feat: read env with default value

.eslintrc

@@ -0,0 +1,6 @@
+{
+  "extends": [
+    "eslint-config-egg/typescript",
+    "eslint-config-egg/lib/rules/enforce-node-prefix"
+  ]
+}

.github/workflows/ci.yml

@@ -0,0 +1,17 @@
+name: CI
+
+on:
+  push:
+    branches: [ master ]
+  pull_request:
+    branches: [ master ]
+
+jobs:
+  Job:
+    name: Node.js
+    uses: node-modules/github-actions/.github/workflows/node-test.yml@master
+    with:
+      os: 'ubuntu-latest, macos-latest, windows-latest'
+      version: '20, 22'
+    secrets:
+      CODECOV_TOKEN: ${{ secrets.CODECOV_TOKEN }}

.github/workflows/pkg.pr.new.yml

@@ -0,0 +1,23 @@
+name: Publish Any Commit
+on: [push, pull_request]
+
+jobs:
+  build:
+    runs-on: ubuntu-latest
+
+    steps:
+      - name: Checkout code
+        uses: actions/checkout@v4
+
+      - run: corepack enable
+      - uses: actions/setup-node@v4
+        with:
+          node-version: 20
+
+      - name: Install dependencies
+        run: npm install
+
+      - name: Build
+        run: npm run prepublishOnly --if-present
+
+      - run: npx pkg-pr-new publish

.github/workflows/release.yml

@@ -0,0 +1,13 @@
+name: Release
+
+on:
+  push:
+    branches: [ master ]
+
+jobs:
+  release:
+    name: Node.js
+    uses: node-modules/github-actions/.github/workflows/node-release.yml@master
+    secrets:
+      NPM_TOKEN: ${{ secrets.NPM_TOKEN }}
+      GIT_TOKEN: ${{ secrets.GIT_TOKEN }}

.gitignore

@@ -128,3 +128,4 @@ dist
 .yarn/build-state.yml
 .yarn/install-state.gz
 .pnp.*
+.tshy

LICENSE

@@ -1,6 +1,6 @@
 MIT License
 
-Copyright (c) 2025 node_modules
+Copyright(c) 2025 - present node-modules and the contributors.
 
 Permission is hereby granted, free of charge, to any person obtaining a copy
 of this software and associated documentation files (the "Software"), to deal

README.md

@@ -1,2 +1,50 @@
 # read-env-value
+
+[![NPM Version](https://img.shields.io/npm/v/read-env-value)](https://www.npmjs.com/package/read-env-value)
+[![NPM Downloads](https://img.shields.io/npm/dm/read-env-value)](https://www.npmjs.com/package/read-env-value)
+[![NPM License](https://img.shields.io/npm/l/read-env-value)](https://github.com/node-modules/read-env-value/blob/master/LICENSE)
+[![codecov](https://codecov.io/gh/node-modules/read-env-value/branch/master/graph/badge.svg)](https://codecov.io/gh/node-modules/read-env-value)
+[![GitHub Workflow Status](https://img.shields.io/github/actions/workflow/status/node-modules/read-env-value/ci.yml?branch=master)](https://github.com/node-modules/read-env-value/actions/workflows/ci.yml?query=branch%3Amaster)
+
 Read env with default value
+
+## Usage
+
+```ts
+import { env } from 'read-env-value';
+
+// read env 'NODE_ENV' with default value 'development'
+const value = env('NODE_ENV', 'string', 'development');
+```
+
+## API
+
+### env(key: string, type: 'string' | 'number' | 'boolean', defaultValue?: string | number | boolean)
+
+#### Parameters
+
+- `key`: The environment variable key to read.
+- `type`: The type of the value to be returned.
+- `defaultValue`: The default value to return if the environment variable is not set.
+
+#### Returns
+
+- The value of the environment variable.
+
+#### Example
+
+```ts
+import { env } from 'read-env-value';
+
+const value = env('NODE_ENV', 'string', 'development');
+```
+
+## License
+
+[MIT](./LICENSE)
+
+## Contributors
+
+[![Contributors](https://contrib.rocks/image?repo=node-modules/read-env-value)](https://github.com/node-modules/read-env-value/graphs/contributors)
+
+Made with [contributors-img](https://contrib.rocks).

package.json

@@ -0,0 +1,72 @@
+{
+  "name": "read-env-value",
+  "version": "1.0.0",
+  "description": "Read env with default value",
+  "repository": {
+    "type": "git",
+    "url": "git+ssh://[email protected]/node-modules/read-env-value.git"
+  },
+  "keywords": [
+    "env",
+    "environment"
+  ],
+  "author": "fengmk2",
+  "license": "MIT",
+  "bugs": {
+    "url": "https://github.com/node-modules/read-env-value/issues"
+  },
+  "homepage": "https://github.com/node-modules/read-env-value#readme",
+  "engines": {
+    "node": ">= 20.0.0"
+  },
+  "devDependencies": {
+    "@arethetypeswrong/cli": "^0.17.3",
+    "@eggjs/tsconfig": "1",
+    "@types/mocha": "10",
+    "@types/node": "22",
+    "@vitest/coverage-v8": "^3.0.5",
+    "eslint": "8",
+    "eslint-config-egg": "14",
+    "mm": "^4.0.2",
+    "tshy": "3",
+    "tshy-after": "1",
+    "typescript": "5",
+    "vitest": "^3.0.5"
+  },
+  "scripts": {
+    "lint": "eslint --cache src test --ext .ts",
+    "pretest": "npm run lint -- --fix",
+    "test": "vitest",
+    "preci": "npm run lint",
+    "ci": "vitest run --coverage",
+    "postci": "npm run prepublishOnly",
+    "prepublishOnly": "tshy && tshy-after && attw --pack"
+  },
+  "type": "module",
+  "tshy": {
+    "exports": {
+      ".": "./src/index.ts",
+      "./package.json": "./package.json"
+    }
+  },
+  "exports": {
+    ".": {
+      "import": {
+        "types": "./dist/esm/index.d.ts",
+        "default": "./dist/esm/index.js"
+      },
+      "require": {
+        "types": "./dist/commonjs/index.d.ts",
+        "default": "./dist/commonjs/index.js"
+      }
+    },
+    "./package.json": "./package.json"
+  },
+  "files": [
+    "dist",
+    "src"
+  ],
+  "types": "./dist/commonjs/index.d.ts",
+  "main": "./dist/commonjs/index.js",
+  "module": "./dist/esm/index.js"
+}

src/index.ts

@@ -0,0 +1,46 @@
+export type ValueType = 'string' | 'boolean' | 'number';
+export type DefaultValue = string | boolean | number | undefined;
+
+type TypeMap<D> = {
+  'string': D extends undefined ? string | undefined : string;
+  'boolean': D extends undefined ? boolean | undefined : boolean;
+  'number': D extends undefined ? number | undefined : number;
+};
+
+type EnvReturn<V extends ValueType, D extends DefaultValue> = TypeMap<D>[V];
+
+export function env<V extends ValueType, D extends DefaultValue>(key: string, valueType: V, defaultValue?: D): EnvReturn<V, D> {
+  let value = process.env[key];
+  if (typeof value === 'string') {
+    value = value.trim();
+  }
+  if (!value) {
+    return defaultValue as EnvReturn<V, D>;
+  }
+
+  if (valueType === 'string') {
+    return value as EnvReturn<V, D>;
+  }
+
+  if (valueType === 'boolean') {
+    let booleanValue = false;
+    if (value === 'true' || value === '1') {
+      booleanValue = true;
+    } else if (value === 'false' || value === '0') {
+      booleanValue = false;
+    } else {
+      throw new TypeError(`Invalid boolean value: ${value} on process.env.${key}`);
+    }
+    return booleanValue as EnvReturn<V, D>;
+  }
+
+  if (valueType === 'number') {
+    const numberValue = Number(value);
+    if (isNaN(numberValue)) {
+      throw new TypeError(`Invalid number value: ${value} on process.env.${key}`);
+    }
+    return numberValue as EnvReturn<V, D>;
+  }
+
+  throw new TypeError(`Invalid value type: ${valueType}`);
+}

test/index.test.ts

@@ -0,0 +1,101 @@
+import assert from 'node:assert/strict';
+import { test, beforeEach } from 'vitest';
+import { mock, restore } from 'mm';
+import { env } from '../src/index.js';
+
+beforeEach(restore);
+
+test('should return default value if env is not set', () => {
+  assert.equal(env('TEST_ENV_STRING', 'string', 'default'), 'default');
+  assert.equal(env('TEST_ENV_BOOLEAN', 'boolean', false), false);
+  assert.equal(env('TEST_ENV_NUMBER', 'number', 0), 0);
+});
+
+test('should return undefined if env is not set', () => {
+  assert.equal(env('TEST_ENV_STRING', 'string'), undefined);
+  assert.equal(env('TEST_ENV_BOOLEAN', 'boolean'), undefined);
+  assert.equal(env('TEST_ENV_NUMBER', 'number'), undefined);
+
+  assert.equal(env('TEST_ENV_STRING', 'string') ?? null, null);
+  assert.equal(env('TEST_ENV_NUMBER', 'number') ?? 0, 0);
+  assert.equal(env('TEST_ENV_BOOLEAN', 'boolean') ?? false, false);
+  assert.equal(env('TEST_ENV_STRING', 'string') ?? 'default', 'default');
+});
+
+test('should return env value if env is set to empty string', () => {
+  mock(process.env, 'TEST_ENV_STRING', '');
+  mock(process.env, 'TEST_ENV_BOOLEAN', '');
+  mock(process.env, 'TEST_ENV_NUMBER', '');
+
+  assert.equal(env('TEST_ENV_STRING', 'string', ''), '');
+  assert.equal(env('TEST_ENV_STRING', 'string'), undefined);
+  assert.equal(env('TEST_ENV_STRING', 'string', 'default string'), 'default string');
+  assert.equal(env('TEST_ENV_BOOLEAN', 'boolean', true), true);
+  assert.equal(env('TEST_ENV_BOOLEAN', 'boolean', false), false);
+  assert.equal(env('TEST_ENV_NUMBER', 'number', 3306), 3306);
+  assert.equal(env('TEST_ENV_NUMBER', 'number', 0), 0);
+  assert.equal(env('TEST_ENV_NUMBER', 'number', -123), -123);
+
+  mock(process.env, 'TEST_ENV_STRING', '    ');
+  mock(process.env, 'TEST_ENV_BOOLEAN', '  \t  ');
+  mock(process.env, 'TEST_ENV_NUMBER', '   \t\t\t  ');
+
+  assert.equal(env('TEST_ENV_STRING', 'string', ''), '');
+  assert.equal(env('TEST_ENV_STRING', 'string', 'default string'), 'default string');
+  assert.equal(env('TEST_ENV_BOOLEAN', 'boolean', true), true);
+  assert.equal(env('TEST_ENV_BOOLEAN', 'boolean', false), false);
+  assert.equal(env('TEST_ENV_NUMBER', 'number', 3306), 3306);
+  assert.equal(env('TEST_ENV_NUMBER', 'number', 0), 0);
+});
+
+test('should throw error if env is set to invalid value', () => {
+  mock(process.env, 'TEST_ENV_BOOLEAN', 'invalid');
+  assert.throws(() => env('TEST_ENV_BOOLEAN', 'boolean', false), /Invalid boolean value: invalid on process.env.TEST_ENV_BOOLEAN/);
+
+  mock(process.env, 'TEST_ENV_NUMBER', 'invalid');
+  assert.throws(() => env('TEST_ENV_NUMBER', 'number', 0), /Invalid number value: invalid on process.env.TEST_ENV_NUMBER/);
+
+  mock(process.env, 'TEST_ENV_NUMBER', 'abc');
+  assert.throws(() => env('TEST_ENV_NUMBER', 'number', 0), /Invalid number value: abc on process.env.TEST_ENV_NUMBER/);
+});
+
+test('should throw error if value type is invalid', () => {
+  mock(process.env, 'TEST_ENV_STRING', '123');
+  assert.throws(() => (env as any)('TEST_ENV_STRING', 'float', 'default'), /Invalid value type: float/);
+});
+
+test('should work with string value', () => {
+  mock(process.env, 'TEST_ENV_STRING', 'http://localhost:3000');
+  assert.equal(env('TEST_ENV_STRING', 'string', 'default'), 'http://localhost:3000');
+
+  mock(process.env, 'TEST_ENV_STRING', '      ');
+  assert.equal(env('TEST_ENV_STRING', 'string', 'default'), 'default');
+});
+
+test('should work with boolean value', () => {
+  mock(process.env, 'TEST_ENV_BOOLEAN', 'true');
+  assert.equal(env('TEST_ENV_BOOLEAN', 'boolean', false), true);
+
+  mock(process.env, 'TEST_ENV_BOOLEAN', 'false');
+  assert.equal(env('TEST_ENV_BOOLEAN', 'boolean', true), false);
+
+  mock(process.env, 'TEST_ENV_BOOLEAN', '1');
+  assert.equal(env('TEST_ENV_BOOLEAN', 'boolean', false), true);
+
+  mock(process.env, 'TEST_ENV_BOOLEAN', '0');
+  assert.equal(env('TEST_ENV_BOOLEAN', 'boolean', true), false);
+});
+
+test('should work with number value', () => {
+  mock(process.env, 'TEST_ENV_NUMBER', '123');
+  assert.equal(env('TEST_ENV_NUMBER', 'number', 0), 123);
+
+  mock(process.env, 'TEST_ENV_NUMBER', '-123');
+  assert.equal(env('TEST_ENV_NUMBER', 'number', 0), -123);
+
+  mock(process.env, 'TEST_ENV_NUMBER', '123.456');
+  assert.equal(env('TEST_ENV_NUMBER', 'number', 0), 123.456);
+
+  mock(process.env, 'TEST_ENV_NUMBER', '0');
+  assert.equal(env('TEST_ENV_NUMBER', 'number', 10), 0);
+});

tsconfig.json

@@ -0,0 +1,10 @@
+{
+  "extends": "@eggjs/tsconfig",
+  "compilerOptions": {
+    "strict": true,
+    "noImplicitAny": true,
+    "target": "ES2022",
+    "module": "NodeNext",
+    "moduleResolution": "NodeNext"
+  }
+}