Presto

Connect Cube to PrestoDB using hostname authentication together with catalog and schema selectors for your query engine layout.

Prerequisites

• The hostname for the Presto database server
• The username/password for the Presto database server
• The name of the database to use within the Presto database server

Setup

Manual

Add the following to a .env file in your Cube project:

CUBEJS_DB_TYPE=prestodb
CUBEJS_DB_HOST=my.presto.host
CUBEJS_DB_USER=presto_user
CUBEJS_DB_PASS=**********
CUBEJS_DB_PRESTO_CATALOG=my_presto_catalog
CUBEJS_DB_SCHEMA=my_presto_schema

Environment Variables

Environment Variable	Description	Possible Values	Required
CUBEJS_DB_HOST	The host URL for a database	A valid database host URL	✅
CUBEJS_DB_PORT	The port for the database connection	A valid port number	❌
CUBEJS_DB_USER	The username used to connect to the database	A valid database username	✅
CUBEJS_DB_PASS	The password used to connect to the database	A valid database password	✅
CUBEJS_DB_PRESTO_CATALOG	The catalog within Presto to connect to	A valid catalog name within a Presto database	✅
CUBEJS_DB_PRESTO_AUTH_TOKEN	The authentication token to use when connecting to Presto/Trino. It will be sent in the Authorization header.	A valid authentication token	❌
CUBEJS_DB_SCHEMA	The schema within the database to connect to	A valid schema name within a Presto database	✅
CUBEJS_DB_SSL	If true, enables SSL encryption for database connections from Cube	true, false	❌
CUBEJS_DB_MAX_POOL	The maximum number of concurrent database connections to pool. Default is 8	A valid number	❌
CUBEJS_CONCURRENCY	The number of concurrent queries to the data source	A valid number	❌
CUBEJS_DB_EXPORT_BUCKET_TYPE	The export bucket type for pre-aggregations	s3, gcs	❌
CUBEJS_DB_EXPORT_BUCKET	The export bucket to connect to	A valid bucket URL	❌
CUBEJS_DB_EXPORT_BUCKET_AWS_KEY	The AWS Access Key ID to use for export bucket writes	A valid AWS Access Key ID	❌
CUBEJS_DB_EXPORT_BUCKET_AWS_SECRET	The AWS Secret Access Key to use for export bucket writes	A valid AWS Secret Access Key	❌
CUBEJS_DB_EXPORT_BUCKET_AWS_REGION	The AWS region to use for export bucket writes	A valid AWS region	❌
CUBEJS_DB_EXPORT_GCS_CREDENTIALS	A Base64 encoded JSON key file for connecting to Google Cloud Storage	A valid Google Cloud JSON key file, encoded as a Base64 string	❌

Pre-Aggregation Feature Support

count_distinct_approx

Measures of type count_distinct_approx can be used in pre-aggregations when using Presto as a source database. To learn more about Presto support for approximate aggregate functions, click here.

Pre-Aggregation Build Strategies

To learn more about pre-aggregation build strategies, head here.

Feature	Works with read-only mode?	Is default?
Simple	✅	✅
Export Bucket	❌	❌

By default, Presto uses a simple strategy to build pre-aggregations.

Simple

No extra configuration is required to configure simple pre-aggregation builds for Presto.

Export Bucket

Presto supports using both AWS S3 and Google Cloud Storage for export bucket functionality.

AWS S3

Ensure the AWS credentials are correctly configured in IAM to allow reads and writes to the export bucket in S3.

CUBEJS_DB_EXPORT_BUCKET_TYPE=s3
CUBEJS_DB_EXPORT_BUCKET=my.bucket.on.s3
CUBEJS_DB_EXPORT_BUCKET_AWS_KEY=<AWS_KEY>
CUBEJS_DB_EXPORT_BUCKET_AWS_SECRET=<AWS_SECRET>
CUBEJS_DB_EXPORT_BUCKET_AWS_REGION=<AWS_REGION>

Google Cloud Storage

When using an export bucket, remember to assign the Storage Object Admin role to your Google Cloud credentials (CUBEJS_DB_EXPORT_GCS_CREDENTIALS).

CUBEJS_DB_EXPORT_BUCKET=gs://presto-export-bucket
CUBEJS_DB_EXPORT_BUCKET_TYPE=gcs
CUBEJS_DB_EXPORT_GCS_CREDENTIALS=<BASE64_ENCODED_SERVICE_CREDENTIALS_JSON>

SSL

To enable SSL-encrypted connections between Cube and Presto, set the CUBEJS_DB_SSL environment variable to true. For more information on how to configure custom certificates, please check out Enable SSL Connections to the Database.

Custom headers

The Presto driver supports forwarding custom HTTP headers on every request to the Presto coordinator. This is useful for setting headers like X-Presto-Source, X-Presto-Client-Tags, or any other custom header your Presto coordinator expects.

Custom headers can’t be configured via environment variables. Instead, use the driver_factory configuration option to pass a headers object to the driver:

Python

from cube import config

@config('driver_factory')
def driver_factory(ctx: dict) -> dict:
  return {
    'type': 'prestodb',
    'headers': {
      'X-Presto-Source': 'cube',
      'X-Presto-Client-Tags': 'user=[e-mail]'
    }
  }

module.exports = {
  driverFactory: ({ dataSource }) => ({
    type: "prestodb",
    headers: {
      "X-Presto-Source": "cube",
      "X-Presto-Client-Tags": "user=[e-mail]"
    }
  })
};

In multitenant deployments, you can use the security context to pass per-tenant headers, for example to forward a user token from the API request down to Presto:

Python

from cube import config

@config('driver_factory')
def driver_factory(ctx: dict) -> dict:
  security_context = ctx['securityContext']
  return {
    'type': 'prestodb',
    'headers': {
      'X-Presto-Client-Tags': f"user={security_context['user_id']}",
      'X-Custom-User-Token': security_context['token']
    }
  }

module.exports = {
  driverFactory: ({ securityContext }) => ({
    type: "prestodb",
    headers: {
      "X-Presto-Client-Tags": `user=${securityContext.user_id}`,
      "X-Custom-User-Token": securityContext.token
    }
  })
};