Fetch releases.yml to assert if Source is valid

src/risotto/services/source/source.py

@@ -2,6 +2,11 @@ from typing import Dict, List
 from ...controller import Controller
 from ...register import register
 from ...context import Context
+import requests
+import yaml
+import os
+from ...utils import _
+from ...config import get_config
 
 
 class Risotto(Controller):
@@ -14,6 +19,23 @@ class Risotto(Controller):
         ON CONFLICT (SourceName) DO UPDATE SET SourceURL = $2
         RETURNING SourceId
         """
+        # If given url is not 'none' (a.k.a internal source)
+        # Look for file releases.yml at given url
+        # If such a file exists, consider source a valid one and create source in database.
+        if source_url != 'none':
+            try:
+                releases = yaml.load(requests.get(source_url.rstrip('/') + '/releases.yml').content, Loader=yaml.SafeLoader)
+            except requests.exceptions.ConnectionError as err:
+                raise Exception(_('Invalid URL'))
+            except yaml.scanner.ScannerError as err:
+                raise Exception(_('Invalid releases.yml file'))
+            except:
+                raise Exception(_('Invalid source'))
+        else:
+            releases = {'1.0.0': {'distribution': 'stable'}}
+        os.makedirs(os.path.join(get_config().get('source').get('root_path'), source_name))
+        with open(os.path.join(get_config().get('source').get('root_path'), source_name, 'releases.yml')) as release_file:
+            yaml.dump(releases, release_file)
         source_id = await risotto_context.connection.fetchval(source_upsert,
                                                               source_name,
                                                               source_url)