0

I have PostgreSQL sitting on Heroku and I will have to pull the data from Heroku into apex and display the data on VF page. Anybody can guide me how/where should I start from?

Improve this question
2
  • You can use the lightning connect / Heroku connect to get the data from the postgres db on heorku. Once the connection is established then the getting the data is as simple as writing an SOQl query.
    – Sam
    Commented Apr 28, 2016 at 3:06
  • yes i know that once the connection is established it will be simple but my question how do i connect?
    – Nick
    Commented Apr 28, 2016 at 3:17

1 Answer 1

Reset to default
2

Use the Heroku Connect API:

  1. Create a Heroku app and Heroku PostgreSQL database
  2. Create the Heroku Connect add-on
  3. Link the new add-on to your Heroku user account
  4. Retrieve the new connection's ID
  5. Configure the database key and schema for the connection
  6. Authenticate the connection to your Salesforce Org
  7. Import a mapping configuration
  8. Monitor the connection and mapping status

Then write the Apex code:

With the REST endpoint on Heroku ready to be consumed, it's now just a matter of writing some Apex code to bridge between Salesforce Connect and the service. For the example real estate REST service, we could have a simple Apex adapter that extends the DataSource.Connection class and implements the sync(), query(), and search() methods with a basic structure like:

    global class RealEstateConnection extends DataSource.Connection {
        override global List search(DataSource.SearchContext searchContext) { }
        override global List sync() { }
        override global DataSource.TableResult query(DataSource.QueryContext queryContext) { }
    }

or create a trigger bound to an Apex callout:

The trigger can use an Apex callout to make a REST JSON call to an endpoint on a Heroku app. For instance, here is an Apex trigger that calls a Heroku app:

 trigger NewContactWebhookTrigger on Contact (after insert) {
  String url = 'https://foo.herokuapp.com/new_contact';
  String content = Webhook.jsonContent(Trigger.new, Trigger.old);
  Webhook.callout(url, content);
}

The referenced Webhook Apex class is:

 public class Webhook {
  public static String jsonContent(List triggerNew, List triggerOld) {
    String newObjects = '[]';
    if (triggerNew != null) {
      newObjects = JSON.serialize(triggerNew);
    }
    String oldObjects = '[]';
    if (triggerOld != null) {
      oldObjects = JSON.serialize(triggerOld);
    }
    String userId = JSON.serialize(UserInfo.getUserId());
    String content = '{"new": ' + newObjects + ', "old": ' + oldObjects + ', "userId": ' + userId + '}';
    return content;
  }
  @future(callout=true) public static void callout(String url, String content) {
    Http h = new Http();
    HttpRequest req = new HttpRequest();
    req.setEndpoint(url);
    req.setMethod('POST');
    req.setHeader('Content-Type', 'application/json');
    req.setBody(content);
    h.send(req);
  }
}

References

Improve this answer

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .