A few stability improvements, more to come.

example/loggingWebServer.js

@@ -1,7 +1,8 @@
 var http = require("http"),
     elf = require("../lib/elf-logger"),
-    responseString = "Hello World!\nNow go look in the './log' folder to see logging output.";
+    responseString = "Hello World!\nNow go look in the 'log' folder to see logging output.";
 
+// Create a simple, standard Node HTTP server.
 var httpServer = http.createServer(function (req, res) {
     res.writeHead(200, {
         "Content-Type": "text/plain;charset=utf-8",
@@ -10,23 +11,28 @@ var httpServer = http.createServer(function (req, res) {
     res.write(responseString, "utf8");
     res.end();
 });
+// Begin listening on port 8080.
 httpServer.listen(8080);
 
 
-// You may pass an 'options' argument with a 'stream'
-// property. It's value should be a WritableStream to
-// write logging output to.  If a 'stream' prop is
-// present, only the 'stream' and 'fields' are valid.
-//var stdoutLog = elf.createLogger(httpServer, {
+// You may pass an 'options' argument with a 'stream' property. It's value
+// should be a WritableStream to write logging output to.  If a 'stream' prop
+// is present, only the 'stream' and 'fields' are valid.
+var stdoutLog = elf.createLogger(httpServer, {
     // This logger will print all logging output to 'stdout'
-//    stream: process.stdout,
+    stream: process.stdout,
     // Log only a few fields
-//    fields: ['date','time','c-ip','cs-method','cs-uri','sc-status']
-//});
+    fields: ['date','time','c-ip','cs-method','cs-uri','sc-status']
+});
 
 
-// Omitting the second 'options' argument creates
-// a logger instance with elf.defaultOptions
+// For better organization, and log-splitting, etc., you would probably rather
+// supply a 'template' (and maybe 'dir') properties. The 'template' should be
+// a function that is called for each log entry and should return the path and
+// name of file that the entry should log to. The function is passed the
+// entry's #Fields as an object literal for an argument. The 'dirs' prop, if
+// present, will prefix the 'dir' value before the 'template' value to
+// determine the actual log file location.
 var filesystemLog = elf.createLogger(httpServer, {
     template: function(fields) {
         var name = "";
@@ -45,3 +51,14 @@ var filesystemLog = elf.createLogger(httpServer, {
     dir: 'logs',
     fields: ['date','time','c-ip','cs-method','cs-uri','sc-status']
 });
+
+
+// And finally, you may pass a String to the 'template' property, which may
+// contain the names of individual #Fields values, surrounded by {}s. For
+// each entry, the {} field will be replaced with the entry's actual value in
+// order to determine which log file the entry should be recorded to.
+var methodLog = elf.createLogger(httpServer, {
+    template: "METHOD/{cs-method}.log",
+    dir: 'logs',
+    fields: ['date','time','c-ip','cs-uri','sc-status','cs(host)']
+});

lib/elf-logger.js

@@ -19,6 +19,7 @@ exports.createLogger = function(httpServer, options) {
 };
 
 
+var isServer;
 
 // We need to modify the standard 'http' library a little bit, to hook into
 // logging events that otherwise aren't exposed.
@@ -82,6 +83,15 @@ exports.createLogger = function(httpServer, options) {
         }
         return rtn;
     }
+
+    // TODO eventually remove sendHeader(), writeHeader(), (when ry does)
+    http.ServerResponse.prototype.sendHeader = http.ServerResponse.prototype.writeHead;
+    http.ServerResponse.prototype.writeHeader = http.ServerResponse.prototype.writeHead;
+
+    // We need to define this function while we're in the native 'http' scope
+    isServer = function(server) {
+        return server instanceof http.Server;
+    }
 })(require("http"));
 
 
@@ -98,6 +108,8 @@ exports.createLogger = function(httpServer, options) {
 // function. Any number of ElfLoggers can be created for a single
 // HttpServer instance.
 function ElfLogger(httpServer, options) {
+    if (!isServer(httpServer)) throw new Error('"createLogger" expects an \'http.Server\' instance.');
+
     var self = this, i=options.fields.length;
     extend(self, options);
     while (i--) {
@@ -166,7 +178,6 @@ extend(ElfEntry.prototype, {
 
             } else { // go through the standard filename templating
                 var logPath = logger.getEntryFilename(this);
-                //sys.puts(logPath);
                 writeToLog(logPath, this, logger);
             }
         }, this);
@@ -206,18 +217,16 @@ function ElfLog(filepath, logger) {
         logName = path.basename(filepath),
         dirs = getDirs(filepath);
 
-    //sys.puts(JSON.stringify(dirs));
-    //sys.puts(logName);
-
     if (dirs.length > 0) {
+
         var dCount = 0, dirExists = true;
-
         var checkDir = function() {
                 var subDirs = dirs.slice(0, dCount+1);
-                subDirs = subDirs.length === 1 && subDirs[0] === '' ?
-                    '/' : subDirs.join('/');
+                subDirs = subDirs.length === 1 ?
+                    (subDirs[0] || '/') :
+                    path.join.apply(path, subDirs);
+
                 if (dirExists) {
-                    //sys.puts('stat: ' + subDirs);
                     fs.stat(subDirs, function(err, stat) {
                         if (stat) {
                             dCount++;
@@ -232,7 +241,6 @@ function ElfLog(filepath, logger) {
                             self.createWriteStream();
                     });
                 } else {
-                    sys.puts('mkdir: ' + subDirs);
                     fs.mkdir(subDirs, 0777, function(err) {
                         dCount++;
                         if (dCount < dirs.length)
@@ -243,9 +251,17 @@ function ElfLog(filepath, logger) {
                 }
         }
         checkDir();
-
+        
     } else {
-        this.createWriteStream();
+
+        fs.stat(subDirs, function(err, stat) {
+            if (stat) {
+                self.createWriteStream();
+            } else {
+                self.createWriteStream();
+            }
+        });
+
     }
 }
 
@@ -257,9 +273,6 @@ extend(ElfLog.prototype, {
             'mode': 0666
         });
         this.ready = true;
-        this.flushQueue();
-    },
-    flushQueue: function() {
         this.queuedEntries.forEach(function(entry) {
             this.writeEntry(entry);
         }, this);