To create data sources on headless servers or other machines on which the adapter cannot open a browser, you need to authenticate from another machine. Authentication is a two-step process.

1. Instead of installing the adapter on another machine, you can follow the steps below to obtain the OAuthVerifier value. Or, you can install the adapter on another machine and transfer the OAuth authentication values, after you authenticate through the usual browser-based flow.
2. You can then configure the adapter to automatically refresh the access token from the headless machine.

You can follow the headless OAuth authentication flow using the adapter's embedded OAuth credentials or using the OAuth credentials for your custom OAuth app.

Using the Credentials for a Custom OAuth App

Create a Custom OAuth App

See Creating a Custom OAuth App for a procedure. This section describes the procedure to authenticate and connect to data.

Obtain a Verifier Code

First, set the following properties on the headless machine:

• InitiateOAuth: Set to OFF.
• OAuthClientId: Set to the App ID in your app settings.
• OAuthClientSecret: Set to the App Secret in your app settings.

Next, authenticate from another machine and obtain the OAuthVerifier connection property:

1. Call the GetOAuthAuthorizationURL stored procedure with the CallbackURL input parameter set to the exact Redirect URI you specified in your app settings.
2. Open the returned URL in a browser. Log in and grant permissions to the adapter. You are then redirected to the callback URL, which contains the verifier code.
3. Save the value of the verifier code. You need to set this in the OAuthVerifier connection property.

Finally, on the headless machine, set the following connection properties to obtain the OAuth authentication values:

• OAuthClientId: Set to the client key in your app settings.
• OAuthClientSecret: Set to the client secret in your app settings.
• OAuthVerifier: Set to the verifier code.
• OAuthSettingsLocation: Set to persist the encrypted OAuth authentication values to the specified file.
• InitiateOAuth: Set to REFRESH.

Connect to Data

After the OAuth settings file is generated, set the following properties to connect to data:

• OAuthSettingsLocation: Set to the file containing the encrypted OAuth authentication values. Make sure this file gives read and write permissions to the provider to enable the automatic refreshing of the access token.
• InitiateOAuth: Set to REFRESH.

Transfer OAuth Settings

To install the adapter on another machine, authenticate, and then transfer the resulting OAuth values:

1. On a second machine, install the adapter and connect with the following properties set:
   • OAuthSettingsLocation: Set to a writable text file.
   • InitiateOAuth: Set to GETANDREFRESH.
   • OAuthClientId: Set to the Client ID in your app settings.
   • OAuthClientSecret: Set to the Client Secret in your app settings.
   • CallbackURL: Set to the Callback URL in your app settings.
2. Test the connection to authenticate. The resulting authentication values are written, encrypted, to the path specified by OAuthSettingsLocation. Once you have successfully tested the connection, copy the OAuth settings file to your headless machine. On the headless machine, set the following connection properties to connect to data:
   • InitiateOAuth: Set to REFRESH.
   • OAuthSettingsLocation: Set to the path to your OAuth settings file. Make sure this file gives read and write permissions to the adapter to enable the automatic refreshing of the access token.