Merge pull request #1279 from eyoboue/nolog-function

feat: adding function(req, res) support to connectLogger options->nol…

docs/connect-logger.md

@@ -30,7 +30,7 @@ The log4js.connectLogger supports the passing of an options object that can be u
 
 - log level
 - log format string or function (the same as the connect/express logger)
-- nolog expressions (represented as a string, regexp, or array)
+- nolog expressions (represented as a string, regexp, array, or function(req, res))
 - status code rulesets
 
 For example:
@@ -97,7 +97,7 @@ app.use(
 );
 ```
 
-The log4js.connectLogger also supports a nolog option where you can specify a string, regexp, or array to omit certain log messages. Example of 1.2 below.
+The log4js.connectLogger also supports a nolog option where you can specify a string, regexp, array, or function(req, res) to omit certain log messages. Example of 1.2 below.
 
 ```javascript
 app.use(
@@ -109,6 +109,18 @@ app.use(
 );
 ```
 
+or
+
+```javascript
+app.use(
+  log4js.connectLogger(logger, {
+    level: "auto",
+    format: ":method :url",
+    nolog: (req, res) => res.statusCode < 400,
+  })
+);
+```
+
 The log4js.connectLogger can add a response of express to context if `context` flag is set to `true`.
 Application can use it in layouts or appenders.
 

lib/connect-logger.js

@@ -215,7 +215,7 @@ function matchRules(statusCode, currentLevel, ruleSet) {
  *
  *   - `format`        Format string, see below for tokens
  *   - `level`         A log4js levels instance. Supports also 'auto'
- *   - `nolog`         A string or RegExp to exclude target logs
+ *   - `nolog`         A string or RegExp to exclude target logs or function(req, res): boolean
  *   - `statusRules`   A array of rules for setting specific logging levels base on status codes
  *   - `context`       Whether to add a response of express to the context
  *
@@ -248,14 +248,18 @@ module.exports = function getLogger(logger4js, options) {
   const thisLogger = logger4js;
   let level = levels.getLevel(options.level, levels.INFO);
   const fmt = options.format || DEFAULT_FORMAT;
-  const nolog = createNoLogCondition(options.nolog);
 
   return (req, res, next) => {
     // mount safety
     if (req._logging) return next();
 
     // nologs
-    if (nolog && nolog.test(req.originalUrl)) return next();
+    if (typeof options.nolog === 'function') {
+      if (options.nolog(req, res) === true) return next();
+    } else {
+      const nolog = createNoLogCondition(options.nolog);
+      if (nolog && nolog.test(req.originalUrl)) return next();
+    }
 
     if (thisLogger.isLevelEnabled(level) || options.level === 'auto') {
       const start = new Date();

test/tap/connect-nolog-test.js

@@ -346,5 +346,43 @@ test('log4js connect logger', (batch) => {
     t.end();
   });
 
+  batch.test('nolog function', (t) => {
+    const ml = new MockLogger();
+    const cl = clm(ml, { nolog: (_req, res) => res.statusCode < 400 });
+
+    t.beforeEach(() => {
+      ml.messages = [];
+    });
+
+    t.test('check unmatch function return (statusCode < 400)', (assert) => {
+      const { messages } = ml;
+      const req = new MockRequest('my.remote.addr', 'GET', 'http://url/log');
+      const res = new MockResponse(500);
+      cl(req, res, () => {});
+      res.end('chunk', 'encoding');
+
+      assert.equal(messages.length, 1);
+      assert.ok(levels.INFO.isEqualTo(messages[0].level));
+      assert.match(messages[0].message, 'GET');
+      assert.match(messages[0].message, 'http://url');
+      assert.match(messages[0].message, 'my.remote.addr');
+      assert.match(messages[0].message, '500');
+      assert.end();
+    });
+
+    t.test('check match function return (statusCode >= 400)', (assert) => {
+      const { messages } = ml;
+      const req = new MockRequest('my.remote.addr', 'GET', 'http://url/nolog');
+      const res = new MockResponse(200);
+      cl(req, res, () => {});
+      res.end('chunk', 'encoding');
+
+      assert.equal(messages.length, 0);
+      assert.end();
+    });
+
+    t.end();
+  });
+
   batch.end();
 });