Authentication with Google

Prerequisites

Before configuring Catena to authenticate users with Google, you must register an application in the Google API console.

The authorization callback URL should be set to the PlatformUrl plus the RedirectUri for PROVIDER_GOOGLE_WEB. If there is a difference between the value configured in the Google API console and the one sent by Catena (from its configuration), then Google will display an error ("Error 400: redirect_uri_mismatch") instead of an authorization page.

You will need the "client_id" and "client_secret" from the API console to configure Catena.

Catena configuration

Open the appsettings for your environment and look for the Catena authentication service configuration section which contains a section for Google (PROVIDER_GOOGLE_WEB). If the section does not exist, you may need to create it.

Fill ClientID and ClientSecret with the values from the Google API console. Set the RedirectUri to the one shown in the example below as a starting point and make sure IsEnabled is set to true.

For example, in appsettings.Development.json:

{
  "Catena": {
    "Authentication": {
      "Validators": {
        "PROVIDER_GOOGLE_WEB": {
          "ClientID": "<your client ID>",
          "ClientSecret": "<your client secret>",
          "RedirectUri": "/api/v1/authentication/PROVIDER_GOOGLE_WEB/callback",
          "IsEnabled": true
        }
      }
    }
  }
}

Make sure your appsettings.Development.json is added to .gitignore

Setting secrets in production

For a live production deployment, you don't want to expose your secrets in the appsettings file.

Catena provides 2 potential solutions for this.

• Inline Encryption - This allows you to encrypt values in your appsettings.json so it can be commited and shared across the team with only one shared password stored offline.
• Configuring Dokku Secrets - Using dokku, setup environment variables that are read in by the app

When using Dokku secrets, you can map the nested JSON values to a new environment variable.

For example, ClientID maps too:

Catena__Authentication__Validators__PROVIDER_GOOGLE_WEB__ClientID

Then Client Secret maps too:

Catena__Authentication__Validators__PROVIDER_GOOGLE_WEB__ClientSecret

If deploying via the AWS deployment guide, add these to your dokku-secrets.env file and run ./set-dokku-secrets.sh. For more details and instructions on how to rotate secrets, view the Secrets management page.