# Obtaining A Session

{% hint style="warning" %}
Prior to connecting to any API, your administrator should setup an Application identity and a Device identity (if not using two-way TLS).
{% endhint %}

## Application / Client Session

A client-credentials session is used whenever your application will be interacting with the SanteDB system without user interaction. This is primarily intended for back-end processes, system integrations, etc.

To request a client-credentials session you will need:

* Your `client_id` and your `client_secret` provided by your system administrator
* Either:
  * A client certificate which is used to authenticate the node you're using, or
  * A `device_id` and a `device_secret` provided by your system administrator.

To authenticate, first, take your device credentials and encode them as a base64 payload, for example if you device id is `EXAMPLE_DEVICE_NODE` and the secret is `qlcEtboF-H5XdK4x1t-arL5GaG4svF9TkL5a` , your device authentication header would be : `RVhBTVBMRV9ERVZJQ0VfTk9ERTpxbGNFdGJvRi1INVhkSzR4MXQtYXJMNUdhRzRzdkY5VGtMNWE=`

Next, locate your application credentials. These are generated by your system administrator, this example will use client\_id of `EXAMPLE_APPLICATION` with secret `4toXrw0x-SpM1K4c7D$M0OkJcA1OgW4HeOlV`

Next, construct an HTTP POST request to the endpoint \<root>/auth/oauth2\_token , setting the X-Device-Authorization header and the appropriate OAUTH payload:

```http
POST http://mpi-test.local:8080/auth/oauth2_token HTTP/1.1
User-Agent: Fiddler
X-Device-Authorization: BASIC RVhBTVBMRV9ERVZJQ0VfTk9ERTpxbGNFdGJvRi1INVhkSzR4MXQtYXJMNUdhRzRzdkY5VGtMNWE=
Content-Type: application/x-www-form-urlencoded
Host: mpi-test.local:8080
Content-Length: 118

grant_type=client_credentials&scope=*&client_id=EXAMPLE_APPLICATION&client_secret=4toXrw0x-SpM1K4c7D$M0OkJcA1OgW4HeOlV
```

The server will respond with a series of tokens:

```http
HTTP/1.1 200 OK
Content-Length: 1307
Content-Type: application/json
Server: Microsoft-HTTPAPI/2.0
Date: Mon, 11 Jan 2021 17:16:03 GMT

{
     "access_token":"E878ABAE3054EB11AFFD00155D640B2349E9BDE39EBC9082EE1D45358EC838D18122DF3FC1EFE649858826108F5881C6",
     "id_token":"eyJ0eXAiOiJK...8Ou0",
     "token_type":"bearer",
     "expires_in":1799984,
     "refresh_token":"C03E7137B9998D4584325D8EA7D393F83CFD5F4FA877393BFB280FBE3D0A7A963667E676B6A1ED3357CE2A1B57742D2B"
}
```

Your application should store the access\_token somewhere in memory as this will need to be attached to all your requests.&#x20;

{% hint style="info" %}
You can decode the id\_token to get key information about the session granted such as policies, permissions, expiration time, etc.
{% endhint %}

## Using the Access\_Token

The access\_token is attached to each subsequent request as a BEARER token session

```http
User-Agent: Fiddler
Authorization: bearer E878ABAE3054EB11AFFD00155D640B2349E9BDE39EBC9082EE1D45358EC838D18122DF3FC1EFE649858826108F5881C6
```


---

# Agent Instructions: Querying This Documentation

If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question.

Perform an HTTP GET request on the current page URL with the `ask` query parameter:

```
GET https://help.santesuite.org/developers/service-apis/examples/obtaining-a-session.md?ask=<question>
```

The question should be specific, self-contained, and written in natural language.
The response will contain a direct answer to the question and relevant excerpts and sources from the documentation.

Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.