Authenticate to Hello Asso by client id and secret

apps/participation/management/commands/check_hello_asso.py

@@ -10,6 +10,17 @@ import requests
 
 class Command(BaseCommand):
     def handle(self, *args, **options):  # noqa: C901
+        # Get access token
+        response = requests.post('https://api.helloasso.com/oauth2/token', headers={
+            'Content-Type': 'application/x-www-form-urlencoded',
+        }, data={
+            'client_id': os.getenv('HELLOASSO_CLIENT_ID', ''),
+            'client_secret': os.getenv('HELLOASSO_CLIENT_SECRET', ''),
+            'grant_type': 'client_credentials',
+        }).json()
+
+        token = response['access_token']
+
         organization = "animath"
         form_slug = "tfjm-2021"
         from_date = "2000-01-01"
@@ -17,7 +28,7 @@ class Command(BaseCommand):
               f"?from={from_date}&pageIndex=1&pageSize=10000&retrieveOfflineDonations=false"
         headers = {
             "Accept": "application/json",
-            "Authorization": f"Bearer {os.getenv('HELLO_ASSO_TOKEN', '')}",
+            "Authorization": f"Bearer {token}",
         }
         http_response = requests.get(url, headers=headers)
         response = http_response.json()