kurrier
Configuring Providers

Google

Connecting your Google account

Google

Kurrier can connect directly to your Google (Gmail) account using Google's secure OAuth sign-in flow.

Unlike SMTP/IMAP, no app passwords, server names, or API keys are required.

Make sure to have

OIDC_GOOGLE_CLIENT_ID

OIDC_GOOGLE_CLIENT_SECRET

set in your environment variables before connecting your Google account.


3. Self-Hosting with Your Own Google OAuth App

If you're self-hosting Kurrier, you'll need to create your own Google OAuth application.

Create a Google Cloud Project

  1. Visit the Google Cloud Console:

https://console.cloud.google.com/

  1. Create a new project (or select an existing one).

  2. Enable the Gmail API for your project.

  3. Configure the OAuth Consent Screen.

  4. Create an OAuth 2.0 Client ID for a Web Application.

  5. Configure the redirect URI to point to your Kurrier instance.

For example:


https://mail.example.com/api/oauth/google/callback

Replace the domain with your own Kurrier installation.


4. Required OAuth Scopes

Kurrier requires the following Google OAuth scopes:

| Scope | Purpose |

|--------|---------|

| openid | Authenticate the user |

| email | Read the connected email address |

| profile | Basic profile information |

| https://www.googleapis.com/auth/gmail.modify | Read emails, modify labels, archive, trash, mark read/unread |

| https://www.googleapis.com/auth/gmail.send | Send emails |

These are the minimum permissions required for a complete Gmail experience.


1. Overview

When you connect a Google account, Kurrier uses the official Gmail API to:

  • Send emails
  • Sync your inbox
  • Sync folders and labels
  • Track read/unread status
  • Receive new emails
  • Keep your mailbox synchronized automatically

Your Google password is never stored by Kurrier. Authentication is handled entirely through Google OAuth.


2. Connecting Your Google Account

In Kurrier, go to:

Dashboard → Providers → Add Provider → Google

Click:

Sign in with Google

You'll be redirected to Google's secure authentication page.

After signing in and granting permission, you'll be returned to Kurrier automatically.

Once connected, the provider will display a Verified status.


3. Required Permissions

Kurrier requests the minimum Google permissions required to provide a complete email experience.

These permissions allow Kurrier to:

  • Read your mailbox
  • Send emails on your behalf
  • Create, modify and delete drafts
  • Read and manage labels
  • Keep your mailbox synchronized

Kurrier only accesses the Google account(s) that you explicitly connect.


4. Verification

After connecting your account, Kurrier automatically verifies the connection by communicating with the Gmail API.

If successful, the provider card will display:

  • ✅ Verified
  • Connected Google email address
  • Mailbox information

5. Disconnecting

You can disconnect your Google account at any time by removing the identity from Kurrier.

If you would also like to revoke Kurrier's access completely, visit:

https://myaccount.google.com/permissions

Locate Kurrier in the list of connected applications and choose Remove Access.


6. Troubleshooting

Authentication failed

Try signing in again and ensure you complete the Google consent flow.

Permission denied

If you denied one or more permissions, remove the existing connection and reconnect the account.

Account disconnected

If your Google refresh token is revoked or expires, Kurrier will notify you that the provider needs to be reconnected.


7. Why use Google instead of SMTP?

Using the Gmail API provides several advantages over SMTP/IMAP:

  • No App Passwords required
  • Secure OAuth authentication
  • Automatic token refresh
  • Better Gmail compatibility
  • Reliable mailbox synchronization
  • Supports Gmail labels natively

For Gmail accounts, connecting through Google is the recommended option over SMTP/IMAP.