1 files changed, 37 insertions, 0 deletions
diff --git a/lorrycontroller/workingstate.py b/lorrycontroller/workingstate.py
new file mode 100644
index 0000000..39d0065
--- /dev/null
+++ b/lorrycontroller/workingstate.py
@@ -0,0 +1,37 @@
+# Copyright (C) 2012  Codethink Limited
+# 
+
+import json
+import os
+import logging
+
+class WorkingStateManager(object):
+    '''Manage the working state of lorry-controller'''
+
+    def __init__(self, app):
+        self.app = app
+        self.workdir = os.path.join(self.app.settings['work-area'], 'work')
+
+    def __enter__(self):
+        self._load_state()
+        return self
+
+    def __exit__(self, exctype, excvalue, exctraceback):
+        self.save_state()
+
+    def _load_state(self):
+        self.lorry_state_file = os.path.join(self.workdir,
+                                             "last-lorry-state.json")
+        if os.path.exists(self.lorry_state_file):
+            logging.debug("Loading state file: %s" % self.lorry_state_file)
+            with open(self.lorry_state_file, "r") as fh:
+                self.lorry_state = json.load(fh)
+        else:
+            self.lorry_state = dict()
+
+    def save_state(self):
+        logging.debug("Serialising state: %s" % self.lorry_state_file)
+        with open(self.lorry_state_file, "w") as fh:
+            json.dump(self.lorry_state, fh, sort_keys=True, indent=4)
+            fh.write("\n")
+