroupRequest, opts ...gax.CallOption) (*Operation, error) {
	return c.internalClient.RemoveInstances(ctx, req, opts...)
}

// SetNamedPorts sets the named ports for the specified instance group.
func (c *InstanceGroupsClient) SetNamedPorts(ctx context.Context, req *computepb.SetNamedPortsInstanceGroupRequest, opts ...gax.CallOption) (*Operation, error) {
	return c.internalClient.SetNamedPorts(ctx, req, opts...)
}

// Methods, except Close, may be called concurrently. However, fields must not be modified concurrently with method calls.
type instanceGroupsRESTClient 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 InstanceGroupsClient
	CallOptions **InstanceGroupsCallOptions
}

// NewInstanceGroupsRESTClient creates a new instance groups rest client.
//
// The InstanceGroups API.
func NewInstanceGroupsRESTClient(ctx context.Context, opts ...option.ClientOption) (*InstanceGroupsClient, error) {
	clientOpts := append(defaultInstanceGroupsRESTClientOptions(), opts...)
	httpClient, endpoint, err := httptransport.NewClient(ctx, clientOpts...)
	if err != nil {
		return nil, err
	}

	callOpts := defaultInstanceGroupsRESTCallOptions()
	c := &instanceGroupsRESTClient{
		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 &InstanceGroupsClient{internalClient: c, CallOptions: callOpts}, nil
}

func defaultInstanceGroupsRESTClientOptions() []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 *instanceGroupsRESTClient) 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 *instanceGroupsRESTClient) 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 *instanceGroupsRESTClient) Connection() *grpc.ClientConn {
	return nil
}

// AddInstances adds a list of instances to the specified instance group. All of the instances in the instance group must be in the same network/subnetwork. Read Adding instances for more information.
func (c *instanceGroupsRESTClient) AddInstances(ctx context.Context, req *computepb.AddInstancesInstanceGroupRequest, opts ...gax.CallOption) (*Operation, error) {
	m := protojson.MarshalOptions{AllowPartial: true}
	body := req.GetInstanceGroupsAddInstancesRequestResource()
	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/instanceGroups/%v/addInstances", req.GetProject(), req.GetZone(), req.GetInstanceGroup())

	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", url.QueryEscape(req.GetInstanceGroup())))

	headers := buildHeaders(ctx, c.xGoogMetadata, md, metadata.Pairs("Content-Type", "application/json"))
	opts = append((*c.CallOptions).AddInstances[0:len((*c.CallOptions).AddInstances):len((*c.CallOptions).AddInstances)], 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 instance groups and sorts them by zone.
func (c *instanceGroupsRESTClient) AggregatedList(ctx context.Context, req *computepb.AggregatedListInstanceGroupsRequest, opts ...gax.CallOption) *InstanceGroupsScopedListPairIterator {
	it := &InstanceGroupsScopedListPairIterator{}
	req = proto.Clone(req).(*computepb.AggregatedListInstanceGroupsRequest)
	unm := protojson.UnmarshalOptions{AllowPartial: true, DiscardUnknown: true}
	it.InternalFetch = func(pageSize int, pageToken string) ([]InstanceGroupsScopedListPair, string, error) {
		resp := &computepb.InstanceGroupAggregatedList{}
		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/instanceGroups", 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([]InstanceGroupsScopedListPair, 0, len(resp.GetItems()))
		for k, v := range resp.GetItems() {
			elems = append(elems, InstanceGroupsScopedListPair{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
}

// Delete deletes the specified instance group. The instances in the group are not deleted. Note that instance group must not belong to a backend service. Read Deleting an instance group for more information.
func (c *instanceGroupsRESTClient) Delete(ctx context.Context, req *computepb.DeleteInstanceGroupRequest, 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/instanceGroups/%v", req.GetProject(), req.GetZone(), req.GetInstanceGroup())

	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", url.QueryEscape(req.GetInstanceGroup())))

	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
}

// Get returns the specified zonal instance group. Get a list of available zonal instance groups by making a list() request. For managed instance groups, use the instanceGroupManagers or regionInstanceGroupManagers methods instead.
func (c *instanceGroupsRESTClient) Get(ctx context.Context, req *computepb.GetInstanceGroupRequest, opts ...gax.CallOption) (*computepb.InstanceGroup, error) {
	baseUrl, err := url.Parse(c.endpoint)
	if err != nil {
		return nil, err
	}
	baseUrl.Path += fmt.Sprintf("/compute/v1/projects/%v/zones/%v/instanceGroups/%v", req.GetProject(), req.GetZone(), req.GetInstanceGroup())

	// 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", url.QueryEscape(req.GetInstanceGroup())))

	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.InstanceGroup{}
	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 an instance group in the specified project using the parameters that are included in the request.
func (c *instanceGroupsRESTClient) Insert(ctx context.Context, req *computepb.InsertInstanceGroupRequest, opts ...gax.CallOption) (*Operation, error) {
	m := protojson.MarshalOptions{AllowPartial: true}
	body := req.GetInstanceGroupResource()
	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/instanceGroups", 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 the list of zonal instance group resources contained within the specified zone. For managed instance groups, use the instanceGroupManagers or regionInstanceGroupManagers methods instead.
func (c *instanceGroupsRESTClient) List(ctx context.Context, req *computepb.ListInstanceGroupsRequest, opts ...gax.CallOption) *InstanceGroupIterator {
	it := &InstanceGroupIterator{}
	req = proto.Clone(req).(*computepb.ListInstanceGroupsRequest)
	unm := protojson.UnmarshalOptions{AllowPartial: true, DiscardUnknown: true}
	it.InternalFetch = func(pageSize int, pageToken string) ([]*computepb.InstanceGroup, string, error) {
		resp := &computepb.InstanceGroupList{}
		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/instanceGroups", 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
}

// ListInstances lists the instances in the specified instance group. The orderBy query parameter is not supported. The filter query parameter is supported, but only for expressions that use eq (equal) or ne (not equal) operators.
func (c *instanceGroupsRESTClient) ListInstances(ctx context.Context, req *computepb.ListInstancesInstanceGroupsRequest, opts ...gax.CallOption) *InstanceWithNamedPortsIterator {
	it := &InstanceWithNamedPortsIterator{}
	req = proto.Clone(req).(*computepb.ListInstancesInstanceGroupsRequest)
	m := protojson.MarshalOptions{AllowPartial: true}
	unm := protojson.UnmarshalOptions{AllowPartial: true, DiscardUnknown: true}
	it.InternalFetch = func(pageSize int, pageToken string) ([]*computepb.InstanceWithNamedPorts, string, error) {
		resp := &computepb.InstanceGroupsListInstances{}
		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))
		}
		jsonReq, err := m.Marshal(req)
		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/instanceGroups/%v/listInstances", req.GetProject(), req.GetZone(), req.GetInstanceGroup())

		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(), bytes.NewReader(jsonReq))
			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
}

// RemoveInstances removes one or more instances from the specified instance group, but does not delete those 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 before the VM instance is removed or deleted.
func (c *instanceGroupsRESTClient) RemoveInstances(ctx context.Context, req *computepb.RemoveInstancesInstanceGroupRequest, opts ...gax.CallOption) (*Operation, error) {
	m := protojson.MarshalOptions{AllowPartial: true}
	body := req.GetInstanceGroupsRemoveInstancesRequestResource()
	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/instanceGroups/%v/removeInstances", req.GetProject(), req.GetZone(), req.GetInstanceGroup())

	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", url.QueryEscape(req.GetInstanceGroup())))

	headers := buildHeaders(ctx, c.xGoogMetadata, md, metadata.Pairs("Content-Type", "application/json"))
	opts = append((*c.CallOptions).RemoveInstances[0:len((*c.CallOptions).RemoveInstances):len((*c.CallOptions).RemoveInstances)], 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
}

// SetNamedPorts sets the named ports for the specified instance group.
func (c *instanceGroupsRESTClient) SetNamedPorts(ctx context.Context, req *computepb.SetNamedPortsInstanceGroupRequest, opts ...gax.CallOption) (*Operation, error) {
	m := protojson.MarshalOptions{AllowPartial: true}
	body := req.GetInstanceGroupsSetNamedPortsRequestResource()
	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/instanceGroups/%v/setNamedPorts", req.GetProject(), req.GetZone(), req.GetInstanceGroup())

	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", url.QueryEscape(req.GetInstanceGroup())))

	headers := buildHeaders(ctx, c.xGoogMetadata, md, metadata.Pairs("Content-Type", "application/json"))
	opts = append((*c.CallOptions).SetNamedPorts[0:len((*c.CallOptions).SetNamedPorts):len((*c.CallOptions).SetNamedPorts)], 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
}

// InstanceGroupIterator manages a stream of *computepb.InstanceGroup.
type InstanceGroupIterator struct {
	items    []*computepb.InstanceGroup
	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.InstanceGroup, nextPageToken string, err error)
}

// PageInfo supports pagination. See the google.golang.org/api/iterator package for details.
func (it *InstanceGroupIterator) 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 *InstanceGroupIterator) Next() (*computepb.InstanceGroup, error) {
	var item *computepb.InstanceGroup
	if err := it.nextFunc(); err != nil {
		return item, err
	}
	item = it.items[0]
	it.items = it.items[1:]
	return item, nil
}

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

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

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

// InstanceGroupsScopedListPairIterator manages a stream of InstanceGroupsScopedListPair.
type InstanceGroupsScopedListPairIterator struct {
	items    []InstanceGroupsScopedListPair
	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 []InstanceGroupsScopedListPair, nextPageToken string, err error)
}

// PageInfo supports pagination. See the google.golang.org/api/iterator package for details.
func (it *InstanceGroupsScopedListPairIterator) 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 *InstanceGroupsScopedListPairIterator) Next() (InstanceGroupsScopedListPair, error) {
	var item InstanceGroupsScopedListPair
	if err := it.nextFunc(); err != nil {
		return item, err
	}
	item = it.items[0]
	it.items = it.items[1:]
	return item, nil
}

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

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

// InstanceWithNamedPortsIterator manages a stream of *computepb.InstanceWithNamedPorts.
type InstanceWithNamedPortsIterator struct {
	items    []*computepb.InstanceWithNamedPorts
	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.InstanceWithNamedPorts, nextPageToken string, err error)
}

// PageInfo supports pagination. See the google.golang.org/api/iterator package for details.
func (it *InstanceWithNamedPortsIterator) 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 *InstanceWithNamedPortsIterator) Next() (*computepb.InstanceWithNamedPorts, error) {
	var item *computepb.InstanceWithNamedPorts
	if err := it.nextFunc(); err != nil {
		return item, err
	}
	item = it.items[0]
	it.items = it.items[1:]
	return item, nil
}

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

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