Helper method to get options from environment variables

arkindex/__init__.py

-from arkindex.client import ArkindexClient  # noqa: F401
+from arkindex.client import ArkindexClient, options_from_env  # noqa: F401

arkindex/client.py

 """
 Arkindex API Client
 """
-import os.path
+import os
 import apistar
 import logging
 import yaml
@@ -16,6 +16,22 @@ BASE_DIR = os.path.dirname(os.path.abspath(__file__))
 logger = logging.getLogger(__name__)
 
 
+def options_from_env():
+    """
+    Get API client keyword arguments from environment variables.
+    """
+    options = {}
+    if 'ARKINDEX_API_TOKEN' in os.environ:
+        options['token'] = os.environ.get('ARKINDEX_API_TOKEN')
+
+    if 'ARKINDEX_API_INTERNAL_URL' in os.environ:
+        options['base_url'] = os.environ.get('ARKINDEX_API_INTERNAL_URL')
+    elif 'ARKINDEX_API_URL' in os.environ:
+        options['base_url'] = os.environ.get('ARKINDEX_API_URL')
+
+    return options
+
+
 class ArkindexClient(apistar.Client):
     """
     An Arkindex API client.