499 lines
20 KiB
Go
499 lines
20 KiB
Go
// Copyright 2018 Google LLC
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//
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// Licensed under the Apache License, Version 2.0 (the "License");
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// you may not use this file except in compliance with the License.
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// You may obtain a copy of the License at
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//
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// https://www.apache.org/licenses/LICENSE-2.0
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//
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// Unless required by applicable law or agreed to in writing, software
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// distributed under the License is distributed on an "AS IS" BASIS,
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// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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// See the License for the specific language governing permissions and
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// limitations under the License.
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// AUTO-GENERATED CODE. DO NOT EDIT.
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package spanner
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import (
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"math"
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"time"
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"cloud.google.com/go/internal/version"
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gax "github.com/googleapis/gax-go"
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"golang.org/x/net/context"
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"google.golang.org/api/iterator"
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"google.golang.org/api/option"
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"google.golang.org/api/transport"
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spannerpb "google.golang.org/genproto/googleapis/spanner/v1"
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"google.golang.org/grpc"
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"google.golang.org/grpc/codes"
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"google.golang.org/grpc/metadata"
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)
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// CallOptions contains the retry settings for each method of Client.
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type CallOptions struct {
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CreateSession []gax.CallOption
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GetSession []gax.CallOption
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ListSessions []gax.CallOption
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DeleteSession []gax.CallOption
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ExecuteSql []gax.CallOption
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ExecuteStreamingSql []gax.CallOption
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Read []gax.CallOption
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StreamingRead []gax.CallOption
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BeginTransaction []gax.CallOption
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Commit []gax.CallOption
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Rollback []gax.CallOption
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PartitionQuery []gax.CallOption
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PartitionRead []gax.CallOption
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}
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func defaultClientOptions() []option.ClientOption {
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return []option.ClientOption{
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option.WithEndpoint("spanner.googleapis.com:443"),
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option.WithScopes(DefaultAuthScopes()...),
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}
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}
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func defaultCallOptions() *CallOptions {
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retry := map[[2]string][]gax.CallOption{
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{"default", "idempotent"}: {
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gax.WithRetry(func() gax.Retryer {
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return gax.OnCodes([]codes.Code{
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codes.DeadlineExceeded,
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codes.Unavailable,
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}, gax.Backoff{
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Initial: 1000 * time.Millisecond,
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Max: 32000 * time.Millisecond,
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Multiplier: 1.3,
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})
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}),
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},
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{"long_running", "long_running"}: {
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gax.WithRetry(func() gax.Retryer {
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return gax.OnCodes([]codes.Code{
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codes.Unavailable,
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}, gax.Backoff{
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Initial: 1000 * time.Millisecond,
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Max: 32000 * time.Millisecond,
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Multiplier: 1.3,
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})
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}),
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},
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}
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return &CallOptions{
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CreateSession: retry[[2]string{"default", "idempotent"}],
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GetSession: retry[[2]string{"default", "idempotent"}],
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ListSessions: retry[[2]string{"default", "idempotent"}],
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DeleteSession: retry[[2]string{"default", "idempotent"}],
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ExecuteSql: retry[[2]string{"default", "idempotent"}],
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ExecuteStreamingSql: retry[[2]string{"default", "non_idempotent"}],
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Read: retry[[2]string{"default", "idempotent"}],
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StreamingRead: retry[[2]string{"default", "non_idempotent"}],
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BeginTransaction: retry[[2]string{"default", "idempotent"}],
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Commit: retry[[2]string{"long_running", "long_running"}],
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Rollback: retry[[2]string{"default", "idempotent"}],
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PartitionQuery: retry[[2]string{"default", "idempotent"}],
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PartitionRead: retry[[2]string{"default", "idempotent"}],
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}
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}
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// Client is a client for interacting with Cloud Spanner API.
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type Client struct {
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// The connection to the service.
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conn *grpc.ClientConn
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// The gRPC API client.
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client spannerpb.SpannerClient
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// The call options for this service.
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CallOptions *CallOptions
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// The x-goog-* metadata to be sent with each request.
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xGoogMetadata metadata.MD
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}
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// NewClient creates a new spanner client.
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//
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// Cloud Spanner API
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//
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// The Cloud Spanner API can be used to manage sessions and execute
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// transactions on data stored in Cloud Spanner databases.
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func NewClient(ctx context.Context, opts ...option.ClientOption) (*Client, error) {
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conn, err := transport.DialGRPC(ctx, append(defaultClientOptions(), opts...)...)
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if err != nil {
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return nil, err
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}
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c := &Client{
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conn: conn,
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CallOptions: defaultCallOptions(),
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client: spannerpb.NewSpannerClient(conn),
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}
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c.SetGoogleClientInfo()
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return c, nil
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}
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// Connection returns the client's connection to the API service.
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func (c *Client) Connection() *grpc.ClientConn {
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return c.conn
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}
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// Close closes the connection to the API service. The user should invoke this when
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// the client is no longer required.
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func (c *Client) Close() error {
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return c.conn.Close()
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}
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// SetGoogleClientInfo sets the name and version of the application in
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// the `x-goog-api-client` header passed on each request. Intended for
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// use by Google-written clients.
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func (c *Client) SetGoogleClientInfo(keyval ...string) {
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kv := append([]string{"gl-go", version.Go()}, keyval...)
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kv = append(kv, "gapic", version.Repo, "gax", gax.Version, "grpc", grpc.Version)
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c.xGoogMetadata = metadata.Pairs("x-goog-api-client", gax.XGoogHeader(kv...))
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}
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// CreateSession creates a new session. A session can be used to perform
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// transactions that read and/or modify data in a Cloud Spanner database.
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// Sessions are meant to be reused for many consecutive
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// transactions.
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//
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// Sessions can only execute one transaction at a time. To execute
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// multiple concurrent read-write/write-only transactions, create
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// multiple sessions. Note that standalone reads and queries use a
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// transaction internally, and count toward the one transaction
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// limit.
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//
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// Cloud Spanner limits the number of sessions that can exist at any given
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// time; thus, it is a good idea to delete idle and/or unneeded sessions.
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// Aside from explicit deletes, Cloud Spanner can delete sessions for which no
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// operations are sent for more than an hour. If a session is deleted,
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// requests to it return NOT_FOUND.
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//
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// Idle sessions can be kept alive by sending a trivial SQL query
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// periodically, e.g., "SELECT 1".
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func (c *Client) CreateSession(ctx context.Context, req *spannerpb.CreateSessionRequest, opts ...gax.CallOption) (*spannerpb.Session, error) {
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ctx = insertMetadata(ctx, c.xGoogMetadata)
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opts = append(c.CallOptions.CreateSession[0:len(c.CallOptions.CreateSession):len(c.CallOptions.CreateSession)], opts...)
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var resp *spannerpb.Session
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err := gax.Invoke(ctx, func(ctx context.Context, settings gax.CallSettings) error {
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var err error
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resp, err = c.client.CreateSession(ctx, req, settings.GRPC...)
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return err
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}, opts...)
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if err != nil {
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return nil, err
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}
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return resp, nil
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}
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// GetSession gets a session. Returns NOT_FOUND if the session does not exist.
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// This is mainly useful for determining whether a session is still
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// alive.
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func (c *Client) GetSession(ctx context.Context, req *spannerpb.GetSessionRequest, opts ...gax.CallOption) (*spannerpb.Session, error) {
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ctx = insertMetadata(ctx, c.xGoogMetadata)
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opts = append(c.CallOptions.GetSession[0:len(c.CallOptions.GetSession):len(c.CallOptions.GetSession)], opts...)
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var resp *spannerpb.Session
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err := gax.Invoke(ctx, func(ctx context.Context, settings gax.CallSettings) error {
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var err error
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resp, err = c.client.GetSession(ctx, req, settings.GRPC...)
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return err
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}, opts...)
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if err != nil {
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return nil, err
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}
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return resp, nil
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}
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// ListSessions lists all sessions in a given database.
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func (c *Client) ListSessions(ctx context.Context, req *spannerpb.ListSessionsRequest, opts ...gax.CallOption) *SessionIterator {
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ctx = insertMetadata(ctx, c.xGoogMetadata)
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opts = append(c.CallOptions.ListSessions[0:len(c.CallOptions.ListSessions):len(c.CallOptions.ListSessions)], opts...)
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it := &SessionIterator{}
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it.InternalFetch = func(pageSize int, pageToken string) ([]*spannerpb.Session, string, error) {
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var resp *spannerpb.ListSessionsResponse
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req.PageToken = pageToken
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if pageSize > math.MaxInt32 {
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req.PageSize = math.MaxInt32
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} else {
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req.PageSize = int32(pageSize)
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}
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err := gax.Invoke(ctx, func(ctx context.Context, settings gax.CallSettings) error {
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var err error
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resp, err = c.client.ListSessions(ctx, req, settings.GRPC...)
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return err
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}, opts...)
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if err != nil {
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return nil, "", err
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}
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return resp.Sessions, resp.NextPageToken, nil
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}
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fetch := func(pageSize int, pageToken string) (string, error) {
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items, nextPageToken, err := it.InternalFetch(pageSize, pageToken)
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if err != nil {
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return "", err
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}
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it.items = append(it.items, items...)
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return nextPageToken, nil
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}
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it.pageInfo, it.nextFunc = iterator.NewPageInfo(fetch, it.bufLen, it.takeBuf)
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return it
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}
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// DeleteSession ends a session, releasing server resources associated with it.
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func (c *Client) DeleteSession(ctx context.Context, req *spannerpb.DeleteSessionRequest, opts ...gax.CallOption) error {
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ctx = insertMetadata(ctx, c.xGoogMetadata)
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opts = append(c.CallOptions.DeleteSession[0:len(c.CallOptions.DeleteSession):len(c.CallOptions.DeleteSession)], opts...)
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err := gax.Invoke(ctx, func(ctx context.Context, settings gax.CallSettings) error {
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var err error
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_, err = c.client.DeleteSession(ctx, req, settings.GRPC...)
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return err
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}, opts...)
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return err
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}
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// ExecuteSql executes an SQL query, returning all rows in a single reply. This
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// method cannot be used to return a result set larger than 10 MiB;
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// if the query yields more data than that, the query fails with
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// a FAILED_PRECONDITION error.
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//
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// Queries inside read-write transactions might return ABORTED. If
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// this occurs, the application should restart the transaction from
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// the beginning. See [Transaction][google.spanner.v1.Transaction] for more details.
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//
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// Larger result sets can be fetched in streaming fashion by calling
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// [ExecuteStreamingSql][google.spanner.v1.Spanner.ExecuteStreamingSql] instead.
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func (c *Client) ExecuteSql(ctx context.Context, req *spannerpb.ExecuteSqlRequest, opts ...gax.CallOption) (*spannerpb.ResultSet, error) {
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ctx = insertMetadata(ctx, c.xGoogMetadata)
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opts = append(c.CallOptions.ExecuteSql[0:len(c.CallOptions.ExecuteSql):len(c.CallOptions.ExecuteSql)], opts...)
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var resp *spannerpb.ResultSet
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err := gax.Invoke(ctx, func(ctx context.Context, settings gax.CallSettings) error {
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var err error
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resp, err = c.client.ExecuteSql(ctx, req, settings.GRPC...)
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return err
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}, opts...)
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if err != nil {
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return nil, err
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}
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return resp, nil
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}
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// ExecuteStreamingSql like [ExecuteSql][google.spanner.v1.Spanner.ExecuteSql], except returns the result
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// set as a stream. Unlike [ExecuteSql][google.spanner.v1.Spanner.ExecuteSql], there
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// is no limit on the size of the returned result set. However, no
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// individual row in the result set can exceed 100 MiB, and no
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// column value can exceed 10 MiB.
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func (c *Client) ExecuteStreamingSql(ctx context.Context, req *spannerpb.ExecuteSqlRequest, opts ...gax.CallOption) (spannerpb.Spanner_ExecuteStreamingSqlClient, error) {
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ctx = insertMetadata(ctx, c.xGoogMetadata)
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opts = append(c.CallOptions.ExecuteStreamingSql[0:len(c.CallOptions.ExecuteStreamingSql):len(c.CallOptions.ExecuteStreamingSql)], opts...)
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var resp spannerpb.Spanner_ExecuteStreamingSqlClient
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err := gax.Invoke(ctx, func(ctx context.Context, settings gax.CallSettings) error {
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var err error
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resp, err = c.client.ExecuteStreamingSql(ctx, req, settings.GRPC...)
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return err
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}, opts...)
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if err != nil {
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return nil, err
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}
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return resp, nil
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}
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// Read reads rows from the database using key lookups and scans, as a
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// simple key/value style alternative to
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// [ExecuteSql][google.spanner.v1.Spanner.ExecuteSql]. This method cannot be used to
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// return a result set larger than 10 MiB; if the read matches more
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// data than that, the read fails with a FAILED_PRECONDITION
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// error.
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//
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// Reads inside read-write transactions might return ABORTED. If
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// this occurs, the application should restart the transaction from
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// the beginning. See [Transaction][google.spanner.v1.Transaction] for more details.
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//
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// Larger result sets can be yielded in streaming fashion by calling
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// [StreamingRead][google.spanner.v1.Spanner.StreamingRead] instead.
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func (c *Client) Read(ctx context.Context, req *spannerpb.ReadRequest, opts ...gax.CallOption) (*spannerpb.ResultSet, error) {
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ctx = insertMetadata(ctx, c.xGoogMetadata)
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opts = append(c.CallOptions.Read[0:len(c.CallOptions.Read):len(c.CallOptions.Read)], opts...)
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var resp *spannerpb.ResultSet
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err := gax.Invoke(ctx, func(ctx context.Context, settings gax.CallSettings) error {
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var err error
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resp, err = c.client.Read(ctx, req, settings.GRPC...)
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return err
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}, opts...)
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if err != nil {
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return nil, err
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}
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return resp, nil
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}
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// StreamingRead like [Read][google.spanner.v1.Spanner.Read], except returns the result set as a
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// stream. Unlike [Read][google.spanner.v1.Spanner.Read], there is no limit on the
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// size of the returned result set. However, no individual row in
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// the result set can exceed 100 MiB, and no column value can exceed
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// 10 MiB.
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func (c *Client) StreamingRead(ctx context.Context, req *spannerpb.ReadRequest, opts ...gax.CallOption) (spannerpb.Spanner_StreamingReadClient, error) {
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ctx = insertMetadata(ctx, c.xGoogMetadata)
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opts = append(c.CallOptions.StreamingRead[0:len(c.CallOptions.StreamingRead):len(c.CallOptions.StreamingRead)], opts...)
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var resp spannerpb.Spanner_StreamingReadClient
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err := gax.Invoke(ctx, func(ctx context.Context, settings gax.CallSettings) error {
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var err error
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resp, err = c.client.StreamingRead(ctx, req, settings.GRPC...)
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return err
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}, opts...)
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if err != nil {
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return nil, err
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}
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return resp, nil
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}
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// BeginTransaction begins a new transaction. This step can often be skipped:
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// [Read][google.spanner.v1.Spanner.Read], [ExecuteSql][google.spanner.v1.Spanner.ExecuteSql] and
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// [Commit][google.spanner.v1.Spanner.Commit] can begin a new transaction as a
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// side-effect.
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func (c *Client) BeginTransaction(ctx context.Context, req *spannerpb.BeginTransactionRequest, opts ...gax.CallOption) (*spannerpb.Transaction, error) {
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ctx = insertMetadata(ctx, c.xGoogMetadata)
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opts = append(c.CallOptions.BeginTransaction[0:len(c.CallOptions.BeginTransaction):len(c.CallOptions.BeginTransaction)], opts...)
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var resp *spannerpb.Transaction
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err := gax.Invoke(ctx, func(ctx context.Context, settings gax.CallSettings) error {
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var err error
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resp, err = c.client.BeginTransaction(ctx, req, settings.GRPC...)
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return err
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}, opts...)
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if err != nil {
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return nil, err
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}
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return resp, nil
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}
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// Commit commits a transaction. The request includes the mutations to be
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// applied to rows in the database.
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//
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// Commit might return an ABORTED error. This can occur at any time;
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// commonly, the cause is conflicts with concurrent
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// transactions. However, it can also happen for a variety of other
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// reasons. If Commit returns ABORTED, the caller should re-attempt
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// the transaction from the beginning, re-using the same session.
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func (c *Client) Commit(ctx context.Context, req *spannerpb.CommitRequest, opts ...gax.CallOption) (*spannerpb.CommitResponse, error) {
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ctx = insertMetadata(ctx, c.xGoogMetadata)
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opts = append(c.CallOptions.Commit[0:len(c.CallOptions.Commit):len(c.CallOptions.Commit)], opts...)
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var resp *spannerpb.CommitResponse
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err := gax.Invoke(ctx, func(ctx context.Context, settings gax.CallSettings) error {
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var err error
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resp, err = c.client.Commit(ctx, req, settings.GRPC...)
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return err
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}, opts...)
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if err != nil {
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return nil, err
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}
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return resp, nil
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}
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// Rollback rolls back a transaction, releasing any locks it holds. It is a good
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// idea to call this for any transaction that includes one or more
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// [Read][google.spanner.v1.Spanner.Read] or [ExecuteSql][google.spanner.v1.Spanner.ExecuteSql] requests and
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// ultimately decides not to commit.
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//
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// Rollback returns OK if it successfully aborts the transaction, the
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// transaction was already aborted, or the transaction is not
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// found. Rollback never returns ABORTED.
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func (c *Client) Rollback(ctx context.Context, req *spannerpb.RollbackRequest, opts ...gax.CallOption) error {
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ctx = insertMetadata(ctx, c.xGoogMetadata)
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opts = append(c.CallOptions.Rollback[0:len(c.CallOptions.Rollback):len(c.CallOptions.Rollback)], opts...)
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err := gax.Invoke(ctx, func(ctx context.Context, settings gax.CallSettings) error {
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var err error
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_, err = c.client.Rollback(ctx, req, settings.GRPC...)
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return err
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}, opts...)
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return err
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}
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// PartitionQuery creates a set of partition tokens that can be used to execute a query
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// operation in parallel. Each of the returned partition tokens can be used
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// by [ExecuteStreamingSql][google.spanner.v1.Spanner.ExecuteStreamingSql] to specify a subset
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// of the query result to read. The same session and read-only transaction
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// must be used by the PartitionQueryRequest used to create the
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// partition tokens and the ExecuteSqlRequests that use the partition tokens.
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// Partition tokens become invalid when the session used to create them
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// is deleted or begins a new transaction.
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func (c *Client) PartitionQuery(ctx context.Context, req *spannerpb.PartitionQueryRequest, opts ...gax.CallOption) (*spannerpb.PartitionResponse, error) {
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ctx = insertMetadata(ctx, c.xGoogMetadata)
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opts = append(c.CallOptions.PartitionQuery[0:len(c.CallOptions.PartitionQuery):len(c.CallOptions.PartitionQuery)], opts...)
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var resp *spannerpb.PartitionResponse
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err := gax.Invoke(ctx, func(ctx context.Context, settings gax.CallSettings) error {
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var err error
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resp, err = c.client.PartitionQuery(ctx, req, settings.GRPC...)
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return err
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}, opts...)
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if err != nil {
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return nil, err
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}
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return resp, nil
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}
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// PartitionRead creates a set of partition tokens that can be used to execute a read
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// operation in parallel. Each of the returned partition tokens can be used
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// by [StreamingRead][google.spanner.v1.Spanner.StreamingRead] to specify a subset of the read
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// result to read. The same session and read-only transaction must be used by
|
|
// the PartitionReadRequest used to create the partition tokens and the
|
|
// ReadRequests that use the partition tokens.
|
|
// Partition tokens become invalid when the session used to create them
|
|
// is deleted or begins a new transaction.
|
|
func (c *Client) PartitionRead(ctx context.Context, req *spannerpb.PartitionReadRequest, opts ...gax.CallOption) (*spannerpb.PartitionResponse, error) {
|
|
ctx = insertMetadata(ctx, c.xGoogMetadata)
|
|
opts = append(c.CallOptions.PartitionRead[0:len(c.CallOptions.PartitionRead):len(c.CallOptions.PartitionRead)], opts...)
|
|
var resp *spannerpb.PartitionResponse
|
|
err := gax.Invoke(ctx, func(ctx context.Context, settings gax.CallSettings) error {
|
|
var err error
|
|
resp, err = c.client.PartitionRead(ctx, req, settings.GRPC...)
|
|
return err
|
|
}, opts...)
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
return resp, nil
|
|
}
|
|
|
|
// SessionIterator manages a stream of *spannerpb.Session.
|
|
type SessionIterator struct {
|
|
items []*spannerpb.Session
|
|
pageInfo *iterator.PageInfo
|
|
nextFunc func() error
|
|
|
|
// 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 []*spannerpb.Session, nextPageToken string, err error)
|
|
}
|
|
|
|
// PageInfo supports pagination. See the google.golang.org/api/iterator package for details.
|
|
func (it *SessionIterator) 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 *SessionIterator) Next() (*spannerpb.Session, error) {
|
|
var item *spannerpb.Session
|
|
if err := it.nextFunc(); err != nil {
|
|
return item, err
|
|
}
|
|
item = it.items[0]
|
|
it.items = it.items[1:]
|
|
return item, nil
|
|
}
|
|
|
|
func (it *SessionIterator) bufLen() int {
|
|
return len(it.items)
|
|
}
|
|
|
|
func (it *SessionIterator) takeBuf() interface{} {
|
|
b := it.items
|
|
it.items = nil
|
|
return b
|
|
}
|