remote: print which dependencies we are missing

Signed-off-by: Ruslan Kuprieiev <[email protected]>

dvc/remote/base.py

@@ -33,17 +33,20 @@ class DataCloudError(DvcException):
 
 class RemoteBase(object):
     REGEX = None
-    REQUIRES = []
+    REQUIRES = {}
 
     def __init__(self, project, config):
         pass
 
     @classmethod
     def supported(cls, config):
-        url_ok = cls.match(config[Config.SECTION_REMOTE_URL])
-        deps_ok = all(cls.REQUIRES)
+        url = config[Config.SECTION_REMOTE_URL]
+        url_ok = cls.match(url)
+        deps_ok = all(cls.REQUIRES.values())
         if url_ok and not deps_ok:
-            Logger.warning("URL matches but requires missing dependencies")
+            missing = [k for k,v in cls.REQUIRES.items() if v == None]
+            msg = "URL \'{}\' is supported but requires these missing dependencies: {}"
+            Logger.warn(msg.format(url, str(missing)))
         return url_ok and deps_ok
 
     @classmethod

dvc/remote/gs.py

@@ -20,7 +20,7 @@ from dvc.progress import progress
 class RemoteGS(RemoteBase):
     scheme = 'gs'
     REGEX = r'^gs://(?P<path>.*)$'
-    REQUIRES = RemoteBase.REQUIRES + [storage]
+    REQUIRES = {'google.cloud.storage': storage}
     PARAM_ETAG = 'etag'
 
     def __init__(self, project, config):

dvc/remote/s3.py

@@ -35,7 +35,7 @@ class Callback(object):
 class RemoteS3(RemoteBase):
     scheme = 's3'
     REGEX = r'^s3://(?P<path>.*)$'
-    REQUIRES = RemoteBase.REQUIRES + [boto3]
+    REQUIRES = {'boto3': boto3}
     PARAM_ETAG = 'etag'
 
     def __init__(self, project, config):

dvc/remote/ssh.py

@@ -45,7 +45,7 @@ class RemoteSSH(RemoteBase):
     #NOTE: temporarily only absolute paths are allowed
     REGEX = r'^ssh://((?P<user>.*)@)?(?P<host>[^/]*):(?P<path>/.*)$'
 
-    REQUIRES = RemoteBase.REQUIRES + [paramiko]
+    REQUIRES = {'paramiko': paramiko}
     PARAM_MD5 = 'md5'
 
     def __init__(self, project, config):