unify redis config (closes #8)

also, not sure why brotli was being initialised in routes not in app

app.py

@@ -9,18 +9,18 @@ from flask_limiter import Limiter
 from lib.auth import get_viewer
 import os
 import mimetypes
+import lib.brotli
 
 app = Flask(__name__)
 
 default_config = {
         "SQLALCHEMY_TRACK_MODIFICATIONS": False,
         "SQLALCHEMY_DATABASE_URI": "postgresql+psycopg2:///forget",
-        "CELERY_BROKER": "redis://",
         "HTTPS": True,
         "SENTRY_CONFIG": {},
-        "RATELIMIT_STORAGE_URL": "redis://",
         "REPO_URL": "https://github.com/codl/forget",
         "COMMIT_URL": "https://github.com/codl/forget/commits/{hash}",
+        "REDIS_URI": "redis://",
 }
 
 app.config.update(default_config)
@@ -38,6 +38,17 @@ metadata = MetaData(naming_convention={
 db = SQLAlchemy(app, metadata=metadata)
 migrate = Migrate(app, db)
 
+if not 'RATELIMIT_STORAGE_URL' in app.config:
+    uri = app.config['REDIS_URI']
+    assert not uri.startswith('unix://'), "flask-limiter does not support redis over a unix socket"
+    app.config['RATELIMIT_STORAGE_URL'] = uri
+
+if not 'CELERY_BROKER' in app.config:
+    uri = app.config['REDIS_URI']
+    if uri.startswith('unix://'):
+        uri = url.replace('unix', 'redis+socket', 1)
+    app.config['CELERY_BROKER'] = uri
+
 sentry = None
 if 'SENTRY_DSN' in app.config:
     from raven.contrib.flask import Sentry
@@ -100,3 +111,5 @@ def install_security_headers(resp):
 
 
 mimetypes.add_type('image/webp', '.webp')
+
+lib.brotli.brotli(app)

config.example.py

@@ -13,6 +13,14 @@ only postgresql with psycopg2 driver is officially supported
 """
 # SQLALCHEMY_DATABASE_URI='postgresql+psycopg2:///forget'
 
+"""
+REDIS URI
+
+see https://redis-py.readthedocs.io/en/latest/#redis.ConnectionPool.from_url
+for syntax reference
+"""
+# REDIS_URI='redis://'
+
 """
 TWITTER CREDENTIALS
 
@@ -27,32 +35,11 @@ this will be necessary so we can tell twitter where to redirect
 """
 # SERVER_NAME="localhost:5000"
 
-# CELERY_BROKER='redis://'
 
 # HTTPS=True
 
 # SENTRY_DSN='https://foo:bar@sentry.io/69420'
 
-'''
-you can set this to memory:// if you only have one web process
-or if you don't care about people exhausting your twitter api
-key and your celery workers by making hundreds of login
-requests and uploading hundreds of bogus tweet archives
-
-docs here <https://flask-limiter.readthedocs.io/en/stable/#configuration>
-'''
-# RATELIMIT_STORAGE_URL='redis://'
-
-# REDIS=dict(
-#        db=0
-#
-#        host='localhost'
-#        port=6379
-#        # or...
-#        unix_socket_path='/var/run/redis/redis.sock'
-#        # see `pydoc redis.StrictRedis.__init__` for full list of arguments
-#     )
-
 """
 you can also use any config variable that flask expects here, such as
 """

lib/brotli.py

@@ -8,10 +8,8 @@ import mimetypes
 
 
 class BrotliCache(object):
-    def __init__(self, redis_kwargs=None, max_wait=0.020, expire=60*60*6):
-        if not redis_kwargs:
-            redis_kwargs = {}
-        self.redis = redis.StrictRedis(**redis_kwargs)
+    def __init__(self, redis_uri='redis://', max_wait=0.020, expire=60*60*6):
+        self.redis = redis.StrictRedis.from_url(redis_uri)
         self.max_wait = max_wait
         self.expire = expire
         self.redis.client_setname('brotlicache')
@@ -81,5 +79,5 @@ def brotli(app, static=True, dynamic=True):
     if static:
         app.view_functions['static'] = static_maybe_gzip_brotli
     if dynamic:
-        cache = BrotliCache()
+        cache = BrotliCache(redis_uri = app.config.get('REDIS_URI'))
         app.after_request(cache.wrap_response)

routes.py

@@ -14,7 +14,6 @@ from twitter import TwitterError
 from urllib.error import URLError
 import version
 import lib.version
-import lib.brotli
 import lib.settings
 import lib.json
 
@@ -54,9 +53,6 @@ def touch_viewer(resp):
     return resp
 
 
-lib.brotli.brotli(app)
-
-
 @app.route('/')
 def index():
     if g.viewer: