Typescript migration changes for obj-multiplex

.circleci/config.yml

@@ -0,0 +1,66 @@
+version: 2.1
+
+workflows:
+  build-test:
+    jobs:
+      - prep-deps
+      - test-build:
+          requires:
+            - prep-deps
+      - test-lint:
+          requires:
+            - prep-deps
+      - all-tests-pass:
+          requires:
+            - test-build
+            - test-lint
+
+jobs:
+  prep-deps:
+    docker:
+      - image: circleci/node:10
+    steps:
+      - checkout
+      - run:
+          name: Install deps
+          command: |
+            .circleci/scripts/deps-install.sh
+      - run:
+          name: Collect yarn install HAR logs
+          command: |
+            .circleci/scripts/collect-har-artifact.sh
+      - persist_to_workspace:
+          root: .
+          paths:
+          - node_modules
+          - build-artifacts
+
+  test-build:
+    docker:
+      - image: circleci/node:10
+    steps:
+      - checkout
+      - attach_workspace:
+          at: .
+      - run:
+          name: Build project
+          command: yarn build
+
+  test-lint:
+    docker:
+      - image: circleci/node:10
+    steps:
+      - checkout
+      - attach_workspace:
+          at: .
+      - run:
+          name: Lint
+          command: yarn lint
+
+  all-tests-pass:
+    docker:
+      - image: circleci/node:10
+    steps:
+      - run:
+          name: All tests passed
+          command: echo 'Great success'

.circleci/scripts/collect-har-artifact.sh

@@ -0,0 +1,9 @@
+#!/usr/bin/env bash
+
+set -x
+set -e
+set -u
+set -o pipefail
+
+mkdir -p build-artifacts/yarn-install-har
+mv ./*.har build-artifacts/yarn-install-har/

.circleci/scripts/deps-install.sh

@@ -0,0 +1,8 @@
+#!/usr/bin/env bash
+
+set -x
+set -e
+set -u
+set -o pipefail
+
+yarn --frozen-lockfile --ignore-scripts --har

.eslintrc.js

@@ -0,0 +1,32 @@
+module.exports = {
+  root: true,
+  parserOptions: {
+    ecmaVersion: 2017,
+  },
+  extends: [
+    '@metamask/eslint-config',
+    '@metamask/eslint-config/config/nodejs',
+    '@metamask/eslint-config/config/typescript',
+  ],
+  plugins: [
+    'json',
+  ],
+  overrides: [{
+    files: [
+      '*.js',
+      '*.json',
+    ],
+    parserOptions: {
+      sourceType: 'script',
+    },
+    rules: {
+      '@typescript-eslint/no-require-imports': 'off',
+      '@typescript-eslint/no-var-requires': 'off',
+    },
+  }],
+  ignorePatterns: [
+    '!eslintrc.js',
+    'dist/',
+    'node_modules/',
+  ],
+};

.gitignore

@@ -43,6 +43,12 @@ jspm_packages/
 # Typescript v1 declaration files
 typings/
 
+# Typscript build / generate output
+dist/ 
+
+# package-lock generated by npm
+package-lock.json
+
 # Optional npm cache directory
 .npm
 
@@ -68,7 +74,7 @@ typings/
 .LSOverride
 
 # Icon must end with two \r
-Icon
+Icon
 
 # Thumbnails
 ._*

package.json

@@ -2,19 +2,34 @@
   "name": "obj-multiplex",
   "version": "1.0.2",
   "description": "",
-  "main": "index.js",
+  "main": "dist/index.js",
   "scripts": {
-    "test": "node test"
+    "build": "tsc --project .",
+    "lint": "eslint . --ext ts,js,json",
+    "lint:fix": "yarn lint --fix",
+    "test": "yarn build && node test"
   },
   "author": "",
   "license": "ISC",
   "dependencies": {
-    "end-of-stream": "^1.4.0",
+    "end-of-stream": "^1.4.4",
     "once": "^1.4.0",
     "readable-stream": "^2.3.3"
   },
   "devDependencies": {
+    "@metamask/eslint-config": "^4.1.0",
+    "@types/end-of-stream": "^1.4.0",
+    "@types/node": "^14.14.9",
+    "@types/once": "^1.4.0",
+    "@types/readable-stream": "^2.3.9",
+    "@typescript-eslint/eslint-plugin": "^4.8.2",
+    "@typescript-eslint/parser": "^4.8.2",
+    "eslint": "^7.14.0",
+    "eslint-plugin-import": "^2.22.1",
+    "eslint-plugin-json": "^2.1.2",
+    "eslint-plugin-node": "^11.1.0",
     "pump": "^1.0.2",
-    "tape": "^4.8.0"
+    "tape": "^4.8.0",
+    "typescript": "^4.1.2"
   }
 }

src/ObjectMultiplex.ts

@@ -0,0 +1,93 @@
+import { Duplex } from 'readable-stream';
+import eos from 'end-of-stream';
+import once from 'once';
+import { Substream } from './Substream';
+
+const IGNORE_SUBSTREAM: Record<string, unknown> = {};
+
+export class ObjectMultiplex extends Duplex {
+
+  private _substreams: Record<string, Substream | Record<string, any>>;
+
+  constructor(_opts: Record<string, unknown> = {}) {
+    const opts = Object.assign({}, _opts, {
+      objectMode: true,
+    });
+    super(opts);
+    this._substreams = {};
+  }
+
+  createStream(name: string): Substream {
+    // validate name
+    if (!name) {
+      throw new Error('ObjectMultiplex - name must not be empty');
+    }
+
+    if (this._substreams[name]) {
+      throw new Error(`ObjectMultiplex - Substream for name "${name}" already exists`);
+    }
+
+    // create substream
+    const substream = new Substream({ parent: this, name });
+    this._substreams[name] = substream;
+
+    // listen for parent stream to end
+    anyStreamEnd(this, (_error?: Error | null) => {
+      substream.destroy();
+    });
+
+    return substream;
+  }
+
+  // ignore streams (dont display orphaned data warning)
+  ignoreStream(name: string): void {
+    // validate name
+    if (!name) {
+      throw new Error('ObjectMultiplex - name must not be empty');
+    }
+    if (this._substreams[name]) {
+      throw new Error(`ObjectMultiplex - Substream for name "${name}" already exists`);
+    }
+    // set
+    this._substreams[name] = IGNORE_SUBSTREAM;
+  }
+
+  _read(): void {
+    return undefined;
+  }
+
+  _write(
+    chunk: Record<string, any>,
+    _encoding: BufferEncoding,
+    callback: (error?: Error | null) => void,
+  ): void {
+
+    const { name, data } = chunk;
+
+    if (!name) {
+      console.warn(`ObjectMultiplex - malformed chunk without name "${chunk}"`);
+      return callback();
+    }
+
+    // get corresponding substream
+    const substream = this._substreams[name];
+    if (!substream) {
+      console.warn(`ObjectMultiplex - orphaned data for stream "${name}"`);
+      return callback();
+    }
+
+    // push data into substream
+    if (substream !== IGNORE_SUBSTREAM) {
+      substream.push(data);
+    }
+
+    return callback();
+  }
+}
+
+// util
+function anyStreamEnd(stream: ObjectMultiplex, _cb: (error?: Error | null) => void) {
+  const cb = once(_cb);
+  eos(stream, { readable: false }, cb);
+  eos(stream, { writable: false }, cb);
+}