Merge pull request #129 from jezdez/redis-improvements

Remove accidental lockfile ImportError message when using RedisCache

Author: ionrock

cachecontrol/caches/__init__.py

@@ -1,18 +1,2 @@
-from textwrap import dedent
-
-try:
-    from .file_cache import FileCache  # noqa
-except ImportError:
-    notice = dedent('''
-    NOTE: In order to use the FileCache you must have
-    lockfile installed. You can install it via pip:
-      pip install lockfile
-    ''')
-    print(notice)
-
-
-try:
-    import redis  # noqa
-    from .redis_cache import RedisCache  # noqa
-except ImportError:
-    pass
+from .file_cache import FileCache  # noqa
+from .redis_cache import RedisCache  # noqa

cachecontrol/caches/file_cache.py

@@ -1,8 +1,6 @@
 import hashlib
 import os
-
-from lockfile import LockFile
-from lockfile.mkdirlockfile import MkdirLockFile
+from textwrap import dedent
 
 from ..cache import BaseCache
 from ..controller import CacheController
@@ -55,19 +53,29 @@ def __init__(self, directory, forever=False, filemode=0o0600,
         if use_dir_lock is not None and lock_class is not None:
             raise ValueError("Cannot use use_dir_lock and lock_class together")
 
-        if use_dir_lock:
-            lock_class = MkdirLockFile
-
-        if lock_class is None:
-            lock_class = LockFile
+        try:
+            from lockfile import LockFile
+            from lockfile.mkdirlockfile import MkdirLockFile
+        except ImportError:
+            notice = dedent("""
+            NOTE: In order to use the FileCache you must have
+            lockfile installed. You can install it via pip:
+              pip install lockfile
+            """)
+            raise ImportError(notice)
+        else:
+            if use_dir_lock:
+                lock_class = MkdirLockFile
+
+            elif lock_class is None:
+                lock_class = LockFile
 
         self.directory = directory
         self.forever = forever
         self.filemode = filemode
         self.dirmode = dirmode
         self.lock_class = lock_class
 
-
     @staticmethod
     def encode(x):
         return hashlib.sha224(x.encode()).hexdigest()

docs/storage.rst

@@ -69,7 +69,14 @@ RedisCache
 
 The `RedisCache` uses a Redis database to store values. The values are
 stored as strings in redis, which means the get, set and delete
-actions are used.
+actions are used. It requires the `redis`_ library to be installed.
+
+.. note::
+
+  Note that you can install this dependency automatically with pip
+  by requesting the *redis* extra: ::
+
+    pip install cachecontrol[redis]
 
 The `RedisCache` also provides a clear method to delete all keys in a
 database. Obviously, this should be used with caution as it is naive
@@ -94,3 +101,4 @@ a better method for utilizing redis as a cache.
 .. _httplib2: http://code.google.com/p/httplib2/
 .. _lockfile: https://github.com/smontanaro/pylockfile
 .. _requests 2.1: http://docs.python-requests.org/en/latest/community/updates/#id2
+.. _redis: https://github.com/andymccurdy/redis-py

setup.py

@@ -22,6 +22,7 @@
     ],
     extras_require={
         'filecache': ['lockfile>=0.9'],
+        'redis': ['redis>=2.10.5'],
     },
     entry_points={
         'console_scripts': [

tests/test_regressions.py

@@ -3,7 +3,7 @@
 
 
 from cachecontrol import CacheControl
-from cachecontrol.caches.file_cache import FileCache
+from cachecontrol.caches import FileCache
 from cachecontrol.filewrapper import CallbackFileWrapper
 from requests import Session