Changes between Version 2 and Version 3 of doc/developer/WiFiDog_V2

Timestamp:

03/25/08 22:00:26 (14 years ago)

Author:

papril

Comment:

--

doc/developer/WiFiDog_V2

@@ -13 +13 @@
  * QoS support
  * Versioned and more standard protocol
+ * Better URLs (RESTful philosophy?)
 
 = Proposed architecture and ideas =
@@ -39 +40 @@
  * If it failed contacting the auth server twice, apply the "what to do when the internet is down" policy (either "allow" or "reject but explain what's going on")
  * When it receives the status from the auth server, it will also receive a list of "who's supposed to be connected". It will do a DIFF of this with what it has to remove/add who should be there
+
+== Things tested ==
+
+=== JSON for protocol ===
+XML or YAML would have been great, but I tried to use Syck (http://whytheluckystiff.net/syck/) and it didn't seem trivial to use, it looks like it supports a stream parser, we need something more like a DOM to find values returned.
+
+JSON (with json-c-0.7) gives us that in C and is quite elegant.
+
+Here's how we can generate JSON:
+{{{
+struct json_object *status_object = json_object_new_object();
+json_object_object_add(status_object, "wifidog_version", json_object_new_string(VERSION));
+json_object_object_add(status_object, "protocol_version", json_object_new_double(2.0));
+json_object_object_add(status_object, "node_id", json_object_new_string(node_id));
+json_object_object_add(status_object, "fetch_config", json_object_new_boolean(1));
+
+struct json_object *node_status_object = json_object_new_object();
+json_object_object_add(node_status_object, "wifidog_uptime", json_object_new_int(25));
+json_object_object_add(node_status_object, "sys_uptime", json_object_new_int(get_sys_uptime()));
+json_object_object_add(node_status_object, "sys_loadavg", json_object_new_double(get_sys_loadavg()));
+json_object_object_add(node_status_object, "sys_memfree", json_object_new_int(get_sys_memfree()));
+
+char * json = json_object_to_json_string(status_object);
+}}}
+
+It returns the JSON string.
+
+To parse:
+
+{{{
+struct json_object * json_object = json_tokener_parse(the_string);
+struct json_object * value_json_object = json_object_object_get(json_object, "node_id");
+printf("%s\n", json_object_get_string(value_json_object));
+}}}
+
+This will retrieve the string value of "node_id" at the first level in the tree.