Merge pull request #56 from cwahbong/log-plugin-rfc

Log plugin rfc

doc/rfcs/001_log.md

@@ -0,0 +1,78 @@
+- Feature Name: log
+- Start Date: 2016-05-07
+
+# Summary
+
+Log plugin collects all log messages from all plugins.
+
+# Motivation
+
+Println debugging is the fastest but not the best way to generate visible
+informations. For example, println logging would be difficult if we are in
+rustbox implemented terminal GUI. Plugins of Swiboe can run as different
+processs at different machines. A centralized logger can also help us to collect
+all helpful informations between different plugins.
+
+# Detailed design
+
+Current dummy implementation stills uses `println!`. The following features may be
+added later.
+
+- Configurable log level.
+- Configurable log target: not only to console output, but also to file.
+
+# API
+
+Each log function represents each logging level, with the same request and
+response foramt. Currently four levels are provided, listed as follows.
+
+- `log.debug`
+- `log.info`
+- `log.warn`
+- `log.error`
+
+## log.{debug, info, warn, error}
+
+Calling these functions to send log messages.
+
+### Request
+
+- message: The message which will be logged.
+- time: The timestamp in RFC 3339 format with timezone information.
+
+Json schema:
+
+~~~json
+{
+    "type": "object",
+    "properties": {
+        "message": {
+            "type": "string"
+        },
+        "time": {
+            "type": "string",
+        },
+    }
+}
+~~~
+
+Example:
+
+~~~json
+{
+    "message": "Example message",
+    "time": "2016-04-15T03:03:03Z",
+}
+~~~
+
+### Response
+
+Log function always respond an empty json object.
+
+Json schema:
+
+~~~json
+{
+    "type": "object",
+}
+~~~

src/plugin/list_files.rs

@@ -69,7 +69,7 @@ impl client::rpc::server::Rpc for ListFiles {
         // NOCOM handle the result
         let _ = self.client.write().unwrap().call("log.debug", &plugin::log::debug::Request {
             message: String::from("list files called"),
-            time: String::from("now"),
+            time: plugin::log::current(),
         });
 
         thread::spawn(move || {

src/plugin/log/mod.rs

@@ -5,6 +5,7 @@ use ::client;
 use ::error::Result;
 use ::plugin;
 use std::path;
+use time;
 
 
 pub struct Plugin {
@@ -26,6 +27,10 @@ impl Plugin {
     }
 }
 
+pub fn current() -> String {
+    format!("{}", time::now_utc().rfc3339())
+}
+
 mod base;
 pub mod debug;
 pub mod info;