From efe21b27cdfda27f9edb5a839bb1a6b65e1dcfec Mon Sep 17 00:00:00 2001
From: Scott Schneider <scott@mesosphere.com>
Date: Tue, 20 Dec 2016 10:41:45 -0800
Subject: [PATCH] Allow configuration to be defined in an ENV var

If `ENV['VMPOOLER_CONFIG']` is defined, it is read in as a YAML
configuration.  This allows vmpooler to run in a docker daemon via
`docker run -e VMPOOLER_CONFIG -p 80:4567 -it vmpooler` rather than
embedding a YAML file within the container.
---
 lib/vmpooler.rb | 15 +++++++++++----
 1 file changed, 11 insertions(+), 4 deletions(-)

diff --git a/lib/vmpooler.rb b/lib/vmpooler.rb
index 0e5707c..844aa6e 100644
--- a/lib/vmpooler.rb
+++ b/lib/vmpooler.rb
@@ -21,11 +21,18 @@ module Vmpooler
   end
 
   def self.config(filepath='vmpooler.yaml')
-    # Load the configuration file
-    config_file = File.expand_path(filepath)
-    parsed_config = YAML.load_file(config_file)
+    parsed_config = {}
 
-    # Set some defaults
+    if ENV['VMPOOLER_CONFIG']
+      # Load configuration from ENV
+      parsed_config = YAML.load(ENV['VMPOOLER_CONFIG'])
+    else
+      # Load the configuration file from disk
+      config_file = File.expand_path(filepath)
+      parsed_config = YAML.load_file(config_file)
+    end
+
+    # Set some configuration defaults
     parsed_config[:redis]             ||= {}
     parsed_config[:redis]['server']   ||= 'localhost'
     parsed_config[:redis]['data_ttl'] ||= 168