Merge pull request #1 from fingerprintjs/feature/agent-js-proxy

JS agent proxy

.github/workflows/coverage-diff.yml

@@ -0,0 +1,31 @@
+name: Check coverage for PR
+
+on:
+  pull_request:
+
+jobs:
+  run-tests-check-coverage:
+    runs-on: ubuntu-20.04
+    name: Run tests & check coverage
+    steps:
+      - uses: actions/checkout@v3
+      - name: Jest coverage comment
+        id: coverage
+        uses: ArtiomTr/jest-coverage-report-action@9f733792c44d05327cb371766bf78a5261e43936
+        with:
+          package-manager: yarn
+          output: report-markdown
+      - name: Read coverage text report
+        uses: fingerprintjs/action-coverage-report-md@v1
+        id: coverage-md
+        with:
+          srcBasePath: './'
+      - uses: marocchino/sticky-pull-request-comment@adca94abcaf73c10466a71cc83ae561fd66d1a56
+        with:
+          message: |
+            ${{ steps.coverage.outputs.report }}
+            <details>
+              <summary>Show full coverage report</summary>
+
+              ${{ steps.coverage-md.outputs.markdownReport }}
+            </details>

.github/workflows/coverage-report.yml

@@ -0,0 +1,46 @@
+name: Coverage
+
+on:
+  push:
+    branches:
+      - main
+
+jobs:
+  build-and-run-tests:
+    runs-on: ubuntu-20.04
+    name: Build & run tests & publish coverage
+    steps:
+      - uses: actions/checkout@v3
+
+      - name: Install node
+        uses: actions/setup-node@v3
+        with:
+          node-version-file: '.node-version'
+      - name: Get yarn cache directory path
+        id: yarn-cache-dir-path
+        run: echo "dir=$(yarn cache dir)" >> $GITHUB_OUTPUT
+      - uses: actions/cache@v3
+        id: yarn-cache # use this to check for `cache-hit` (`steps.yarn-cache.outputs.cache-hit != 'true'`)
+        with:
+          path: ${{ steps.yarn-cache-dir-path.outputs.dir }}
+          key: ${{ runner.os }}-yarn-${{ hashFiles('**/yarn.lock') }}
+          restore-keys: |
+            ${{ runner.os }}-yarn-
+      - name: Install Dependencies and prepare packages
+        run: yarn install
+        env:
+          CI: true
+      - name: Run test
+        run: yarn test
+
+      - name: Create Coverage Badges
+        uses: jaywcjlove/coverage-badges-cli@e07f25709cd25486855c1ba1b26da53576ff3620
+        with:
+          source: coverage/coverage-summary.json
+          output: coverage/lcov-report/badges.svg
+
+      - name: Deploy
+        uses: JamesIves/github-pages-deploy-action@8817a56e5bfec6e2b08345c81f4d422db53a2cdc
+        with:
+          branch: gh-pages
+          folder: ./coverage/lcov-report/

.gitignore

@@ -69,7 +69,7 @@ typings/
 .yarn-integrity
 
 # dotenv environment variables file
-.env.test
+.env
 
 # parcel-bundler cache (https://parceljs.org/)
 .cache

jest.config.js

@@ -2,8 +2,16 @@
 module.exports = {
   preset: 'ts-jest',
   testEnvironment: 'node',
-  testRegex: '/functions/.+test.tsx?$',
+  testRegex: '/proxy/.+test.tsx?$',
   passWithNoTests: true,
-  collectCoverageFrom: ['./functions/**/**.ts', '!**/index.ts'],
+  collectCoverageFrom: ['./proxy/**/**.ts', '!**/index.ts', '!**/config.ts', './management/**/**.ts'],
   coverageReporters: ['lcov', 'json-summary', ['text', { file: 'coverage.txt', path: './' }]],
+  transform: {
+    '^.+\\.[tj]sx?$': [
+      'ts-jest',
+      {
+        tsconfig: '<rootDir>/tsconfig.test.json',
+      },
+    ],
+  },
 }

package.json

@@ -9,7 +9,7 @@
     "lint": "eslint --ext .js,.ts --ignore-path .gitignore --max-warnings 0 .",
     "lint:fix": "yarn lint --fix",
     "test": "jest --coverage",
-    "test:dts": "tsc --noEmit --isolatedModules dist/*.d.ts",
+    "test:dts": "tsc --noEmit --isolatedModules dist/**/*.d.ts",
     "emulate-storage": "azurite -l ./storage --silent",
     "start": "func start"
   },
@@ -31,6 +31,7 @@
     "@rollup/plugin-json": "^4.1.0",
     "@rollup/plugin-node-resolve": "^15.0.1",
     "@rollup/plugin-replace": "^5.0.1",
+    "@types/jest": "^29.4.1",
     "@types/node": "^16.x",
     "@typescript-eslint/eslint-plugin": "^5.44.0",
     "@typescript-eslint/parser": "^5.44.0",

proxy/agent.ts → proxy/handlers/agent.ts

@@ -1,15 +1,15 @@
-import { HttpRequest } from '@azure/functions'
-import { config } from './config'
+import { HttpRequest, Logger } from '@azure/functions'
+import { config } from '../utils/config'
 import * as https from 'https'
-import { updateResponseHeaders } from './headers'
+import { filterRequestHeaders, updateResponseHeaders } from '../utils/headers'
 import { HttpResponseSimple } from '@azure/functions/types/http'
 
-function getEndpoint(apiKey: string | undefined, version: string, loaderVersion: string | undefined): string {
-  const lv: string = loaderVersion !== undefined && loaderVersion !== '' ? `/loader_v${loaderVersion}.js` : ''
-  return `/v${version}/${apiKey}${lv}`
+export interface DownloadAgentParams {
+  httpRequest: HttpRequest
+  logger: Logger
 }
 
-export async function downloadAgent(httpRequest: HttpRequest) {
+export async function downloadAgent({ httpRequest, logger }: DownloadAgentParams) {
   const apiKey = httpRequest.query.apiKey
   const version = httpRequest.query.version
   const loaderVersion = httpRequest.query.loaderVersion
@@ -19,26 +19,17 @@ export async function downloadAgent(httpRequest: HttpRequest) {
   const url = new URL(`https://${config.fpdcdn}`)
   url.pathname = getEndpoint(apiKey, version, loaderVersion)
 
-  const headers = {
-    ...httpRequest.headers,
-  }
+  logger.verbose('Downloading agent from', url.toString())
 
-  // TODO - Extract this into separate function
-  delete headers['host']
-  delete headers['content-length']
-  delete headers['transfer-encoding']
-  delete headers['via']
+  const headers = filterRequestHeaders(httpRequest.headers)
 
-  return new Promise<HttpResponseSimple & { isRaw?: boolean }>((resolve) => {
+  return new Promise<HttpResponseSimple>((resolve) => {
     const data: any[] = []
 
-    console.debug('Downloading agent from', url.toString())
-
     const request = https.request(
       url,
       {
         method: 'GET',
-        // TODO Filter headers
         headers,
       },
       (response) => {
@@ -53,31 +44,34 @@ export async function downloadAgent(httpRequest: HttpRequest) {
 
         response.on('end', () => {
           const body = Buffer.concat(data)
+          const responseHeaders = updateResponseHeaders(response.headers, domain)
 
           resolve({
             status: response.statusCode ? response.statusCode.toString() : '500',
-            // TODO Filter headers
-            headers: updateResponseHeaders(response.headers, domain),
+            headers: responseHeaders,
             body: new Uint8Array(body),
-            isRaw: true,
           })
         })
       },
     )
 
     request.on('error', (error) => {
-      console.error('unable to download agent', { error })
+      logger.error('unable to download agent', { error })
 
       resolve({
         status: '500',
         headers: {
-          'Content-Type': 'application/json',
+          'Content-Type': 'text/plain',
         },
-        // TODO Generate error response with our integrations format
-        body: error,
+        body: 'error',
       })
     })
 
     request.end()
   })
 }
+
+function getEndpoint(apiKey: string | undefined, version: string, loaderVersion: string | undefined): string {
+  const lv: string = loaderVersion !== undefined && loaderVersion !== '' ? `/loader_v${loaderVersion}.js` : ''
+  return `/v${version}/${apiKey}${lv}`
+}

proxy/ingress.ts → proxy/handlers/ingress.ts

@@ -1,7 +1,7 @@
 import { HttpRequest } from '@azure/functions'
-import { config } from './config'
+import { config } from '../utils/config'
 import * as https from 'https'
-import { updateResponseHeaders } from './headers'
+import { updateResponseHeaders } from '../utils/headers'
 import { HttpResponseSimple } from '@azure/functions/types/http'
 
 export function handleIngress(httpRequest: HttpRequest) {

proxy/index.ts

@@ -1,13 +1,19 @@
 import { AzureFunction, Context, HttpRequest } from '@azure/functions'
-import { downloadAgent } from './agent'
-import { handleIngress } from './ingress'
+import { downloadAgent } from './handlers/agent'
+import { handleIngress } from './handlers/ingress'
 
 const httpTrigger: AzureFunction = async (context: Context, req: HttpRequest): Promise<void> => {
+  context.log.verbose('Handling request', {
+    req,
+    context,
+  })
+
   const path = req.params?.restOfPath
 
+  // TODO Resolve paths using customer variables
   switch (path) {
     case 'client': {
-      context.res = await downloadAgent(req)
+      context.res = await downloadAgent({ httpRequest: req, logger: context.log })
 
       break
     }

proxy/utils/cacheControl.test.ts

@@ -0,0 +1,15 @@
+import { updateCacheControlHeader } from './cacheControl'
+
+describe('updateCacheControlHeader', () => {
+  test('adjust max-age to lower value', () => {
+    expect(updateCacheControlHeader('public, max-age=36000, s-maxage=36000')).toBe('public, max-age=3600, s-maxage=60')
+  })
+
+  test('keep existing smaller value', () => {
+    expect(updateCacheControlHeader('public, max-age=600, s-maxage=600')).toBe('public, max-age=600, s-maxage=60')
+  })
+
+  test('add max age if not exist', () => {
+    expect(updateCacheControlHeader('no-cache')).toBe('no-cache, max-age=3600, s-maxage=60')
+  })
+})

proxy/utils/cacheControl.ts

@@ -0,0 +1,26 @@
+const CACHE_MAX_AGE = 3600
+const SHARED_CACHE_MAX_AGE = 60
+
+export function updateCacheControlHeader(headerValue: string): string {
+  let result = updateCacheControlAge(headerValue, 'max-age', CACHE_MAX_AGE)
+  result = updateCacheControlAge(result, 's-maxage', SHARED_CACHE_MAX_AGE)
+
+  return result
+}
+
+function updateCacheControlAge(headerValue: string, type: 'max-age' | 's-maxage', cacheMaxAge: number): string {
+  const cacheControlDirectives = headerValue.split(', ')
+  const maxAgeIndex = cacheControlDirectives.findIndex(
+    (directive) => directive.split('=')[0].trim().toLowerCase() === type,
+  )
+
+  if (maxAgeIndex === -1) {
+    cacheControlDirectives.push(`${type}=${cacheMaxAge}`)
+  } else {
+    const oldMaxAge = Number(cacheControlDirectives[maxAgeIndex].split('=')[1])
+    const newMaxAge = Math.min(cacheMaxAge, oldMaxAge)
+    cacheControlDirectives[maxAgeIndex] = `${type}=${newMaxAge}`
+  }
+
+  return cacheControlDirectives.join(', ')
+}

proxy/utils/config.ts

@@ -0,0 +1,4 @@
+export const config = {
+  fpdcdn: '__FPCDN__',
+  ingressApi: '__INGRESS_API__',
+}