Custom OAuth client for Google services

To use Google services like Gmail, YouTube, Google Calendar, and Google Docs with OneGraph, we require that you create a custom OAuth client.

First, create or update your consent screen on the Google Cloud Platform console.

Make sure that onegraph.com is set as an authorized domain.

Go to the Credentials page to create a new OAuth client.

Choose "Web application" as the "Application type" and add the following Authorized redirect URIs, depending on the services that you want to use. You can leave the "Authorized JavaScript origins" field blank.

Service	Redirect URI
Gmail	https://serve.onegraph.com/oauth/gmail/receive
Google Analytics	https://serve.onegraph.com/oauth/google-analytics/receive
Google Calendar	https://serve.onegraph.com/oauth/google-calendar/receive
Google Docs/Drive	https://serve.onegraph.com/oauth/google-docs/receive
Google Translate	https://serve.onegraph.com/oauth/google-translate/receive
YouTube	https://serve.onegraph.com/oauth/youtube/receive

Copy your client id and client secret.

Enter them on the OneGraph dashboard for your app under Auth Services > Custom OAuth.

Now you and your users can log in with your custom Google Client.

If you would help getting your Google app verified, please email support@onegraph.com.

Gmail Subscriptions

OneGraph supports GraphQL subscriptions for new messages on Gmail.

There are a few extra steps to set up subscriptions with OneGraph.

Step 1

Follow the instructions above 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(
  $webhookUrl: String! = "https://serve.onegraph.com/dev/null"
) {
  gmail(webhookUrl: $webhookUrl) {
    newMessage {
      id
      snippet
    }
  }
}

Replace the webhookUrl param with the url that you would like the message to be posted to. If you need a webhook url to test, you can use WebSmee.

Every time you receive a new message on Gmail, the webhook url will be called with the GraphQL response from your subscription:

{
  "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"
  }
}