BigQueryStorageClient

BigQueryStorageClient

BigQuery storage API.

The BigQuery storage API can be used to read data stored in BigQuery.

The v1beta1 API is not yet officially deprecated, and will go through a full deprecation cycle (https://cloud.google.com/products#product-launch-stages) before the service is turned down. However, new code should use the v1 API going forward.

Constructor

new BigQueryStorageClient(optionsopt, gaxInstanceopt)

Construct an instance of BigQueryStorageClient.

Parameters:
Name Type Attributes Description
options object <optional>

The configuration object. The options accepted by the constructor are described in detail in this document. The common options are:

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.

clientConfig gax.ClientConfig <optional>

Client configuration override. Follows the structure of gapicConfig.

fallback boolean <optional>

Use HTTP/1.1 REST mode. For more information, please check the documentation.

gaxInstance gax <optional>

loaded instance of google-gax. Useful if you need to avoid loading the default gRPC version and want to use the fallback HTTP implementation. Load only fallback version and pass it to the constructor: const gax = require('google-gax/build/src/fallback'); // avoids loading google-gax with gRPC const client = new BigQueryStorageClient({fallback: true}, gax);

Members

apiEndpoint

The DNS address for this API service.

apiEndpoint

The DNS address for this API service - same as servicePath.

port

The port for this API service.

scopes

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

servicePath

The DNS address for this API service.

Methods

close() → {Promise}

Terminate the gRPC channel and close the client.

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

Returns:
Type Description
Promise

A promise that resolves when the client is closed.

getProjectId() → {Promise}

Return the project ID used by this class.

Returns:
Type Description
Promise

A promise that resolves to string containing the project ID.

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.

Returns:
Type Description
Promise

A promise that resolves to an authenticated service stub.

matchLocationFromReadSessionName(readSessionName) → {string}

Parse the location from ReadSession resource.

Parameters:
Name Type Description
readSessionName string

A fully-qualified path representing ReadSession resource.

Returns:
Type Description
string

A string representing the location.

matchLocationFromStreamName(streamName) → {string}

Parse the location from Stream resource.

Parameters:
Name Type Description
streamName string

A fully-qualified path representing Stream resource.

Returns:
Type Description
string

A string representing the location.

matchProjectFromProjectName(projectName) → {string}

Parse the project from Project resource.

Parameters:
Name Type Description
projectName string

A fully-qualified path representing Project resource.

Returns:
Type Description
string

A string representing the project.

matchProjectFromReadSessionName(readSessionName) → {string}

Parse the project from ReadSession resource.

Parameters:
Name Type Description
readSessionName string

A fully-qualified path representing ReadSession resource.

Returns:
Type Description
string

A string representing the project.

matchProjectFromStreamName(streamName) → {string}

Parse the project from Stream resource.

Parameters:
Name Type Description
streamName string

A fully-qualified path representing Stream resource.

Returns:
Type Description
string

A string representing the project.

matchSessionFromReadSessionName(readSessionName) → {string}

Parse the session from ReadSession resource.

Parameters:
Name Type Description
readSessionName string

A fully-qualified path representing ReadSession resource.

Returns:
Type Description
string

A string representing the session.

matchStreamFromStreamName(streamName) → {string}

Parse the stream from Stream resource.

Parameters:
Name Type Description
streamName string

A fully-qualified path representing Stream resource.

Returns:
Type Description
string

A string representing the stream.

projectPath(project) → {string}

Return a fully-qualified project resource name string.

Parameters:
Name Type Description
project string
Returns:
Type Description
string

Resource name string.

readRows(request, optionsopt) → {Stream}

Reads rows from the table in the format prescribed by the read session. Each response contains one or more table rows, up to a maximum of 10 MiB per response; read requests which attempt to read individual rows larger than this will fail.

Each request also returns a set of stream statistics reflecting the estimated total number of rows in the read stream. This number is computed based on the total table size and the number of active streams in the read session, and may change as other streams continue to read data.

Parameters:
Name Type Attributes Description
request Object

The request object that will be sent.

Properties
Name Type Description
readPosition google.cloud.bigquery.storage.v1beta1.StreamPosition

Required. Identifier of the position in the stream to start reading from. The offset requested must be less than the last row read from ReadRows. Requesting a larger offset is undefined.

options object <optional>

Call options. See CallOptions for more details.

Returns:
Type Description
Stream

An object stream which emits ReadRowsResponse on 'data' event. Please see the documentation for more details and examples.

Example
  /**
   * This snippet has been automatically generated and should be regarded as a code template only.
   * It will require modifications to work.
   * It may require correct/in-range values for request initialization.
   * TODO(developer): Uncomment these variables before running the sample.
   */
  /**
   *  Required. Identifier of the position in the stream to start reading from.
   *  The offset requested must be less than the last row read from ReadRows.
   *  Requesting a larger offset is undefined.
   */
  // const readPosition = {}

  // Imports the Storage library
  const {BigQueryStorageClient} = require('@google-cloud/bigquery-storage').v1beta1;

  // Instantiates a client
  const storageClient = new BigQueryStorageClient();

  async function callReadRows() {
    // Construct request
    const request = {
      readPosition,
    };

    // Run request
    const stream = await storageClient.readRows(request);
    stream.on('data', (response) => { console.log(response) });
    stream.on('error', (err) => { throw(err) });
    stream.on('end', () => { /* API call completed */ });
  }

  callReadRows();

readSessionPath(project, location, session) → {string}

Return a fully-qualified readSession resource name string.

Parameters:
Name Type Description
project string
location string
session string
Returns:
Type Description
string

Resource name string.

streamPath(project, location, stream) → {string}

Return a fully-qualified stream resource name string.

Parameters:
Name Type Description
project string
location string
stream string
Returns:
Type Description
string

Resource name string.