| // Copyright 2019 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 gapic-generator. DO NOT EDIT. |
| |
| package spanner |
| |
| import ( |
| "context" |
| "fmt" |
| "math" |
| "net/url" |
| "time" |
| |
| "github.com/golang/protobuf/proto" |
| gax "github.com/googleapis/gax-go/v2" |
| "google.golang.org/api/iterator" |
| "google.golang.org/api/option" |
| "google.golang.org/api/transport" |
| spannerpb "google.golang.org/genproto/googleapis/spanner/v1" |
| "google.golang.org/grpc" |
| "google.golang.org/grpc/codes" |
| "google.golang.org/grpc/metadata" |
| ) |
| |
| // CallOptions contains the retry settings for each method of Client. |
| type CallOptions struct { |
| CreateSession []gax.CallOption |
| GetSession []gax.CallOption |
| ListSessions []gax.CallOption |
| DeleteSession []gax.CallOption |
| ExecuteSql []gax.CallOption |
| ExecuteStreamingSql []gax.CallOption |
| ExecuteBatchDml []gax.CallOption |
| Read []gax.CallOption |
| StreamingRead []gax.CallOption |
| BeginTransaction []gax.CallOption |
| Commit []gax.CallOption |
| Rollback []gax.CallOption |
| PartitionQuery []gax.CallOption |
| PartitionRead []gax.CallOption |
| } |
| |
| func defaultClientOptions() []option.ClientOption { |
| return []option.ClientOption{ |
| option.WithEndpoint("spanner.googleapis.com:443"), |
| option.WithScopes(DefaultAuthScopes()...), |
| } |
| } |
| |
| func defaultCallOptions() *CallOptions { |
| retry := map[[2]string][]gax.CallOption{ |
| {"default", "idempotent"}: { |
| gax.WithRetry(func() gax.Retryer { |
| return gax.OnCodes([]codes.Code{ |
| codes.Unavailable, |
| }, gax.Backoff{ |
| Initial: 250 * time.Millisecond, |
| Max: 32000 * time.Millisecond, |
| Multiplier: 1.3, |
| }) |
| }), |
| }, |
| {"long_running", "long_running"}: { |
| gax.WithRetry(func() gax.Retryer { |
| return gax.OnCodes([]codes.Code{ |
| codes.Unavailable, |
| }, gax.Backoff{ |
| Initial: 250 * time.Millisecond, |
| Max: 32000 * time.Millisecond, |
| Multiplier: 1.3, |
| }) |
| }), |
| }, |
| } |
| return &CallOptions{ |
| CreateSession: retry[[2]string{"default", "idempotent"}], |
| GetSession: retry[[2]string{"default", "idempotent"}], |
| ListSessions: retry[[2]string{"default", "idempotent"}], |
| DeleteSession: retry[[2]string{"default", "idempotent"}], |
| ExecuteSql: retry[[2]string{"default", "idempotent"}], |
| ExecuteStreamingSql: retry[[2]string{"streaming", "non_idempotent"}], |
| ExecuteBatchDml: retry[[2]string{"default", "idempotent"}], |
| Read: retry[[2]string{"default", "idempotent"}], |
| StreamingRead: retry[[2]string{"streaming", "non_idempotent"}], |
| BeginTransaction: retry[[2]string{"default", "idempotent"}], |
| Commit: retry[[2]string{"long_running", "long_running"}], |
| Rollback: retry[[2]string{"default", "idempotent"}], |
| PartitionQuery: retry[[2]string{"default", "idempotent"}], |
| PartitionRead: retry[[2]string{"default", "idempotent"}], |
| } |
| } |
| |
| // Client is a client for interacting with Cloud Spanner API. |
| // |
| // Methods, except Close, may be called concurrently. However, fields must not be modified concurrently with method calls. |
| type Client struct { |
| // The connection to the service. |
| conn *grpc.ClientConn |
| |
| // The gRPC API client. |
| client spannerpb.SpannerClient |
| |
| // The call options for this service. |
| CallOptions *CallOptions |
| |
| // The x-goog-* metadata to be sent with each request. |
| xGoogMetadata metadata.MD |
| } |
| |
| // NewClient creates a new spanner client. |
| // |
| // Cloud Spanner API |
| // |
| // The Cloud Spanner API can be used to manage sessions and execute |
| // transactions on data stored in Cloud Spanner databases. |
| func NewClient(ctx context.Context, opts ...option.ClientOption) (*Client, error) { |
| conn, err := transport.DialGRPC(ctx, append(defaultClientOptions(), opts...)...) |
| if err != nil { |
| return nil, err |
| } |
| c := &Client{ |
| conn: conn, |
| CallOptions: defaultCallOptions(), |
| |
| client: spannerpb.NewSpannerClient(conn), |
| } |
| c.SetGoogleClientInfo() |
| return c, nil |
| } |
| |
| // Connection returns the client's connection to the API service. |
| func (c *Client) Connection() *grpc.ClientConn { |
| return c.conn |
| } |
| |
| // Close closes the connection to the API service. The user should invoke this when |
| // the client is no longer required. |
| func (c *Client) Close() error { |
| return c.conn.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 *Client) SetGoogleClientInfo(keyval ...string) { |
| kv := append([]string{"gl-go", versionGo()}, keyval...) |
| kv = append(kv, "gapic", versionClient, "gax", gax.Version, "grpc", grpc.Version) |
| c.xGoogMetadata = metadata.Pairs("x-goog-api-client", gax.XGoogHeader(kv...)) |
| } |
| |
| // CreateSession creates a new session. A session can be used to perform |
| // transactions that read and/or modify data in a Cloud Spanner database. |
| // Sessions are meant to be reused for many consecutive |
| // transactions. |
| // |
| // Sessions can only execute one transaction at a time. To execute |
| // multiple concurrent read-write/write-only transactions, create |
| // multiple sessions. Note that standalone reads and queries use a |
| // transaction internally, and count toward the one transaction |
| // limit. |
| // |
| // Cloud Spanner limits the number of sessions that can exist at any given |
| // time; thus, it is a good idea to delete idle and/or unneeded sessions. |
| // Aside from explicit deletes, Cloud Spanner can delete sessions for which no |
| // operations are sent for more than an hour. If a session is deleted, |
| // requests to it return NOT_FOUND. |
| // |
| // Idle sessions can be kept alive by sending a trivial SQL query |
| // periodically, e.g., "SELECT 1". |
| func (c *Client) CreateSession(ctx context.Context, req *spannerpb.CreateSessionRequest, opts ...gax.CallOption) (*spannerpb.Session, error) { |
| md := metadata.Pairs("x-goog-request-params", fmt.Sprintf("%s=%v", "database", url.QueryEscape(req.GetDatabase()))) |
| ctx = insertMetadata(ctx, c.xGoogMetadata, md) |
| opts = append(c.CallOptions.CreateSession[0:len(c.CallOptions.CreateSession):len(c.CallOptions.CreateSession)], opts...) |
| var resp *spannerpb.Session |
| err := gax.Invoke(ctx, func(ctx context.Context, settings gax.CallSettings) error { |
| var err error |
| resp, err = c.client.CreateSession(ctx, req, settings.GRPC...) |
| return err |
| }, opts...) |
| if err != nil { |
| return nil, err |
| } |
| return resp, nil |
| } |
| |
| // GetSession gets a session. Returns NOT_FOUND if the session does not exist. |
| // This is mainly useful for determining whether a session is still |
| // alive. |
| func (c *Client) GetSession(ctx context.Context, req *spannerpb.GetSessionRequest, opts ...gax.CallOption) (*spannerpb.Session, 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.GetSession[0:len(c.CallOptions.GetSession):len(c.CallOptions.GetSession)], opts...) |
| var resp *spannerpb.Session |
| err := gax.Invoke(ctx, func(ctx context.Context, settings gax.CallSettings) error { |
| var err error |
| resp, err = c.client.GetSession(ctx, req, settings.GRPC...) |
| return err |
| }, opts...) |
| if err != nil { |
| return nil, err |
| } |
| return resp, nil |
| } |
| |
| // ListSessions lists all sessions in a given database. |
| func (c *Client) ListSessions(ctx context.Context, req *spannerpb.ListSessionsRequest, opts ...gax.CallOption) *SessionIterator { |
| md := metadata.Pairs("x-goog-request-params", fmt.Sprintf("%s=%v", "database", url.QueryEscape(req.GetDatabase()))) |
| ctx = insertMetadata(ctx, c.xGoogMetadata, md) |
| opts = append(c.CallOptions.ListSessions[0:len(c.CallOptions.ListSessions):len(c.CallOptions.ListSessions)], opts...) |
| it := &SessionIterator{} |
| req = proto.Clone(req).(*spannerpb.ListSessionsRequest) |
| it.InternalFetch = func(pageSize int, pageToken string) ([]*spannerpb.Session, string, error) { |
| var resp *spannerpb.ListSessionsResponse |
| req.PageToken = pageToken |
| if pageSize > math.MaxInt32 { |
| req.PageSize = math.MaxInt32 |
| } else { |
| req.PageSize = int32(pageSize) |
| } |
| err := gax.Invoke(ctx, func(ctx context.Context, settings gax.CallSettings) error { |
| var err error |
| resp, err = c.client.ListSessions(ctx, req, settings.GRPC...) |
| return err |
| }, opts...) |
| if err != nil { |
| return nil, "", err |
| } |
| return resp.Sessions, resp.NextPageToken, 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.PageSize) |
| it.pageInfo.Token = req.PageToken |
| return it |
| } |
| |
| // DeleteSession ends a session, releasing server resources associated with it. This will |
| // asynchronously trigger cancellation of any operations that are running with |
| // this session. |
| func (c *Client) DeleteSession(ctx context.Context, req *spannerpb.DeleteSessionRequest, 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.DeleteSession[0:len(c.CallOptions.DeleteSession):len(c.CallOptions.DeleteSession)], opts...) |
| err := gax.Invoke(ctx, func(ctx context.Context, settings gax.CallSettings) error { |
| var err error |
| _, err = c.client.DeleteSession(ctx, req, settings.GRPC...) |
| return err |
| }, opts...) |
| return err |
| } |
| |
| // ExecuteSql executes an SQL statement, returning all results in a single reply. This |
| // method cannot be used to return a result set larger than 10 MiB; |
| // if the query yields more data than that, the query fails with |
| // a FAILED_PRECONDITION error. |
| // |
| // Operations inside read-write transactions might return ABORTED. If |
| // this occurs, the application should restart the transaction from |
| // the beginning. See [Transaction][google.spanner.v1.Transaction] for more |
| // details. |
| // |
| // Larger result sets can be fetched in streaming fashion by calling |
| // [ExecuteStreamingSql][google.spanner.v1.Spanner.ExecuteStreamingSql] |
| // instead. |
| func (c *Client) ExecuteSql(ctx context.Context, req *spannerpb.ExecuteSqlRequest, opts ...gax.CallOption) (*spannerpb.ResultSet, error) { |
| md := metadata.Pairs("x-goog-request-params", fmt.Sprintf("%s=%v", "session", url.QueryEscape(req.GetSession()))) |
| ctx = insertMetadata(ctx, c.xGoogMetadata, md) |
| opts = append(c.CallOptions.ExecuteSql[0:len(c.CallOptions.ExecuteSql):len(c.CallOptions.ExecuteSql)], opts...) |
| var resp *spannerpb.ResultSet |
| err := gax.Invoke(ctx, func(ctx context.Context, settings gax.CallSettings) error { |
| var err error |
| resp, err = c.client.ExecuteSql(ctx, req, settings.GRPC...) |
| return err |
| }, opts...) |
| if err != nil { |
| return nil, err |
| } |
| return resp, nil |
| } |
| |
| // ExecuteStreamingSql like [ExecuteSql][google.spanner.v1.Spanner.ExecuteSql], except returns the |
| // result set as a stream. Unlike |
| // [ExecuteSql][google.spanner.v1.Spanner.ExecuteSql], there is no limit on |
| // the size of the returned result set. However, no individual row in the |
| // result set can exceed 100 MiB, and no column value can exceed 10 MiB. |
| func (c *Client) ExecuteStreamingSql(ctx context.Context, req *spannerpb.ExecuteSqlRequest, opts ...gax.CallOption) (spannerpb.Spanner_ExecuteStreamingSqlClient, error) { |
| md := metadata.Pairs("x-goog-request-params", fmt.Sprintf("%s=%v", "session", url.QueryEscape(req.GetSession()))) |
| ctx = insertMetadata(ctx, c.xGoogMetadata, md) |
| opts = append(c.CallOptions.ExecuteStreamingSql[0:len(c.CallOptions.ExecuteStreamingSql):len(c.CallOptions.ExecuteStreamingSql)], opts...) |
| var resp spannerpb.Spanner_ExecuteStreamingSqlClient |
| err := gax.Invoke(ctx, func(ctx context.Context, settings gax.CallSettings) error { |
| var err error |
| resp, err = c.client.ExecuteStreamingSql(ctx, req, settings.GRPC...) |
| return err |
| }, opts...) |
| if err != nil { |
| return nil, err |
| } |
| return resp, nil |
| } |
| |
| // ExecuteBatchDml executes a batch of SQL DML statements. This method allows many statements |
| // to be run with lower latency than submitting them sequentially with |
| // [ExecuteSql][google.spanner.v1.Spanner.ExecuteSql]. |
| // |
| // Statements are executed in order, sequentially. |
| // [ExecuteBatchDmlResponse][Spanner.ExecuteBatchDmlResponse] will contain a |
| // [ResultSet][google.spanner.v1.ResultSet] for each DML statement that has successfully executed. If a |
| // statement fails, its error status will be returned as part of the |
| // [ExecuteBatchDmlResponse][Spanner.ExecuteBatchDmlResponse]. Execution will |
| // stop at the first failed statement; the remaining statements will not run. |
| // |
| // ExecuteBatchDml is expected to return an OK status with a response even if |
| // there was an error while processing one of the DML statements. Clients must |
| // inspect response.status to determine if there were any errors while |
| // processing the request. |
| // |
| // See more details in |
| // [ExecuteBatchDmlRequest][Spanner.ExecuteBatchDmlRequest] and |
| // [ExecuteBatchDmlResponse][Spanner.ExecuteBatchDmlResponse]. |
| func (c *Client) ExecuteBatchDml(ctx context.Context, req *spannerpb.ExecuteBatchDmlRequest, opts ...gax.CallOption) (*spannerpb.ExecuteBatchDmlResponse, error) { |
| md := metadata.Pairs("x-goog-request-params", fmt.Sprintf("%s=%v", "session", url.QueryEscape(req.GetSession()))) |
| ctx = insertMetadata(ctx, c.xGoogMetadata, md) |
| opts = append(c.CallOptions.ExecuteBatchDml[0:len(c.CallOptions.ExecuteBatchDml):len(c.CallOptions.ExecuteBatchDml)], opts...) |
| var resp *spannerpb.ExecuteBatchDmlResponse |
| err := gax.Invoke(ctx, func(ctx context.Context, settings gax.CallSettings) error { |
| var err error |
| resp, err = c.client.ExecuteBatchDml(ctx, req, settings.GRPC...) |
| return err |
| }, opts...) |
| if err != nil { |
| return nil, err |
| } |
| return resp, nil |
| } |
| |
| // Read reads rows from the database using key lookups and scans, as a |
| // simple key/value style alternative to |
| // [ExecuteSql][google.spanner.v1.Spanner.ExecuteSql]. This method cannot be |
| // used to return a result set larger than 10 MiB; if the read matches more |
| // data than that, the read fails with a FAILED_PRECONDITION |
| // error. |
| // |
| // Reads inside read-write transactions might return ABORTED. If |
| // this occurs, the application should restart the transaction from |
| // the beginning. See [Transaction][google.spanner.v1.Transaction] for more |
| // details. |
| // |
| // Larger result sets can be yielded in streaming fashion by calling |
| // [StreamingRead][google.spanner.v1.Spanner.StreamingRead] instead. |
| func (c *Client) Read(ctx context.Context, req *spannerpb.ReadRequest, opts ...gax.CallOption) (*spannerpb.ResultSet, error) { |
| md := metadata.Pairs("x-goog-request-params", fmt.Sprintf("%s=%v", "session", url.QueryEscape(req.GetSession()))) |
| ctx = insertMetadata(ctx, c.xGoogMetadata, md) |
| opts = append(c.CallOptions.Read[0:len(c.CallOptions.Read):len(c.CallOptions.Read)], opts...) |
| var resp *spannerpb.ResultSet |
| err := gax.Invoke(ctx, func(ctx context.Context, settings gax.CallSettings) error { |
| var err error |
| resp, err = c.client.Read(ctx, req, settings.GRPC...) |
| return err |
| }, opts...) |
| if err != nil { |
| return nil, err |
| } |
| return resp, nil |
| } |
| |
| // StreamingRead like [Read][google.spanner.v1.Spanner.Read], except returns the result set |
| // as a stream. Unlike [Read][google.spanner.v1.Spanner.Read], there is no |
| // limit on the size of the returned result set. However, no individual row in |
| // the result set can exceed 100 MiB, and no column value can exceed |
| // 10 MiB. |
| func (c *Client) StreamingRead(ctx context.Context, req *spannerpb.ReadRequest, opts ...gax.CallOption) (spannerpb.Spanner_StreamingReadClient, error) { |
| md := metadata.Pairs("x-goog-request-params", fmt.Sprintf("%s=%v", "session", url.QueryEscape(req.GetSession()))) |
| ctx = insertMetadata(ctx, c.xGoogMetadata, md) |
| opts = append(c.CallOptions.StreamingRead[0:len(c.CallOptions.StreamingRead):len(c.CallOptions.StreamingRead)], opts...) |
| var resp spannerpb.Spanner_StreamingReadClient |
| err := gax.Invoke(ctx, func(ctx context.Context, settings gax.CallSettings) error { |
| var err error |
| resp, err = c.client.StreamingRead(ctx, req, settings.GRPC...) |
| return err |
| }, opts...) |
| if err != nil { |
| return nil, err |
| } |
| return resp, nil |
| } |
| |
| // BeginTransaction begins a new transaction. This step can often be skipped: |
| // [Read][google.spanner.v1.Spanner.Read], |
| // [ExecuteSql][google.spanner.v1.Spanner.ExecuteSql] and |
| // [Commit][google.spanner.v1.Spanner.Commit] can begin a new transaction as a |
| // side-effect. |
| func (c *Client) BeginTransaction(ctx context.Context, req *spannerpb.BeginTransactionRequest, opts ...gax.CallOption) (*spannerpb.Transaction, error) { |
| md := metadata.Pairs("x-goog-request-params", fmt.Sprintf("%s=%v", "session", url.QueryEscape(req.GetSession()))) |
| ctx = insertMetadata(ctx, c.xGoogMetadata, md) |
| opts = append(c.CallOptions.BeginTransaction[0:len(c.CallOptions.BeginTransaction):len(c.CallOptions.BeginTransaction)], opts...) |
| var resp *spannerpb.Transaction |
| err := gax.Invoke(ctx, func(ctx context.Context, settings gax.CallSettings) error { |
| var err error |
| resp, err = c.client.BeginTransaction(ctx, req, settings.GRPC...) |
| return err |
| }, opts...) |
| if err != nil { |
| return nil, err |
| } |
| return resp, nil |
| } |
| |
| // Commit commits a transaction. The request includes the mutations to be |
| // applied to rows in the database. |
| // |
| // Commit might return an ABORTED error. This can occur at any time; |
| // commonly, the cause is conflicts with concurrent |
| // transactions. However, it can also happen for a variety of other |
| // reasons. If Commit returns ABORTED, the caller should re-attempt |
| // the transaction from the beginning, re-using the same session. |
| func (c *Client) Commit(ctx context.Context, req *spannerpb.CommitRequest, opts ...gax.CallOption) (*spannerpb.CommitResponse, error) { |
| md := metadata.Pairs("x-goog-request-params", fmt.Sprintf("%s=%v", "session", url.QueryEscape(req.GetSession()))) |
| ctx = insertMetadata(ctx, c.xGoogMetadata, md) |
| opts = append(c.CallOptions.Commit[0:len(c.CallOptions.Commit):len(c.CallOptions.Commit)], opts...) |
| var resp *spannerpb.CommitResponse |
| err := gax.Invoke(ctx, func(ctx context.Context, settings gax.CallSettings) error { |
| var err error |
| resp, err = c.client.Commit(ctx, req, settings.GRPC...) |
| return err |
| }, opts...) |
| if err != nil { |
| return nil, err |
| } |
| return resp, nil |
| } |
| |
| // Rollback rolls back a transaction, releasing any locks it holds. It is a good |
| // idea to call this for any transaction that includes one or more |
| // [Read][google.spanner.v1.Spanner.Read] or |
| // [ExecuteSql][google.spanner.v1.Spanner.ExecuteSql] requests and ultimately |
| // decides not to commit. |
| // |
| // Rollback returns OK if it successfully aborts the transaction, the |
| // transaction was already aborted, or the transaction is not |
| // found. Rollback never returns ABORTED. |
| func (c *Client) Rollback(ctx context.Context, req *spannerpb.RollbackRequest, opts ...gax.CallOption) error { |
| md := metadata.Pairs("x-goog-request-params", fmt.Sprintf("%s=%v", "session", url.QueryEscape(req.GetSession()))) |
| ctx = insertMetadata(ctx, c.xGoogMetadata, md) |
| opts = append(c.CallOptions.Rollback[0:len(c.CallOptions.Rollback):len(c.CallOptions.Rollback)], opts...) |
| err := gax.Invoke(ctx, func(ctx context.Context, settings gax.CallSettings) error { |
| var err error |
| _, err = c.client.Rollback(ctx, req, settings.GRPC...) |
| return err |
| }, opts...) |
| return err |
| } |
| |
| // PartitionQuery creates a set of partition tokens that can be used to execute a query |
| // operation in parallel. Each of the returned partition tokens can be used |
| // by [ExecuteStreamingSql][google.spanner.v1.Spanner.ExecuteStreamingSql] to |
| // specify a subset of the query result to read. The same session and |
| // read-only transaction must be used by the PartitionQueryRequest used to |
| // create the partition tokens and the ExecuteSqlRequests that use the |
| // partition tokens. |
| // |
| // Partition tokens become invalid when the session used to create them |
| // is deleted, is idle for too long, begins a new transaction, or becomes too |
| // old. When any of these happen, it is not possible to resume the query, and |
| // the whole operation must be restarted from the beginning. |
| func (c *Client) PartitionQuery(ctx context.Context, req *spannerpb.PartitionQueryRequest, opts ...gax.CallOption) (*spannerpb.PartitionResponse, error) { |
| md := metadata.Pairs("x-goog-request-params", fmt.Sprintf("%s=%v", "session", url.QueryEscape(req.GetSession()))) |
| ctx = insertMetadata(ctx, c.xGoogMetadata, md) |
| opts = append(c.CallOptions.PartitionQuery[0:len(c.CallOptions.PartitionQuery):len(c.CallOptions.PartitionQuery)], opts...) |
| var resp *spannerpb.PartitionResponse |
| err := gax.Invoke(ctx, func(ctx context.Context, settings gax.CallSettings) error { |
| var err error |
| resp, err = c.client.PartitionQuery(ctx, req, settings.GRPC...) |
| return err |
| }, opts...) |
| if err != nil { |
| return nil, err |
| } |
| return resp, nil |
| } |
| |
| // PartitionRead creates a set of partition tokens that can be used to execute a read |
| // operation in parallel. Each of the returned partition tokens can be used |
| // by [StreamingRead][google.spanner.v1.Spanner.StreamingRead] to specify a |
| // subset of the read 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. There |
| // are no ordering guarantees on rows returned among the returned partition |
| // tokens, or even within each individual StreamingRead call issued with a |
| // partition_token. |
| // |
| // Partition tokens become invalid when the session used to create them |
| // is deleted, is idle for too long, begins a new transaction, or becomes too |
| // old. When any of these happen, it is not possible to resume the read, and |
| // the whole operation must be restarted from the beginning. |
| func (c *Client) PartitionRead(ctx context.Context, req *spannerpb.PartitionReadRequest, opts ...gax.CallOption) (*spannerpb.PartitionResponse, error) { |
| md := metadata.Pairs("x-goog-request-params", fmt.Sprintf("%s=%v", "session", url.QueryEscape(req.GetSession()))) |
| ctx = insertMetadata(ctx, c.xGoogMetadata, md) |
| 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 |
| } |