feat(#130): Add support for MDC in pattern layout

log4js-node · Jun 17, 2017 · 6e15364 · 6e15364
1 parent 8befd8a
commit 6e15364
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Showing 2 changed files with 51 additions and 13 deletions.
diff --git a/lib/layouts.js b/lib/layouts.js
@@ -162,6 +162,7 @@ function dummyLayout(loggingEvent) {
  *  - %n newline
  *  - %z pid
  *  - %x{<tokenname>} add dynamic tokens to your log. Tokens are specified in the tokens parameter
+ *  - %X{<tokenname>} add dynamic tokens to your log. Tokens are specified in logger context
  * You can use %[ and %] to define a colored block.
  *
  * Tokens are specified as simple key:value objects.
@@ -181,7 +182,7 @@ function dummyLayout(loggingEvent) {
  */
 function patternLayout(pattern, tokens, timezoneOffset) {
   const TTCC_CONVERSION_PATTERN = '%r %p %c - %m%n';
-  const regex = /%(-?[0-9]+)?(\.?[0-9]+)?([[\]cdhmnprzxy%])(\{([^}]+)\})?|([^%]+)/;
+  const regex = /%(-?[0-9]+)?(\.?[0-9]+)?([[\]cdhmnprzxXy%])(\{([^}]+)\})?|([^%]+)/;
 
   pattern = pattern || TTCC_CONVERSION_PATTERN;
 
@@ -273,6 +274,16 @@ function patternLayout(pattern, tokens, timezoneOffset) {
     return null;
   }
 
+  function contextDefined(loggingEvent, specifier) {
+    const resolver = loggingEvent.context[specifier];
+
+    if (typeof resolver !== 'undefined') {
+      return typeof resolver === 'function' ? resolver(loggingEvent) : resolver;
+    }
+
+    return null;
+  }
+
   /* eslint quote-props:0 */
   const replacers = {
     'c': categoryName,
@@ -287,7 +298,8 @@ function patternLayout(pattern, tokens, timezoneOffset) {
     'y': clusterInfo,
     'z': pid,
     '%': percent,
-    'x': userDefined
+    'x': userDefined,
+    'X': contextDefined
   };
 
   function replaceToken(conversionCharacter, loggingEvent, specifier) {

diff --git a/test/tap/layouts-test.js b/test/tap/layouts-test.js
@@ -201,6 +201,16 @@ test('log4js layouts', (batch) => {
   });
 
   batch.test('patternLayout', (t) => {
+    const tokens = {
+      testString: 'testStringToken',
+      testFunction: function () {
+        return 'testFunctionToken';
+      },
+      fnThatUsesLogEvent: function (logEvent) {
+        return logEvent.level.toString();
+      }
+    };
+
     const event = {
       data: ['this is a test'],
       startTime: new Date('2010-12-05T14:18:30.045Z'), // new Date(2010, 11, 5, 14, 18, 30, 45),
@@ -209,21 +219,12 @@ test('log4js layouts', (batch) => {
         toString: function () {
           return 'DEBUG';
         }
-      }
+      },
+      context: tokens
     };
 
     const layout = require('../../lib/layouts').patternLayout;
 
-    const tokens = {
-      testString: 'testStringToken',
-      testFunction: function () {
-        return 'testFunctionToken';
-      },
-      fnThatUsesLogEvent: function (logEvent) {
-        return logEvent.level.toString();
-      }
-    };
-
     // override getTimezoneOffset
     event.startTime.getTimezoneOffset = function () {
       return 0;
@@ -369,6 +370,31 @@ test('log4js layouts', (batch) => {
       assert.end();
     });
 
+    t.test('%X{testString} should output the string stored in tokens', (assert) => {
+      testPattern(assert, layout, event, {}, '%X{testString}', 'testStringToken');
+      assert.end();
+    });
+
+    t.test('%X{testFunction} should output the result of the function stored in tokens', (assert) => {
+      testPattern(assert, layout, event, {}, '%X{testFunction}', 'testFunctionToken');
+      assert.end();
+    });
+
+    t.test('%X{doesNotExist} should output the string stored in tokens', (assert) => {
+      testPattern(assert, layout, event, {}, '%X{doesNotExist}', 'null');
+      assert.end();
+    });
+
+    t.test('%X{fnThatUsesLogEvent} should be able to use the logEvent', (assert) => {
+      testPattern(assert, layout, event, {}, '%X{fnThatUsesLogEvent}', 'DEBUG');
+      assert.end();
+    });
+
+    t.test('%X should output the string stored in tokens', (assert) => {
+      testPattern(assert, layout, event, {}, '%X', 'null');
+      assert.end();
+    });
+
     t.end();
   });