From f48671d9bbf4361c46eda455ae705d9306beaa50 Mon Sep 17 00:00:00 2001
From: Andrei Zbikowski <b1naryth1ef@users.noreply.github.com>
Date: Sat, 17 Jun 2017 01:15:49 -0700
Subject: [PATCH] Add support for built-in HTTP/Flask server (#34)

* Add support for built-in HTTP/Flask server

* Don't default http_enabled to true
---
 disco/bot/bot.py         | 20 ++++++++++++++++++++
 disco/bot/plugin.py      | 14 ++++++++++++++
 docs/installation.md     |  1 +
 examples/basic_plugin.py |  5 +++++
 setup.py                 |  1 +
 5 files changed, 41 insertions(+)

diff --git a/disco/bot/bot.py b/disco/bot/bot.py
index 3388b90..00d1e6d 100644
--- a/disco/bot/bot.py
+++ b/disco/bot/bot.py
@@ -1,11 +1,13 @@
 import re
 import os
 import six
+import gevent
 import inspect
 import importlib
 
 from six.moves import reload_module
 from holster.threadlocal import ThreadLocal
+from gevent.wsgi import WSGIServer
 
 from disco.types.guild import GuildMember
 from disco.bot.plugin import Plugin
@@ -63,6 +65,13 @@ class BotConfig(Config):
         The serialization format plugin configuration files are in.
     plugin_config_dir : str
         The directory plugin configuration is located within.
+    http_enabled : bool
+        Whether to enable the built-in Flask server which allows plugins to handle
+        and route HTTP requests.
+    http_host : str
+        The host string for the HTTP Flask server (if enabled)
+    http_port : int
+        The port for the HTTP Flask server (if enabled)
     """
     levels = {}
     plugins = []
@@ -90,6 +99,10 @@ class BotConfig(Config):
     storage_serializer = 'json'
     storage_path = 'storage.json'
 
+    http_enabled = False
+    http_host = '0.0.0.0'
+    http_port = 7575
+
 
 class Bot(LoggingClass):
     """
@@ -132,6 +145,13 @@ class Bot(LoggingClass):
         if self.client.config.manhole_enable:
             self.client.manhole_locals['bot'] = self
 
+        if self.config.http_enabled:
+            from flask import Flask
+            self.log.info('Starting HTTP server bound to %s:%s', self.config.http_host, self.config.http_port)
+            self.http = Flask('disco')
+            self.http_server = WSGIServer((self.config.http_host, self.config.http_port), self.http)
+            self.http_server_greenlet = gevent.spawn(self.http_server.serve_forever)
+
         self.plugins = {}
         self.group_abbrev = {}
 
diff --git a/disco/bot/plugin.py b/disco/bot/plugin.py
index 155e581..da719a4 100644
--- a/disco/bot/plugin.py
+++ b/disco/bot/plugin.py
@@ -131,6 +131,17 @@ class BasePluginDeco(object):
             'kwargs': kwargs,
         })
 
+    @classmethod
+    def route(cls, *args, **kwargs):
+        """
+        Adds an HTTP route.
+        """
+        return cls.add_meta_deco({
+            'type': 'http.add_route',
+            'args': args,
+            'kwargs': kwargs,
+        })
+
 
 class PluginDeco(BasePluginDeco):
     """
@@ -227,6 +238,9 @@ class Plugin(LoggingClass, PluginDeco):
                     getattr(command.parser, meta['type'].split('.', 1)[-1])(
                         *meta['args'],
                         **meta['kwargs'])
+        elif meta['type'] == 'http.add_route':
+            meta['kwargs']['view_func'] = member
+            self.bot.http.add_url_rule(*meta['args'], **meta['kwargs'])
         else:
             raise Exception('unhandled meta type {}'.format(meta))
 
diff --git a/docs/installation.md b/docs/installation.md
index 70de528..778d8c8 100644
--- a/docs/installation.md
+++ b/docs/installation.md
@@ -21,6 +21,7 @@ pip install disco[performance]
 | Name | Explanation | Versions |
 |------|-------------|----------|
 | voice | Adds functionality required to connect and use voice | Both |
+| http | Adds a built-in HTTP server w/ Flask, allowing plugins to handle HTTP requests | Both |
 | music | Adds the ability to stream and play music from various third party sites | Both |
 | performance | Adds a faster JSON parser (ujson) and an ETF encoding parser | 2.x Only |
 | sharding | Adds a library which is required to enable auto-sharding | 2.x Only |
diff --git a/examples/basic_plugin.py b/examples/basic_plugin.py
index c57866c..a55f352 100644
--- a/examples/basic_plugin.py
+++ b/examples/basic_plugin.py
@@ -74,3 +74,8 @@ class BasicPlugin(Plugin):
         if args.help:
             return event.msg.reply(event.parser.format_help())
         event.msg.reply(args.asdf)
+
+    @Plugin.route('/test')
+    def on_test_route(self):
+        print 'WOW!'
+        return 'Hi!'
diff --git a/setup.py b/setup.py
index 0fb1232..7f4488b 100644
--- a/setup.py
+++ b/setup.py
@@ -18,6 +18,7 @@ with open('README.md') as f:
 
 extras_require = {
     'voice': ['pynacl==1.1.2'],
+    'http': ['flask==0.12.2'],
     'music': ['youtube_dl==2017.4.26'],
     'performance': ['erlpack==0.3.2', 'ujson==1.35'],
     'sharding': ['gipc==0.6.0'],