feat: store user-agent (extracted OBS version only) for each track when uploading

logic/tracks.js

@@ -254,4 +254,31 @@ function* parseObsver2(body) {
   }
 }
 
-module.exports = { parseTrackPoints, detectFormat, parseObsver1, parseObsver2, replaceDollarNewlinesHack };
+/**
+ * This function normalizes a User-Agent header for storage in the database. It
+ * make sure that we only store the user-agent if it matches the pattern
+ * `OBS/*`, and extracts that part of the user agent, if it contains more
+ * information. This is the only part we are interested in, the
+ * remainder is too privacy sensitive to keep.
+ */
+function normalizeUserAgent(userAgent) {
+  if (!userAgent) {
+    return null;
+  }
+
+  const match = userAgent.match(/\bOBS\/[^\s]+/);
+  if (match) {
+    return match[0];
+  }
+
+  return null;
+}
+
+module.exports = {
+  detectFormat,
+  normalizeUserAgent,
+  parseObsver1,
+  parseObsver2,
+  parseTrackPoints,
+  replaceDollarNewlinesHack,
+};

logic/tracks.test.js

@@ -1,4 +1,11 @@
-const { parseTrackPoints, parseObsver1, detectFormat, parseObsver2, replaceDollarNewlinesHack } = require('./tracks');
+const {
+  detectFormat,
+  normalizeUserAgent,
+  parseObsver1,
+  parseObsver2,
+  parseTrackPoints,
+  replaceDollarNewlinesHack,
+} = require('./tracks');
 
 const { test1, test2, test3 } = require('./_tracks_testdata');
 
@@ -92,3 +99,44 @@ describe('detectFormat', () => {
     expect(detectFormat('')).toBe('invalid');
   });
 });
+
+describe('normalizeUserAgent', () => {
+  it('is a function', () => {
+    expect(typeof normalizeUserAgent).toBe('function');
+  });
+
+  it('ignores falsy values', () => {
+    expect(normalizeUserAgent(null)).toBe(null);
+    expect(normalizeUserAgent('')).toBe(null);
+  });
+
+  it('ignores normal browser agents', () => {
+    const browserAgents = [
+      'Mozilla/5.0 (Linux; Android 6.0.1; Nexus 6P Build/MMB29P) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/47.0.2526.83 Mobile Safari/537.36',
+      'Mozilla/5.0 (Linux; Android 6.0; HTC One M9 Build/MRA58K) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/52.0.2743.98 Mobile Safari/537.3',
+      'Mozilla/5.0 (Linux; Android 8.0.0; SM-G960F Build/R16NW) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/62.0.3202.84 Mobile Safari/537.36',
+      'Mozilla/5.0 (iPhone; CPU iPhone OS 11_0 like Mac OS X) AppleWebKit/604.1.38 (KHTML, like Gecko) Version/11.0 Mobile/15A5370a Safari/604.1',
+      'Mozilla/5.0 (X11; Ubuntu; Linux x86_64; rv:15.0) Gecko/20100101 Firefox/15.0.1',
+    ];
+
+    for (const browserAgent of browserAgents) {
+      expect(normalizeUserAgent(browserAgent)).toBe(null);
+    }
+  });
+
+  it('detects OBS versions', () => {
+    const agents = ['OBS/123', 'OBS/2', 'OBS/1.2.3.4.5-rc123'];
+
+    for (const agent of agents) {
+      expect(normalizeUserAgent(agent)).toBe(agent);
+    }
+  });
+
+  it('extracts OBS versions from extended formats', () => {
+    const agents = ['foo OBS/123', 'OBS/123 bar', 'foo OBS/123 bar'];
+
+    for (const agent of agents) {
+      expect(normalizeUserAgent(agent)).toBe('OBS/123');
+    }
+  });
+});

models/Track.js

@@ -9,6 +9,7 @@ const TrackSchema = new mongoose.Schema(
     description: String,
     body: String,
     visible: Boolean,
+    uploadedByUserAgent: String,
     numEvents: { type: Number, default: 0 },
     comments: [{ type: mongoose.Schema.Types.ObjectId, ref: 'Comment' }],
     author: { type: mongoose.Schema.Types.ObjectId, ref: 'User' },

routes/api/tracks.js

@@ -7,7 +7,7 @@ const User = mongoose.model('User');
 const busboy = require('connect-busboy');
 const auth = require('../auth');
 const currentTracks = new Map();
-const { parseTrackPoints } = require('../../logic/tracks');
+const { parseTrackPoints, normalizeUserAgent } = require('../../logic/tracks');
 const wrapRoute = require('../../_helpers/wrapRoute');
 
 // Preload track objects on routes with ':track'
@@ -216,6 +216,7 @@ router.post(
 
     if (track.body) {
       trackData.points = Array.from(parseTrackPoints(track.body));
+      track.uploadedByUserAgent = normalizeUserAgent(req.headers['user-agent']);
     }
 
     track.visible = track.author.areTracksVisibleForAll;
@@ -242,6 +243,7 @@ router.post(
     const trackData = new TrackData();
     track.trackData = trackData._id;
     track.author = user;
+    track.uploadedByUserAgent = normalizeUserAgent(req.headers['user-agent']);
 
     await track.save();
     await trackData.save();
@@ -372,6 +374,7 @@ router.put(
         req.track.trackData = trackData._id;
       }
       trackData.points = Array.from(parseTrackPoints(req.track.body));
+      req.track.uploadedByUserAgent = normalizeUserAgent(req.headers['user-agent']);
       await trackData.save();
     }
 

routes/auth.js

@@ -2,7 +2,8 @@ const jwt = require('express-jwt');
 const secret = require('../config').secret;
 
 function getTokenFromHeader(req) {
-  const [tokenType, token] = req.headers.authorization?.split(' ') || [];
+  const authorization = req.headers.authorization;
+  const [tokenType, token] = (authorization && authorization.split(' ')) || [];
 
   if (tokenType === 'Token' || tokenType === 'Bearer') {
     return token;