"flush" event should always fire after "flush" call

lib/winston/transports/file.js

@@ -365,6 +365,13 @@ File.prototype.close = function () {
 File.prototype.flush = function () {
   var self = this;
 
+  // If nothing to flush, there will be no "flush" event from native stream
+  // Thus, the "open" event will never be fired (see _createStream.createAndFlush function)
+  // That means, self.opening will never set to false and no logs will be written to disk
+  if (!this._buffer.length) {
+    return self.emit('flush');
+  }
+
   //
   // Iterate over the `_buffer` of enqueued messaged
   // and then write them to the newly created stream.
@@ -434,6 +441,11 @@ File.prototype._createStream = function () {
       // and thus can emit the `open` event.
       //
       self.once('flush', function () {
+        // Because "flush" event is based on native stream "drain" event,
+        // logs could be written inbetween "self.flush()" and here
+        // Therefore, we need to flush again to make sure everything is flushed
+        self.flush();
+
         self.opening = false;
         self.emit('open', fullname);
       });

test/transports/file-open-test.js

@@ -0,0 +1,61 @@
+/*
+ * file-open-test.js: Tests for File transport "open" event
+ *
+ * (C) 2014 William Wong
+ * MIT LICENSE
+ *
+ */
+
+!function (assert, fs, os, path, vows, winston) {
+    'use strict';
+
+    vows.describe('winston/transports/file').addBatch({
+        'An instance of the File Transport': {
+            topic: function () {
+                var callback = this.callback.bind(this),
+                    logPath = path.resolve(__dirname, '../fixtures/logs/file-open-test.log');
+
+                try {
+                    fs.unlinkSync(logPath);
+                } catch (ex) {
+                    if (ex && ex.code !== 'ENOENT') { return callback(ex); }
+                }
+
+                var fileTransport = new (winston.transports.File)({
+                        filename: logPath
+                    }),
+                    logger = new (winston.Logger)({
+                        transports: [fileTransport]
+                    }),
+                    timeline = {};
+
+                fileTransport.open(function () {
+                    timeline.open = Date.now();
+
+                    setTimeout(function () {
+                        logger.info('Hello, World!', function () {
+                            timeline.logged = Date.now();
+                        });
+                    }, 100);
+
+                    setTimeout(function () {
+                        callback(null, timeline);
+                    }, 1000);
+                });
+            },
+            'should fire "open" event': function (results) {
+                assert.isTrue(!!results.open);
+            },
+            'should fire "logged" event': function (results) {
+                assert.isTrue(!!results.logged);
+            }
+        }
+    }).export(module);
+}(
+    require('assert'),
+    require('fs'),
+    require('os'),
+    require('path'),
+    require('vows'),
+    require('../../lib/winston')
+);

test/transports/file-stress-test.js

@@ -0,0 +1,76 @@
+/*
+ * file-stress-test.js: Tests for stressing File transport
+ *
+ * (C) 2014 William Wong
+ * MIT LICENSE
+ *
+ */
+
+!function (assert, fs, os, path, vows, winston) {
+    'use strict';
+
+    vows.describe('winston/transports/file').addBatch({
+        'A stressed instance of the File Transport': {
+            topic: function () {
+                var callback = this.callback.bind(this),
+                    logPath = path.resolve(__dirname, '../fixtures/logs/file-stress-test.log');
+
+                try {
+                    fs.unlinkSync(logPath);
+                } catch (ex) {
+                    if (ex && ex.code !== 'ENOENT') { return callback(ex); }
+                }
+
+                var fileTransport = new (winston.transports.File)({
+                        filename: logPath
+                    }),
+                    logger = new (winston.Logger)({
+                        transports: [fileTransport]
+                    });
+
+                fileTransport.on('open', function () {
+                    setTimeout(function () {
+                        clearInterval(interval);
+
+                        logger.query({ order: 'asc' }, function (err, results) {
+                            callback(null, results);
+                        });
+                    }, 100);
+                });
+
+                var logIndex = 0,
+                    interval = setInterval(function () {
+                        logger.info(++logIndex);
+                        stress(200);
+                    }, 0);
+
+                logger.info(++logIndex);
+                stress(200);
+
+                function stress(duration) {
+                    var startTime = Date.now();
+
+                    while (Date.now() - startTime < duration) {
+                        Math.sqrt(Math.PI);
+                    }
+                }
+            },
+            'should not skip any log lines': function (results) {
+                var testIndex = 0;
+
+                results.file.forEach(function (log) {
+                    if (+log.message !== ++testIndex) {
+                        throw new Error('Number skipped');
+                    }
+                });
+            }
+        }
+    }).export(module);
+}(
+    require('assert'),
+    require('fs'),
+    require('os'),
+    require('path'),
+    require('vows'),
+    require('../../lib/winston')
+);