Sample01_Authentication.md

Authentication

This sample demonstrates how to authenticate TandemClient which is starting point for interaction with Tandem using REST API.

Tandem using using access token which can be obtained using APS Authentication service. Both 2-legged and 3-legged token are supported.

Configuring Tandem

Before accessing Tandem REST API it's necessary to enable access for your service. This can be done either on facility level or on account level.

Follow steps below to enable access on facility level:

1. Open facility.
2. One the left side click Users to open User Management Panel.
3. Select Service under Invite user / service to this facility.
4. Enter client ID of your service.
5. Specify permission for your service.
6. Click Add to save changes.

Authenticate the client

When creating instance of TandenClient class you need to provide deletage to function which provides access token, i.e.:

var client = new TandemClient(() => GetToken());

The GetToken function should provide valid access token. Usually this is done by calling POST token endpoint = in example below this is done by GetAccessToken function:

string GetToken()
{
    // obtain access token
    var token = GetAccessToken().ConfigureAwait(false).GetAwaiter().GetResult();

    return token.AccessToken;
}

Authenticate using 2-legged access token

2-legged access token is usually used for server to server scenarios - i.e. automated processing of data without end user input - see more details here.

To create 2-legged token you can utilize pre-built class TwoLeggedAuth - this takes three parameters:

• clientID - client ID of the APS application.
• clientSecret- client secret of the APS application.
• scope - concated string of scopes

The class provides GetToken method which returns access token:

// replace YOUR_CLIENT_ID, YOUR_CLIENT_SECRET with your own credentials
var auth = new TwoLeggedAuth("YOUR_CLIENT_ID",
  "YOUR_CLIENT_SECRET",
  "data:read data:write");
var client = new TandemClient(() => auth.GetToken());