Add support for YAML lorries

This commit makes lorry-controller understand YAML lorry files. If
the file cannot be parsed as YAML then we fall back to attempting
to load it as JSON, before giving up on loading it completely.

The test for broken JSON is modified to use a string which is
invalid for both YAML and JSON.

Change-Id: If83e2e44b38e6fb63dbf0b857e143fdcabab78ac

2 files changed, 7 insertions, 3 deletions

diff --git a/lorrycontroller/readconf.py b/lorrycontroller/readconf.py
index aee2462..162e116 100644
--- a/lorrycontroller/readconf.py
+++ b/lorrycontroller/readconf.py
@@ -23,6 +23,7 @@ import re
 
 import bottle
 import cliapp
+import yaml
 
 import lorrycontroller
 
@@ -238,9 +239,12 @@ class ReadConfiguration(lorrycontroller.LorryControllerRoute):
 
         try:
             with open(filename) as f:
-                obj = json.load(f)
+                try:
+                    obj = yaml.safe_load(f)
+                except yaml.YAMLError:
+                    obj = json.load(f)
         except ValueError as e:
-            logging.error('JSON problem in %s', filename)
+            logging.error('YAML and JSON problem in %s', filename)
             return []
 
         if type(obj) != dict:
diff --git a/yarns.webapp/060-validation.yarn b/yarns.webapp/060-validation.yarn
index 076879b..29bc7ca 100644
--- a/yarns.webapp/060-validation.yarn
+++ b/yarns.webapp/060-validation.yarn
@@ -166,7 +166,7 @@ Make sure WEBAPP handles there not being any `.lorry` files.
 
 Add a `.lorry` file that contains broken JSON.
 
-    GIVEN Lorry file CONFGIT/notjson.lorry with THIS IS NOT JSON
+    GIVEN Lorry file CONFGIT/notjson.lorry with { THIS IS NOT JSON ]
     WHEN admin makes request POST /1.0/read-configuration
     THEN response matches "has been updated"
     AND STATEDB is empty