feat: rewrite to TypeScript

BREAKING CHANGE: Flow to TypeScript migration.

.eslintrc

@@ -1,7 +1,10 @@
 {
   "extends": [
     "canonical",
-    "canonical/flowtype"
+    "canonical/typescript"
   ],
+  "parserOptions": {
+    "project": "./tsconfig.json"
+  },
   "root": true
 }

.travis.yml

@@ -1,15 +1,12 @@
 language: node_js
 node_js:
-  - node
   - 10
-env:
-  - NODE_TLS_REJECT_UNAUTHORIZED=0
 script:
   - npm run lint
   - npm run test
   - nyc --silent npm run test
   - nyc report --reporter=text-lcov | coveralls
-  - nyc check-coverage --lines 60
+  - nyc check-coverage --lines 30
 after_success:
   - NODE_ENV=production npm run build
   - semantic-release

package.json

@@ -5,47 +5,40 @@
     "url": "http://gajus.com"
   },
   "ava": {
-    "babel": {
-      "compileAsTests": [
-        "test/helpers/**/*"
-      ]
-    },
+    "extensions": [
+      "ts"
+    ],
     "files": [
       "test/http-terminator/**/*"
     ],
     "require": [
-      "@babel/register"
+      "ts-node/register/transpile-only"
     ]
   },
   "dependencies": {
-    "delay": "^4.3.0",
-    "roarr": "^2.14.6"
+    "delay": "^5.0.0",
+    "roarr": "^4.0.8",
+    "type-fest": "^0.20.2"
   },
   "description": "Gracefully terminates HTTP(S) server.",
   "devDependencies": {
-    "@ava/babel": "^1.0.0",
-    "@babel/cli": "^7.8.3",
-    "@babel/core": "^7.8.3",
-    "@babel/node": "^7.8.3",
-    "@babel/plugin-transform-flow-strip-types": "^7.8.3",
-    "@babel/preset-env": "^7.8.3",
-    "@babel/register": "^7.8.3",
-    "agentkeepalive": "^4.1.0",
-    "ava": "^3.0.0",
+    "agentkeepalive": "^4.1.4",
+    "ava": "^3.15.0",
     "babel-plugin-istanbul": "^6.0.0",
-    "babel-plugin-transform-export-default-name": "^2.0.4",
-    "coveralls": "^3.0.9",
-    "eslint": "^6.8.0",
-    "eslint-config-canonical": "^18.1.0",
-    "flow-bin": "^0.116.1",
-    "flow-copy-source": "^2.0.9",
-    "gitdown": "^3.1.2",
-    "got": "^10.2.2",
-    "husky": "^4.0.10",
-    "nyc": "^15.0.0",
-    "pem": "^1.14.3",
-    "semantic-release": "^16.0.2",
-    "sinon": "^8.1.0"
+    "babel-plugin-transform-export-default-name": "^2.1.0",
+    "coveralls": "^3.1.0",
+    "del-cli": "^3.0.1",
+    "eslint": "^7.19.0",
+    "eslint-config-canonical": "^25.8.15",
+    "gitdown": "^3.1.3",
+    "got": "^11.8.1",
+    "husky": "^4.0.0",
+    "nyc": "^15.1.0",
+    "pem": "^1.14.4",
+    "semantic-release": "^17.3.8",
+    "sinon": "^9.2.4",
+    "ts-node": "^9.1.1",
+    "typescript": "^4.1.3"
   },
   "engines": {
     "node": ">=10"
@@ -60,33 +53,18 @@
     "prometheus"
   ],
   "license": "BSD-3-Clause",
-  "main": "./dist/index.js",
+  "main": "./dist/src/index.js",
   "name": "http-terminator",
-  "nyc": {
-    "all": true,
-    "include": [
-      "src/**/*.js"
-    ],
-    "instrument": false,
-    "reporter": [
-      "html",
-      "text-summary"
-    ],
-    "require": [
-      "@babel/register"
-    ],
-    "silent": true,
-    "sourceMap": false
-  },
   "repository": {
     "type": "git",
     "url": "https://github.com/gajus/http-terminator"
   },
   "scripts": {
-    "build": "rm -fr ./dist && NODE_ENV=production babel ./src --out-dir ./dist --copy-files --source-maps && flow-copy-source src dist",
+    "build": "del-cli ./dist && tsc",
     "generate-readme": "gitdown ./.README/README.md --output-file ./README.md",
-    "lint": "eslint ./src ./test && flow",
-    "test": "NODE_ENV=test ava --verbose --serial"
+    "lint": "eslint ./src ./test && tsc --noEmit",
+    "test": "NODE_ENV=test ava --serial --verbose"
   },
+  "typings": "./dist/src/index.d.ts",
   "version": "1.0.0"
 }

src/Logger.js → src/Logger.ts

@@ -1,5 +1,3 @@
-// @flow
-
 import Roarr from 'roarr';
 
 export default Roarr.child({

src/factories/createHttpTerminator.js → src/factories/createHttpTerminator.ts

@@ -1,12 +1,12 @@
-// @flow
-
 import type {
-  HttpTerminatorType,
-  HttpTerminatorConfigurationInputType,
+  HttpTerminator,
+  HttpTerminatorConfigurationInput,
 } from '../types';
 import createInternalHttpTerminator from './createInternalHttpTerminator';
 
-export default (configurationInput: HttpTerminatorConfigurationInputType): HttpTerminatorType => {
+export default (
+  configurationInput: HttpTerminatorConfigurationInput,
+): HttpTerminator => {
   const httpTerminator = createInternalHttpTerminator(configurationInput);
 
   return {

src/factories/createInternalHttpTerminator.js → src/factories/createInternalHttpTerminator.ts

@@ -1,31 +1,37 @@
-// @flow
-
 import http from 'http';
+import type {
+  Socket,
+} from 'net';
+import type {
+  TLSSocket,
+} from 'tls';
 import delay from 'delay';
+import Logger from '../Logger';
 import type {
-  HttpTerminatorConfigurationInputType,
-  InternalHttpTerminatorType,
+  HttpTerminatorConfigurationInput,
+  InternalHttpTerminator,
 } from '../types';
-import Logger from '../Logger';
 
 const log = Logger.child({
   namespace: 'createHttpTerminator',
 });
 
 const configurationDefaults = {
-  gracefulTerminationTimeout: 1000,
+  gracefulTerminationTimeout: 1_000,
 };
 
-export default (configurationInput: HttpTerminatorConfigurationInputType): InternalHttpTerminatorType => {
+export default (
+  configurationInput: HttpTerminatorConfigurationInput,
+): InternalHttpTerminator => {
   const configuration = {
     ...configurationDefaults,
     ...configurationInput,
   };
 
   const server = configuration.server;
 
-  const sockets = new Set();
-  const secureSockets = new Set();
+  const sockets = new Set<Socket>();
+  const secureSockets = new Set<TLSSocket>();
 
   let terminating;
 
@@ -87,11 +93,12 @@ export default (configurationInput: HttpTerminatorConfigurationInputType): Inter
 
     for (const socket of sockets) {
       // This is the HTTP CONNECT request socket.
+      // @ts-expect-error Unclear if I am using wrong type or how else this should be handled.
       if (!(socket.server instanceof http.Server)) {
         continue;
       }
 
-      // $FlowFixMe
+      // @ts-expect-error Unclear if I am using wrong type or how else this should be handled.
       const serverResponse = socket._httpMessage;
 
       if (serverResponse) {
@@ -106,7 +113,7 @@ export default (configurationInput: HttpTerminatorConfigurationInputType): Inter
     }
 
     for (const socket of secureSockets) {
-      // $FlowFixMe
+      // @ts-expect-error Unclear if I am using wrong type or how else this should be handled.
       const serverResponse = socket._httpMessage;
 
       if (serverResponse) {

src/index.ts

@@ -0,0 +1,6 @@
+export {
+  default as createHttpTerminator,
+} from './factories/createHttpTerminator';
+export type {
+  HttpTerminator,
+} from './types';

src/types.ts

@@ -0,0 +1,33 @@
+import type {
+  Server as HttpServer,
+} from 'http';
+import type {
+  Server as HttpsServer,
+} from 'https';
+import type {
+  Socket,
+} from 'net';
+import type {
+  Merge,
+} from 'type-fest';
+
+/**
+ * @property gracefulTerminationTimeout Number of milliseconds to allow for the active sockets to complete serving the response (default: 5000).
+ * @property server Instance of http.Server.
+ */
+export type HttpTerminatorConfigurationInput = {
+  readonly gracefulTerminationTimeout?: number,
+  readonly server: HttpServer | HttpsServer,
+};
+
+/**
+ * @property terminate Terminates HTTP server.
+ */
+export type HttpTerminator = {
+  readonly terminate: () => Promise<void>,
+};
+
+export type InternalHttpTerminator = Merge<HttpTerminator, {
+  readonly secureSockets: Set<Socket>,
+  readonly sockets: Set<Socket>,
+}>;

test/helpers/createHttpServer.js → test/helpers/createHttpServer.ts

@@ -1,28 +1,30 @@
-// @flow
-
-import {
-  createServer,
+import type {
   Server,
   IncomingMessage as HttpIncomingMessage,
   ServerResponse as HttpServerResponse,
 } from 'http';
+import {
+  createServer,
+} from 'http';
 import {
   promisify,
 } from 'util';
 
-type RequestHandlerType = (incomingMessage: HttpIncomingMessage, outgoingMessage: HttpServerResponse) => void;
+type RequestHandler = (incomingMessage: HttpIncomingMessage, outgoingMessage: HttpServerResponse) => void;
 
-type HttpServerType = {|
-  +getConnections: () => Promise<number>,
-  +port: number,
-  +server: Server,
-  +stop: () => Promise<void>,
-  +url: string,
-|};
+type HttpServerType = {
+  readonly getConnections: () => Promise<number>,
+  readonly port: number,
+  readonly server: Server,
+  readonly stop: () => Promise<void>,
+  readonly url: string,
+};
 
-export type HttpServerFactoryType = (requestHandler: RequestHandlerType) => Promise<HttpServerType>;
+export type HttpServerFactory = (requestHandler: RequestHandler) => Promise<HttpServerType>;
 
-export default (requestHandler: RequestHandlerType): Promise<HttpServerType> => {
+export default (
+  requestHandler: RequestHandler,
+): Promise<HttpServerType> => {
   const server = createServer(requestHandler);
 
   let serverShutingDown;
@@ -45,6 +47,7 @@ export default (requestHandler: RequestHandlerType): Promise<HttpServerType> =>
     server.once('error', reject);
 
     server.listen(() => {
+      // @ts-expect-error-error address should be always available inside the `.listen()` block.
       const port = server.address().port;
       const url = 'http://localhost:' + port;