discoveryengine/apiv1/project_client.go

// Copyright 2026 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 discoveryengine

import (
	"bytes"
	"context"
	"fmt"
	"log/slog"
	"math"
	"net/http"
	"net/url"
	"time"

	discoveryenginepb "cloud.google.com/go/discoveryengine/apiv1/discoveryenginepb"
	"cloud.google.com/go/longrunning"
	lroauto "cloud.google.com/go/longrunning/autogen"
	longrunningpb "cloud.google.com/go/longrunning/autogen/longrunningpb"
	gax "github.com/googleapis/gax-go/v2"
	"github.com/googleapis/gax-go/v2/callctx"
	trace "go.opentelemetry.io/otel/trace"
	"google.golang.org/api/iterator"
	"google.golang.org/api/option"
	"google.golang.org/api/option/internaloption"
	gtransport "google.golang.org/api/transport/grpc"
	httptransport "google.golang.org/api/transport/http"
	"google.golang.org/grpc"
	"google.golang.org/grpc/codes"
	"google.golang.org/protobuf/encoding/protojson"
	"google.golang.org/protobuf/proto"
)

var newProjectClientHook clientHook

// ProjectCallOptions contains the retry settings for each method of ProjectClient.
type ProjectCallOptions struct {
	ProvisionProject []gax.CallOption
	CancelOperation  []gax.CallOption
	GetOperation     []gax.CallOption
	ListOperations   []gax.CallOption
}

func defaultProjectGRPCClientOptions() []option.ClientOption {
	return []option.ClientOption{
		internaloption.WithDefaultEndpoint("discoveryengine.googleapis.com:443"),
		internaloption.WithDefaultEndpointTemplate("discoveryengine.UNIVERSE_DOMAIN:443"),
		internaloption.WithDefaultMTLSEndpoint("discoveryengine.mtls.googleapis.com:443"),
		internaloption.WithDefaultUniverseDomain("googleapis.com"),
		internaloption.WithDefaultAudience("https://discoveryengine.googleapis.com/"),
		internaloption.WithDefaultScopes(DefaultAuthScopes()...),
		internaloption.EnableJwtWithScope(),
		internaloption.EnableNewAuthLibrary(),
		option.WithGRPCDialOption(grpc.WithDefaultCallOptions(
			grpc.MaxCallRecvMsgSize(math.MaxInt32))),
	}
}

func defaultProjectCallOptions() *ProjectCallOptions {
	return &ProjectCallOptions{
		ProvisionProject: []gax.CallOption{
			gax.WithTimeout(30000 * time.Millisecond),
			gax.WithRetry(func() gax.Retryer {
				return gax.OnCodes([]codes.Code{
					codes.Unavailable,
				}, gax.Backoff{
					Initial:    1000 * time.Millisecond,
					Max:        10000 * time.Millisecond,
					Multiplier: 1.30,
				})
			}),
		},
		CancelOperation: []gax.CallOption{
			gax.WithTimeout(30000 * time.Millisecond),
			gax.WithRetry(func() gax.Retryer {
				return gax.OnCodes([]codes.Code{
					codes.Unavailable,
				}, gax.Backoff{
					Initial:    1000 * time.Millisecond,
					Max:        10000 * time.Millisecond,
					Multiplier: 1.30,
				})
			}),
		},
		GetOperation: []gax.CallOption{
			gax.WithTimeout(30000 * time.Millisecond),
			gax.WithRetry(func() gax.Retryer {
				return gax.OnCodes([]codes.Code{
					codes.Unavailable,
				}, gax.Backoff{
					Initial:    1000 * time.Millisecond,
					Max:        10000 * time.Millisecond,
					Multiplier: 1.30,
				})
			}),
		},
		ListOperations: []gax.CallOption{
			gax.WithTimeout(300000 * time.Millisecond),
			gax.WithRetry(func() gax.Retryer {
				return gax.OnCodes([]codes.Code{
					codes.Unavailable,
				}, gax.Backoff{
					Initial:    1000 * time.Millisecond,
					Max:        30000 * time.Millisecond,
					Multiplier: 1.30,
				})
			}),
		},
	}
}

func defaultProjectRESTCallOptions() *ProjectCallOptions {
	return &ProjectCallOptions{
		ProvisionProject: []gax.CallOption{
			gax.WithTimeout(30000 * time.Millisecond),
			gax.WithRetry(func() gax.Retryer {
				return gax.OnHTTPCodes(gax.Backoff{
					Initial:    1000 * time.Millisecond,
					Max:        10000 * time.Millisecond,
					Multiplier: 1.30,
				},
					http.StatusServiceUnavailable)
			}),
		},
		CancelOperation: []gax.CallOption{
			gax.WithTimeout(30000 * time.Millisecond),
			gax.WithRetry(func() gax.Retryer {
				return gax.OnHTTPCodes(gax.Backoff{
					Initial:    1000 * time.Millisecond,
					Max:        10000 * time.Millisecond,
					Multiplier: 1.30,
				},
					http.StatusServiceUnavailable)
			}),
		},
		GetOperation: []gax.CallOption{
			gax.WithTimeout(30000 * time.Millisecond),
			gax.WithRetry(func() gax.Retryer {
				return gax.OnHTTPCodes(gax.Backoff{
					Initial:    1000 * time.Millisecond,
					Max:        10000 * time.Millisecond,
					Multiplier: 1.30,
				},
					http.StatusServiceUnavailable)
			}),
		},
		ListOperations: []gax.CallOption{
			gax.WithTimeout(300000 * time.Millisecond),
			gax.WithRetry(func() gax.Retryer {
				return gax.OnHTTPCodes(gax.Backoff{
					Initial:    1000 * time.Millisecond,
					Max:        30000 * time.Millisecond,
					Multiplier: 1.30,
				},
					http.StatusServiceUnavailable)
			}),
		},
	}
}

// internalProjectClient is an interface that defines the methods available from Discovery Engine API.
type internalProjectClient interface {
	Close() error
	setGoogleClientInfo(...string)
	Connection() *grpc.ClientConn
	ProvisionProject(context.Context, *discoveryenginepb.ProvisionProjectRequest, ...gax.CallOption) (*ProvisionProjectOperation, error)
	ProvisionProjectOperation(name string) *ProvisionProjectOperation
	CancelOperation(context.Context, *longrunningpb.CancelOperationRequest, ...gax.CallOption) error
	GetOperation(context.Context, *longrunningpb.GetOperationRequest, ...gax.CallOption) (*longrunningpb.Operation, error)
	ListOperations(context.Context, *longrunningpb.ListOperationsRequest, ...gax.CallOption) *OperationIterator
}

// ProjectClient is a client for interacting with Discovery Engine API.
// Methods, except Close, may be called concurrently. However, fields must not be modified concurrently with method calls.
//
// Service for operations on the
// Project.
type ProjectClient struct {
	// The internal transport-dependent client.
	internalClient internalProjectClient

	// The call options for this service.
	CallOptions *ProjectCallOptions

	// LROClient is used internally to handle long-running operations.
	// It is exposed so that its CallOptions can be modified if required.
	// Users should not Close this client.
	LROClient *lroauto.OperationsClient
}

// Wrapper methods routed to the internal client.

// Close closes the connection to the API service. **Always** call Close() when
// the client is no longer required.
func (c *ProjectClient) 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 *ProjectClient) 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 *ProjectClient) Connection() *grpc.ClientConn {
	return c.internalClient.Connection()
}

// ProvisionProject provisions the project resource. During the
// process, related systems will get prepared and initialized.
//
// Caller must read the Terms for data
// use (at https://cloud.google.com/retail/data-use-terms), and optionally
// specify in request to provide consent to that service terms.
func (c *ProjectClient) ProvisionProject(ctx context.Context, req *discoveryenginepb.ProvisionProjectRequest, opts ...gax.CallOption) (*ProvisionProjectOperation, error) {
	return c.internalClient.ProvisionProject(ctx, req, opts...)
}

// ProvisionProjectOperation returns a new ProvisionProjectOperation from a given name.
// The name must be that of a previously created ProvisionProjectOperation, possibly from a different process.
func (c *ProjectClient) ProvisionProjectOperation(name string) *ProvisionProjectOperation {
	return c.internalClient.ProvisionProjectOperation(name)
}

// CancelOperation is a utility method from google.longrunning.Operations.
func (c *ProjectClient) CancelOperation(ctx context.Context, req *longrunningpb.CancelOperationRequest, opts ...gax.CallOption) error {
	return c.internalClient.CancelOperation(ctx, req, opts...)
}

// GetOperation is a utility method from google.longrunning.Operations.
func (c *ProjectClient) GetOperation(ctx context.Context, req *longrunningpb.GetOperationRequest, opts ...gax.CallOption) (*longrunningpb.Operation, error) {
	return c.internalClient.GetOperation(ctx, req, opts...)
}

// ListOperations is a utility method from google.longrunning.Operations.
func (c *ProjectClient) ListOperations(ctx context.Context, req *longrunningpb.ListOperationsRequest, opts ...gax.CallOption) *OperationIterator {
	return c.internalClient.ListOperations(ctx, req, opts...)
}

// projectGRPCClient is a client for interacting with Discovery Engine API over gRPC transport.
//
// Methods, except Close, may be called concurrently. However, fields must not be modified concurrently with method calls.
type projectGRPCClient struct {
	// Connection pool of gRPC connections to the service.
	connPool gtransport.ConnPool

	// Points back to the CallOptions field of the containing ProjectClient
	CallOptions **ProjectCallOptions

	// The gRPC API client.
	projectClient discoveryenginepb.ProjectServiceClient

	// LROClient is used internally to handle long-running operations.
	// It is exposed so that its CallOptions can be modified if required.
	// Users should not Close this client.
	LROClient **lroauto.OperationsClient

	operationsClient longrunningpb.OperationsClient

	// The x-goog-* metadata to be sent with each request.
	xGoogHeaders []string

	logger *slog.Logger
}

// NewProjectClient creates a new project service client based on gRPC.
// The returned client must be Closed when it is done being used to clean up its underlying connections.
//
// Service for operations on the
// Project.
func NewProjectClient(ctx context.Context, opts ...option.ClientOption) (*ProjectClient, error) {
	clientOpts := defaultProjectGRPCClientOptions()
	if gax.IsFeatureEnabled("TRACING") || gax.IsFeatureEnabled("LOGGING") {
		clientOpts = append(clientOpts, internaloption.WithTelemetryAttributes(map[string]string{
			"gcp.client.service":  "discoveryengine",
			"gcp.client.version":  getVersionClient(),
			"gcp.client.repo":     "googleapis/google-cloud-go",
			"gcp.client.artifact": "cloud.google.com/go/discoveryengine/apiv1",
			"gcp.client.language": "go",
			"url.domain":          "discoveryengine.googleapis.com",
		}))
	}
	if newProjectClientHook != nil {
		hookOpts, err := newProjectClientHook(ctx, clientHookParams{})
		if err != nil {
			return nil, err
		}
		clientOpts = append(clientOpts, hookOpts...)
	}

	connPool, err := gtransport.DialPool(ctx, append(clientOpts, opts...)...)
	if err != nil {
		return nil, err
	}
	client := ProjectClient{CallOptions: defaultProjectCallOptions()}

	c := &projectGRPCClient{
		connPool:         connPool,
		projectClient:    discoveryenginepb.NewProjectServiceClient(connPool),
		CallOptions:      &client.CallOptions,
		logger:           internaloption.GetLogger(opts),
		operationsClient: longrunningpb.NewOperationsClient(connPool),
	}
	c.setGoogleClientInfo()
	if gax.IsFeatureEnabled("METRICS") {
		metrics := gax.NewClientMetrics(
			gax.WithTelemetryLogger(c.logger),
			gax.WithTelemetryAttributes(map[string]string{
				gax.ClientService:  "discoveryengine",
				gax.ClientVersion:  getVersionClient(),
				gax.ClientArtifact: "cloud.google.com/go/discoveryengine/apiv1",
				gax.RPCSystem:      "grpc",
				gax.URLDomain:      "discoveryengine.googleapis.com",
			}),
		)

		client.CallOptions.ProvisionProject = append(client.CallOptions.ProvisionProject, gax.WithClientMetrics(metrics))
		client.CallOptions.CancelOperation = append(client.CallOptions.CancelOperation, gax.WithClientMetrics(metrics))
		client.CallOptions.GetOperation = append(client.CallOptions.GetOperation, gax.WithClientMetrics(metrics))
		client.CallOptions.ListOperations = append(client.CallOptions.ListOperations, gax.WithClientMetrics(metrics))
	}

	client.internalClient = c

	client.LROClient, err = lroauto.NewOperationsClient(ctx, gtransport.WithConnPool(connPool))
	if err != nil {
		// This error "should not happen", since we are just reusing old connection pool
		// and never actually need to dial.
		// If this does happen, we could leak connp. However, we cannot close conn:
		// If the user invoked the constructor with option.WithGRPCConn,
		// we would close a connection that's still in use.
		// TODO: investigate error conditions.
		return nil, err
	}
	c.LROClient = &client.LROClient
	return &client, nil
}

// 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 *projectGRPCClient) Connection() *grpc.ClientConn {
	return c.connPool.Conn()
}

// 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 *projectGRPCClient) setGoogleClientInfo(keyval ...string) {
	kv := append([]string{"gl-go", gax.GoVersion}, keyval...)
	kv = append(kv, "gapic", getVersionClient(), "gax", gax.Version, "grpc", grpc.Version, "pb", protoVersion)
	c.xGoogHeaders = []string{
		"x-goog-api-client", gax.XGoogHeader(kv...),
	}
}

// Close closes the connection to the API service. **Always** call Close() when
// the client is no longer required.
func (c *projectGRPCClient) Close() error {
	return c.connPool.Close()
}

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

	// The http client.
	httpClient *http.Client

	// LROClient is used internally to handle long-running operations.
	// It is exposed so that its CallOptions can be modified if required.
	// Users should not Close this client.
	LROClient **lroauto.OperationsClient

	// The x-goog-* headers to be sent with each request.
	xGoogHeaders []string

	// Points back to the CallOptions field of the containing ProjectClient
	CallOptions **ProjectCallOptions

	logger *slog.Logger
}

// NewProjectRESTClient creates a new project service rest client.
//
// Service for operations on the
// Project.
func NewProjectRESTClient(ctx context.Context, opts ...option.ClientOption) (*ProjectClient, error) {
	clientOpts := append(defaultProjectRESTClientOptions(), opts...)
	if gax.IsFeatureEnabled("TRACING") || gax.IsFeatureEnabled("LOGGING") {
		clientOpts = append(clientOpts, internaloption.WithTelemetryAttributes(map[string]string{
			"gcp.client.service":  "discoveryengine",
			"gcp.client.version":  getVersionClient(),
			"gcp.client.repo":     "googleapis/google-cloud-go",
			"gcp.client.artifact": "cloud.google.com/go/discoveryengine/apiv1",
			"gcp.client.language": "go",
			"url.domain":          "discoveryengine.googleapis.com",
		}))
	}
	httpClient, endpoint, err := httptransport.NewClient(ctx, clientOpts...)
	if err != nil {
		return nil, err
	}

	callOpts := defaultProjectRESTCallOptions()
	c := &projectRESTClient{
		endpoint:    endpoint,
		httpClient:  httpClient,
		CallOptions: &callOpts,
		logger:      internaloption.GetLogger(opts),
	}
	c.setGoogleClientInfo()

	if gax.IsFeatureEnabled("METRICS") {
		metrics := gax.NewClientMetrics(
			gax.WithTelemetryLogger(c.logger),
			gax.WithTelemetryAttributes(map[string]string{
				gax.ClientService:  "discoveryengine",
				gax.ClientVersion:  getVersionClient(),
				gax.ClientArtifact: "cloud.google.com/go/discoveryengine/apiv1",
				gax.RPCSystem:      "http",
				gax.URLDomain:      "discoveryengine.googleapis.com",
			}),
		)

		callOpts.ProvisionProject = append(callOpts.ProvisionProject, gax.WithClientMetrics(metrics))
		callOpts.CancelOperation = append(callOpts.CancelOperation, gax.WithClientMetrics(metrics))
		callOpts.GetOperation = append(callOpts.GetOperation, gax.WithClientMetrics(metrics))
		callOpts.ListOperations = append(callOpts.ListOperations, gax.WithClientMetrics(metrics))
	}

	lroOpts := []option.ClientOption{
		option.WithHTTPClient(httpClient),
		option.WithEndpoint(endpoint),
	}
	opClient, err := lroauto.NewOperationsRESTClient(ctx, lroOpts...)
	if err != nil {
		return nil, err
	}
	c.LROClient = &opClient

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

func defaultProjectRESTClientOptions() []option.ClientOption {
	return []option.ClientOption{
		internaloption.WithDefaultEndpoint("https://discoveryengine.googleapis.com"),
		internaloption.WithDefaultEndpointTemplate("https://discoveryengine.UNIVERSE_DOMAIN"),
		internaloption.WithDefaultMTLSEndpoint("https://discoveryengine.mtls.googleapis.com"),
		internaloption.WithDefaultUniverseDomain("googleapis.com"),
		internaloption.WithDefaultAudience("https://discoveryengine.googleapis.com/"),
		internaloption.WithDefaultScopes(DefaultAuthScopes()...),
		internaloption.EnableNewAuthLibrary(),
	}
}

// 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 *projectRESTClient) setGoogleClientInfo(keyval ...string) {
	kv := append([]string{"gl-go", gax.GoVersion}, keyval...)
	kv = append(kv, "gapic", getVersionClient(), "gax", gax.Version, "rest", "UNKNOWN", "pb", protoVersion)
	c.xGoogHeaders = []string{
		"x-goog-api-client", gax.XGoogHeader(kv...),
	}
}

// Close closes the connection to the API service. **Always** call Close() when
// the client is no longer required.
func (c *projectRESTClient) Close() error {
	// Replace httpClient with nil to force cleanup.
	c.httpClient = nil
	return nil
}

// Connection returns a connection to the API service.
//
// Deprecated: This method always returns nil.
func (c *projectRESTClient) Connection() *grpc.ClientConn {
	return nil
}
func (c *projectGRPCClient) ProvisionProject(ctx context.Context, req *discoveryenginepb.ProvisionProjectRequest, opts ...gax.CallOption) (*ProvisionProjectOperation, error) {
	hds := []string{"x-goog-request-params", fmt.Sprintf("%s=%v", "name", url.QueryEscape(req.GetName()))}

	hds = append(c.xGoogHeaders, hds...)
	ctx = gax.InsertMetadataIntoOutgoingContext(ctx, hds...)
	if gax.IsFeatureEnabled("TRACING") || gax.IsFeatureEnabled("LOGGING") {
		ctx = callctx.WithTelemetryContext(ctx, "resource_name", fmt.Sprintf("//discoveryengine.googleapis.com/%v", req.GetName()))
	}
	if gax.IsFeatureEnabled("METRICS") || gax.IsFeatureEnabled("TRACING") || gax.IsFeatureEnabled("LOGGING") {
		ctx = callctx.WithTelemetryContext(ctx, "rpc_method", "google.cloud.discoveryengine.v1.ProjectService/ProvisionProject")
	}
	opts = append((*c.CallOptions).ProvisionProject[0:len((*c.CallOptions).ProvisionProject):len((*c.CallOptions).ProvisionProject)], opts...)
	var resp *longrunningpb.Operation
	err := gax.Invoke(ctx, func(ctx context.Context, settings gax.CallSettings) error {
		var err error
		resp, err = executeRPC(ctx, c.projectClient.ProvisionProject, req, settings.GRPC, c.logger, "ProvisionProject")
		return err
	}, opts...)
	if err != nil {
		return nil, err
	}
	lro := longrunning.InternalNewOperationWithMetadata(*c.LROClient, resp, "*discoveryengine.ProvisionProjectOperation")
	if gax.IsFeatureEnabled("TRACING") {
		lro.SetParentSpanContext(trace.SpanContextFromContext(ctx))
	}
	return &ProvisionProjectOperation{
		lro: lro,
	}, nil
}

func (c *projectGRPCClient) CancelOperation(ctx context.Context, req *longrunningpb.CancelOperationRequest, opts ...gax.CallOption) error {
	hds := []string{"x-goog-request-params", fmt.Sprintf("%s=%v", "name", url.QueryEscape(req.GetName()))}

	hds = append(c.xGoogHeaders, hds...)
	ctx = gax.InsertMetadataIntoOutgoingContext(ctx, hds...)
	if gax.IsFeatureEnabled("METRICS") || gax.IsFeatureEnabled("TRACING") || gax.IsFeatureEnabled("LOGGING") {
		ctx = callctx.WithTelemetryContext(ctx, "rpc_method", "google.longrunning.Operations/CancelOperation")
	}
	opts = append((*c.CallOptions).CancelOperation[0:len((*c.CallOptions).CancelOperation):len((*c.CallOptions).CancelOperation)], opts...)
	err := gax.Invoke(ctx, func(ctx context.Context, settings gax.CallSettings) error {
		var err error
		_, err = executeRPC(ctx, c.operationsClient.CancelOperation, req, settings.GRPC, c.logger, "CancelOperation")
		return err
	}, opts...)
	return err
}

func (c *projectGRPCClient) GetOperation(ctx context.Context, req *longrunningpb.GetOperationRequest, opts ...gax.CallOption) (*longrunningpb.Operation, error) {
	hds := []string{"x-goog-request-params", fmt.Sprintf("%s=%v", "name", url.QueryEscape(req.GetName()))}

	hds = append(c.xGoogHeaders, hds...)
	ctx = gax.InsertMetadataIntoOutgoingContext(ctx, hds...)
	if gax.IsFeatureEnabled("METRICS") || gax.IsFeatureEnabled("TRACING") || gax.IsFeatureEnabled("LOGGING") {
		ctx = callctx.WithTelemetryContext(ctx, "rpc_method", "google.longrunning.Operations/GetOperation")
	}
	opts = append((*c.CallOptions).GetOperation[0:len((*c.CallOptions).GetOperation):len((*c.CallOptions).GetOperation)], opts...)
	var resp *longrunningpb.Operation
	err := gax.Invoke(ctx, func(ctx context.Context, settings gax.CallSettings) error {
		var err error
		resp, err = executeRPC(ctx, c.operationsClient.GetOperation, req, settings.GRPC, c.logger, "GetOperation")
		return err
	}, opts...)
	if err != nil {
		return nil, err
	}
	return resp, nil
}

func (c *projectGRPCClient) ListOperations(ctx context.Context, req *longrunningpb.ListOperationsRequest, opts ...gax.CallOption) *OperationIterator {
	hds := []string{"x-goog-request-params", fmt.Sprintf("%s=%v", "name", url.QueryEscape(req.GetName()))}

	hds = append(c.xGoogHeaders, hds...)
	ctx = gax.InsertMetadataIntoOutgoingContext(ctx, hds...)
	if gax.IsFeatureEnabled("METRICS") || gax.IsFeatureEnabled("TRACING") || gax.IsFeatureEnabled("LOGGING") {
		ctx = callctx.WithTelemetryContext(ctx, "rpc_method", "google.longrunning.Operations/ListOperations")
	}
	opts = append((*c.CallOptions).ListOperations[0:len((*c.CallOptions).ListOperations):len((*c.CallOptions).ListOperations)], opts...)
	it := &OperationIterator{}
	req = proto.CloneOf(req)
	it.InternalFetch = func(pageSize int, pageToken string) ([]*longrunningpb.Operation, string, error) {
		resp := &longrunningpb.ListOperationsResponse{}
		if pageToken != "" {
			req.PageToken = pageToken
		}
		if pageSize > math.MaxInt32 {
			req.PageSize = math.MaxInt32
		} else if pageSize != 0 {
			req.PageSize = int32(pageSize)
		}
		err := gax.Invoke(ctx, func(ctx context.Context, settings gax.CallSettings) error {
			var err error
			resp, err = executeRPC(ctx, c.operationsClient.ListOperations, req, settings.GRPC, c.logger, "ListOperations")
			return err
		}, opts...)
		if err != nil {
			return nil, "", err
		}

		it.Response = resp
		return resp.GetOperations(), 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.GetPageSize())
	it.pageInfo.Token = req.GetPageToken()

	return it
}

// ProvisionProject provisions the project resource. During the
// process, related systems will get prepared and initialized.
//
// Caller must read the Terms for data
// use (at https://cloud.google.com/retail/data-use-terms), and optionally
// specify in request to provide consent to that service terms.
func (c *projectRESTClient) ProvisionProject(ctx context.Context, req *discoveryenginepb.ProvisionProjectRequest, opts ...gax.CallOption) (*ProvisionProjectOperation, error) {
	m := protojson.MarshalOptions{AllowPartial: true, UseEnumNumbers: true}
	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("/v1/%v:provision", req.GetName())

	params := url.Values{}
	params.Add("$alt", "json;enum-encoding=int")

	baseUrl.RawQuery = params.Encode()

	// Build HTTP headers from client and context metadata.
	hds := []string{"x-goog-request-params", fmt.Sprintf("%s=%v", "name", url.QueryEscape(req.GetName()))}

	hds = append(c.xGoogHeaders, hds...)
	hds = append(hds, "Content-Type", "application/json")
	headers := gax.BuildHeaders(ctx, hds...)
	if gax.IsFeatureEnabled("TRACING") || gax.IsFeatureEnabled("LOGGING") {
		ctx = callctx.WithTelemetryContext(ctx, "resource_name", fmt.Sprintf("//discoveryengine.googleapis.com/%v", req.GetName()))
	}
	if gax.IsFeatureEnabled("METRICS") || gax.IsFeatureEnabled("TRACING") || gax.IsFeatureEnabled("LOGGING") {
		ctx = callctx.WithTelemetryContext(ctx, "rpc_method", "google.cloud.discoveryengine.v1.ProjectService/ProvisionProject")
		ctx = callctx.WithTelemetryContext(ctx, "url_template", "/v1/{name=projects/*}:provision")
	}
	unm := protojson.UnmarshalOptions{AllowPartial: true, DiscardUnknown: true}
	resp := &longrunningpb.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

		buf, err := executeHTTPRequest(ctx, c.httpClient, httpReq, c.logger, jsonReq, "ProvisionProject")
		if err != nil {
			return err
		}
		if err := unm.Unmarshal(buf, resp); err != nil {
			return err
		}

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

	override := fmt.Sprintf("/v1/%s", resp.GetName())
	lro := longrunning.InternalNewOperationWithMetadata(*c.LROClient, resp, "*discoveryengine.ProvisionProjectOperation")
	if gax.IsFeatureEnabled("TRACING") {
		lro.SetParentSpanContext(trace.SpanContextFromContext(ctx))
	}
	return &ProvisionProjectOperation{
		lro:      lro,
		pollPath: override,
	}, nil
}

// CancelOperation is a utility method from google.longrunning.Operations.
func (c *projectRESTClient) CancelOperation(ctx context.Context, req *longrunningpb.CancelOperationRequest, opts ...gax.CallOption) error {
	m := protojson.MarshalOptions{AllowPartial: true, UseEnumNumbers: true}
	jsonReq, err := m.Marshal(req)
	if err != nil {
		return err
	}

	baseUrl, err := url.Parse(c.endpoint)
	if err != nil {
		return err
	}
	baseUrl.Path += fmt.Sprintf("/v1/%v:cancel", req.GetName())

	params := url.Values{}
	params.Add("$alt", "json;enum-encoding=int")

	baseUrl.RawQuery = params.Encode()

	// Build HTTP headers from client and context metadata.
	hds := []string{"x-goog-request-params", fmt.Sprintf("%s=%v", "name", url.QueryEscape(req.GetName()))}

	hds = append(c.xGoogHeaders, hds...)
	hds = append(hds, "Content-Type", "application/json")
	headers := gax.BuildHeaders(ctx, hds...)
	if gax.IsFeatureEnabled("METRICS") || gax.IsFeatureEnabled("TRACING") || gax.IsFeatureEnabled("LOGGING") {
		ctx = callctx.WithTelemetryContext(ctx, "rpc_method", "google.longrunning.Operations/CancelOperation")
		ctx = callctx.WithTelemetryContext(ctx, "url_template", "/v1/{name=projects/*/operations/*}:cancel")
	}
	return 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

		_, err = executeHTTPRequest(ctx, c.httpClient, httpReq, c.logger, jsonReq, "CancelOperation")
		return err
	}, opts...)
}

// GetOperation is a utility method from google.longrunning.Operations.
func (c *projectRESTClient) GetOperation(ctx context.Context, req *longrunningpb.GetOperationRequest, opts ...gax.CallOption) (*longrunningpb.Operation, error) {
	baseUrl, err := url.Parse(c.endpoint)
	if err != nil {
		return nil, err
	}
	baseUrl.Path += fmt.Sprintf("/v1/%v", req.GetName())

	params := url.Values{}
	params.Add("$alt", "json;enum-encoding=int")

	baseUrl.RawQuery = params.Encode()

	// Build HTTP headers from client and context metadata.
	hds := []string{"x-goog-request-params", fmt.Sprintf("%s=%v", "name", url.QueryEscape(req.GetName()))}

	hds = append(c.xGoogHeaders, hds...)
	hds = append(hds, "Content-Type", "application/json")
	headers := gax.BuildHeaders(ctx, hds...)
	if gax.IsFeatureEnabled("METRICS") || gax.IsFeatureEnabled("TRACING") || gax.IsFeatureEnabled("LOGGING") {
		ctx = callctx.WithTelemetryContext(ctx, "rpc_method", "google.longrunning.Operations/GetOperation")
		ctx = callctx.WithTelemetryContext(ctx, "url_template", "/v1/{name=projects/*/operations/*}")
	}
	opts = append((*c.CallOptions).GetOperation[0:len((*c.CallOptions).GetOperation):len((*c.CallOptions).GetOperation)], opts...)
	unm := protojson.UnmarshalOptions{AllowPartial: true, DiscardUnknown: true}
	resp := &longrunningpb.Operation{}
	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

		buf, err := executeHTTPRequest(ctx, c.httpClient, httpReq, c.logger, nil, "GetOperation")
		if err != nil {
			return err
		}

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

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

// ListOperations is a utility method from google.longrunning.Operations.
func (c *projectRESTClient) ListOperations(ctx context.Context, req *longrunningpb.ListOperationsRequest, opts ...gax.CallOption) *OperationIterator {
	it := &OperationIterator{}
	req = proto.CloneOf(req)
	unm := protojson.UnmarshalOptions{AllowPartial: true, DiscardUnknown: true}
	it.InternalFetch = func(pageSize int, pageToken string) ([]*longrunningpb.Operation, string, error) {
		resp := &longrunningpb.ListOperationsResponse{}
		if pageToken != "" {
			req.PageToken = pageToken
		}
		if pageSize > math.MaxInt32 {
			req.PageSize = math.MaxInt32
		} else if pageSize != 0 {
			req.PageSize = int32(pageSize)
		}
		baseUrl, err := url.Parse(c.endpoint)
		if err != nil {
			return nil, "", err
		}
		baseUrl.Path += fmt.Sprintf("/v1/%v/operations", req.GetName())

		params := url.Values{}
		params.Add("$alt", "json;enum-encoding=int")
		if req.GetFilter() != "" {
			params.Add("filter", fmt.Sprintf("%v", req.GetFilter()))
		}
		if req.GetPageSize() != 0 {
			params.Add("pageSize", fmt.Sprintf("%v", req.GetPageSize()))
		}
		if req.GetPageToken() != "" {
			params.Add("pageToken", fmt.Sprintf("%v", req.GetPageToken()))
		}
		if req.GetReturnPartialSuccess() {
			params.Add("returnPartialSuccess", fmt.Sprintf("%v", req.GetReturnPartialSuccess()))
		}

		baseUrl.RawQuery = params.Encode()

		// Build HTTP headers from client and context metadata.
		hds := append(c.xGoogHeaders, "Content-Type", "application/json")
		headers := gax.BuildHeaders(ctx, hds...)
		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

			buf, err := executeHTTPRequest(ctx, c.httpClient, httpReq, c.logger, nil, "ListOperations")
			if err != nil {
				return err
			}
			if err := unm.Unmarshal(buf, resp); err != nil {
				return err
			}

			return nil
		}, opts...)
		if e != nil {
			return nil, "", e
		}
		it.Response = resp
		return resp.GetOperations(), 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.GetPageSize())
	it.pageInfo.Token = req.GetPageToken()

	return it
}

// ProvisionProjectOperation returns a new ProvisionProjectOperation from a given name.
// The name must be that of a previously created ProvisionProjectOperation, possibly from a different process.
func (c *projectGRPCClient) ProvisionProjectOperation(name string) *ProvisionProjectOperation {
	return &ProvisionProjectOperation{
		lro: longrunning.InternalNewOperationWithMetadata(*c.LROClient, &longrunningpb.Operation{Name: name}, "*discoveryengine.ProvisionProjectOperation"),
	}
}

// ProvisionProjectOperation returns a new ProvisionProjectOperation from a given name.
// The name must be that of a previously created ProvisionProjectOperation, possibly from a different process.
func (c *projectRESTClient) ProvisionProjectOperation(name string) *ProvisionProjectOperation {
	override := fmt.Sprintf("/v1/%s", name)
	return &ProvisionProjectOperation{
		lro:      longrunning.InternalNewOperationWithMetadata(*c.LROClient, &longrunningpb.Operation{Name: name}, "*discoveryengine.ProvisionProjectOperation"),
		pollPath: override,
	}
}