Custom Google OAuth Credentials

Aerion ships with its own OAuth credentials so that Gmail works out of the box, but you can also bring your own. This guide walks you through creating a Google Cloud project and using its OAuth Client ID and Secret for everything in one shot — Gmail, the Calendar extension, and the Contacts extension.

Why you might want this

• The Contacts and Calendar extensions currently use a temporary Google testing project by default (see Google & Microsoft Credentials). With your own project, the extensions authenticate against a project you control.
• Your mail, calendar, and contacts all flow through your own Google Cloud project instead of a shared one.

1. Create a Google Cloud Project

1. Go to the Google Cloud Console and sign in with your Google account
2. Click the project picker at the top of the page (next to the Google Cloud logo)
3. Click New Project
4. Enter a project name (e.g. "Aerion") — the organization/location can be left as-is for personal accounts
5. Click Create
6. Once created, make sure the new project is selected in the project picker

2. Enable the APIs

Aerion talks to Gmail over IMAP/SMTP, but the Calendar and Contacts extensions use Google's APIs, which must be enabled per project:

1. In the console, go to APIs & Services → Library
2. Search for and Enable each of the following:
   • Gmail API
   • Google Calendar API
   • Google People API (used for contacts)

3. Configure the OAuth Consent Screen

1. Go to APIs & Services → OAuth consent screen (Google may also call this Google Auth Platform)
2. If prompted, click Get started and fill in:
   • App name: e.g. "Aerion"
   • User support email: your email address
   • Audience: External
   • Contact information: your email address
3. Agree to the policy and click Create

Publish the App

Under Audience, click Publish app to move the app from Testing to In production.

Why publish?

Google expires the refresh tokens of apps left in Testing status after 7 days, which would force you to re-authorize every week. Publishing avoids this. Your app remains private to your project — publishing does not list it anywhere.

Since the app is published without going through Google's verification process, you will see a "This app isn't verified" warning when authorizing — this is the same warning described in the Gmail Setup Security Note, except this time the unverified app is your own project. Click Advanced → Go to Aerion (unsafe) → Allow to proceed.

You can also add your own Google accounts as test users under Audience → Test users.

4. Add the Scopes

1. Go to APIs & Services → OAuth consent screen → Data Access (or Google Auth Platform → Data Access)
2. Click Add or remove scopes
3. Add the following scopes:

Scope	Used For
https://mail.google.com/	Full Gmail access over IMAP/SMTP (Mail)
https://www.googleapis.com/auth/contacts.readonly	Contact sync for autocomplete (Mail) and reading contacts (Contacts extension)
https://www.googleapis.com/auth/contacts.other.readonly	"Other contacts" for email autocomplete (Mail)
https://www.googleapis.com/auth/contacts	Editing contacts — only needed if you enable write access in the Contacts extension
https://www.googleapis.com/auth/calendar	Reading and writing calendar events (Calendar extension)
https://www.googleapis.com/auth/userinfo.email	Identifying which account you authorized
openid	OpenID Connect sign-in

4. Click Update, then Save

5. Create the OAuth Client ID and Secret

1. Go to APIs & Services → Credentials (or Google Auth Platform → Clients)
2. Click Create Credentials → OAuth client ID (or Create client)
3. For Application type, select Desktop app
4. Enter a name (e.g. "Aerion Desktop") and click Create
5. Copy the Client ID and Client Secret shown — you'll paste both into Aerion next

6. Configure Aerion — Mail

1. In Aerion, open Settings → Accounts (tab)
2. Scroll to the bottom where OAuth Credentials is located and expand it
3. Under Google Mail, select Custom from the dropdown menu
4. Copy and paste the Client ID and Client Secret into their respective fields and save

If you already added your Gmail account, re-authorize it so it starts using your credentials: Settings → Accounts → Edit on the account → Re-authorize. Otherwise just add your account with OAuth as usual.

7. Configure the Calendar Extension

Extensions are disabled by default, so enable it first:

1. Go to Settings → Extensions (tab) and toggle Calendar on
2. Click the Edit button of the extension
3. Scroll down to OAuth Credentials (advanced) and expand it
4. Under Google, select Custom from the dropdown menu
5. Copy and paste the same Client ID and Client Secret there too, and save

8. Configure the Contacts Extension

Repeat the same steps for the Contacts extension:

1. Go to Settings → Extensions (tab) and toggle Contacts on
2. Click the Edit button of the extension
3. Scroll down to OAuth Credentials (advanced) and expand it
4. Under Google, select Custom from the dropdown menu
5. Copy and paste the same Client ID and Client Secret, and save

Done

Mail, Calendar, and Contacts now all authenticate through your own Google Cloud project. Note that each of them keeps its own authorization — the first time each one connects to Google after the switch, you'll be asked to sign in and consent again (including the unverified-app warning described above).