dialogflow/apiv2/documents_client.go

// 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 dialogflow

import (
	"context"
	"fmt"
	"math"
	"net/url"
	"time"

	"cloud.google.com/go/longrunning"
	lroauto "cloud.google.com/go/longrunning/autogen"
	gax "github.com/googleapis/gax-go/v2"
	"google.golang.org/api/iterator"
	"google.golang.org/api/option"
	"google.golang.org/api/option/internaloption"
	gtransport "google.golang.org/api/transport/grpc"
	dialogflowpb "google.golang.org/genproto/googleapis/cloud/dialogflow/v2"
	locationpb "google.golang.org/genproto/googleapis/cloud/location"
	longrunningpb "google.golang.org/genproto/googleapis/longrunning"
	"google.golang.org/grpc"
	"google.golang.org/grpc/codes"
	"google.golang.org/grpc/metadata"
	"google.golang.org/protobuf/proto"
)

var newDocumentsClientHook clientHook

// DocumentsCallOptions contains the retry settings for each method of DocumentsClient.
type DocumentsCallOptions struct {
	ListDocuments   []gax.CallOption
	GetDocument     []gax.CallOption
	CreateDocument  []gax.CallOption
	ImportDocuments []gax.CallOption
	DeleteDocument  []gax.CallOption
	UpdateDocument  []gax.CallOption
	ReloadDocument  []gax.CallOption
	ExportDocument  []gax.CallOption
	GetLocation     []gax.CallOption
	ListLocations   []gax.CallOption
	CancelOperation []gax.CallOption
	GetOperation    []gax.CallOption
	ListOperations  []gax.CallOption
}

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

func defaultDocumentsCallOptions() *DocumentsCallOptions {
	return &DocumentsCallOptions{
		ListDocuments: []gax.CallOption{
			gax.WithRetry(func() gax.Retryer {
				return gax.OnCodes([]codes.Code{
					codes.Unavailable,
				}, gax.Backoff{
					Initial:    100 * time.Millisecond,
					Max:        60000 * time.Millisecond,
					Multiplier: 1.30,
				})
			}),
		},
		GetDocument: []gax.CallOption{
			gax.WithRetry(func() gax.Retryer {
				return gax.OnCodes([]codes.Code{
					codes.Unavailable,
				}, gax.Backoff{
					Initial:    100 * time.Millisecond,
					Max:        60000 * time.Millisecond,
					Multiplier: 1.30,
				})
			}),
		},
		CreateDocument: []gax.CallOption{
			gax.WithRetry(func() gax.Retryer {
				return gax.OnCodes([]codes.Code{
					codes.Unavailable,
				}, gax.Backoff{
					Initial:    100 * time.Millisecond,
					Max:        60000 * time.Millisecond,
					Multiplier: 1.30,
				})
			}),
		},
		ImportDocuments: []gax.CallOption{
			gax.WithRetry(func() gax.Retryer {
				return gax.OnCodes([]codes.Code{
					codes.Unavailable,
				}, gax.Backoff{
					Initial:    100 * time.Millisecond,
					Max:        60000 * time.Millisecond,
					Multiplier: 1.30,
				})
			}),
		},
		DeleteDocument: []gax.CallOption{
			gax.WithRetry(func() gax.Retryer {
				return gax.OnCodes([]codes.Code{
					codes.Unavailable,
				}, gax.Backoff{
					Initial:    100 * time.Millisecond,
					Max:        60000 * time.Millisecond,
					Multiplier: 1.30,
				})
			}),
		},
		UpdateDocument: []gax.CallOption{
			gax.WithRetry(func() gax.Retryer {
				return gax.OnCodes([]codes.Code{
					codes.Unavailable,
				}, gax.Backoff{
					Initial:    100 * time.Millisecond,
					Max:        60000 * time.Millisecond,
					Multiplier: 1.30,
				})
			}),
		},
		ReloadDocument: []gax.CallOption{
			gax.WithRetry(func() gax.Retryer {
				return gax.OnCodes([]codes.Code{
					codes.Unavailable,
				}, gax.Backoff{
					Initial:    100 * time.Millisecond,
					Max:        60000 * time.Millisecond,
					Multiplier: 1.30,
				})
			}),
		},
		ExportDocument: []gax.CallOption{
			gax.WithRetry(func() gax.Retryer {
				return gax.OnCodes([]codes.Code{
					codes.Unavailable,
				}, gax.Backoff{
					Initial:    100 * time.Millisecond,
					Max:        60000 * time.Millisecond,
					Multiplier: 1.30,
				})
			}),
		},
		GetLocation:     []gax.CallOption{},
		ListLocations:   []gax.CallOption{},
		CancelOperation: []gax.CallOption{},
		GetOperation:    []gax.CallOption{},
		ListOperations:  []gax.CallOption{},
	}
}

// internalDocumentsClient is an interface that defines the methods available from Dialogflow API.
type internalDocumentsClient interface {
	Close() error
	setGoogleClientInfo(...string)
	Connection() *grpc.ClientConn
	ListDocuments(context.Context, *dialogflowpb.ListDocumentsRequest, ...gax.CallOption) *DocumentIterator
	GetDocument(context.Context, *dialogflowpb.GetDocumentRequest, ...gax.CallOption) (*dialogflowpb.Document, error)
	CreateDocument(context.Context, *dialogflowpb.CreateDocumentRequest, ...gax.CallOption) (*CreateDocumentOperation, error)
	CreateDocumentOperation(name string) *CreateDocumentOperation
	ImportDocuments(context.Context, *dialogflowpb.ImportDocumentsRequest, ...gax.CallOption) (*ImportDocumentsOperation, error)
	ImportDocumentsOperation(name string) *ImportDocumentsOperation
	DeleteDocument(context.Context, *dialogflowpb.DeleteDocumentRequest, ...gax.CallOption) (*DeleteDocumentOperation, error)
	DeleteDocumentOperation(name string) *DeleteDocumentOperation
	UpdateDocument(context.Context, *dialogflowpb.UpdateDocumentRequest, ...gax.CallOption) (*UpdateDocumentOperation, error)
	UpdateDocumentOperation(name string) *UpdateDocumentOperation
	ReloadDocument(context.Context, *dialogflowpb.ReloadDocumentRequest, ...gax.CallOption) (*ReloadDocumentOperation, error)
	ReloadDocumentOperation(name string) *ReloadDocumentOperation
	ExportDocument(context.Context, *dialogflowpb.ExportDocumentRequest, ...gax.CallOption) (*ExportDocumentOperation, error)
	ExportDocumentOperation(name string) *ExportDocumentOperation
	GetLocation(context.Context, *locationpb.GetLocationRequest, ...gax.CallOption) (*locationpb.Location, error)
	ListLocations(context.Context, *locationpb.ListLocationsRequest, ...gax.CallOption) *LocationIterator
	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
}

// DocumentsClient is a client for interacting with Dialogflow API.
// Methods, except Close, may be called concurrently. However, fields must not be modified concurrently with method calls.
//
// Service for managing knowledge Documents.
type DocumentsClient struct {
	// The internal transport-dependent client.
	internalClient internalDocumentsClient

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

	// 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. The user should invoke this when
// the client is no longer required.
func (c *DocumentsClient) 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 *DocumentsClient) setGoogleClientInfo(keyval ...string) {
	c.internalClient.setGoogleClientInfo(keyval...)
}

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

// ListDocuments returns the list of all documents of the knowledge base.
func (c *DocumentsClient) ListDocuments(ctx context.Context, req *dialogflowpb.ListDocumentsRequest, opts ...gax.CallOption) *DocumentIterator {
	return c.internalClient.ListDocuments(ctx, req, opts...)
}

// GetDocument retrieves the specified document.
func (c *DocumentsClient) GetDocument(ctx context.Context, req *dialogflowpb.GetDocumentRequest, opts ...gax.CallOption) (*dialogflowpb.Document, error) {
	return c.internalClient.GetDocument(ctx, req, opts...)
}

// CreateDocument creates a new document.
//
// This method is a long-running
// operation (at https://cloud.google.com/dialogflow/cx/docs/how/long-running-operation).
// The returned Operation type has the following method-specific fields:
//
//   metadata: KnowledgeOperationMetadata
//
//   response: Document
func (c *DocumentsClient) CreateDocument(ctx context.Context, req *dialogflowpb.CreateDocumentRequest, opts ...gax.CallOption) (*CreateDocumentOperation, error) {
	return c.internalClient.CreateDocument(ctx, req, opts...)
}

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

// ImportDocuments creates documents by importing data from external sources.
// Dialogflow supports up to 350 documents in each request. If you try to
// import more, Dialogflow will return an error.
//
// This method is a long-running
// operation (at https://cloud.google.com/dialogflow/cx/docs/how/long-running-operation).
// The returned Operation type has the following method-specific fields:
//
//   metadata: KnowledgeOperationMetadata
//
//   response: ImportDocumentsResponse
func (c *DocumentsClient) ImportDocuments(ctx context.Context, req *dialogflowpb.ImportDocumentsRequest, opts ...gax.CallOption) (*ImportDocumentsOperation, error) {
	return c.internalClient.ImportDocuments(ctx, req, opts...)
}

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

// DeleteDocument deletes the specified document.
//
// This method is a long-running
// operation (at https://cloud.google.com/dialogflow/cx/docs/how/long-running-operation).
// The returned Operation type has the following method-specific fields:
//
//   metadata: KnowledgeOperationMetadata
//
//   response: An Empty
//   message (at https://developers.google.com/protocol-buffers/docs/reference/google.protobuf#empty)
func (c *DocumentsClient) DeleteDocument(ctx context.Context, req *dialogflowpb.DeleteDocumentRequest, opts ...gax.CallOption) (*DeleteDocumentOperation, error) {
	return c.internalClient.DeleteDocument(ctx, req, opts...)
}

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

// UpdateDocument updates the specified document.
//
// This method is a long-running
// operation (at https://cloud.google.com/dialogflow/cx/docs/how/long-running-operation).
// The returned Operation type has the following method-specific fields:
//
//   metadata: KnowledgeOperationMetadata
//
//   response: Document
func (c *DocumentsClient) UpdateDocument(ctx context.Context, req *dialogflowpb.UpdateDocumentRequest, opts ...gax.CallOption) (*UpdateDocumentOperation, error) {
	return c.internalClient.UpdateDocument(ctx, req, opts...)
}

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

// ReloadDocument reloads the specified document from its specified source, content_uri or
// content. The previously loaded content of the document will be deleted.
// Note: Even when the content of the document has not changed, there still
// may be side effects because of internal implementation changes.
//
// This method is a long-running
// operation (at https://cloud.google.com/dialogflow/cx/docs/how/long-running-operation).
// The returned Operation type has the following method-specific fields:
//
//   metadata: KnowledgeOperationMetadata
//
//   response: Document
//
// Note: The projects.agent.knowledgeBases.documents resource is deprecated;
// only use projects.knowledgeBases.documents.
func (c *DocumentsClient) ReloadDocument(ctx context.Context, req *dialogflowpb.ReloadDocumentRequest, opts ...gax.CallOption) (*ReloadDocumentOperation, error) {
	return c.internalClient.ReloadDocument(ctx, req, opts...)
}

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

// ExportDocument exports a smart messaging candidate document into the specified
// destination.
//
// This method is a long-running
// operation (at https://cloud.google.com/dialogflow/cx/docs/how/long-running-operation).
// The returned Operation type has the following method-specific fields:
//
//   metadata: KnowledgeOperationMetadata
//
//   response: Document
func (c *DocumentsClient) ExportDocument(ctx context.Context, req *dialogflowpb.ExportDocumentRequest, opts ...gax.CallOption) (*ExportDocumentOperation, error) {
	return c.internalClient.ExportDocument(ctx, req, opts...)
}

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

// GetLocation gets information about a location.
func (c *DocumentsClient) GetLocation(ctx context.Context, req *locationpb.GetLocationRequest, opts ...gax.CallOption) (*locationpb.Location, error) {
	return c.internalClient.GetLocation(ctx, req, opts...)
}

// ListLocations lists information about the supported locations for this service.
func (c *DocumentsClient) ListLocations(ctx context.Context, req *locationpb.ListLocationsRequest, opts ...gax.CallOption) *LocationIterator {
	return c.internalClient.ListLocations(ctx, req, opts...)
}

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

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

	// flag to opt out of default deadlines via GOOGLE_API_GO_EXPERIMENTAL_DISABLE_DEFAULT_DEADLINE
	disableDeadlines bool

	// Points back to the CallOptions field of the containing DocumentsClient
	CallOptions **DocumentsCallOptions

	// The gRPC API client.
	documentsClient dialogflowpb.DocumentsClient

	// 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

	locationsClient locationpb.LocationsClient

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

// NewDocumentsClient creates a new documents client based on gRPC.
// The returned client must be Closed when it is done being used to clean up its underlying connections.
//
// Service for managing knowledge Documents.
func NewDocumentsClient(ctx context.Context, opts ...option.ClientOption) (*DocumentsClient, error) {
	clientOpts := defaultDocumentsGRPCClientOptions()
	if newDocumentsClientHook != nil {
		hookOpts, err := newDocumentsClientHook(ctx, clientHookParams{})
		if err != nil {
			return nil, err
		}
		clientOpts = append(clientOpts, hookOpts...)
	}

	disableDeadlines, err := checkDisableDeadlines()
	if err != nil {
		return nil, err
	}

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

	c := &documentsGRPCClient{
		connPool:         connPool,
		disableDeadlines: disableDeadlines,
		documentsClient:  dialogflowpb.NewDocumentsClient(connPool),
		CallOptions:      &client.CallOptions,
		operationsClient: longrunningpb.NewOperationsClient(connPool),
		locationsClient:  locationpb.NewLocationsClient(connPool),
	}
	c.setGoogleClientInfo()

	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.
func (c *documentsGRPCClient) 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 *documentsGRPCClient) setGoogleClientInfo(keyval ...string) {
	kv := append([]string{"gl-go", versionGo()}, keyval...)
	kv = append(kv, "gapic", getVersionClient(), "gax", gax.Version, "grpc", grpc.Version)
	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 *documentsGRPCClient) Close() error {
	return c.connPool.Close()
}

func (c *documentsGRPCClient) ListDocuments(ctx context.Context, req *dialogflowpb.ListDocumentsRequest, opts ...gax.CallOption) *DocumentIterator {
	md := metadata.Pairs("x-goog-request-params", fmt.Sprintf("%s=%v", "parent", url.QueryEscape(req.GetParent())))

	ctx = insertMetadata(ctx, c.xGoogMetadata, md)
	opts = append((*c.CallOptions).ListDocuments[0:len((*c.CallOptions).ListDocuments):len((*c.CallOptions).ListDocuments)], opts...)
	it := &DocumentIterator{}
	req = proto.Clone(req).(*dialogflowpb.ListDocumentsRequest)
	it.InternalFetch = func(pageSize int, pageToken string) ([]*dialogflowpb.Document, string, error) {
		resp := &dialogflowpb.ListDocumentsResponse{}
		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 = c.documentsClient.ListDocuments(ctx, req, settings.GRPC...)
			return err
		}, opts...)
		if err != nil {
			return nil, "", err
		}

		it.Response = resp
		return resp.GetDocuments(), 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
}

func (c *documentsGRPCClient) GetDocument(ctx context.Context, req *dialogflowpb.GetDocumentRequest, opts ...gax.CallOption) (*dialogflowpb.Document, error) {
	if _, ok := ctx.Deadline(); !ok && !c.disableDeadlines {
		cctx, cancel := context.WithTimeout(ctx, 60000*time.Millisecond)
		defer cancel()
		ctx = cctx
	}
	md := metadata.Pairs("x-goog-request-params", fmt.Sprintf("%s=%v", "name", url.QueryEscape(req.GetName())))

	ctx = insertMetadata(ctx, c.xGoogMetadata, md)
	opts = append((*c.CallOptions).GetDocument[0:len((*c.CallOptions).GetDocument):len((*c.CallOptions).GetDocument)], opts...)
	var resp *dialogflowpb.Document
	err := gax.Invoke(ctx, func(ctx context.Context, settings gax.CallSettings) error {
		var err error
		resp, err = c.documentsClient.GetDocument(ctx, req, settings.GRPC...)
		return err
	}, opts...)
	if err != nil {
		return nil, err
	}
	return resp, nil
}

func (c *documentsGRPCClient) CreateDocument(ctx context.Context, req *dialogflowpb.CreateDocumentRequest, opts ...gax.CallOption) (*CreateDocumentOperation, error) {
	if _, ok := ctx.Deadline(); !ok && !c.disableDeadlines {
		cctx, cancel := context.WithTimeout(ctx, 60000*time.Millisecond)
		defer cancel()
		ctx = cctx
	}
	md := metadata.Pairs("x-goog-request-params", fmt.Sprintf("%s=%v", "parent", url.QueryEscape(req.GetParent())))

	ctx = insertMetadata(ctx, c.xGoogMetadata, md)
	opts = append((*c.CallOptions).CreateDocument[0:len((*c.CallOptions).CreateDocument):len((*c.CallOptions).CreateDocument)], opts...)
	var resp *longrunningpb.Operation
	err := gax.Invoke(ctx, func(ctx context.Context, settings gax.CallSettings) error {
		var err error
		resp, err = c.documentsClient.CreateDocument(ctx, req, settings.GRPC...)
		return err
	}, opts...)
	if err != nil {
		return nil, err
	}
	return &CreateDocumentOperation{
		lro: longrunning.InternalNewOperation(*c.LROClient, resp),
	}, nil
}

func (c *documentsGRPCClient) ImportDocuments(ctx context.Context, req *dialogflowpb.ImportDocumentsRequest, opts ...gax.CallOption) (*ImportDocumentsOperation, error) {
	if _, ok := ctx.Deadline(); !ok && !c.disableDeadlines {
		cctx, cancel := context.WithTimeout(ctx, 60000*time.Millisecond)
		defer cancel()
		ctx = cctx
	}
	md := metadata.Pairs("x-goog-request-params", fmt.Sprintf("%s=%v", "parent", url.QueryEscape(req.GetParent())))

	ctx = insertMetadata(ctx, c.xGoogMetadata, md)
	opts = append((*c.CallOptions).ImportDocuments[0:len((*c.CallOptions).ImportDocuments):len((*c.CallOptions).ImportDocuments)], opts...)
	var resp *longrunningpb.Operation
	err := gax.Invoke(ctx, func(ctx context.Context, settings gax.CallSettings) error {
		var err error
		resp, err = c.documentsClient.ImportDocuments(ctx, req, settings.GRPC...)
		return err
	}, opts...)
	if err != nil {
		return nil, err
	}
	return &ImportDocumentsOperation{
		lro: longrunning.InternalNewOperation(*c.LROClient, resp),
	}, nil
}

func (c *documentsGRPCClient) DeleteDocument(ctx context.Context, req *dialogflowpb.DeleteDocumentRequest, opts ...gax.CallOption) (*DeleteDocumentOperation, error) {
	if _, ok := ctx.Deadline(); !ok && !c.disableDeadlines {
		cctx, cancel := context.WithTimeout(ctx, 60000*time.Millisecond)
		defer cancel()
		ctx = cctx
	}
	md := metadata.Pairs("x-goog-request-params", fmt.Sprintf("%s=%v", "name", url.QueryEscape(req.GetName())))

	ctx = insertMetadata(ctx, c.xGoogMetadata, md)
	opts = append((*c.CallOptions).DeleteDocument[0:len((*c.CallOptions).DeleteDocument):len((*c.CallOptions).DeleteDocument)], opts...)
	var resp *longrunningpb.Operation
	err := gax.Invoke(ctx, func(ctx context.Context, settings gax.CallSettings) error {
		var err error
		resp, err = c.documentsClient.DeleteDocument(ctx, req, settings.GRPC...)
		return err
	}, opts...)
	if err != nil {
		return nil, err
	}
	return &DeleteDocumentOperation{
		lro: longrunning.InternalNewOperation(*c.LROClient, resp),
	}, nil
}

func (c *documentsGRPCClient) UpdateDocument(ctx context.Context, req *dialogflowpb.UpdateDocumentRequest, opts ...gax.CallOption) (*UpdateDocumentOperation, error) {
	if _, ok := ctx.Deadline(); !ok && !c.disableDeadlines {
		cctx, cancel := context.WithTimeout(ctx, 60000*time.Millisecond)
		defer cancel()
		ctx = cctx
	}
	md := metadata.Pairs("x-goog-request-params", fmt.Sprintf("%s=%v", "document.name", url.QueryEscape(req.GetDocument().GetName())))

	ctx = insertMetadata(ctx, c.xGoogMetadata, md)
	opts = append((*c.CallOptions).UpdateDocument[0:len((*c.CallOptions).UpdateDocument):len((*c.CallOptions).UpdateDocument)], opts...)
	var resp *longrunningpb.Operation
	err := gax.Invoke(ctx, func(ctx context.Context, settings gax.CallSettings) error {
		var err error
		resp, err = c.documentsClient.UpdateDocument(ctx, req, settings.GRPC...)
		return err
	}, opts...)
	if err != nil {
		return nil, err
	}
	return &UpdateDocumentOperation{
		lro: longrunning.InternalNewOperation(*c.LROClient, resp),
	}, nil
}

func (c *documentsGRPCClient) ReloadDocument(ctx context.Context, req *dialogflowpb.ReloadDocumentRequest, opts ...gax.CallOption) (*ReloadDocumentOperation, error) {
	if _, ok := ctx.Deadline(); !ok && !c.disableDeadlines {
		cctx, cancel := context.WithTimeout(ctx, 60000*time.Millisecond)
		defer cancel()
		ctx = cctx
	}
	md := metadata.Pairs("x-goog-request-params", fmt.Sprintf("%s=%v", "name", url.QueryEscape(req.GetName())))

	ctx = insertMetadata(ctx, c.xGoogMetadata, md)
	opts = append((*c.CallOptions).ReloadDocument[0:len((*c.CallOptions).ReloadDocument):len((*c.CallOptions).ReloadDocument)], opts...)
	var resp *longrunningpb.Operation
	err := gax.Invoke(ctx, func(ctx context.Context, settings gax.CallSettings) error {
		var err error
		resp, err = c.documentsClient.ReloadDocument(ctx, req, settings.GRPC...)
		return err
	}, opts...)
	if err != nil {
		return nil, err
	}
	return &ReloadDocumentOperation{
		lro: longrunning.InternalNewOperation(*c.LROClient, resp),
	}, nil
}

func (c *documentsGRPCClient) ExportDocument(ctx context.Context, req *dialogflowpb.ExportDocumentRequest, opts ...gax.CallOption) (*ExportDocumentOperation, error) {
	if _, ok := ctx.Deadline(); !ok && !c.disableDeadlines {
		cctx, cancel := context.WithTimeout(ctx, 60000*time.Millisecond)
		defer cancel()
		ctx = cctx
	}
	md := metadata.Pairs("x-goog-request-params", fmt.Sprintf("%s=%v", "name", url.QueryEscape(req.GetName())))

	ctx = insertMetadata(ctx, c.xGoogMetadata, md)
	opts = append((*c.CallOptions).ExportDocument[0:len((*c.CallOptions).ExportDocument):len((*c.CallOptions).ExportDocument)], opts...)
	var resp *longrunningpb.Operation
	err := gax.Invoke(ctx, func(ctx context.Context, settings gax.CallSettings) error {
		var err error
		resp, err = c.documentsClient.ExportDocument(ctx, req, settings.GRPC...)
		return err
	}, opts...)
	if err != nil {
		return nil, err
	}
	return &ExportDocumentOperation{
		lro: longrunning.InternalNewOperation(*c.LROClient, resp),
	}, nil
}

func (c *documentsGRPCClient) GetLocation(ctx context.Context, req *locationpb.GetLocationRequest, opts ...gax.CallOption) (*locationpb.Location, error) {
	md := metadata.Pairs("x-goog-request-params", fmt.Sprintf("%s=%v", "name", url.QueryEscape(req.GetName())))

	ctx = insertMetadata(ctx, c.xGoogMetadata, md)
	opts = append((*c.CallOptions).GetLocation[0:len((*c.CallOptions).GetLocation):len((*c.CallOptions).GetLocation)], opts...)
	var resp *locationpb.Location
	err := gax.Invoke(ctx, func(ctx context.Context, settings gax.CallSettings) error {
		var err error
		resp, err = c.locationsClient.GetLocation(ctx, req, settings.GRPC...)
		return err
	}, opts...)
	if err != nil {
		return nil, err
	}
	return resp, nil
}

func (c *documentsGRPCClient) ListLocations(ctx context.Context, req *locationpb.ListLocationsRequest, opts ...gax.CallOption) *LocationIterator {
	md := metadata.Pairs("x-goog-request-params", fmt.Sprintf("%s=%v", "name", url.QueryEscape(req.GetName())))

	ctx = insertMetadata(ctx, c.xGoogMetadata, md)
	opts = append((*c.CallOptions).ListLocations[0:len((*c.CallOptions).ListLocations):len((*c.CallOptions).ListLocations)], opts...)
	it := &LocationIterator{}
	req = proto.Clone(req).(*locationpb.ListLocationsRequest)
	it.InternalFetch = func(pageSize int, pageToken string) ([]*locationpb.Location, string, error) {
		resp := &locationpb.ListLocationsResponse{}
		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 = c.locationsClient.ListLocations(ctx, req, settings.GRPC...)
			return err
		}, opts...)
		if err != nil {
			return nil, "", err
		}

		it.Response = resp
		return resp.GetLocations(), 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
}

func (c *documentsGRPCClient) CancelOperation(ctx context.Context, req *longrunningpb.CancelOperationRequest, opts ...gax.CallOption) error {
	md := metadata.Pairs("x-goog-request-params", fmt.Sprintf("%s=%v", "name", url.QueryEscape(req.GetName())))

	ctx = insertMetadata(ctx, c.xGoogMetadata, md)
	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 = c.operationsClient.CancelOperation(ctx, req, settings.GRPC...)
		return err
	}, opts...)
	return err
}

func (c *documentsGRPCClient) GetOperation(ctx context.Context, req *longrunningpb.GetOperationRequest, opts ...gax.CallOption) (*longrunningpb.Operation, error) {
	md := metadata.Pairs("x-goog-request-params", fmt.Sprintf("%s=%v", "name", url.QueryEscape(req.GetName())))

	ctx = insertMetadata(ctx, c.xGoogMetadata, md)
	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 = c.operationsClient.GetOperation(ctx, req, settings.GRPC...)
		return err
	}, opts...)
	if err != nil {
		return nil, err
	}
	return resp, nil
}

func (c *documentsGRPCClient) ListOperations(ctx context.Context, req *longrunningpb.ListOperationsRequest, opts ...gax.CallOption) *OperationIterator {
	md := metadata.Pairs("x-goog-request-params", fmt.Sprintf("%s=%v", "name", url.QueryEscape(req.GetName())))

	ctx = insertMetadata(ctx, c.xGoogMetadata, md)
	opts = append((*c.CallOptions).ListOperations[0:len((*c.CallOptions).ListOperations):len((*c.CallOptions).ListOperations)], opts...)
	it := &OperationIterator{}
	req = proto.Clone(req).(*longrunningpb.ListOperationsRequest)
	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 = c.operationsClient.ListOperations(ctx, req, settings.GRPC...)
			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
}

// CreateDocumentOperation manages a long-running operation from CreateDocument.
type CreateDocumentOperation struct {
	lro *longrunning.Operation
}

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

// Wait blocks until the long-running operation is completed, returning the response and any errors encountered.
//
// See documentation of Poll for error-handling information.
func (op *CreateDocumentOperation) Wait(ctx context.Context, opts ...gax.CallOption) (*dialogflowpb.Document, error) {
	var resp dialogflowpb.Document
	if err := op.lro.WaitWithInterval(ctx, &resp, time.Minute, opts...); err != nil {
		return nil, err
	}
	return &resp, nil
}

// Poll fetches the latest state of the long-running operation.
//
// Poll also fetches the latest metadata, which can be retrieved by Metadata.
//
// If Poll fails, the error is returned and op is unmodified. If Poll succeeds and
// the operation has completed with failure, the error is returned and op.Done will return true.
// If Poll succeeds and the operation has completed successfully,
// op.Done will return true, and the response of the operation is returned.
// If Poll succeeds and the operation has not completed, the returned response and error are both nil.
func (op *CreateDocumentOperation) Poll(ctx context.Context, opts ...gax.CallOption) (*dialogflowpb.Document, error) {
	var resp dialogflowpb.Document
	if err := op.lro.Poll(ctx, &resp, opts...); err != nil {
		return nil, err
	}
	if !op.Done() {
		return nil, nil
	}
	return &resp, nil
}

// Metadata returns metadata associated with the long-running operation.
// Metadata itself does not contact the server, but Poll does.
// To get the latest metadata, call this method after a successful call to Poll.
// If the metadata is not available, the returned metadata and error are both nil.
func (op *CreateDocumentOperation) Metadata() (*dialogflowpb.KnowledgeOperationMetadata, error) {
	var meta dialogflowpb.KnowledgeOperationMetadata
	if err := op.lro.Metadata(&meta); err == longrunning.ErrNoMetadata {
		return nil, nil
	} else if err != nil {
		return nil, err
	}
	return &meta, nil
}

// Done reports whether the long-running operation has completed.
func (op *CreateDocumentOperation) Done() bool {
	return op.lro.Done()
}

// Name returns the name of the long-running operation.
// The name is assigned by the server and is unique within the service from which the operation is created.
func (op *CreateDocumentOperation) Name() string {
	return op.lro.Name()
}

// DeleteDocumentOperation manages a long-running operation from DeleteDocument.
type DeleteDocumentOperation struct {
	lro *longrunning.Operation
}

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

// Wait blocks until the long-running operation is completed, returning the response and any errors encountered.
//
// See documentation of Poll for error-handling information.
func (op *DeleteDocumentOperation) Wait(ctx context.Context, opts ...gax.CallOption) error {
	return op.lro.WaitWithInterval(ctx, nil, time.Minute, opts...)
}

// Poll fetches the latest state of the long-running operation.
//
// Poll also fetches the latest metadata, which can be retrieved by Metadata.
//
// If Poll fails, the error is returned and op is unmodified. If Poll succeeds and
// the operation has completed with failure, the error is returned and op.Done will return true.
// If Poll succeeds and the operation has completed successfully,
// op.Done will return true, and the response of the operation is returned.
// If Poll succeeds and the operation has not completed, the returned response and error are both nil.
func (op *DeleteDocumentOperation) Poll(ctx context.Context, opts ...gax.CallOption) error {
	return op.lro.Poll(ctx, nil, opts...)
}

// Metadata returns metadata associated with the long-running operation.
// Metadata itself does not contact the server, but Poll does.
// To get the latest metadata, call this method after a successful call to Poll.
// If the metadata is not available, the returned metadata and error are both nil.
func (op *DeleteDocumentOperation) Metadata() (*dialogflowpb.KnowledgeOperationMetadata, error) {
	var meta dialogflowpb.KnowledgeOperationMetadata
	if err := op.lro.Metadata(&meta); err == longrunning.ErrNoMetadata {
		return nil, nil
	} else if err != nil {
		return nil, err
	}
	return &meta, nil
}

// Done reports whether the long-running operation has completed.
func (op *DeleteDocumentOperation) Done() bool {
	return op.lro.Done()
}

// Name returns the name of the long-running operation.
// The name is assigned by the server and is unique within the service from which the operation is created.
func (op *DeleteDocumentOperation) Name() string {
	return op.lro.Name()
}

// ExportDocumentOperation manages a long-running operation from ExportDocument.
type ExportDocumentOperation struct {
	lro *longrunning.Operation
}

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

// Wait blocks until the long-running operation is completed, returning the response and any errors encountered.
//
// See documentation of Poll for error-handling information.
func (op *ExportDocumentOperation) Wait(ctx context.Context, opts ...gax.CallOption) (*dialogflowpb.Document, error) {
	var resp dialogflowpb.Document
	if err := op.lro.WaitWithInterval(ctx, &resp, time.Minute, opts...); err != nil {
		return nil, err
	}
	return &resp, nil
}

// Poll fetches the latest state of the long-running operation.
//
// Poll also fetches the latest metadata, which can be retrieved by Metadata.
//
// If Poll fails, the error is returned and op is unmodified. If Poll succeeds and
// the operation has completed with failure, the error is returned and op.Done will return true.
// If Poll succeeds and the operation has completed successfully,
// op.Done will return true, and the response of the operation is returned.
// If Poll succeeds and the operation has not completed, the returned response and error are both nil.
func (op *ExportDocumentOperation) Poll(ctx context.Context, opts ...gax.CallOption) (*dialogflowpb.Document, error) {
	var resp dialogflowpb.Document
	if err := op.lro.Poll(ctx, &resp, opts...); err != nil {
		return nil, err
	}
	if !op.Done() {
		return nil, nil
	}
	return &resp, nil
}

// Metadata returns metadata associated with the long-running operation.
// Metadata itself does not contact the server, but Poll does.
// To get the latest metadata, call this method after a successful call to Poll.
// If the metadata is not available, the returned metadata and error are both nil.
func (op *ExportDocumentOperation) Metadata() (*dialogflowpb.KnowledgeOperationMetadata, error) {
	var meta dialogflowpb.KnowledgeOperationMetadata
	if err := op.lro.Metadata(&meta); err == longrunning.ErrNoMetadata {
		return nil, nil
	} else if err != nil {
		return nil, err
	}
	return &meta, nil
}

// Done reports whether the long-running operation has completed.
func (op *ExportDocumentOperation) Done() bool {
	return op.lro.Done()
}

// Name returns the name of the long-running operation.
// The name is assigned by the server and is unique within the service from which the operation is created.
func (op *ExportDocumentOperation) Name() string {
	return op.lro.Name()
}

// ImportDocumentsOperation manages a long-running operation from ImportDocuments.
type ImportDocumentsOperation struct {
	lro *longrunning.Operation
}

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

// Wait blocks until the long-running operation is completed, returning the response and any errors encountered.
//
// See documentation of Poll for error-handling information.
func (op *ImportDocumentsOperation) Wait(ctx context.Context, opts ...gax.CallOption) (*dialogflowpb.ImportDocumentsResponse, error) {
	var resp dialogflowpb.ImportDocumentsResponse
	if err := op.lro.WaitWithInterval(ctx, &resp, time.Minute, opts...); err != nil {
		return nil, err
	}
	return &resp, nil
}

// Poll fetches the latest state of the long-running operation.
//
// Poll also fetches the latest metadata, which can be retrieved by Metadata.
//
// If Poll fails, the error is returned and op is unmodified. If Poll succeeds and
// the operation has completed with failure, the error is returned and op.Done will return true.
// If Poll succeeds and the operation has completed successfully,
// op.Done will return true, and the response of the operation is returned.
// If Poll succeeds and the operation has not completed, the returned response and error are both nil.
func (op *ImportDocumentsOperation) Poll(ctx context.Context, opts ...gax.CallOption) (*dialogflowpb.ImportDocumentsResponse, error) {
	var resp dialogflowpb.ImportDocumentsResponse
	if err := op.lro.Poll(ctx, &resp, opts...); err != nil {
		return nil, err
	}
	if !op.Done() {
		return nil, nil
	}
	return &resp, nil
}

// Metadata returns metadata associated with the long-running operation.
// Metadata itself does not contact the server, but Poll does.
// To get the latest metadata, call this method after a successful call to Poll.
// If the metadata is not available, the returned metadata and error are both nil.
func (op *ImportDocumentsOperation) Metadata() (*dialogflowpb.KnowledgeOperationMetadata, error) {
	var meta dialogflowpb.KnowledgeOperationMetadata
	if err := op.lro.Metadata(&meta); err == longrunning.ErrNoMetadata {
		return nil, nil
	} else if err != nil {
		return nil, err
	}
	return &meta, nil
}

// Done reports whether the long-running operation has completed.
func (op *ImportDocumentsOperation) Done() bool {
	return op.lro.Done()
}

// Name returns the name of the long-running operation.
// The name is assigned by the server and is unique within the service from which the operation is created.
func (op *ImportDocumentsOperation) Name() string {
	return op.lro.Name()
}

// ReloadDocumentOperation manages a long-running operation from ReloadDocument.
type ReloadDocumentOperation struct {
	lro *longrunning.Operation
}

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

// Wait blocks until the long-running operation is completed, returning the response and any errors encountered.
//
// See documentation of Poll for error-handling information.
func (op *ReloadDocumentOperation) Wait(ctx context.Context, opts ...gax.CallOption) (*dialogflowpb.Document, error) {
	var resp dialogflowpb.Document
	if err := op.lro.WaitWithInterval(ctx, &resp, time.Minute, opts...); err != nil {
		return nil, err
	}
	return &resp, nil
}

// Poll fetches the latest state of the long-running operation.
//
// Poll also fetches the latest metadata, which can be retrieved by Metadata.
//
// If Poll fails, the error is returned and op is unmodified. If Poll succeeds and
// the operation has completed with failure, the error is returned and op.Done will return true.
// If Poll succeeds and the operation has completed successfully,
// op.Done will return true, and the response of the operation is returned.
// If Poll succeeds and the operation has not completed, the returned response and error are both nil.
func (op *ReloadDocumentOperation) Poll(ctx context.Context, opts ...gax.CallOption) (*dialogflowpb.Document, error) {
	var resp dialogflowpb.Document
	if err := op.lro.Poll(ctx, &resp, opts...); err != nil {
		return nil, err
	}
	if !op.Done() {
		return nil, nil
	}
	return &resp, nil
}

// Metadata returns metadata associated with the long-running operation.
// Metadata itself does not contact the server, but Poll does.
// To get the latest metadata, call this method after a successful call to Poll.
// If the metadata is not available, the returned metadata and error are both nil.
func (op *ReloadDocumentOperation) Metadata() (*dialogflowpb.KnowledgeOperationMetadata, error) {
	var meta dialogflowpb.KnowledgeOperationMetadata
	if err := op.lro.Metadata(&meta); err == longrunning.ErrNoMetadata {
		return nil, nil
	} else if err != nil {
		return nil, err
	}
	return &meta, nil
}

// Done reports whether the long-running operation has completed.
func (op *ReloadDocumentOperation) Done() bool {
	return op.lro.Done()
}

// Name returns the name of the long-running operation.
// The name is assigned by the server and is unique within the service from which the operation is created.
func (op *ReloadDocumentOperation) Name() string {
	return op.lro.Name()
}

// UpdateDocumentOperation manages a long-running operation from UpdateDocument.
type UpdateDocumentOperation struct {
	lro *longrunning.Operation
}

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

// Wait blocks until the long-running operation is completed, returning the response and any errors encountered.
//
// See documentation of Poll for error-handling information.
func (op *UpdateDocumentOperation) Wait(ctx context.Context, opts ...gax.CallOption) (*dialogflowpb.Document, error) {
	var resp dialogflowpb.Document
	if err := op.lro.WaitWithInterval(ctx, &resp, time.Minute, opts...); err != nil {
		return nil, err
	}
	return &resp, nil
}

// Poll fetches the latest state of the long-running operation.
//
// Poll also fetches the latest metadata, which can be retrieved by Metadata.
//
// If Poll fails, the error is returned and op is unmodified. If Poll succeeds and
// the operation has completed with failure, the error is returned and op.Done will return true.
// If Poll succeeds and the operation has completed successfully,
// op.Done will return true, and the response of the operation is returned.
// If Poll succeeds and the operation has not completed, the returned response and error are both nil.
func (op *UpdateDocumentOperation) Poll(ctx context.Context, opts ...gax.CallOption) (*dialogflowpb.Document, error) {
	var resp dialogflowpb.Document
	if err := op.lro.Poll(ctx, &resp, opts...); err != nil {
		return nil, err
	}
	if !op.Done() {
		return nil, nil
	}
	return &resp, nil
}

// Metadata returns metadata associated with the long-running operation.
// Metadata itself does not contact the server, but Poll does.
// To get the latest metadata, call this method after a successful call to Poll.
// If the metadata is not available, the returned metadata and error are both nil.
func (op *UpdateDocumentOperation) Metadata() (*dialogflowpb.KnowledgeOperationMetadata, error) {
	var meta dialogflowpb.KnowledgeOperationMetadata
	if err := op.lro.Metadata(&meta); err == longrunning.ErrNoMetadata {
		return nil, nil
	} else if err != nil {
		return nil, err
	}
	return &meta, nil
}

// Done reports whether the long-running operation has completed.
func (op *UpdateDocumentOperation) Done() bool {
	return op.lro.Done()
}

// Name returns the name of the long-running operation.
// The name is assigned by the server and is unique within the service from which the operation is created.
func (op *UpdateDocumentOperation) Name() string {
	return op.lro.Name()
}

// DocumentIterator manages a stream of *dialogflowpb.Document.
type DocumentIterator struct {
	items    []*dialogflowpb.Document
	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 []*dialogflowpb.Document, nextPageToken string, err error)
}

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

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

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