SpannerClient

SpannerClient

Cloud Spanner API

The Cloud Spanner API can be used to manage sessions and execute transactions on data stored in Cloud Spanner databases.

Constructor

new SpannerClient(optionsopt)

Construct an instance of SpannerClient.

Parameters:
Name Type Attributes Description
options object <optional>

The configuration object. See the subsequent parameters for more details.

Properties
Name Type Attributes Description
credentials object <optional>

Credentials object.

Properties
Name Type Attributes Description
client_email string <optional>
private_key string <optional>
email string <optional>

Account email address. Required when using a .pem or .p12 keyFilename.

keyFilename string <optional>

Full path to the a .json, .pem, or .p12 key downloaded from the Google Developers Console. If you provide a path to a JSON file, the projectId option below is not necessary. NOTE: .pem and .p12 require you to specify options.email as well.

port number <optional>

The port on which to connect to the remote host.

projectId string <optional>

The project ID from the Google Developer's Console, e.g. 'grape-spaceship-123'. We will also check the environment variable GCLOUD_PROJECT for your project ID. If your app is running in an environment which supports Application Default Credentials, your project ID will be detected automatically.

apiEndpoint string <optional>

The domain name of the API remote host.

Members

(static) apiEndpoint

The DNS address for this API service - same as servicePath(), exists for compatibility reasons.

(static) port

The port for this API service.

(static) scopes

The scopes needed to make gRPC calls for every method defined in this service.

(static) servicePath

The DNS address for this API service.

Methods

batchCreateSessions(request, optionsopt) → {Promise}

Creates multiple new sessions.

This API can be used to initialize a session cache on the clients. See https://goo.gl/TgSFN2 for best practices on session cache management.

Parameters:
Name Type Attributes Description
request Object

The request object that will be sent.

Properties
Name Type Description
database string

Required. The database in which the new sessions are created.

sessionTemplate google.spanner.v1.Session

Parameters to be applied to each created session.

sessionCount number

Required. The number of sessions to be created in this batch call. The API may return fewer than the requested number of sessions. If a specific number of sessions are desired, the client can make additional calls to BatchCreateSessions (adjusting session_count as necessary).

options object <optional>

Call options. See CallOptions for more details.

beginTransaction(request, optionsopt) → {Promise}

Begins a new transaction. This step can often be skipped: Read, ExecuteSql and Commit can begin a new transaction as a side-effect.

Parameters:
Name Type Attributes Description
request Object

The request object that will be sent.

Properties
Name Type Description
session string

Required. The session in which the transaction runs.

options google.spanner.v1.TransactionOptions

Required. Options for the new transaction.

options object <optional>

Call options. See CallOptions for more details.

close()

Terminate the GRPC channel and close the client.

The client will no longer be usable and all future behavior is undefined.

commit(request, optionsopt) → {Promise}

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.

Parameters:
Name Type Attributes Description
request Object

The request object that will be sent.

Properties
Name Type Description
session string

Required. The session in which the transaction to be committed is running.

transactionId Buffer

Commit a previously-started transaction.

singleUseTransaction google.spanner.v1.TransactionOptions

Execute mutations in a temporary transaction. Note that unlike commit of a previously-started transaction, commit with a temporary transaction is non-idempotent. That is, if the CommitRequest is sent to Cloud Spanner more than once (for instance, due to retries in the application, or in the transport library), it is possible that the mutations are executed more than once. If this is undesirable, use BeginTransaction and Commit instead.

mutations Array.<number>

The mutations to be executed when this transaction commits. All mutations are applied atomically, in the order they appear in this list.

options object <optional>

Call options. See CallOptions for more details.

createSession(request, optionsopt) → {Promise}

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.

Active sessions use additional server resources, so it is a good idea to delete idle and unneeded sessions. Aside from explicit deletes, Cloud Spanner may 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".

Parameters:
Name Type Attributes Description
request Object

The request object that will be sent.

Properties
Name Type Description
database string

Required. The database in which the new session is created.

session google.spanner.v1.Session

The session to create.

options object <optional>

Call options. See CallOptions for more details.

databasePath(project, instance, database) → {string}

Return a fully-qualified database resource name string.

Parameters:
Name Type Description
project string
instance string
database string

deleteSession(request, optionsopt) → {Promise}

Ends a session, releasing server resources associated with it. This will asynchronously trigger cancellation of any operations that are running with this session.

Parameters:
Name Type Attributes Description
request Object

The request object that will be sent.

Properties
Name Type Description
name string

Required. The name of the session to delete.

options object <optional>

Call options. See CallOptions for more details.

executeBatchDml(request, optionsopt) → {Promise}

Executes a batch of SQL DML statements. This method allows many statements to be run with lower latency than submitting them sequentially with ExecuteSql.

Statements are executed in sequential order. A request can succeed even if a statement fails. The ExecuteBatchDmlResponse.status field in the response provides information about the statement that failed. Clients must inspect this field to determine whether an error occurred.

Execution stops after the first failed statement; the remaining statements are not executed.

Parameters:
Name Type Attributes Description
request Object

The request object that will be sent.

Properties
Name Type Description
session string

Required. The session in which the DML statements should be performed.

transaction google.spanner.v1.TransactionSelector

Required. The transaction to use. Must be a read-write transaction.

To protect against replays, single-use transactions are not supported. The caller must either supply an existing transaction ID or begin a new transaction.

statements Array.<number>

Required. The list of statements to execute in this batch. Statements are executed serially, such that the effects of statement i are visible to statement i+1. Each statement must be a DML statement. Execution stops at the first failed statement; the remaining statements are not executed.

Callers must provide at least one statement.

seqno number

Required. A per-transaction sequence number used to identify this request. This field makes each request idempotent such that if the request is received multiple times, at most one will succeed.

The sequence number must be monotonically increasing within the transaction. If a request arrives for the first time with an out-of-order sequence number, the transaction may be aborted. Replays of previously handled requests will yield the same response as the first execution.

options object <optional>

Call options. See CallOptions for more details.

executeSql(request, optionsopt) → {Promise}

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 for more details.

Larger result sets can be fetched in streaming fashion by calling ExecuteStreamingSql instead.

Parameters:
Name Type Attributes Description
request Object

The request object that will be sent.

Properties
Name Type Description
session string

Required. The session in which the SQL query should be performed.

transaction google.spanner.v1.TransactionSelector

The transaction to use.

For queries, if none is provided, the default is a temporary read-only transaction with strong concurrency.

Standard DML statements require a read-write transaction. To protect against replays, single-use transactions are not supported. The caller must either supply an existing transaction ID or begin a new transaction.

Partitioned DML requires an existing Partitioned DML transaction ID.

sql string

Required. The SQL string.

params google.protobuf.Struct

Parameter names and values that bind to placeholders in the SQL string.

A parameter placeholder consists of the @ character followed by the parameter name (for example, @firstName). Parameter names can contain letters, numbers, and underscores.

Parameters can appear anywhere that a literal value is expected. The same parameter name can be used more than once, for example:

"WHERE id > @msg_id AND id < @msg_id + 100"

It is an error to execute a SQL statement with unbound parameters.

paramTypes Array.<number>

It is not always possible for Cloud Spanner to infer the right SQL type from a JSON value. For example, values of type BYTES and values of type STRING both appear in params as JSON strings.

In these cases, param_types can be used to specify the exact SQL type for some or all of the SQL statement parameters. See the definition of Type for more information about SQL types.

resumeToken Buffer

If this request is resuming a previously interrupted SQL statement execution, resume_token should be copied from the last PartialResultSet yielded before the interruption. Doing this enables the new SQL statement execution to resume where the last one left off. The rest of the request parameters must exactly match the request that yielded this token.

queryMode google.spanner.v1.ExecuteSqlRequest.QueryMode

Used to control the amount of debugging information returned in ResultSetStats. If partition_token is set, query_mode can only be set to QueryMode.NORMAL.

partitionToken Buffer

If present, results will be restricted to the specified partition previously created using PartitionQuery(). There must be an exact match for the values of fields common to this message and the PartitionQueryRequest message used to create this partition_token.

seqno number

A per-transaction sequence number used to identify this request. This field makes each request idempotent such that if the request is received multiple times, at most one will succeed.

The sequence number must be monotonically increasing within the transaction. If a request arrives for the first time with an out-of-order sequence number, the transaction may be aborted. Replays of previously handled requests will yield the same response as the first execution.

Required for DML statements. Ignored for queries.

queryOptions google.spanner.v1.ExecuteSqlRequest.QueryOptions

Query optimizer configuration to use for the given query.

options object <optional>

Call options. See CallOptions for more details.

executeStreamingSql(request, optionsopt) → {Stream}

Like ExecuteSql, except returns the result set as a stream. Unlike 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.

Parameters:
Name Type Attributes Description
request Object

The request object that will be sent.

Properties
Name Type Description
session string

Required. The session in which the SQL query should be performed.

transaction google.spanner.v1.TransactionSelector

The transaction to use.

For queries, if none is provided, the default is a temporary read-only transaction with strong concurrency.

Standard DML statements require a read-write transaction. To protect against replays, single-use transactions are not supported. The caller must either supply an existing transaction ID or begin a new transaction.

Partitioned DML requires an existing Partitioned DML transaction ID.

sql string

Required. The SQL string.

params google.protobuf.Struct

Parameter names and values that bind to placeholders in the SQL string.

A parameter placeholder consists of the @ character followed by the parameter name (for example, @firstName). Parameter names can contain letters, numbers, and underscores.

Parameters can appear anywhere that a literal value is expected. The same parameter name can be used more than once, for example:

"WHERE id > @msg_id AND id < @msg_id + 100"

It is an error to execute a SQL statement with unbound parameters.

paramTypes Array.<number>

It is not always possible for Cloud Spanner to infer the right SQL type from a JSON value. For example, values of type BYTES and values of type STRING both appear in params as JSON strings.

In these cases, param_types can be used to specify the exact SQL type for some or all of the SQL statement parameters. See the definition of Type for more information about SQL types.

resumeToken Buffer

If this request is resuming a previously interrupted SQL statement execution, resume_token should be copied from the last PartialResultSet yielded before the interruption. Doing this enables the new SQL statement execution to resume where the last one left off. The rest of the request parameters must exactly match the request that yielded this token.

queryMode google.spanner.v1.ExecuteSqlRequest.QueryMode

Used to control the amount of debugging information returned in ResultSetStats. If partition_token is set, query_mode can only be set to QueryMode.NORMAL.

partitionToken Buffer

If present, results will be restricted to the specified partition previously created using PartitionQuery(). There must be an exact match for the values of fields common to this message and the PartitionQueryRequest message used to create this partition_token.

seqno number

A per-transaction sequence number used to identify this request. This field makes each request idempotent such that if the request is received multiple times, at most one will succeed.

The sequence number must be monotonically increasing within the transaction. If a request arrives for the first time with an out-of-order sequence number, the transaction may be aborted. Replays of previously handled requests will yield the same response as the first execution.

Required for DML statements. Ignored for queries.

queryOptions google.spanner.v1.ExecuteSqlRequest.QueryOptions

Query optimizer configuration to use for the given query.

options object <optional>

Call options. See CallOptions for more details.

getProjectId(callback)

Return the project ID used by this class.

Parameters:
Name Type Description
callback function

the callback to be called with the current project Id.

getSession(request, optionsopt) → {Promise}

Gets a session. Returns NOT_FOUND if the session does not exist. This is mainly useful for determining whether a session is still alive.

Parameters:
Name Type Attributes Description
request Object

The request object that will be sent.

Properties
Name Type Description
name string

Required. The name of the session to retrieve.

options object <optional>

Call options. See CallOptions for more details.

initialize() → {Promise}

Initialize the client. Performs asynchronous operations (such as authentication) and prepares the client. This function will be called automatically when any class method is called for the first time, but if you need to initialize it before calling an actual method, feel free to call initialize() directly.

You can await on this method if you want to make sure the client is initialized.

listSessions(request, optionsopt) → {Promise}

Lists all sessions in a given database.

Parameters:
Name Type Attributes Description
request Object

The request object that will be sent.

Properties
Name Type Description
database string

Required. The database in which to list sessions.

pageSize number

Number of sessions to be returned in the response. If 0 or less, defaults to the server's maximum allowed page size.

pageToken string

If non-empty, page_token should contain a next_page_token from a previous ListSessionsResponse.

filter string

An expression for filtering the results of the request. Filter rules are case insensitive. The fields eligible for filtering are:

* `labels.key` where key is the name of a label

Some examples of using filters are:

* `labels.env:*` --> The session has the label "env".
* `labels.env:dev` --> The session has the label "env" and the value of
                     the label contains the string "dev".
options object <optional>

Call options. See CallOptions for more details.

listSessionsAsync(request, optionsopt) → {Object}

Equivalent to listSessions, but returns an iterable object.

for-await-of syntax is used with the iterable to recursively get response element on-demand.

Parameters:
Name Type Attributes Description
request Object

The request object that will be sent.

Properties
Name Type Description
database string

Required. The database in which to list sessions.

pageSize number

Number of sessions to be returned in the response. If 0 or less, defaults to the server's maximum allowed page size.

pageToken string

If non-empty, page_token should contain a next_page_token from a previous ListSessionsResponse.

filter string

An expression for filtering the results of the request. Filter rules are case insensitive. The fields eligible for filtering are:

* `labels.key` where key is the name of a label

Some examples of using filters are:

* `labels.env:*` --> The session has the label "env".
* `labels.env:dev` --> The session has the label "env" and the value of
                     the label contains the string "dev".
options object <optional>

Call options. See CallOptions for more details.

listSessionsStream(request, optionsopt) → {Stream}

Equivalent to listSessions, but returns a NodeJS Stream object.

This fetches the paged responses for listSessions continuously and invokes the callback registered for 'data' event for each element in the responses.

The returned object has 'end' method when no more elements are required.

autoPaginate option will be ignored.

Parameters:
Name Type Attributes Description
request Object

The request object that will be sent.

Properties
Name Type Description
database string

Required. The database in which to list sessions.

pageSize number

Number of sessions to be returned in the response. If 0 or less, defaults to the server's maximum allowed page size.

pageToken string

If non-empty, page_token should contain a next_page_token from a previous ListSessionsResponse.

filter string

An expression for filtering the results of the request. Filter rules are case insensitive. The fields eligible for filtering are:

* `labels.key` where key is the name of a label

Some examples of using filters are:

* `labels.env:*` --> The session has the label "env".
* `labels.env:dev` --> The session has the label "env" and the value of
                     the label contains the string "dev".
options object <optional>

Call options. See CallOptions for more details.

See:

matchDatabaseFromDatabaseName(databaseName) → {string}

Parse the database from Database resource.

Parameters:
Name Type Description
databaseName string

A fully-qualified path representing Database resource.

matchDatabaseFromSessionName(sessionName) → {string}

Parse the database from Session resource.

Parameters:
Name Type Description
sessionName string

A fully-qualified path representing Session resource.

matchInstanceFromDatabaseName(databaseName) → {string}

Parse the instance from Database resource.

Parameters:
Name Type Description
databaseName string

A fully-qualified path representing Database resource.

matchInstanceFromSessionName(sessionName) → {string}

Parse the instance from Session resource.

Parameters:
Name Type Description
sessionName string

A fully-qualified path representing Session resource.

matchProjectFromDatabaseName(databaseName) → {string}

Parse the project from Database resource.

Parameters:
Name Type Description
databaseName string

A fully-qualified path representing Database resource.

matchProjectFromSessionName(sessionName) → {string}

Parse the project from Session resource.

Parameters:
Name Type Description
sessionName string

A fully-qualified path representing Session resource.

matchSessionFromSessionName(sessionName) → {string}

Parse the session from Session resource.

Parameters:
Name Type Description
sessionName string

A fully-qualified path representing Session resource.

partitionQuery(request, optionsopt) → {Promise}

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 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.

Parameters:
Name Type Attributes Description
request Object

The request object that will be sent.

Properties
Name Type Description
session string

Required. The session used to create the partitions.

transaction google.spanner.v1.TransactionSelector

Read only snapshot transactions are supported, read/write and single use transactions are not.

sql string

Required. The query request to generate partitions for. The request will fail if the query is not root partitionable. The query plan of a root partitionable query has a single distributed union operator. A distributed union operator conceptually divides one or more tables into multiple splits, remotely evaluates a subquery independently on each split, and then unions all results.

This must not contain DML commands, such as INSERT, UPDATE, or DELETE. Use ExecuteStreamingSql with a PartitionedDml transaction for large, partition-friendly DML operations.

params google.protobuf.Struct

Parameter names and values that bind to placeholders in the SQL string.

A parameter placeholder consists of the @ character followed by the parameter name (for example, @firstName). Parameter names can contain letters, numbers, and underscores.

Parameters can appear anywhere that a literal value is expected. The same parameter name can be used more than once, for example:

"WHERE id > @msg_id AND id < @msg_id + 100"

It is an error to execute a SQL statement with unbound parameters.

paramTypes Array.<number>

It is not always possible for Cloud Spanner to infer the right SQL type from a JSON value. For example, values of type BYTES and values of type STRING both appear in params as JSON strings.

In these cases, param_types can be used to specify the exact SQL type for some or all of the SQL query parameters. See the definition of Type for more information about SQL types.

partitionOptions google.spanner.v1.PartitionOptions

Additional options that affect how many partitions are created.

options object <optional>

Call options. See CallOptions for more details.

partitionRead(request, optionsopt) → {Promise}

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 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.

Parameters:
Name Type Attributes Description
request Object

The request object that will be sent.

Properties
Name Type Description
session string

Required. The session used to create the partitions.

transaction google.spanner.v1.TransactionSelector

Read only snapshot transactions are supported, read/write and single use transactions are not.

table string

Required. The name of the table in the database to be read.

index string

If non-empty, the name of an index on table. This index is used instead of the table primary key when interpreting key_set and sorting result rows. See key_set for further information.

columns Array.<string>

The columns of table to be returned for each row matching this request.

keySet google.spanner.v1.KeySet

Required. key_set identifies the rows to be yielded. key_set names the primary keys of the rows in table to be yielded, unless index is present. If index is present, then key_set instead names index keys in index.

It is not an error for the key_set to name rows that do not exist in the database. Read yields nothing for nonexistent rows.

partitionOptions google.spanner.v1.PartitionOptions

Additional options that affect how many partitions are created.

options object <optional>

Call options. See CallOptions for more details.

read(request, optionsopt) → {Promise}

Reads rows from the database using key lookups and scans, as a simple key/value style alternative to 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 for more details.

Larger result sets can be yielded in streaming fashion by calling StreamingRead instead.

Parameters:
Name Type Attributes Description
request Object

The request object that will be sent.

Properties
Name Type Description
session string

Required. The session in which the read should be performed.

transaction google.spanner.v1.TransactionSelector

The transaction to use. If none is provided, the default is a temporary read-only transaction with strong concurrency.

table string

Required. The name of the table in the database to be read.

index string

If non-empty, the name of an index on table. This index is used instead of the table primary key when interpreting key_set and sorting result rows. See key_set for further information.

columns Array.<string>

Required. The columns of table to be returned for each row matching this request.

keySet google.spanner.v1.KeySet

Required. key_set identifies the rows to be yielded. key_set names the primary keys of the rows in table to be yielded, unless index is present. If index is present, then key_set instead names index keys in index.

If the partition_token field is empty, rows are yielded in table primary key order (if index is empty) or index key order (if index is non-empty). If the partition_token field is not empty, rows will be yielded in an unspecified order.

It is not an error for the key_set to name rows that do not exist in the database. Read yields nothing for nonexistent rows.

limit number

If greater than zero, only the first limit rows are yielded. If limit is zero, the default is no limit. A limit cannot be specified if partition_token is set.

resumeToken Buffer

If this request is resuming a previously interrupted read, resume_token should be copied from the last PartialResultSet yielded before the interruption. Doing this enables the new read to resume where the last read left off. The rest of the request parameters must exactly match the request that yielded this token.

partitionToken Buffer

If present, results will be restricted to the specified partition previously created using PartitionRead(). There must be an exact match for the values of fields common to this message and the PartitionReadRequest message used to create this partition_token.

options object <optional>

Call options. See CallOptions for more details.

rollback(request, optionsopt) → {Promise}

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 or 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.

Parameters:
Name Type Attributes Description
request Object

The request object that will be sent.

Properties
Name Type Description
session string

Required. The session in which the transaction to roll back is running.

transactionId Buffer

Required. The transaction to roll back.

options object <optional>

Call options. See CallOptions for more details.

sessionPath(project, instance, database, session) → {string}

Return a fully-qualified session resource name string.

Parameters:
Name Type Description
project string
instance string
database string
session string

streamingRead(request, optionsopt) → {Stream}

Like Read, except returns the result set as a stream. Unlike 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.

Parameters:
Name Type Attributes Description
request Object

The request object that will be sent.

Properties
Name Type Description
session string

Required. The session in which the read should be performed.

transaction google.spanner.v1.TransactionSelector

The transaction to use. If none is provided, the default is a temporary read-only transaction with strong concurrency.

table string

Required. The name of the table in the database to be read.

index string

If non-empty, the name of an index on table. This index is used instead of the table primary key when interpreting key_set and sorting result rows. See key_set for further information.

columns Array.<string>

Required. The columns of table to be returned for each row matching this request.

keySet google.spanner.v1.KeySet

Required. key_set identifies the rows to be yielded. key_set names the primary keys of the rows in table to be yielded, unless index is present. If index is present, then key_set instead names index keys in index.

If the partition_token field is empty, rows are yielded in table primary key order (if index is empty) or index key order (if index is non-empty). If the partition_token field is not empty, rows will be yielded in an unspecified order.

It is not an error for the key_set to name rows that do not exist in the database. Read yields nothing for nonexistent rows.

limit number

If greater than zero, only the first limit rows are yielded. If limit is zero, the default is no limit. A limit cannot be specified if partition_token is set.

resumeToken Buffer

If this request is resuming a previously interrupted read, resume_token should be copied from the last PartialResultSet yielded before the interruption. Doing this enables the new read to resume where the last read left off. The rest of the request parameters must exactly match the request that yielded this token.

partitionToken Buffer

If present, results will be restricted to the specified partition previously created using PartitionRead(). There must be an exact match for the values of fields common to this message and the PartitionReadRequest message used to create this partition_token.

options object <optional>

Call options. See CallOptions for more details.