Implement script to post-process OpenAPI generated schema

The script can be used to:
- Expand aliases and anchors
- Set API version
- Set server URL
- Enable API key authentication scheme

Signed-off-by: Vasilis Tsiligiannis <acinonyx@openwrt.gr>

.gitlab-ci.yml

@@ -43,23 +43,16 @@ schema:
   image: ${GITLAB_CI_IMAGE_PYTHON}
   script:
     - pip install --no-cache-dir --no-deps -r "requirements.txt" --force-reinstall .
-    - |
-      ./manage.py generateschema | python -c "
-      # XXX: Workaround for https://github.com/encode/django-rest-framework/issues/7479
-      # XXX: Remove after upgrade to DRF 3.12
-      import yaml
-      import sys
-      class Dumper(yaml.Dumper):
-          def ignore_aliases(self, data):
-              return True
-      sys.stdout.buffer.write(
-          yaml.dump(
-              yaml.safe_load(sys.stdin),
-              default_flow_style=False,
-              sort_keys=False, Dumper=Dumper
-          ).encode('utf-8')
-      )
-      "  > satnogs-db-api-client/api-schema.yml
+    - >-
+      ./manage.py generateschema
+      --title "SatNOGS DB"
+      --description "SatNOGS DB is a transmitter suggestions and crowd-sourcing app." |
+      ./contrib/postprocess-openapi-schema.py
+      --expand-aliases
+      --api-version '1'
+      --server-url 'https://db.satnogs.org'
+      --enable-apikey-auth -
+      > satnogs-db-api-client/api-schema.yml
   artifacts:
     expire_in: 1 week
     when: always

contrib/postprocess-openapi-schema.py

@@ -0,0 +1,79 @@
+#!/usr/bin/env python
+#
+# Script to postprocess OpenAPI generated schema
+#
+# Copyright (C) 2020 Libre Space Foundation <https://libre.space/>
+#
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+import argparse
+import sys
+
+import yaml
+
+
+class Dumper(yaml.Dumper):
+    def ignore_aliases(self, data):
+        return True
+
+
+parser = argparse.ArgumentParser(description="Postprocess OpenAPI generated schema")
+parser.add_argument('--api-version', type=str, help='Set API version')
+parser.add_argument('--server-url', type=str, help='Set API server base URL')
+parser.add_argument('--expand-aliases', action='store_true', help='Expand anchors and aliases')
+parser.add_argument(
+    '--enable-apikey-auth', action='store_true', help='Enable DRF API key authentication'
+)
+parser.add_argument(
+    'input_file',
+    type=argparse.FileType('r', encoding='UTF-8'),
+    help='OpenAPI schema file or \'-\' for stdin'
+)
+args = parser.parse_args()
+
+schema = yaml.safe_load(args.input_file)
+if args.api_version is not None:
+    schema['info']['version'] = args.api_version
+
+if args.server_url is not None:
+    schema['servers'] = [{'url': args.server_url}]
+
+if args.enable_apikey_auth:
+    schema.update(
+        {
+            'components': {
+                'securitySchemes': {
+                    'ApiKeyAuth': {
+                        'type': 'apiKey',
+                        'in': 'header',
+                        'name': 'Authorization'
+                    }
+                }
+            },
+            'security': [
+                {
+                    'ApiKeyAuth': []
+                },
+            ]
+        }
+    )
+
+if args.expand_aliases:
+    schema_dump = yaml.dump(
+        schema, default_flow_style=False, sort_keys=False, Dumper=Dumper
+    ).encode('utf-8')
+else:
+    schema_dump = yaml.dump(schema, default_flow_style=False, sort_keys=False).encode('utf-8')
+
+sys.stdout.buffer.write(schema_dump)