basic functions complete

.eslintrc.json

+{
+  "plugins": [
+    "security",
+    "eslint-plugin-tsdoc",
+    "@typescript-eslint/eslint-plugin"
+  ],
+  "extends": [
+    "plugin:security/recommended",
+    "plugin:@typescript-eslint/recommended",
+    "standard-with-typescript"
+  ],
+  "parser":  "@typescript-eslint/parser",
+  "parserOptions": {
+      "project": "./tsconfig.json"
+  },
+  "rules": {
+    "tsdoc/syntax": "warn",
+    "@typescript-eslint/no-explicit-any": "off",
+    "@typescript-eslint/restrict-template-expressions": ["error", {"allowNumber": true}], 
+    "@typescript-eslint/no-var-requires": "off",
+    "security/detect-non-literal-fs-filename": "off",
+    "security/detect-object-injection": "off",
+    "security/detect-child-process": "off"
+    }
+}
\ No newline at end of file

.gitignore

+node_modules/
+coverage/
+stryker.log
+.stryer-tmp
+*.DS_Store
+dist/
+src/config.json
+.scannerwork/
+# stryker temp files
+.stryker-tmp
+ho-copy

.npmignore

+src/
+docs/
\ No newline at end of file

README.md

+# Metrics
+
+[![pipeline status](https://it-devops-01.br-edv.brnet.int/general/metrics/badges/master/pipeline.svg)](https://it-devops-01.br-edv.brnet.int/general/metrics/commits/master)
+[![coverage report](https://it-devops-01.br-edv.brnet.int/general/metrics/badges/master/coverage.svg)](https://it-devops-01.br-edv.brnet.int/general/metrics/commits/master)
+[![Quality Gate Status](https://it-devops-01.br-edv.brnet.int:8999/api/project_badges/measure?project=metrics&metric=alert_status)](https://it-devops-01.br-edv.brnet.int:8999/dashboard?id=metrics)
+
+A small express middleware to get base metrics for any node.js app.
+
+
+## Installation
+
+- `npm config set @br:registry https://npm.br-edv.brnet.int`
+- `npm install --save @br/metrics`
+
+## Usage
+
+`import { Metrics } from '@br/metrics'`  
+`let metrics = new Metrics(options)`
+
+Note: The options Part may be omitted, as all parts are optional.
+
+Before your Routes:
+`router.use(metrics.start.bind(metrics))`
+
+And to enable the *_metrics*-Endpoint:
+`router.get('/_metrics', metrics.endpoint)`
+
+### Options
+
+TODO: fill options
\ No newline at end of file

TODO.md

+# TODO
+
+- config
+
+- tests
+
+- README: options, examples
\ No newline at end of file

examples/src/app.ts

+'use strict'
+
+import * as http from 'http'
+import * as express from 'express'
+
+import { Metrics } from '../../dist/index'
+
+class App {
+  public app: express.Application
+  private readonly router: express.Router
+  public readonly server: http.Server
+  private readonly metrics: Metrics
+
+  constructor (port: number) {
+
+    this.app = express()
+
+    this.router = express.Router()
+
+    this.metrics = new Metrics({})
+
+    this.router.use(this.metrics.start.bind(this.metrics))
+
+    this.router.get('/favicon.ico', (req, res) => res.status(204)) // No Favicon here
+
+    this.router.get('/foo', (req:express.Request, res:express.Response) => {
+      res.status(200).send('foo')
+    })
+    this.router.get('/bar', (req:express.Request, res:express.Response) => {
+      res.status(200).send('bar')
+    })
+    this.router.get('/404', (req:express.Request, res:express.Response) => {
+      res.status(404).end()
+    })
+    this.router.get('/401', (req:express.Request, res:express.Response) => {
+      res.status(401).end()
+    })
+    this.router.get('/_metrics', this.metrics.endpoint)
+
+    this.app.use(this.router)
+
+    this.server = http.createServer(this.app)
+    this.server.listen(port)
+    console.log(`metrics-example is running on Port ${port as number}`)
+  }
+}
+export default App

examples/src/server.ts

+import App from './app'
+
+let app
+
+app = new App(parseInt(process.argv[2]))
+
+
+console.log(`metrics-example running on Port ${process.argv[2]}`)

jest.config.js

+module.exports = {
+  roots: ['<rootDir>/src/'],
+  preset: 'ts-jest',
+  testEnvironment: 'node',
+  transform: {
+    '^.+\\.tsx?$': 'ts-jest'
+  },
+  moduleFileExtensions: ['ts', 'tsx', 'js', 'jsx', 'json', 'node'],
+  collectCoverage: true,
+  coverageReporters: ['json', 'lcov', 'text', 'clover', 'html'],
+  coverageDirectory: 'docs/coverage',
+  reporters: [
+    'default',
+    ['jest-html-reporters', {
+      publicPath: './docs',
+      filename: 'test-report.html',
+      pageTitle: 'BePo Backend :: Test Results'
+    }]
+  ]
+}

package.json

+{
+  "name": "@br/metrics",
+  "version": "1.0.0",
+  "description": "A small express middleware to get base metrics for any node.js app",
+  "main": "dist/index.js",
+  "types": "dist/index.d.ts",
+  "scripts": {
+    "test": "jest",
+    "test:mutation": "stryker run",
+    "lint": "eslint src/**/*.ts",
+    "lint:fix": "eslint --fix src/**/*.ts",
+    "sast": "sonar-scanner -Dsonar.projectKey=metrics -Dsonar.sources=src/ -Dsonar.host.url=http://it-devops-01.br-edv.brnet.int:9000 -Dsonar.login=0f940d3f0fc8f7d80aeb3e1ebde7232913a818d3",
+    "check": "npm audit && npm outdated",
+    "build": "tsc",
+    "build:examples": "tsc --project tsconfig-examples.json"
+  },
+  "keywords": [
+    "metrics",
+    "prometheus"
+  ],
+  "author": "Dominik Sigmund <dominik.sigmund@br.de>",
+  "license": "Unlicense",
+  "dependencies": {
+    "express": "^4.17.1",
+    "prom-client": "^12.0.0"
+  },
+  "devDependencies": {
+    "@stryker-mutator/core": "^3.1.0",
+    "@stryker-mutator/jest-runner": "^3.1.0",
+    "@stryker-mutator/typescript": "^3.1.0",
+    "@types/express": "^4.17.4",
+    "@types/jest": "^25.1.4",
+    "@types/node": "^13.9.1",
+    "@types/superagent": "^4.1.7",
+    "@types/supertest": "^2.0.8",
+    "@typescript-eslint/eslint-plugin": "^2.24.0",
+    "eslint": "^6.8.0",
+    "eslint-config-standard-with-typescript": "^15.0.0",
+    "eslint-plugin-import": "^2.20.1",
+    "eslint-plugin-node": "^11.0.0",
+    "eslint-plugin-promise": "^4.2.1",
+    "eslint-plugin-security": "^1.4.0",
+    "eslint-plugin-standard": "^4.0.1",
+    "eslint-plugin-tsdoc": "^0.2.3",
+    "husky": "^4.2.3",
+    "jest": "^25.1.0",
+    "jest-html-reporters": "^1.2.1",
+    "standard": "^14.3.3",
+    "supertest": "^4.0.2",
+    "ts-jest": "^25.2.1",
+    "typescript": "^3.8.3"
+  },
+  "husky": {
+    "hooks": {
+      "pre-push": "npm run lint",
+      "post-commit": "./ho-copy"
+    }
+  }
+}

src/index.ts

+import * as express from 'express'
+import Prometheus = require('prom-client')
+
+export class Metrics {
+  private readonly _options: any
+  public readonly _httpRequestDurationMicroseconds: any
+  public readonly _numOfRequests: any
+  public readonly _numOfErrors: any
+
+  constructor (options: any) {
+    this._options = options
+    this._httpRequestDurationMicroseconds = new Prometheus.Histogram({
+      name: 'http_request_duration_ms',
+      help: 'Duration of HTTP requests in ms',
+      labelNames: ['method', 'route', 'code'],
+      buckets: [0.10, 5, 15, 50, 100, 200, 300, 400, 500]
+    })
+    this._numOfRequests = new Prometheus.Counter({
+      name: 'numOfRequests',
+      help: 'Number of requests made to a route',
+      labelNames: ['route']
+    })
+    this._numOfErrors = new Prometheus.Counter({
+      name: 'numOfErrors',
+      help: 'Number of errors',
+      labelNames: ['error']
+    })
+    // TODO: config: ignore routes, disable metrics
+  }
+
+  public start (req: express.Request, res: express.Response, next: express.NextFunction): void {
+    res.locals.startEpoch = Date.now()
+    res.on('finish', () => {
+      if (req.originalUrl !== '/_metrics' && req.originalUrl !== './favicon.ico') {
+        const responseTimeInMs = Date.now() - res.locals.startEpoch
+        this._httpRequestDurationMicroseconds
+          .labels(req.method, req.originalUrl, res.statusCode.toString())
+          .observe(responseTimeInMs)
+        this._numOfRequests.inc({ route: req.originalUrl })
+        if (res.statusCode >= 400) {
+          this._numOfErrors.inc({ error: res.statusCode })
+        }
+      }
+    })
+    next()
+  }
+
+  public endpoint (req: express.Request, res: express.Response): void {
+    res.set('Content-Type', Prometheus.register.contentType)
+    res.end(Prometheus.register.metrics())
+  }
+}
+
+export default Metrics

stryker.conf.json

+{
+  "$schema": "https://raw.githubusercontent.com/stryker-mutator/stryker/master/packages/api/schema/stryker-core.json",
+  "mutator": "typescript",
+  "packageManager": "npm",
+  "reporters": [
+    "html",
+    "clear-text",
+    "progress",
+    "dashboard"
+  ],
+  "htmlReporter": {
+    "baseDir": "docs/mutation"
+  },
+  "testRunner": "jest",
+  "transpilers": [],
+  "coverageAnalysis": "off",
+  "tsconfigFile": "tsconfig.json",
+  "mutate": [
+    "src/**/*.ts",
+    "!src/**/*.spec.ts"
+  ]
+}
\ No newline at end of file

tsconfig-examples.json

+{
+  "compilerOptions": {
+    "target":"ES6",
+    "module": "commonjs",
+    "lib": ["es2017"],
+    "strict": true,
+    "declaration": true,
+    "sourceMap": true,
+    "outDir": "./examples/dist/",
+    "rootDir": "./examples/src/",
+    "resolveJsonModule": true,
+    "watch": false
+  },
+  "exclude": [
+    "node_modules",
+    "./examples/dist/",
+    "./src",
+    "./dist"
+  ]
+}
\ No newline at end of file

tsconfig.json

+{
+  "compilerOptions": {
+    "target":"ES6",
+    "module": "commonjs",
+    "lib": ["es2017"],
+    "strict": true,
+    "declaration": true,
+    "sourceMap": true,
+    "outDir": "./dist/",
+    "rootDir": "./src/",
+    "resolveJsonModule": true,
+    "watch": false
+  },
+  "exclude": [
+    "node_modules",
+    "./dist/",
+    "./examples"
+  ]
+}
\ No newline at end of file