Merge pull request #235 from hybridgroup/add/log-levels

Add log levels

lib/logger.js

@@ -8,10 +8,6 @@
 
 "use strict";
 
-var getArgs = function(args) {
-  return args.length >= 1 ? [].slice.call(args, 0) : [];
-};
-
 var levels = ["debug", "info", "warn", "error", "fatal"];
 
 var BasicLogger = require('./logger/basic_logger'),
@@ -27,12 +23,19 @@ var Logger = module.exports = {};
 // logger - logger object to use. Defaults to a BasicLogger, or a NullLogger if
 // false is supplied
 //
+// level - logging level to use. if supplied, will only log to specified level
+// or above
+//
 // Returns the new logger instance
-Logger.setup = function setup(logger) {
+Logger.setup = function setup(logger, level) {
   if (logger == null) { logger = BasicLogger; }
 
   this.logger = logger || NullLogger;
 
+  if (typeof level === 'string') {
+    setLogLevel(level);
+  }
+
   return this.logger;
 };
 
@@ -43,5 +46,28 @@ Logger.toString = function() {
 levels.forEach(function(level) {
   Logger[level] = function() {
     return this.logger[level].apply(this.logger, arguments);
-  }
+  };
 });
+
+var setLogLevel = function(level) {
+  var index = levels.indexOf(level),
+      active,
+      ignored;
+
+  if (index < 0) {
+    throw new Error("Invalid Log Level specified");
+  }
+
+  active = levels.slice(index);
+  ignored = levels.slice(0, index);
+
+  active.forEach(function(level) {
+    Logger[level] = function() {
+      return this.logger[level].apply(this.logger, arguments);
+    };
+  });
+
+  ignored.forEach(function(level) {
+    Logger[level] = function() {};
+  });
+}

spec/lib/logger.spec.js

@@ -82,4 +82,38 @@ describe('Logger', function() {
       });
     });
   });
+
+  describe("log levels", function() {
+    var logger;
+
+    beforeEach(function() {
+      logger = {
+        debug: spy(),
+        info: spy(),
+        warn: spy(),
+        error: spy(),
+        fatal: spy()
+      };
+
+      Logger.setup(logger, 'warn');
+    });
+
+    it("prevents logging of anything below the specified log level", function() {
+      Logger.debug("debug message");
+      Logger.info("info message");
+
+      expect(logger.debug).to.not.be.called;
+      expect(logger.info).to.not.be.called;
+    });
+
+    it("still logs anything equal or greater than the specified log level", function() {
+      Logger.warn("warn message");
+      Logger.error("error message");
+      Logger.fatal("fatal message");
+
+      expect(logger.warn).to.be.calledWith('warn message');
+      expect(logger.error).to.be.calledWith('error message');
+      expect(logger.fatal).to.be.calledWith('fatal message');
+    });
+  });
 });