// Copyright 2022 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"

	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"
	computepb "google.golang.org/genproto/googleapis/cloud/compute/v1"
	"google.golang.org/grpc"
	"google.golang.org/grpc/metadata"
	"google.golang.org/protobuf/encoding/protojson"
	"google.golang.org/protobuf/proto"
)

var newRegionHealthChecksClientHook clientHook

// RegionHealthChecksCallOptions contains the retry settings for each method of RegionHealthChecksClient.
type RegionHealthChecksCallOptions struct {
	Delete []gax.CallOption
	Get    []gax.CallOption
	Insert []gax.CallOption
	List   []gax.CallOption
	Patch  []gax.CallOption
	Update []gax.CallOption
}

func defaultRegionHealthChecksRESTCallOptions() *RegionHealthChecksCallOptions {
	return &RegionHealthChecksCallOptions{
		Delete: []gax.CallOption{},
		Get:    []gax.CallOption{},
		Insert: []gax.CallOption{},
		List:   []gax.CallOption{},
		Patch:  []gax.CallOption{},
		Update: []gax.CallOption{},
	}
}

// internalRegionHealthChecksClient is an interface that defines the methods available from Google Compute Engine API.
type internalRegionHealthChecksClient interface {
	Close() error
	setGoogleClientInfo(...string)
	Connection() *grpc.ClientConn
	Delete(context.Context, *computepb.DeleteRegionHealthCheckRequest, ...gax.CallOption) (*Operation, error)
	Get(context.Context, *computepb.GetRegionHealthCheckRequest, ...gax.CallOption) (*computepb.HealthCheck, error)
	Insert(context.Context, *computepb.InsertRegionHealthCheckRequest, ...gax.CallOption) (*Operation, error)
	List(context.Context, *computepb.ListRegionHealthChecksRequest, ...gax.CallOption) *HealthCheckIterator
	Patch(context.Context, *computepb.PatchRegionHealthCheckRequest, ...gax.CallOption) (*Operation, error)
	Update(context.Context, *computepb.UpdateRegionHealthCheckRequest, ...gax.CallOption) (*Operation, error)
}

// RegionHealthChecksClient 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 RegionHealthChecks API.
type RegionHealthChecksClient struct {
	// The internal transport-dependent client.
	internalClient internalRegionHealthChecksClient

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

// 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 *RegionHealthChecksClient) 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 *RegionHealthChecksClient) setGoogleClientInfo(keyval ...string) {
	c.internalClient.setGoogleClientInfo(keyval...)
}

// Connection returns a connection to the API service.
//
// Deprecated.
func (c *RegionHealthChecksClient) Connection() *grpc.ClientConn {
	return c.internalClient.Connection()
}

// Delete deletes the specified HealthCheck resource.
func (c *RegionHealthChecksClient) Delete(ctx context.Context, req *computepb.DeleteRegionHealthCheckRequest, opts ...gax.CallOption) (*Operation, error) {
	return c.internalClient.Delete(ctx, req, opts...)
}

// Get returns the specified HealthCheck resource. Gets a list of available health checks by making a list() request.
func (c *RegionHealthChecksClient) Get(ctx context.Context, req *computepb.GetRegionHealthCheckRequest, opts ...gax.CallOption) (*computepb.HealthCheck, error) {
	return c.internalClient.Get(ctx, req, opts...)
}

// Insert creates a HealthCheck resource in the specified project using the data included in the request.
func (c *RegionHealthChecksClient) Insert(ctx context.Context, req *computepb.InsertRegionHealthCheckRequest, opts ...gax.CallOption) (*Operation, error) {
	return c.internalClient.Insert(ctx, req, opts...)
}

// List retrieves the list of HealthCheck resources available to the specified project.
func (c *RegionHealthChecksClient) List(ctx context.Context, req *computepb.ListRegionHealthChecksRequest, opts ...gax.CallOption) *HealthCheckIterator {
	return c.internalClient.List(ctx, req, opts...)
}

// Patch updates a HealthCheck resource in the specified project using the data included in the request. This method supports PATCH semantics and uses the JSON merge patch format and processing rules.
func (c *RegionHealthChecksClient) Patch(ctx context.Context, req *computepb.PatchRegionHealthCheckRequest, opts ...gax.CallOption) (*Operation, error) {
	return c.internalClient.Patch(ctx, req, opts...)
}

// Update updates a HealthCheck resource in the specified project using the data included in the request.
func (c *RegionHealthChecksClient) Update(ctx context.Context, req *computepb.UpdateRegionHealthCheckRequest, opts ...gax.CallOption) (*Operation, error) {
	return c.internalClient.Update(ctx, req, opts...)
}

// Methods, except Close, may be called concurrently. However, fields must not be modified concurrently with method calls.
type regionHealthChecksRESTClient 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 *RegionOperationsClient

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

	// Points back to the CallOptions field of the containing RegionHealthChecksClient
	CallOptions **RegionHealthChecksCallOptions
}

// NewRegionHealthChecksRESTClient creates a new region health checks rest client.
//
// The RegionHealthChecks API.
func NewRegionHealthChecksRESTClient(ctx context.Context, opts ...option.ClientOption) (*RegionHealthChecksClient, error) {
	clientOpts := append(defaultRegionHealthChecksRESTClientOptions(), opts...)
	httpClient, endpoint, err := httptransport.NewClient(ctx, clientOpts...)
	if err != nil {
		return nil, err
	}

	callOpts := defaultRegionHealthChecksRESTCallOptions()
	c := &regionHealthChecksRESTClient{
		endpoint:    endpoint,
		httpClient:  httpClient,
		CallOptions: &callOpts,
	}
	c.setGoogleClientInfo()

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

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

func defaultRegionHealthChecksRESTClientOptions() []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 *regionHealthChecksRESTClient) 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 *regionHealthChecksRESTClient) 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.
func (c *regionHealthChecksRESTClient) Connection() *grpc.ClientConn {
	return nil
}

// Delete deletes the specified HealthCheck resource.
func (c *regionHealthChecksRESTClient) Delete(ctx context.Context, req *computepb.DeleteRegionHealthCheckRequest, 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/regions/%v/healthChecks/%v", req.GetProject(), req.GetRegion(), req.GetHealthCheck())

	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()), "region", url.QueryEscape(req.GetRegion()), "health_check", url.QueryEscape(req.GetHealthCheck())))

	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{
		&regionOperationsHandle{
			c:       c.operationClient,
			proto:   resp,
			project: req.GetProject(),
			region:  req.GetRegion(),
		},
	}
	return op, nil
}

// Get returns the specified HealthCheck resource. Gets a list of available health checks by making a list() request.
func (c *regionHealthChecksRESTClient) Get(ctx context.Context, req *computepb.GetRegionHealthCheckRequest, opts ...gax.CallOption) (*computepb.HealthCheck, error) {
	baseUrl, err := url.Parse(c.endpoint)
	if err != nil {
		return nil, err
	}
	baseUrl.Path += fmt.Sprintf("/compute/v1/projects/%v/regions/%v/healthChecks/%v", req.GetProject(), req.GetRegion(), req.GetHealthCheck())

	// 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()), "region", url.QueryEscape(req.GetRegion()), "health_check", url.QueryEscape(req.GetHealthCheck())))

	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.HealthCheck{}
	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 HealthCheck resource in the specified project using the data included in the request.
func (c *regionHealthChecksRESTClient) Insert(ctx context.Context, req *computepb.InsertRegionHealthCheckRequest, opts ...gax.CallOption) (*Operation, error) {
	m := protojson.MarshalOptions{AllowPartial: true}
	body := req.GetHealthCheckResource()
	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/regions/%v/healthChecks", req.GetProject(), req.GetRegion())

	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()), "region", url.QueryEscape(req.GetRegion())))

	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{
		&regionOperationsHandle{
			c:       c.operationClient,
			proto:   resp,
			project: req.GetProject(),
			region:  req.GetRegion(),
		},
	}
	return op, nil
}

// List retrieves the list of HealthCheck resources available to the specified project.
func (c *regionHealthChecksRESTClient) List(ctx context.Context, req *computepb.ListRegionHealthChecksRequest, opts ...gax.CallOption) *HealthCheckIterator {
	it := &HealthCheckIterator{}
	req = proto.Clone(req).(*computepb.ListRegionHealthChecksRequest)
	unm := protojson.UnmarshalOptions{AllowPartial: true, DiscardUnknown: true}
	it.InternalFetch = func(pageSize int, pageToken string) ([]*computepb.HealthCheck, string, error) {
		resp := &computepb.HealthCheckList{}
		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/regions/%v/healthChecks", req.GetProject(), req.GetRegion())

		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
}

// Patch updates a HealthCheck resource in the specified project using the data included in the request. This method supports PATCH semantics and uses the JSON merge patch format and processing rules.
func (c *regionHealthChecksRESTClient) Patch(ctx context.Context, req *computepb.PatchRegionHealthCheckRequest, opts ...gax.CallOption) (*Operation, error) {
	m := protojson.MarshalOptions{AllowPartial: true}
	body := req.GetHealthCheckResource()
	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/regions/%v/healthChecks/%v", req.GetProject(), req.GetRegion(), req.GetHealthCheck())

	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()), "region", url.QueryEscape(req.GetRegion()), "health_check", url.QueryEscape(req.GetHealthCheck())))

	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{
		&regionOperationsHandle{
			c:       c.operationClient,
			proto:   resp,
			project: req.GetProject(),
			region:  req.GetRegion(),
		},
	}
	return op, nil
}

// Update updates a HealthCheck resource in the specified project using the data included in the request.
func (c *regionHealthChecksRESTClient) Update(ctx context.Context, req *computepb.UpdateRegionHealthCheckRequest, opts ...gax.CallOption) (*Operation, error) {
	m := protojson.MarshalOptions{AllowPartial: true}
	body := req.GetHealthCheckResource()
	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/regions/%v/healthChecks/%v", req.GetProject(), req.GetRegion(), req.GetHealthCheck())

	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()), "region", url.QueryEscape(req.GetRegion()), "health_check", url.QueryEscape(req.GetHealthCheck())))

	headers := buildHeaders(ctx, c.xGoogMetadata, md, metadata.Pairs("Content-Type", "application/json"))
	opts = append((*c.CallOptions).Update[0:len((*c.CallOptions).Update):len((*c.CallOptions).Update)], 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("PUT", 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{
		&regionOperationsHandle{
			c:       c.operationClient,
			proto:   resp,
			project: req.GetProject(),
			region:  req.GetRegion(),
		},
	}
	return op, nil
}