Environment variables for default port and bind address (#342)

* Add env vars to override default bind address and port

* Update main.py

Prefix bind address and port with SNAPPASS_

* Update README.rst

update readme to prefix SNAPPASS_ to bind address and port

---------

Co-authored-by: Yuru Shao <[email protected]>

README.rst

@@ -96,6 +96,10 @@ need to change this.
 
 ``HOST_OVERRIDE``: (optional) Used to override the base URL if the app is unaware. Useful when running behind reverse proxies like an identity-aware SSO. Example: ``sub.domain.com``
 
+``SNAPPASS_BIND_ADDRESS``: (optional) Used to override the default bind address of 0.0.0.0 for flask app Example: ``127.0.0.1``
+
+``SNAPPASS_PORT``: (optional) Used to override the default port of 5000 Example: ``6000``
+
 APIs
 ----
 

snappass/main.py

@@ -353,7 +353,8 @@ def health_check():
 
 @check_redis_alive
 def main():
-    app.run(host='0.0.0.0')
+    app.run(host=os.environ.get('SNAPPASS_BIND_ADDRESS', '0.0.0.0'),
+            port=os.environ.get('SNAPPASS_PORT', 5000))
 
 
 if __name__ == '__main__':