refactor!: unify slash handling

It is hard to remember to add `/` at the end of the URL when configuring
a new etherpad URL. Also, web server proxies tend to do weird stuff when
you assume that you have a slash on the end of each URL.

So, I took a look at how to avoid doing that. It turns out that both
urljoin / os.path.join are kinda bad for handling URL building. Also,
APPLICATION_ROOT didn't seem that necessary since Flask knows what to do
with a `/` at the start of a URL, so I dropped it.

I think this doesn't break anything!

octomode.py

@@ -1,6 +1,6 @@
 import os
 import json
-from flask import Flask, request, render_template, redirect, url_for
+from flask import Flask, request, render_template, redirect
 from urllib.request import urlopen
 from urllib.parse import urlencode
 
@@ -15,10 +15,9 @@ import pypandoc
 import markdown
 
 class Config(object):
-    APPLICATION_ROOT = '/'
     PORTNUMBER = int(os.environ.get('OCTOMODE_PORTNUMBER', 5001))
-    PAD_URL = os.environ.get('OCTOMODE_PAD_URL', 'https://pad.vvvvvvaria.org/' )
+    PAD_URL = os.environ.get('OCTOMODE_PAD_URL', 'https://pad.vvvvvvaria.org' )
-    PAD_API_URL = os.environ.get('OCTOMODE_PAD_API_URL', 'https://pad.vvvvvvaria.org/api/1.2.15/')
+    PAD_API_URL = os.environ.get('OCTOMODE_PAD_API_URL', 'https://pad.vvvvvvaria.org/api/1.2.15')
     PAD_API_KEY = os.environ.get('OCTOMODE_PAD_API_KEY', '')
 
 APP = Flask(__name__)
@@ -42,14 +41,14 @@ def get_pad_content(pad_name, ext=""):
         'apikey' : APP.config['PAD_API_KEY']
     }
     api_call = 'getText'
-    response = json.load(urlopen(f"{ APP.config['PAD_API_URL'] }{ api_call }", data=urlencode(arguments).encode()))
+    response = json.load(urlopen(f"{ APP.config['PAD_API_URL'] }/{ api_call }", data=urlencode(arguments).encode()))
 
     # create pad in case it does not yet exist
     if response['code'] == 1 and 'padID does not exist' == response['message']:
         api_call = 'createPad'
-        urlopen(f"{ APP.config['PAD_API_URL'] }{ api_call }", data=urlencode(arguments).encode())
+        urlopen(f"{ APP.config['PAD_API_URL'] }/{ api_call }", data=urlencode(arguments).encode())
         api_call = 'getText'
-        response = json.load(urlopen(f"{ APP.config['PAD_API_URL'] }{ api_call }", data=urlencode(arguments).encode()))
+        response = json.load(urlopen(f"{ APP.config['PAD_API_URL'] }/{ api_call }", data=urlencode(arguments).encode()))
 
     content = response['data']['text']
     return content
@@ -59,7 +58,7 @@ def all_pads():
         'apikey' : APP.config['PAD_API_KEY'],
     }
     api_call = 'listAllPads'
-    response = json.load(urlopen(f"{ APP.config['PAD_API_URL'] }{ api_call }", data=urlencode(arguments).encode()))
+    response = json.load(urlopen(f"{ APP.config['PAD_API_URL'] }/{ api_call }", data=urlencode(arguments).encode()))
 
     return response
 
@@ -83,7 +82,7 @@ def create_pad_on_first_run(name, ext):
             'text' : default_template
         }
         api_call = 'createPad'
-        json.load(urlopen(f"{ APP.config['PAD_API_URL'] }{ api_call }", data=urlencode(arguments).encode()))
+        json.load(urlopen(f"{ APP.config['PAD_API_URL'] }/{ api_call }", data=urlencode(arguments).encode()))
 
 def md_to_html(md_pad_content):
     # Convert Markdown to HTML
@@ -120,35 +119,33 @@ def index():
         exts = ['.md', '.css']
         for ext in exts:
             create_pad_on_first_run(name, ext)
-        return redirect(f'{ APP.config["APPLICATION_ROOT"] }{ name }/pad/')
+        return redirect(f"/{ name }/pad")
     else:
-        return render_template('start.html', application_root=APP.config["APPLICATION_ROOT"])
+        return render_template('start.html')
 
-@APP.route('/<name>/')
+@APP.route('/<name>')
 def main(name):
-    return redirect(f'{ APP.config["APPLICATION_ROOT"] }{ name }/pad/')
+    return redirect(f"/{ name }/pad")
 
-@APP.route('/<name>/pad/')
+@APP.route('/<name>/pad')
 def pad(name):
-    pad_name = f'{ name }.md'
+    url = f"{ APP.config['PAD_URL'] }/{ name }.md"
-    url = os.path.join(APP.config['PAD_URL'], pad_name)
+    return render_template('iframe.html', url=url, name=name.strip())
-    return render_template('iframe.html', url=url, name=name.strip(), application_root=APP.config["APPLICATION_ROOT"])
 
-@APP.route('/<name>/stylesheet/')
+@APP.route('/<name>/stylesheet')
 def stylesheet(name):
-    pad_name = f'{ name }.css'
+    url = f"{ APP.config['PAD_URL'] }/{ name }.css"
-    url = os.path.join(APP.config['PAD_URL'], pad_name)
+    return render_template('iframe.html', url=url, name=name.strip())
-    return render_template('iframe.html', url=url, name=name.strip(), application_root=APP.config["APPLICATION_ROOT"])
 
-@APP.route('/<name>/html/')
+@APP.route('/<name>/html')
 def html(name):
-    url = os.path.join(APP.config["APPLICATION_ROOT"], name, 'preview.html')
+    url = f"/{ name }/preview.html"
-    return render_template('iframe.html', url=url, name=name.strip(), application_root=APP.config["APPLICATION_ROOT"])
+    return render_template('iframe.html', url=url, name=name.strip())
 
-@APP.route('/<name>/pdf/')
+@APP.route('/<name>/pdf')
 def pdf(name):
-    url = os.path.join(APP.config["APPLICATION_ROOT"], name, 'pagedjs.html')
+    url = f"/{name}/pagedjs.html"
-    return render_template('pdf.html', url=url, name=name.strip(), application_root=APP.config["APPLICATION_ROOT"])
+    return render_template('pdf.html', url=url, name=name.strip())
 
 # //////////////////
 # RENDERED RESOURCES 
@@ -175,7 +172,7 @@ def preview(name):
         lang = "en"
         title = "No title"
 
-    return render_template('preview.html', name=name.strip(), pad_content=html, lang=lang, title=title, application_root=APP.config["APPLICATION_ROOT"])
+    return render_template('preview.html', name=name.strip(), pad_content=html, lang=lang, title=title)
 
 @APP.route('/<name>/pagedjs.html')
 def pagedjs(name):
@@ -186,10 +183,10 @@ def pagedjs(name):
     lang = metadata['language'][0]
     title = metadata['title'][0]
 
-    return render_template('pagedjs.html', name=name.strip(), pad_content=html, lang=lang, title=title, application_root=APP.config["APPLICATION_ROOT"])
+    return render_template('pagedjs.html', name=name.strip(), pad_content=html, lang=lang, title=title)
 
 # //////////////////
 
 if __name__ == '__main__':
     APP.debug=True
-    APP.run(host="0.0.0.0", port=f'{ APP.config["PORTNUMBER"] }', threaded=True)
+    APP.run(host="0.0.0.0", port=APP.config["PORTNUMBER"], threaded=True)

templates/base.html

@@ -3,7 +3,7 @@
 <head>
 	<meta charset="utf-8" />
 	<title>{{ name }} in octomode</title>
-	<link rel="stylesheet" type="text/css" href="{{ application_root }}static/main.css">
+  <link rel="stylesheet" type="text/css" href="{{ url_for('static', filename='main.css') }}">
 	{% block head %}
 	{% endblock %}
 </head>
@@ -18,17 +18,21 @@ window.addEventListener('load', function () {
 
 	// Insert the nav buttons, after the page is loaded
 	const nav = document.createElement('div');
-		  nav.id = 'nav';
+	nav.id = 'nav';
-	const name = '{{ name }}';
-	const application_root = '{{ application_root }}';
 
 	nav.innerHTML = `
-		<h1>${ name } <a href="${ application_root }"><em class="octomode">in octomode</em></a></h1>
+    <h1>{{ name }} <a href="/"><em class="octomode">in octomode</em></a></h1>
 		<div id="buttons">
-			<a href="${ application_root }${ name }/pad/"><button>pad</button></a>: <input type="text" name="pad" value="https://pad.vvvvvvaria.org/${ name }.md">
+
-			<a href="${ application_root }${ name }/stylesheet/"><button>stylesheet</button></a>: <input type="text" name="pad" value="https://pad.vvvvvvaria.org/${ name }.css">
+      <a href="/{{ name }}/pad"><button>pad</button></a>:
-			<a href="${ application_root }${ name }/html/"><button>html</button></a>
+      <input type="text" name="pad" value="https://pad.vvvvvvaria.org/{{ name }}.md">
-			<a href="${ application_root }${ name }/pdf/"><button>pdf</button></a>
+
+      <a href="/{{ name }}/stylesheet"><button>stylesheet</button></a>:
+      <input type="text" name="pad" value="https://pad.vvvvvvaria.org/{{ name }}.css">
+
+      <a href="/{{ name }}/html"><button>html</button></a>
+
+      <a href="/{{ name }}/pdf"><button>pdf</button></a>
 		</div>`;
 
 	document.body.insertBefore(nav, document.body.firstChild);

templates/pagedjs.html

@@ -3,9 +3,9 @@
 <head>
     <meta charset="utf-8">
     <meta name="viewport" content="width=device-width, initial-scale=1.0">
-    <script src="{{ application_root }}static/paged.polyfill.js" type="text/javascript"></script>
+    <script src="{{ url_for('static', filename='paged.polyfill.js') }}" type="text/javascript"></script>
-    <link href="{{ application_root }}static/pagedjs.css" rel="stylesheet" type="text/css" media="screen">
+    <link href="{{ url_for('static', filename='pagedjs.css') }}" rel="stylesheet" type="text/css" media="screen">
-    <link href="{{ application_root }}{{ name }}/stylesheet.css" rel="stylesheet" type="text/css" media="print">
+    <link href="/{{ name }}/stylesheet.css" rel="stylesheet" type="text/css" media="print">
     <title>{{ title }}</title>
 </head>
 <body>

templates/pdf.html

@@ -16,7 +16,7 @@ window.addEventListener('load', function () {
       // Load the main.css again, to load the stylesheet for the nav
       var cssLink = document.createElement('link');
       cssLink.rel = 'stylesheet';
-      cssLink.href = '{{ application_root }}/static/main.css';
+      cssLink.href = '{{ url_for("static", filename="main.css") }}';
       var head = document.getElementsByTagName('head')[0];
       head.insertBefore(cssLink, head.firstChild);
 

templates/preview.html

@@ -3,7 +3,7 @@
 <head>
     <meta charset="utf-8">
     <meta name="viewport" content="width=device-width, initial-scale=1.0">
-    <link href="{{ application_root }}/{{ name }}/stylesheet.css" rel="stylesheet" type="text/css" media="screen">
+    <link href="{{ name }}/stylesheet.css" rel="stylesheet" type="text/css" media="screen">
     <title>{{ title }}</title>
 </head>
 <body>

templates/start.html

@@ -3,10 +3,10 @@
 <head>
 	<meta charset="utf-8" />
 	<title>octomode</title>
-	<link rel="stylesheet" type="text/css" href="{{ application_root }}static/main.css">
+  <link rel="stylesheet" type="text/css" href="{{ url_for('static', filename='main.css') }}">
 </head>
 <body class="start-page">
-	<form action="{{ application_root }}" method="POST">
+	<form action="/" method="POST">
 		<h1><input type="submit" value="open"> <input type="text" name="name"> <em class="octomode">in octomode</em></h1>
 	</form>
 </body>