Apply proxy fix for https scheme

sets the wsgi.url_scheme from X-Forwarded-Proto header

snip/__init__.py

@@ -1,5 +1,6 @@
 import os
 from flask import Flask
+from werkzeug.middleware.proxy_fix import ProxyFix
 
 
 ###########################
@@ -28,6 +29,8 @@ app.config.update(
     SQLALCHEMY_DATABASE_URI        = snip_config.SNIP_DATABASE_URI,
     SQLALCHEMY_TRACK_MODIFICATIONS = snip_config.SNIP_DATABASE_TRACK_MODIFICATION)
 
+if snip_config.SNIP_FLASK_PROXYFIX:
+    app = ProxyFix(app)
 
 ###################
 # Setup SQAlchemy #

snip/config.py

@@ -47,6 +47,7 @@ class SnipConfig(BaseModel):
     # Non-standard flask settings
     SNIP_FLASK_HOST: str = "localhost"
     SNIP_FLASK_PORT: int = 5000
+    SNIP_FLASK_PROXYFIX: bool = False
 
     # Snip settings
     SNIP_STAGE: Optional[str]

snip/views.py

@@ -1,4 +1,4 @@
-from flask import render_template, redirect, session, request
+from flask import render_template, redirect, request
 from werkzeug import exceptions
 
 from . import app