Refs docker#565. Adds minimal implementation of env_file client-side …

…support.

docker/utils/utils.py

@@ -16,6 +16,7 @@
 import os
 import os.path
 import json
+import csv
 import shlex
 import tarfile
 import tempfile
@@ -524,16 +525,35 @@ def create_container_config(
     dns=None, volumes=None, volumes_from=None, network_disabled=False,
     entrypoint=None, cpu_shares=None, working_dir=None, domainname=None,
     memswap_limit=None, cpuset=None, host_config=None, mac_address=None,
-    labels=None, volume_driver=None
+    labels=None, volume_driver=None, env_file=None
 ):
     if isinstance(command, six.string_types):
         command = shlex.split(str(command))
+
     if isinstance(environment, dict):
         environment = [
             six.text_type('{0}={1}').format(k, v)
             for k, v in six.iteritems(environment)
         ]
 
+    if isinstance(env_file, str):
+        if os.path.isfile(env_file):
+
+            # Re-classify None to list if needed
+            if isinstance(environment, type(None)):
+                environment = []
+
+            # Re-classify string to List if needed
+            if isinstance(environment, str):
+                environment = environment.split(',')
+
+            with open(env_file, 'r') as f:
+                for line in csv.reader(f, delimiter='='):
+                    if len(line) == 2:
+                        k = line[0].strip()
+                        v = line[1].strip()
+                        environment.append('{0}={1}'.format(k, v))
+
     if labels is not None and compare_version('1.18', version) < 0:
         raise errors.InvalidVersion(
             'labels were only introduced in API version 1.18'

docs/api.md

@@ -207,6 +207,11 @@ where unit = b, k, m, or g)
 * ports (list of ints): A list of port numbers
 * environment (dict or list): A dictionary or a list of strings in the
 following format `["PASSWORD=xxx"]` or `{"PASSWORD": "xxx"}`.
+* env_file (file): A line-separated list of environment variables, such as:
+```
+USERNAME=jdoe
+PASSWORD=secret
+```
 * dns (list): DNS name servers
 * volumes (str or list):
 * volumes_from (str or list): List of container names or Ids to get volumes