Drop gif + png, and redirect png to raster.shields.io (badges#3644)

1. Remove rasterization support from the server. This responsibility is delegated to a raster server which proxies the SVG badges and renders them.
2. When a raster server URL is configured, 301 redirect all .png badges to the identical URL on the raster server.
    `https://img.shields.io/npm/v/express.png?style=flat-square` ↪️`https://raster.shields.io/npm/v/express.png?style=flat-square`
3. For configured redirects, redirect to the canonical URL on the raster server.
    `https://img.shields.io/vso/build/totodem/8cf3ec0e-d0c2-4fcd-8206-ad204f254a96/2.png?style=flat-square`
    ↪️`https://img.shields.io/azure-devops/build/totodem/8cf3ec0e-d0c2-4fcd-8206-ad204f254a96/2.png?style=flat-square`
4. Redirect the "legacy badge old version" to the appropriate URL on the raster server.
5. When no raster server is configured (e.g. PRs), render an SVG containing **404 | raster badges not available** for all `.png` badges. (Note that the raster server can be self-hosted; however, this is deferred to a later PR.)
5. Drop support for jpg and gif which are very infrequently used (see badges#3112). Render an SVG containing **410 | jpg no longer available**.
7. ~~Remove raster dependencies.~~ Remove the raster cache (which is only used in the CLI, and therefore pointless).
8. Move the LRUCache code out of the npm package.
8. A wee bit of refactoring in `server.js`.

Ref badges#3112
Close badges#3631

Dockerfile

@@ -1,7 +1,5 @@
 FROM node:8-alpine
 
-RUN apk add --no-cache gettext imagemagick librsvg git
-
 RUN mkdir -p /usr/src/app
 RUN mkdir /usr/src/app/private
 WORKDIR /usr/src/app

config/custom-environment-variables.yml

@@ -14,6 +14,8 @@ public:
 
   redirectUri: 'REDIRECT_URI'
 
+  rasterUrl: 'RASTER_URL'
+
   cors:
     allowedOrigin:
       __name: 'ALLOWED_ORIGIN'

config/shields-io-production.yml

@@ -11,6 +11,8 @@ public:
 
   redirectUrl: 'https://shields.io/'
 
+  rasterUrl: 'https://raster.shields.io'
+
 private:
   # These are not really private; they should be moved to `public`.
   shields_ips: ['192.99.59.72', '51.254.114.150', '149.56.96.133']

config/test.yml

@@ -7,4 +7,6 @@ public:
 
   redirectUrl: 'http://badge-server.example.com'
 
+  rasterUrl: 'http://raster.example.com'
+
   handleInternalErrors: false

core/badge-urls/make-badge-url.js

@@ -1,5 +1,6 @@
 'use strict'
 
+const { URL } = require('url')
 const queryString = require('query-string')
 const pathToRegexp = require('path-to-regexp')
 
@@ -134,11 +135,21 @@ function dynamicBadgeUrl({
   return `${baseUrl}/badge/dynamic/${datatype}.${format}?${outQueryString}`
 }
 
+function rasterRedirectUrl({ rasterUrl }, badgeUrl) {
+  // Ensure we're always using the `rasterUrl` by using just the path from
+  // the request URL.
+  const { pathname, search } = new URL(badgeUrl, 'https://bogus.test')
+  const result = new URL(pathname, rasterUrl)
+  result.search = search
+  return result
+}
+
 module.exports = {
   badgeUrlFromPath,
   badgeUrlFromPattern,
   encodeField,
   staticBadgeUrl,
   queryStringStaticBadgeUrl,
   dynamicBadgeUrl,
+  rasterRedirectUrl,
 }

core/base-service/base.spec.js

@@ -316,7 +316,7 @@ describe('BaseService', function() {
   })
 
   describe('ScoutCamp integration', function() {
-    const expectedRouteRegex = /^\/foo\/([^/]+?)\.(svg|png|gif|jpg|json)$/
+    const expectedRouteRegex = /^\/foo\/([^/]+?)\.(svg|json)$/
 
     let mockCamp
     let mockHandleRequest

core/base-service/legacy-request-handler.js

@@ -4,7 +4,6 @@
 const domain = require('domain')
 const request = require('request')
 const queryString = require('query-string')
-const LruCache = require('../../gh-badges/lib/lru-cache')
 const makeBadge = require('../../gh-badges/lib/make-badge')
 const log = require('../server/log')
 const { setCacheHeaders } = require('./cache-headers')
@@ -14,6 +13,7 @@ const {
   ShieldsRuntimeError,
 } = require('./errors')
 const { makeSend } = require('./legacy-result-sender')
+const LruCache = require('./lru-cache')
 const coalesceBadge = require('./coalesce-badge')
 
 // We avoid calling the vendor's server for computation of the information in a

core/base-service/legacy-result-sender.js

@@ -1,15 +1,6 @@
 'use strict'
 
-const fs = require('fs')
-const path = require('path')
 const stream = require('stream')
-const svg2img = require('../../gh-badges/lib/svg-to-img')
-const log = require('../server/log')
-
-const internalError = fs.readFileSync(
-  path.resolve(__dirname, '..', 'server', 'error-pages', '500.html'),
-  'utf-8'
-)
 
 function streamFromString(str) {
   const newStream = new stream.Readable()
@@ -25,21 +16,6 @@ function sendSVG(res, askres, end) {
   end(null, { template: streamFromString(res) })
 }
 
-function sendOther(format, res, askres, end) {
-  askres.setHeader('Content-Type', `image/${format}`)
-  svg2img(res, format)
-    // This interacts with callback code and can't use async/await.
-    // eslint-disable-next-line promise/prefer-await-to-then
-    .then(data => {
-      end(null, { template: streamFromString(data) })
-    })
-    .catch(err => {
-      // This emits status code 200, though 500 would be preferable.
-      log.error('svg2img error', err)
-      end(internalError)
-    })
-}
-
 function sendJSON(res, askres, end) {
   askres.setHeader('Content-Type', 'application/json')
   askres.setHeader('Access-Control-Allow-Origin', '*')
@@ -52,7 +28,7 @@ function makeSend(format, askres, end) {
   } else if (format === 'json') {
     return res => sendJSON(res, askres, end)
   } else {
-    return res => sendOther(format, res, askres, end)
+    throw Error(`Unrecognized format: ${format}`)
   }
 }
 

core/base-service/redirector.js

@@ -62,8 +62,11 @@ module.exports = function redirector(attrs) {
       return route
     }
 
-    static register({ camp, requestCounter }) {
-      const { regex, captureNames } = prepareRoute(this.route)
+    static register({ camp, requestCounter }, { rasterUrl }) {
+      const { regex, captureNames } = prepareRoute({
+        ...this.route,
+        withPng: Boolean(rasterUrl),
+      })
 
       const serviceRequestCounter = this._createServiceRequestCounter({
         requestCounter,
@@ -104,7 +107,9 @@ module.exports = function redirector(attrs) {
 
         // The final capture group is the extension.
         const format = match.slice(-1)[0]
-        const redirectUrl = `${targetPath}.${format}${urlSuffix}`
+        const redirectUrl = `${
+          format === 'png' ? rasterUrl : ''
+        }${targetPath}.${format}${urlSuffix}`
         trace.logTrace('outbound', emojic.shield, 'Redirect URL', redirectUrl)
 
         ask.res.statusCode = 301

core/base-service/redirector.spec.js

@@ -75,7 +75,10 @@ describe('Redirector', function() {
         transformPath,
         dateAdded,
       })
-      ServiceClass.register({ camp }, {})
+      ServiceClass.register(
+        { camp },
+        { rasterUrl: 'http://raster.example.test' }
+      )
     })
 
     it('should redirect as configured', async function() {
@@ -90,7 +93,7 @@ describe('Redirector', function() {
       expect(headers.location).to.equal('/new/service/hello-world.svg')
     })
 
-    it('should preserve the extension', async function() {
+    it('should redirect raster extensions to the canonical path as configured', async function() {
       const { statusCode, headers } = await got(
         `${baseUrl}/very/old/service/hello-world.png`,
         {
@@ -99,7 +102,9 @@ describe('Redirector', function() {
       )
 
       expect(statusCode).to.equal(301)
-      expect(headers.location).to.equal('/new/service/hello-world.png')
+      expect(headers.location).to.equal(
+        'http://raster.example.test/new/service/hello-world.png'
+      )
     })
 
     it('should forward the query params', async function() {

core/base-service/route.js

@@ -26,18 +26,16 @@ function assertValidRoute(route, message = undefined) {
   Joi.assert(route, isValidRoute, message)
 }
 
-function prepareRoute({ base, pattern, format, capture }) {
+function prepareRoute({ base, pattern, format, capture, withPng }) {
+  const extensionRegex = ['svg', 'json']
+    .concat(withPng ? ['png'] : [])
+    .join('|')
   let regex, captureNames
   if (pattern === undefined) {
-    regex = new RegExp(
-      `^${makeFullUrl(base, format)}\\.(svg|png|gif|jpg|json)$`
-    )
+    regex = new RegExp(`^${makeFullUrl(base, format)}\\.(${extensionRegex})$`)
     captureNames = capture || []
   } else {
-    const fullPattern = `${makeFullUrl(
-      base,
-      pattern
-    )}.:ext(svg|png|gif|jpg|json)`
+    const fullPattern = `${makeFullUrl(base, pattern)}.:ext(${extensionRegex})`
     const keys = []
     regex = pathToRegexp(fullPattern, keys, {
       strict: true,

core/base-service/route.spec.js

@@ -33,9 +33,6 @@ describe('Route helpers', function() {
     test(namedParams, () => {
       forCases([
         given('/foo/bar.bar.bar.svg'),
-        given('/foo/bar.bar.bar.png'),
-        given('/foo/bar.bar.bar.gif'),
-        given('/foo/bar.bar.bar.jpg'),
         given('/foo/bar.bar.bar.json'),
       ]).expect({ namedParamA: 'bar.bar.bar' })
     })
@@ -64,9 +61,6 @@ describe('Route helpers', function() {
     test(namedParams, () => {
       forCases([
         given('/foo/bar.bar.bar.svg'),
-        given('/foo/bar.bar.bar.png'),
-        given('/foo/bar.bar.bar.gif'),
-        given('/foo/bar.bar.bar.jpg'),
         given('/foo/bar.bar.bar.json'),
       ]).expect({ namedParamA: 'bar.bar.bar' })
     })
@@ -83,9 +77,6 @@ describe('Route helpers', function() {
     test(namedParams, () => {
       forCases([
         given('/foo/bar.bar.bar.svg'),
-        given('/foo/bar.bar.bar.png'),
-        given('/foo/bar.bar.bar.gif'),
-        given('/foo/bar.bar.bar.jpg'),
         given('/foo/bar.bar.bar.json'),
       ]).expect({})
     })