Added config option to address instance behind reverse proxy

Config options now allow setting a "root url", which defaults to the
request url root. Saving a new url in this field will allow for proper
redirects and usage of the opensearch element.

Also provides a possible solution for #17, where the default flask redirect method redirects to
http instead of https.

app/routes.py

@@ -19,12 +19,17 @@ CONFIG_PATH = app.config['STATIC_FOLDER'] + '/config.json'
 @app.before_request
 def before_request_func():
     g.user_request = Request(request.headers.get('User-Agent'))
-    g.user_config = json.load(open(CONFIG_PATH)) if os.path.exists(CONFIG_PATH) else {}
+    g.user_config = json.load(open(CONFIG_PATH)) if os.path.exists(CONFIG_PATH) else {'url': request.url_root}
+
+    if 'url' not in g.user_config or not g.user_config['url']:
+        g.user_config['url'] = request.url_root
+
+    g.app_location = g.user_config['url']
 
 
 @app.errorhandler(404)
 def unknown_page(e):
-    return redirect('/')
+    return redirect(g.app_location)
 
 
 @app.route('/', methods=['GET'])
@@ -35,11 +40,11 @@ def index():
 
 @app.route('/opensearch.xml', methods=['GET'])
 def opensearch():
-    url_root = request.url_root
-    if url_root.endswith('/'):
-        url_root = url_root[:-1]
+    opensearch_url = g.app_location
+    if opensearch_url.endswith('/'):
+        opensearch_url = opensearch_url[:-1]
 
-    template = render_template('opensearch.xml', main_url=url_root)
+    template = render_template('opensearch.xml', main_url=opensearch_url)
     response = make_response(template)
     response.headers['Content-Type'] = 'application/xml'
     return response
@@ -78,11 +83,14 @@ def config():
         return json.dumps(g.user_config)
     else:
         config_data = request.form.to_dict()
+        if 'url' not in config_data or not config_data['url']:
+            config_data['url'] = request.url_root
+
         with open(app.config['STATIC_FOLDER'] + '/config.json', 'w') as config_file:
             config_file.write(json.dumps(config_data, indent=4))
             config_file.close()
 
-        return redirect('/')
+        return redirect(config_data['url'])
 
 
 @app.route('/url', methods=['GET'])

app/static/css/main.css

@@ -113,3 +113,7 @@ button::-moz-focus-inner {
     -webkit-box-decoration-break: clone;
     box-decoration-break: clone;
 }
+
+.hidden {
+    display: none;
+}

app/static/js/controller.js

@@ -15,7 +15,7 @@ const setupSearchLayout = () => {
     });
 }
 
-const fillConfigValues = (near, nojs, dark) => {
+const fillConfigValues = (near, nojs, dark, url) => {
     // Request existing config info
     let xhrGET = new XMLHttpRequest();
     xhrGET.open("GET", "/config");
@@ -29,19 +29,11 @@ const fillConfigValues = (near, nojs, dark) => {
         let configSettings = JSON.parse(xhrGET.responseText);
 
         near.value = configSettings["near"] ? configSettings["near"] : "";
-        near.addEventListener("keyup", function() {
-            configSettings["near"] = near.value;
-        });
-
         nojs.checked = !!configSettings["nojs"];
-        nojs.addEventListener("change", function() {
-           configSettings["nojs"] = nojs.checked ? 1 : 0;
-        });
-
         dark.checked = !!configSettings["dark"];
-        dark.addEventListener("change", function() {
-           configSettings["dark"] = dark.checked ? 1 : 0;
-        });
+
+        // Addresses the issue of incorrect URL being used behind reverse proxy
+        url.value = configSettings["url"] ? configSettings["url"] : "";
     };
 
     xhrGET.send();
@@ -65,8 +57,9 @@ const setupConfigLayout = () => {
     const near = document.getElementById("config-near");
     const noJS = document.getElementById("config-nojs");
     const dark = document.getElementById("config-dark");
+    const url  = document.getElementById("config-url");
 
-    fillConfigValues(near, noJS, dark);
+    fillConfigValues(near, noJS, dark, url);
 }
 
 document.addEventListener("DOMContentLoaded", function() {

app/templates/index.html

@@ -53,6 +53,10 @@
                             <label for="config-dark">Dark Mode: </label>
                             <input type="checkbox" name="dark" id="config-dark">
                         </div>
+                        <div class="config-div">
+                            <label for="config-url">Root URL: </label>
+                            <input type="text" name="url" id="config-url" value="">
+                        </div>
                         <div class="config-div">
                             <input type="submit" id="config-submit" value="Save">
                         </div>