Merge pull request #563 from remind101/profile-flag

Add a --profile flag to specify default profile

stacker/commands/stacker/__init__.py

@@ -9,6 +9,7 @@
 from ...context import Context
 from ...providers.aws import default
 from ... import __version__
+from ... import session_cache
 
 logger = logging.getLogger(__name__)
 
@@ -30,6 +31,8 @@ def configure(self, options, **kwargs):
             environment=options.environment,
             validate=True)
 
+        session_cache.default_profile = options.profile
+
         options.provider_builder = default.ProviderBuilder(
             region=options.region,
             interactive=options.interactive,

stacker/commands/stacker/base.py

@@ -150,7 +150,12 @@ def add_arguments(self, parser):
                  "more than once.")
         parser.add_argument(
             "-r", "--region",
-            help="The AWS region to launch in.")
+            help="The default AWS region to use for all AWS API calls.")
+        parser.add_argument(
+            "-p", "--profile",
+            help="The default AWS profile to use for all AWS API calls. If "
+                 "not specified, the default will be according to http://bo"
+                 "to3.readthedocs.io/en/latest/guide/configuration.html.")
         parser.add_argument(
             "-v", "--verbose", action="count", default=0,
             help="Increase output verbosity. May be specified up to twice.")

stacker/providers/aws/default.py

@@ -425,9 +425,6 @@ def __init__(self, region=None, **kwargs):
         self.kwargs = kwargs
 
     def build(self, region=None, profile=None):
-        # TODO(ejholmes): This class _could_ cache built providers, however,
-        # the building of boto3 clients is _not_ threadsafe. See
-        # https://github.com/boto/boto3/issues/801#issuecomment-245455979
         if not region:
             region = self.region
         session = get_session(region=region, profile=profile)

stacker/session_cache.py

@@ -11,6 +11,8 @@
 # https://docs.python.org/3/glossary.html#term-global-interpreter-lock
 credential_cache = {}
 
+default_profile = None
+
 
 def get_session(region, profile=None):
     """Creates a boto3 session with a cache
@@ -23,6 +25,14 @@ def get_session(region, profile=None):
         :class:`boto3.session.Session`: A boto3 session with
             credential caching
     """
+    if profile is None:
+        logger.debug("No AWS profile explicitly provided. "
+                     "Falling back to default.")
+        profile = default_profile
+
+    logger.debug("Building session using profile \"%s\" in region \"%s\""
+                 % (profile, region))
+
     session = boto3.Session(region_name=region, profile_name=profile)
     c = session._session.get_component('credential_provider')
     provider = c.get_provider('assume-role')