Move legacy services from server.js into services/ (#1958)

This builds on the work of #1931 by moving the legacy services into `services/`.

services/jitpack/jitpack.service.js

@@ -0,0 +1,54 @@
+'use strict'
+
+const LegacyService = require('../legacy-service')
+const { makeBadgeData: getBadgeData } = require('../../lib/badge-data')
+const { addv: versionText } = require('../../lib/text-formatters')
+const { version: versionColor } = require('../../lib/color-formatters')
+
+module.exports = class Jitpack extends LegacyService {
+  static registerLegacyRouteHandler({ camp, cache }) {
+    camp.route(
+      /^\/jitpack\/v\/([^/]*)\/([^/]*)\.(svg|png|gif|jpg|json)$/,
+      cache((data, match, sendBadge, request) => {
+        const groupId = 'com.github.' + match[1] // github user
+        const artifactId = match[2] // the project's name
+        const format = match[3] // "svg"
+        const name = 'JitPack'
+
+        const pkg = groupId + '/' + artifactId + '/latest'
+        const apiUrl = 'https://jitpack.io/api/builds/' + pkg
+
+        const badgeData = getBadgeData(name, data)
+
+        request(apiUrl, (err, res, buffer) => {
+          if (err != null) {
+            badgeData.text[1] = 'inaccessible'
+            sendBadge(format, badgeData)
+            return
+          }
+          if (res.statusCode === 404) {
+            badgeData.text[1] = 'not found'
+            sendBadge(format, badgeData)
+            return
+          }
+          try {
+            const data = JSON.parse(buffer)
+            const status = data['status']
+            let color = versionColor(data['version'])
+            let version = versionText(data['version'])
+            if (status !== 'ok') {
+              color = 'red'
+              version = 'unknown'
+            }
+            badgeData.text[1] = version
+            badgeData.colorscheme = color
+            sendBadge(format, badgeData)
+          } catch (e) {
+            badgeData.text[1] = 'invalid'
+            sendBadge(format, badgeData)
+          }
+        })
+      })
+    )
+  }
+}