feature: add endpoint for logging instrumentation

functions/logger.js

@@ -8,9 +8,9 @@ class FirebaseTransport extends Transport {
     this._db = options.db
   }
 
-  log(info, callback) {
+  async log(info, callback) {
     try {
-      this._db.ref(`log-${new Date().getTime()}`).set(info)
+      await this._db.ref(`log-${new Date().getTime()}`).set(info)
       callback(null, info)
       this.emit('logged', info)
     } catch (err) {

lib/app/index.js

@@ -10,6 +10,7 @@ const {
   notFound,
   download,
   downloadHTML,
+  track,
 } = require('../routes')
 
 const {
@@ -92,6 +93,7 @@ const configureApplication = ({
 
   app.post('/download/html', downloadHTML(appLogger || null))
   app.post('/download', download(appLogger || null))
+  app.post('/track', track(appLogger || null))
  
 
   app.use(genericErrorHandler)

lib/routes/index.js

@@ -1,9 +1,11 @@
 const { error, notFound } = require('./error')
 const { download, downloadHTML } = require('./download')
+const { track } = require('./track')
 
 module.exports = {
   error,
   notFound,
   download,
   downloadHTML,
+  track,
 }

lib/routes/track.js

@@ -0,0 +1,24 @@
+const track = (logger) => async (req, res) => {
+  try {
+    if (!logger) {
+      return res.status(501)
+    }
+
+    const { message, service, level, env } = req.body
+
+    await logger.log({
+      message,
+      level,
+      service,
+      env: process.env.NODE_APP || env || 'N/A',
+    })
+
+    res.status(200).send({ status: 'ok' })
+  } catch (err) {
+    next(err)
+  }
+}
+
+module.exports = {
+  track,
+}

lib/static/app/logger.js

@@ -6,6 +6,23 @@ class Logger {
       'color: grey',
       'color: black'
     )
+
+    this._log({ message, level, service })
+  }
+
+  _log({ message, level, service }) {
+    return new Promise((resolve, reject) => {
+      fetch('/track', {
+        method: 'POST',
+        headers: {
+          'Accept': 'text/html, application/json',
+          'Content-Type': 'application/json',
+        },
+        body: JSON.stringify({ message, level, service, env: 'browser' })
+      })
+        .then(resolve)
+        .catch(reject)
+    })
   }
 }