Allow setting logger name to separate components (#355)

lib/logger.js

@@ -44,7 +44,17 @@ Logger.prototype.wrap = function () {
   })
 
   // Expose `child` method for creating new wrapped loggers
-  fn.child = (attrs) => this.child(attrs, true).wrap()
+  fn.child = (attrs) => {
+    // Bunyan doesn't allow you to overwrite name…
+    const name = attrs.name
+    delete attrs.name
+    const log = this.child(attrs, true)
+
+    // …Sorry, bunyan, doing it anwyway
+    if (name) log.fields.name = name
+
+    return log.wrap()
+  }
 
   // Expose target logger
   fn.target = logger

lib/middleware/logging.js

@@ -11,7 +11,7 @@ module.exports = function logRequest ({logger}) {
     res.setHeader('x-request-id', req.id)
 
     // Make a logger available on the request
-    req.log = logger.wrap().child({id: req.id})
+    req.log = logger.wrap().child({name: 'http', id: req.id})
 
     // Request started
     req.log.trace({req}, `${req.method} ${req.url}`)

lib/robot.js

@@ -93,7 +93,7 @@ class Robot {
 
     return this.events.on(name, async event => {
       if (!action || action === event.payload.action) {
-        const log = this.log.child({id: event.id})
+        const log = this.log.child({name: 'event', id: event.id})
 
         try {
           const github = await this.auth(event.payload.installation.id, log)
@@ -141,7 +141,7 @@ class Robot {
       debug: process.env.LOG_LEVEL === 'trace',
       host: process.env.GHE_HOST || 'api.github.com',
       pathPrefix: process.env.GHE_HOST ? '/api/v3' : '',
-      logger: log.child({installation: id})
+      logger: log.child({name: 'github', installation: id})
     })
 
     if (id) {

test/logger.test.js

@@ -0,0 +1,29 @@
+const logger = require('../lib/logger')
+
+describe('logger', () => {
+  let output
+
+  beforeEach(() => {
+    output = []
+
+    logger.addStream({
+      level: 'trace',
+      type: 'raw',
+      stream: {write: log => output.push(log)}
+    })
+  })
+
+  describe('child', () => {
+    test('sets attributes', () => {
+      const child = logger.wrap().child({user: 'me'})
+      child.debug('attributes will get added to this')
+      expect(output[0]).toHaveProperty('user', 'me')
+    })
+
+    test('allows setting the name', () => {
+      const child = logger.wrap().child({name: 'test'})
+      child.debug('hello')
+      expect(output[0]).toHaveProperty('name', 'test')
+    })
+  })
+})