Gmail Subscriptions

OneGraph supports GraphQL subscriptions for new messages on Gmail. Follow the steps below to enable them.

Step 1

Follow the instructions to create a custom OAuth client for Gmail.

Step 2

Enable the Gmail API on the Google Cloud console.

Step 3

Google requires a Google Cloud pub/sub topic to receive notifications about new Gmail messages.

Create a new pull pub/sub topic on Google Cloud with topic id "onegraph-gmail".

Grant gmail-api-push@system.gserviceaccount.com the role of Pub/Sub Publisher on the pubsub topic so that gmail can push messages to it.

Step 4

Set the pubsub topic name (e.g. projects/YOUR_PROJECT_NAME/topics/onegraph-gmail) in the custom OAuth client form for Gmail from step 1.

Step 5

Create a new cloud function that will forward messages to OneGraph.

Set the configuration to the following:

Name

onegraph-gmail

Memory allocated

128 MB

Trigger

Cloud Pub/Sub

Topic

onegraph-gmail

Source code

Inline editor

Runtime

Node.js 10 (Beta)

index.js

const https = require('https');

exports.pubSubForwarder = (event, context) => {
  return new Promise((resolve, reject) => {
    try {
      const bodyJson = JSON.stringify({
        data: event.data,
        messageId: context.eventId,
        publishTime: context.timestamp,
      });
      const body = Buffer.from(bodyJson, 'utf-8');
      const options = {
        hostname: 'serve.onegraph.com',
        port: 443,
        path: '/webhooks/gmail/watch',
        method: 'POST',
        headers: {
          'Content-Type': 'application/json',
          'Content-Length': body.length,
        },
      };
      const req = https.request(options, (res) => {
        res.on('data', (d) => console.log('Response:', d.toString('utf-8')));
        res.on('error', (e) => {
          console.error('error posting message to OneGraph', e);
          reject(e);
        });
        res.on('end', () => {
          if (res.statusCode != 200) {
            console.error('Got non-200 status code', res.statusCode);
            reject(new Error('Error forwarding request to OneGraph'));
          } else {
            console.log('Successfully forwarded request to OneGraph');
            resolve();
          }
        });
      });
      req.on('error', (e) => {
        console.error('error posting message to OneGraph', e);
        callback(e);
      });
      req.write(body);
      req.end();
    } catch (e) {
      reject(e);
    }
  });
};

Function to execute

pubSubForwarder

Click create.

Step 6

Go to the Data Explorer tab on the OneGraph dashboard and run the following subscription:

subscription GmailNewMessage {
  gmail {
    newMessage {
      id
      snippet
    }
  }
}

Every time you receive a new message on Gmail, you will get a GraphQL response:

{
  "data": {
    "gmail": {
      "newMessage": {
        "id": "170ea4ad7bf928327",
        "snippet": "Test On Tue, Mar 17, 2020 at 1:58 PM Daniel Woelfel <daniel@example.com> wrote: New message"
      }
    }
  },
  "extensions": {
    "eventId": "e8efce56-4ee2-4dd2-81c8-f4e51e018f40",
    "subscriptionId": "2e355868-13bd-44cf-b609-7954ede17729"
  }
}