Better handling of JSON requests

nilmdb/client/client.py

@@ -26,6 +26,7 @@ class Client(object):
         POST requests are sent with Content-Type 'application/json'
         instead of the default 'x-www-form-urlencoded'."""
         self.http = nilmdb.client.httpclient.HTTPClient(url, post_json)
+        self.post_json = post_json
 
     # __enter__/__exit__ allow this class to be a context manager
     def __enter__(self):
@@ -34,8 +35,11 @@ class Client(object):
     def __exit__(self, exc_type, exc_value, traceback):
         self.close()
 
-    def _json_param(self, data):
+    def _json_post_param(self, data):
         """Return compact json-encoded version of parameter"""
+        if self.post_json:
+            # If we're posting as JSON, we don't need to encode it further here
+            return data
         return json.dumps(data, separators=(',',':'))
 
     def close(self):
@@ -76,7 +80,7 @@ class Client(object):
         metadata."""
         params = {
             "path": path,
-            "data": self._json_param(data)
+            "data": self._json_post_param(data)
             }
         return self.http.post("stream/set_metadata", params)
 
@@ -84,7 +88,7 @@ class Client(object):
         """Update stream metadata from a dictionary"""
         params = {
             "path": path,
-            "data": self._json_param(data)
+            "data": self._json_post_param(data)
             }
         return self.http.post("stream/update_metadata", params)
 

nilmdb/server/server.py

@@ -231,26 +231,34 @@ class Stream(NilmApp):
     @cherrypy.expose
     @cherrypy.tools.json_in()
     @cherrypy.tools.json_out()
-    @exception_to_httperror(NilmDBError, LookupError, TypeError)
+    @exception_to_httperror(NilmDBError, LookupError)
     @cherrypy.tools.CORS_allow(methods = ["POST"])
     def set_metadata(self, path, data):
-        """Set metadata for the named stream, replacing any
-        existing metadata.  Data should be a json-encoded
-        dictionary"""
-        data_dict = json.loads(data)
-        self.db.stream_set_metadata(path, data_dict)
+        """Set metadata for the named stream, replacing any existing
+        metadata.  Data can be json-encoded or a plain dictionary (if
+        it was sent as application/json to begin with)"""
+        if not isinstance(data, dict):
+            try:
+                data = dict(json.loads(data))
+            except TypeError as e:
+                raise NilmDBError("can't parse 'data' parameter: " + e.message)
+        self.db.stream_set_metadata(path, data)
 
     # /stream/update_metadata?path=/newton/prep&data=<json>
     @cherrypy.expose
     @cherrypy.tools.json_in()
     @cherrypy.tools.json_out()
-    @exception_to_httperror(NilmDBError, LookupError, TypeError)
+    @exception_to_httperror(NilmDBError, LookupError)
     @cherrypy.tools.CORS_allow(methods = ["POST"])
     def update_metadata(self, path, data):
         """Update metadata for the named stream.  Data
         should be a json-encoded dictionary"""
-        data_dict = json.loads(data)
-        self.db.stream_update_metadata(path, data_dict)
+        if not isinstance(data, dict):
+            try:
+                data = dict(json.loads(data))
+            except TypeError as e:
+                raise NilmDBError("can't parse 'data' parameter: " + e.message)
+        self.db.stream_update_metadata(path, data)
 
     # /stream/insert?path=/newton/prep
     @cherrypy.expose