add property to allow an extension to be added to the filename

Resolves #225 by allowing an extension to be added to the rotated filenames.

Author: Matt Berther

README.md

@@ -28,6 +28,7 @@ The DailyRotateFile transport can rotate files by minute, hour, day, month, year
 * **options:** An object resembling https://nodejs.org/api/fs.html#fs_fs_createwritestream_path_options indicating additional options that should be passed to the file stream. (default: `{ flags: 'a' }`)
 * **auditFile**: A string representing the name of the name of the audit file. This can be used to override the default filename which is generated by computing a hash of the options object. (default: '.<optionsHash>.json')
 * **utc**: Use UTC time for date in filename. (default: false)
+* **extension**: File extension to be appended to the filename. (default: '')
 
 ## Usage
 ``` js

daily-rotate-file.js

@@ -87,7 +87,8 @@ var DailyRotateFile = function (options) {
             end_stream: true,
             audit_file: options.auditFile ? options.auditFile : path.join(self.dirname, '.' + hash(options) + '-audit.json'),
             file_options: options.options ? options.options : {flags: 'a'},
-            utc: options.utc ? options.utc : false
+            utc: options.utc ? options.utc : false,
+            extension: options.extension ? options.extension : ''
         });
 
         this.logStream.on('new', function (newFile) {

index.d.ts

@@ -47,19 +47,24 @@ declare module "winston-daily-rotate-file" {
           options?: string | object;
 
           /**
-           * A string representing the name of the name of the audit file. (default: './hash-audit.json' )
+           * A string representing the name of the name of the audit file. (default: './hash-audit.json')
            */
-          auditFile?: string
+          auditFile?: string;
 
           /**
            * A string representing the frequency of rotation. (default: 'custom')
            */
-          frequency?: string
+          frequency?: string;
 
           /**
            * A boolean whether or not to generate file name from "datePattern" in UTC format. (default: false)
            */
           utc?: boolean;
+
+          /**
+           * A string representing an extension to be added to the filename, if not included in the filename property. (default: '')
+           */
+          extension?: string;
       }
   }
 

package-lock.json

@@ -40,7 +40,7 @@
     "rimraf": "2.6.3"
   },
   "dependencies": {
-    "file-stream-rotator": "~0.5.0",
+    "file-stream-rotator": "^0.5.4",
     "object-hash": "^1.3.0",
     "triple-beam": "^1.3.0",
     "winston-transport": "^4.2.0"

package.json

@@ -100,13 +100,14 @@ describe('winston/transports/daily-rotate-file', function () {
     describe('when using a filename or dirname', function () {
         var logDir = path.join(__dirname, 'logs');
         var now = moment().utc().format('YYYY-MM-DD-HH');
-        var filename = path.join(logDir, 'application-' + now + '.log');
+        var filename = path.join(logDir, 'application-' + now + '.testlog');
         var options = {
             json: true,
             dirname: logDir,
-            filename: 'application-%DATE%.log',
+            filename: 'application-%DATE%',
             datePattern: 'YYYY-MM-DD-HH',
-            utc: true
+            utc: true,
+            extension: '.testlog'
         };
 
         beforeEach(function (done) {