Authentication

The authentication is based upon the OAuth 2.0 client credentials flow.

You'll need your registered OAuth 2.0 application's client_id and client_secret.

Then you can get an access token by sending a request to POST /o/token/. This gives you an access token, which is valid for 1 hour.

Example (cURL)

curl -u '<client_id>:<client_secret>' \
     -X POST -H "Content-Type: application/x-www-form-urlencoded" \
     "https://demo.openesg.de/o/token/" \
     -d "grant_type=client_credentials"

Example response:

{
    "access_token": "sbKAFfq1btNSorhZBLBxmuaoArrBrY",
    "expires_in": 3600,
    "token_type": "Bearer",
    "scope": "read write"
}

Example (Python)

from oauthlib.oauth2 import BackendApplicationClient
from requests.auth import HTTPBasicAuth
from requests_oauthlib import OAuth2Session

API_BASE = "https://demo.openesg.de"

client = BackendApplicationClient(client_id=env("CLIENT_ID"))
session = OAuth2Session(client=client)

auth = HTTPBasicAuth(env("CLIENT_ID"), env("CLIENT_SECRET"))
token = session.fetch_token(token_url=f"{API_BASE}/o/token/", auth=auth)

Example (Postman)

Create a new Postman Collection by importing the downloaded Open API 3.1 schema JSON file. Then add the following Pre-request Script in the root of the Collection:

const tokenUrl = 'https://demo.openesg.de/o/token/';

const clientId = '<client-id>';
const clientSecret = '<client-secret>';

const getTokenRequest = {
  method: 'POST',
  url: tokenUrl,
  body: {
      mode: 'formdata',
      formdata: [
          { key: 'grant_type', value: 'client_credentials' },
          { key: 'client_id', value: clientId },
          { key: 'client_secret', value: clientSecret }
      ]
  }
};

pm.sendRequest(getTokenRequest, (err, response) => {
  const jsonResponse = response.json();
  const newAccessToken = jsonResponse.access_token;

  pm.variables.set('access_token', newAccessToken);
});

Now in the Authorization tab, set

• Type to Bearer Token and
• Token to {{access_token}}

All Endpoints should then use the authorization type Inherit auth from parent.