fix: full support for Protocol Version 2 (#13)

BREAKING CHANGE: I ran into issues with the `git-http-backend` npm module when trying to add support for Git Protocol Version 2 support, so I ended up ditching it and modifying my code to replace that functionality. This change doesn't break any isomorphic-git tests, but I'm releasing this as a major version bump just to be cautious.

Author: billiegoose

middleware.js

@@ -6,13 +6,35 @@ var url = require('url')
 var auth = require('basic-auth')
 var chalk = require('chalk')
 var fixturez = require('fixturez')
-var backend = require('git-http-backend')
 var htpasswd = require('htpasswd-js')
 
 function pad (str) {
   return (str + '    ').slice(0, 7)
 }
 
+
+function matchInfo (req) {
+  var u = url.parse(req.url)
+  if (req.method === 'GET' && u.pathname.endsWith('/info/refs')) {
+    return true
+  } else {
+    return false
+  }
+}
+
+function matchService (req) {
+  var u = url.parse(req.url, true)
+  if (req.method === 'GET' && u.pathname.endsWith('/info/refs')) {
+    return u.query.service
+  }
+  if (req.method === 'POST' && req.headers['content-type'] === 'application/x-git-upload-pack-request') {
+    return 'git-upload-pack'
+  }
+  if (req.method === 'POST' && req.headers['content-type'] === 'application/x-git-receive-pack-request') {
+    return 'git-receive-pack'
+  }
+}
+
 function factory (config) {
   if (!config.root) throw new Error('Missing required "gitHttpServer.root" config option')
   if (!config.route) throw new Error('Missing required "gitHttpServer.route" config option')
@@ -23,17 +45,19 @@ function factory (config) {
   function getGitDir (req) {
     var u = url.parse(req.url)
     if (u.pathname.startsWith(config.route)) {
-      if (req.method === 'GET' && u.pathname.endsWith('/info/refs')) {
+      const info = matchInfo(req)
+      if (info) {
         let gitdir = u.pathname.replace(config.route, '').replace(/\/info\/refs$/, '').replace(/^\//, '')
         let fixtureName = path.posix.basename(gitdir)
         return f.find(fixtureName)
       }
-      if (req.method === 'POST' && req.headers['content-type'] === 'application/x-git-upload-pack-request') {
+      const service = matchService(req)
+      if (service === 'git-upload-pack') {
         let gitdir = u.pathname.replace(config.route, '').replace(/\/git-upload-pack$/, '').replace(/^\//, '')
         let fixtureName = path.posix.basename(gitdir)
         return f.find(fixtureName)
       }
-      if (req.method === 'POST' && req.headers['content-type'] === 'application/x-git-receive-pack-request') {
+      if (service === 'git-receive-pack') {
         let gitdir = u.pathname.replace(config.route, '').replace(/\/git-receive-pack$/, '').replace(/^\//, '')
         let fixtureName = path.posix.basename(gitdir)
         return f.copy(fixtureName)
@@ -43,78 +67,91 @@ function factory (config) {
   }
 
   return async function middleware (req, res, next) {
-    // handle pre-flight OPTIONS
-    if (req.method === 'OPTIONS') {
-      res.statusCode = 204
-      res.end('')
-      console.log(chalk.green('[git-http-server] 204 ' + pad(req.method) + ' ' + req.url))
-      return
-    }
-    if (!next) next = () => void(0)
-    try {
-      var gitdir = getGitDir(req)
-    } catch (err) {
-      res.statusCode = 404
-      res.end(err.message + '\n')
-      console.log(chalk.red('[git-http-server] 404 ' + pad(req.method) + ' ' + req.url))
-      return
-    }
-    if (gitdir == null) return next()
-
-    // Check for a .htaccess file
-    let data = null
     try {
-      data = fs.readFileSync(path.join(gitdir, '.htpasswd'), 'utf8')
-    } catch (err) {
-      // no .htaccess file, proceed without authentication
-    }
-    if (data) {
-      // The previous line would have failed if there wasn't an .htaccess file, so
-      // we must treat this as protected.
-      let cred = auth.parse(req.headers['authorization'])
-      if (cred === undefined) {
-        res.statusCode = 401
-        // The default reason phrase used in Node is "Unauthorized", but
-        // we will use "Authorization Required" to match what Github uses.
-        res.statusMessage = 'Authorization Required'
-        res.setHeader('WWW-Authenticate', 'Basic')
-        res.end('Unauthorized' + '\n')
-        console.log(chalk.green('[git-http-server] 401 ' + pad(req.method) + ' ' + req.url))
+      // handle pre-flight OPTIONS
+      if (req.method === 'OPTIONS') {
+        res.statusCode = 204
+        res.end('')
+        console.log(chalk.green('[git-http-server] 204 ' + pad(req.method) + ' ' + req.url))
         return
       }
-      let valid = await htpasswd.authenticate({
-        username: cred.name,
-        password: cred.pass,
-        data
-      })
-      if (!valid) {
-        res.statusCode = 401
-        // The default reason phrase used in Node is "Unauthorized", but
-        // we will use "Authorization Required" to match what Github uses.
-        res.statusMessage = 'Authorization Required'
-        res.setHeader('WWW-Authenticate', 'Basic')
-        res.end('Bad credentials' + '\n')
-        console.log(chalk.green('[git-http-server] 401 ' + pad(req.method) + ' ' + req.url))
+      if (!next) next = () => void(0)
+      try {
+        var gitdir = getGitDir(req)
+      } catch (err) {
+        res.statusCode = 404
+        res.end(err.message + '\n')
+        console.log(chalk.red('[git-http-server] 404 ' + pad(req.method) + ' ' + req.url))
         return
       }
-    }
+      if (gitdir == null) return next()
 
-    req.pipe(backend(req.url, function (err, service) {
-      if (err) {
-        res.statusCode = 500
-        res.end(err + '\n')
-        console.log(chalk.red('[git-http-server] 500 ' + pad(req.method) + ' ' + req.url))
-        return
+      // Check for a .htaccess file
+      let data = null
+      try {
+        data = fs.readFileSync(path.join(gitdir, '.htpasswd'), 'utf8')
+      } catch (err) {
+        // no .htaccess file, proceed without authentication
+      }
+      if (data) {
+        // The previous line would have failed if there wasn't an .htaccess file, so
+        // we must treat this as protected.
+        let cred = auth.parse(req.headers['authorization'])
+        if (cred === undefined) {
+          res.statusCode = 401
+          // The default reason phrase used in Node is "Unauthorized", but
+          // we will use "Authorization Required" to match what Github uses.
+          res.statusMessage = 'Authorization Required'
+          res.setHeader('WWW-Authenticate', 'Basic')
+          res.end('Unauthorized' + '\n')
+          console.log(chalk.green('[git-http-server] 401 ' + pad(req.method) + ' ' + req.url))
+          return
+        }
+        let valid = await htpasswd.authenticate({
+          username: cred.name,
+          password: cred.pass,
+          data
+        })
+        if (!valid) {
+          res.statusCode = 401
+          // The default reason phrase used in Node is "Unauthorized", but
+          // we will use "Authorization Required" to match what Github uses.
+          res.statusMessage = 'Authorization Required'
+          res.setHeader('WWW-Authenticate', 'Basic')
+          res.end('Bad credentials' + '\n')
+          console.log(chalk.green('[git-http-server] 401 ' + pad(req.method) + ' ' + req.url))
+          return
+        }
       }
 
+      const info = matchInfo(req)
+      const service = matchService(req)
       const env = req.headers['git-protocol'] ? { GIT_PROTOCOL: req.headers['git-protocol'] } : {}
 
-      res.setHeader('content-type', service.type)
+      const args = ['--stateless-rpc' ];
+      if (info) args.push('--advertise-refs')
+      args.push(gitdir)
+
+      if (info) {
+        res.setHeader('content-type', `application/x-${service}-advertisement`)
+        function pack (s) {
+            var n = (4 + s.length).toString(16);
+            return Array(4 - n.length + 1).join('0') + n + s;
+        }
+        res.write(pack('# service=' + service + '\n') + '0000');
+      } else {
+        res.setHeader('content-type', `application/x-${service}-result`)
+      }
+
+      const ps = spawn(service, args, { env })
+      req.pipe(ps.stdin)
+      ps.stdout.pipe(res)
       console.log(chalk.green('[git-http-server] 200 ' + pad(req.method) + ' ' + req.url))
-      // console.log('[git-http-server] ' + service.cmd + ' ' + service.args.concat(gitdir).join(' '))
-      var ps = spawn(service.cmd, service.args.concat(gitdir), { env })
-      ps.stdout.pipe(service.createStream()).pipe(ps.stdin)
-    })).pipe(res)
+    } catch (err) {
+      res.statusCode = 500
+      res.end(err + '\n')
+      console.log(chalk.red('[git-http-server] 500 ' + pad(req.method) + ' ' + req.url))
+    }
   }
 }
 

package-lock.json

@@ -34,7 +34,6 @@
     "chalk": "^2.4.1",
     "daemonize-process": "^1.0.9",
     "fixturez": "^1.1.0",
-    "git-http-backend": "^1.0.2",
     "htpasswd-js": "^1.0.2",
     "micro-cors": "^0.1.1",
     "minimisted": "^2.0.0",