Add v2 API endpoint to fetch the openAPI spec (#2554)

* Add v2 API endpoint to fetch the openAPI spec

- Supports EN and FR versions of the spec by passing in the lang query
  param

* Split and rename endpoints

* The endpoints are now `/v2/openapi-{en|fr}` instead of using a query
  string
* The spec endpoint no longer requires auth

* Make route paths consistent

Author: whabanks

app/__init__.py

@@ -286,7 +286,8 @@ def register_blueprint(application):
 
 
 def register_v2_blueprints(application):
-    from app.authentication.auth import requires_auth
+    from app.authentication.auth import requires_auth, requires_no_auth
+    from app.v2.api_spec.get_api_spec import v2_api_spec_blueprint
     from app.v2.inbound_sms.get_inbound_sms import (
         v2_inbound_sms_blueprint as get_inbound_sms,
     )
@@ -310,6 +311,8 @@ def register_v2_blueprints(application):
 
     register_notify_blueprint(application, get_inbound_sms, requires_auth)
 
+    register_notify_blueprint(application, v2_api_spec_blueprint, requires_no_auth)
+
 
 def init_app(app):
     @app.before_request

app/v2/api_spec/__init__.py

@@ -0,0 +1,27 @@
+import os
+
+from flask import Blueprint, current_app, send_file
+
+v2_api_spec_blueprint = Blueprint("v2_api_spec", __name__, url_prefix="/v2")
+
+
+@v2_api_spec_blueprint.route("/openapi-en", methods=["GET"])
+def get_v2_api_spec_en():
+    """
+    Returns the English OpenAPI specification for the v2 Notifications API.
+    """
+    spec_path = os.path.join(current_app.root_path, "openapi/v2-notifications-api-en.yaml")
+    spec_path = os.path.abspath(spec_path)
+
+    return send_file(spec_path, mimetype="application/yaml", as_attachment=False, download_name="v2-notifications-api.yaml")
+
+
+@v2_api_spec_blueprint.route("/openapi-fr", methods=["GET"])
+def get_v2_api_spec_fr():
+    """
+    Returns the French OpenAPI specification for the v2 Notifications API.
+    """
+    spec_path = os.path.join(current_app.root_path, "openapi/v2-notifications-api-fr.yaml")
+    spec_path = os.path.abspath(spec_path)
+
+    return send_file(spec_path, mimetype="application/yaml", as_attachment=False, download_name="v2-notifications-api.yaml")