Adding private environment variable values for deploy - supports non-hard coded values in the config

asaolabs · asaolabs · commit 65f35f03e18d · 2017-07-12T09:33:15.000-04:00
diff --git a/README.rst b/README.rst
@@ -13,9 +13,10 @@ python-λ
 Python-lambda is a toolset for developing and deploying *serverless* Python code in AWS Lambda.
 
 NOTE: CHANGES FROM BASE REPOSITORY
-============================
+==================================
 
 * Adding Python 3.6 support for the local environment & the lambda runtime
+* Supports "secret" environment variable values by reading them from the local environment during deploy instead of using hard-coded ones in the config file.
 
 
 A call for contributors
@@ -167,6 +168,13 @@ Lambda functions support environment variables. In order to set environment vari
     env1: foo
     env2: baz
 
+You can also keep "secrets" out of your config file by using the following syntax ``${}`` to read the values from your current/local environment.
+
+.. code:: yaml
+
+  environment_variables:
+    env3: ${LOCAL_ENVIRONMENT_VARIABLE_NAME}
+
 This would create environment variables in the lambda instance upon deploy. If your functions don't need environment variables, simply leave this section out of your config.
 
 
diff --git a/aws_lambda/aws_lambda.py b/aws_lambda/aws_lambda.py
@@ -20,6 +20,7 @@
 from .helpers import mkdir
 from .helpers import read
 from .helpers import timestamp
+from .helpers import get_environment_variable_value
 
 
 log = logging.getLogger(__name__)
@@ -375,7 +376,7 @@ def create_function(cfg, path_to_zip_file):
         kwargs.update(
             Environment={
                 'Variables': {
-                    key: value
+                    key: get_environment_variable_value(value)
                     for key, value
                     in cfg.get('environment_variables').items()
                 }
@@ -422,7 +423,7 @@ def update_function(cfg, path_to_zip_file):
         kwargs.update(
             Environment={
                 'Variables': {
-                    key: value
+                    key: get_environment_variable_value(value)
                     for key, value
                     in cfg.get('environment_variables').items()
                 }
diff --git a/aws_lambda/helpers.py b/aws_lambda/helpers.py
@@ -2,7 +2,7 @@
 import os
 import zipfile
 import datetime as dt
-
+import re
 
 def mkdir(path):
     if not os.path.exists(path):
@@ -31,3 +31,12 @@ def archive(src, dest, filename):
 def timestamp(fmt='%Y-%m-%d-%H%M%S'):
     now = dt.datetime.utcnow()
     return now.strftime(fmt)
+
+
+def get_environment_variable_value(val):
+    env_val = val
+    if val is not None and isinstance(val, str):
+        match = re.search(r'^\${(?P<environment_key_name>\w+)*}$', val)
+        if match is not None:
+            env_val = os.environ.get(match.group('environment_key_name'))
+    return env_val
