BigQuery Connector

With this connector, Hasura allows you to instantly create a real-time GraphQL API on top of your data models in BigQuery. This connector supports BigQuery's functionalities listed in the table below, allowing for efficient and scalable data operations. Additionally, users benefit from all the powerful features of Hasura’s Data Delivery Network (DDN) platform, including query pushdown capabilities that delegate query operations to the database, thereby enhancing query optimization and performance.

This connector implements the Data Connector Spec.

• Connector information in the Hasura Hub
• Hasura V3 Documentation

Features

Below, you'll find a matrix of all supported features for the BigQuery connector:

Feature	Supported	Notes
Native Queries + Logical Models	❌
Native Mutations	❌
Simple Object Query	✅
Filter / Search	✅
Simple Aggregation	✅
Sort	✅
Paginate	✅
Table Relationships	❌
Views	✅
Remote Relationships	✅
Custom Fields	❌
Mutations	❌
Distinct	❌
Enums	❌
Naming Conventions	❌
Default Values	❌
User-defined Functions	❌

Prerequisites

1. Create a Hasura Cloud account
2. Please ensure you have the DDN CLI and Docker installed
3. Create a supergraph
4. Create a subgraph

The steps below explain how to initialize and configure a connector on your local machine (typically for development purposes).You can learn how to deploy a connector to Hasura DDN — after it's been configured — here.

Using the BigQuery connector

With the context set for an existing subgraph, initialize the connector:

ddn connector init -i

When the wizard runs, you'll be prompted to enter the following env vars necessary for your connector to function:

Name	Description	Required
JDBC_URL	The JDBC URL to connect to the database	Yes

After the CLI initializes the connector, you'll need to:

Configuring your JDBC connection string

The official BigQuery JDBC driver is used. You can find documentation on configuring the JDBC connection string here. As an example using a service account with a full key file downloaded from google:

APP_FOO_JDBC_URL=jdbc:bigquery://https://www.googleapis.com/bigquery/v2:443;ProjectId=project-id;DefaultDataset=dataset;OAuthType=0;OAuthServiceAcctEmail=service-account-email;OAuthPvtKey=/etc/connector/key.json;

Note: ProjectId and DefaultDataset are required in your JDBC connection string. Note: since the files get mounted in docker it is import the file path is /etc/connector/<your-key-file>.json

Make sure you place you key.json in the connector folder /<subgraph>/connector/<connectorname>/key.json. The key should be the full key downloaded from google cloud console that looks like:

{
  "type": "service_account",
  "project_id": "project-id",
  "private_key_id": "private-key-id",
  "private_key": "-----BEGIN PRIVATE KEY-----\nprivate-key\n-----END PRIVATE KEY-----\n",
  "client_email": "service-account-email",
  "client_id": "client-id",
  "auth_uri": "https://accounts.google.com/o/oauth2/auth",
  "token_uri": "https://oauth2.googleapis.com/token",
  "auth_provider_x509_cert_url": "https://www.googleapis.com/oauth2/v1/certs",
  "client_x509_cert_url": "https://www.googleapis.com/robot/v1/metadata/x509/service-account-email"
}

Once that is done you'll need to:

• Introspect the source.
• Add your models, commands, and relationships.
• Create a new build.
• Test it by running your project along with the connector.

License

The Hasura BigQuery connector is available under the Apache License 2.0.