Heroku External Objects
Last updated 08 August 2017
Heroku External Objects is available as part of Heroku Connect. It provides an OData wrapper for a Heroku Postgres database that has been configured for use with Heroku Connect. This feature allows other web services to retrieve data from within the specified Heroku Postgres database using RESTful endpoints generated by the wrapper. Read/write support is available via OData 4.0 for tables only; writing back to views is not currently supported.
Support for views is currently in beta. Unlike tables, views do not support writes.
Used in tandem with Salesforce Connect, the feature permits data in a Heroku Postgres database to be represented in a Salesforce deployment, where it can be viewed (including within Apex and Visualforce pages), searched, and related to other objects. It cannot be used in standard reports as the data is available by reference.
Service Authentication
External Objects service endpoints are protected by basic authentication. Once the service is enabled, credentials can be viewed, reset, and revoked from the External Objects settings page.
Resource Configuration
When the External Objects service is active for a connection, a list of available tables and views will appear in the External Objects settings page. Tables and views across all schemas within the associated connection’s database will be available, including those schema not actively managed by Heroku Connect as part of the bi-directional synchronization service. Any of these tables or views can be enabled or disabled as a resource in the External Objects service by clicking its checkbox from the settings page.
Tables must contain a primary key to be enabled as an External Objects resource.
Rate limits
The External Objects service is rate-limited at 10,000 requests per service, per hour for the danketsu (paid) plan; rate limits can be increased on request. For the demo plan, the limit is 1,000 requests per service, per hour. Attempting to access services after this limit has been reached will result in 429 Too Many Requests. The response message will also contain information about when to expect to be able to make another API request. Rate limit throttles reset at the top of each hour.
{"message":"Request was throttled. Expected available in 1000.0 seconds."}