Node.js中URL模塊詳解

Node.js 中 URL 模塊全部 API 詳解

1. URL 類

const { URL } = require('url');// 1. 創建 URL 對象
const url = new URL('https://www.example.com:8080/path?query=value#hash');// 2. URL 屬性
console.log('協議:', url.protocol);      // 'https:'
console.log('主機名:', url.hostname);    // 'www.example.com'
console.log('端口:', url.port);          // '8080'
console.log('主機:', url.host);          // 'www.example.com:8080'
console.log('路徑:', url.pathname);      // '/path'
console.log('查詢字符串:', url.search);   // '?query=value'
console.log('查詢參數:', url.searchParams); // URLSearchParams 對象
console.log('哈希:', url.hash);          // '#hash'
console.log('完整 URL:', url.href);      // 'https://www.example.com:8080/path?query=value#hash'
console.log('源:', url.origin);          // 'https://www.example.com'
console.log('用戶名:', url.username);    // ''
console.log('密碼:', url.password);      // ''// 3. 修改 URL 屬性
url.protocol = 'http:';
url.hostname = 'example.com';
url.port = '80';
url.pathname = '/new-path';
url.search = '?new=query';
url.hash = '#new-hash';
url.username = 'user';
url.password = 'pass';// 4. URL 字符串化
console.log('URL 字符串:', url.toString());
console.log('URL JSON:', url.toJSON());

2. URLSearchParams 類

const { URLSearchParams } = require('url');// 1. 創建 URLSearchParams 對象
const params = new URLSearchParams('key1=value1&key2=value2');// 2. 添加參數
params.append('key3', 'value3');
params.append('key3', 'value4'); // 可以添加同名參數// 3. 獲取參數
console.log('獲取參數:', params.get('key1'));     // 'value1'
console.log('獲取所有參數:', params.getAll('key3')); // ['value3', 'value4']// 4. 檢查參數是否存在
console.log('參數是否存在:', params.has('key1')); // true// 5. 刪除參數
params.delete('key2');// 6. 設置參數
params.set('key1', 'new-value'); // 替換已存在的參數// 7. 遍歷參數
for (const [key, value] of params) {console.log(`${key}: ${value}`);
}// 8. 轉換為字符串
console.log('參數字符串:', params.toString());// 9. 排序參數
params.sort();// 10. 清空參數
params.forEach((value, key) => {params.delete(key);
});

3. URL 解析和格式化

const { URL, URLSearchParams } = require('url');// 1. 解析 URL
function parseURL(urlString) {try {const url = new URL(urlString);return {protocol: url.protocol,hostname: url.hostname,port: url.port,pathname: url.pathname,search: url.search,hash: url.hash,username: url.username,password: url.password,origin: url.origin};} catch (error) {console.error('URL 解析錯誤:', error);return null;}
}// 2. 構建 URL
function buildURL(options) {const url = new URL('https://example.com');if (options.protocol) url.protocol = options.protocol;if (options.hostname) url.hostname = options.hostname;if (options.port) url.port = options.port;if (options.pathname) url.pathname = options.pathname;if (options.search) url.search = options.search;if (options.hash) url.hash = options.hash;if (options.username) url.username = options.username;if (options.password) url.password = options.password;return url.toString();
}// 3. 解析查詢字符串
function parseQueryString(queryString) {const params = new URLSearchParams(queryString);const result = {};for (const [key, value] of params) {result[key] = value;}return result;
}// 4. 構建查詢字符串
function buildQueryString(params) {const searchParams = new URLSearchParams();for (const [key, value] of Object.entries(params)) {searchParams.append(key, value);}return searchParams.toString();
}

4. URL 驗證和規范化

const { URL } = require('url');// 1. 驗證 URL
function isValidURL(urlString) {try {new URL(urlString);return true;} catch (error) {return false;}
}// 2. 規范化 URL
function normalizeURL(urlString) {try {const url = new URL(urlString);// 移除默認端口if (url.port === '80' && url.protocol === 'http:') {url.port = '';}if (url.port === '443' && url.protocol === 'https:') {url.port = '';}// 規范化路徑url.pathname = url.pathname.replace(/\/+/g, '/');if (url.pathname !== '/' && url.pathname.endsWith('/')) {url.pathname = url.pathname.slice(0, -1);}return url.toString();} catch (error) {return urlString;}
}// 3. 解析相對 URL
function resolveURL(base, relative) {try {return new URL(relative, base).toString();} catch (error) {return null;}
}// 4. 提取 URL 組件
function extractURLComponents(urlString) {try {const url = new URL(urlString);return {protocol: url.protocol.replace(':', ''),domain: url.hostname,port: url.port || (url.protocol === 'https:' ? '443' : '80'),path: url.pathname,query: url.search.slice(1),hash: url.hash.slice(1)};} catch (error) {return null;}
}

5. URL 編碼和解碼

const { URL, URLSearchParams } = require('url');// 1. URL 編碼
function encodeURL(urlString) {try {const url = new URL(urlString);return url.toString();} catch (error) {return encodeURI(urlString);}
}// 2. URL 解碼
function decodeURL(urlString) {try {return decodeURI(urlString);} catch (error) {return urlString;}
}// 3. 參數編碼
function encodeParams(params) {const searchParams = new URLSearchParams();for (const [key, value] of Object.entries(params)) {searchParams.append(key, value);}return searchParams.toString();
}// 4. 參數解碼
function decodeParams(queryString) {const params = new URLSearchParams(queryString);const result = {};for (const [key, value] of params) {result[key] = value;}return result;
}

6. URL 操作工具

const { URL, URLSearchParams } = require('url');// 1. URL 合并
function mergeURLs(base, relative) {try {return new URL(relative, base).toString();} catch (error) {return null;}
}// 2. URL 比較
function compareURLs(url1, url2) {try {const u1 = new URL(url1);const u2 = new URL(url2);return {sameProtocol: u1.protocol === u2.protocol,sameHost: u1.host === u2.host,samePath: u1.pathname === u2.pathname,sameQuery: u1.search === u2.search,sameHash: u1.hash === u2.hash,isEqual: u1.href === u2.href};} catch (error) {return null;}
}// 3. URL 轉換
function transformURL(urlString, options) {try {const url = new URL(urlString);if (options.protocol) url.protocol = options.protocol;if (options.hostname) url.hostname = options.hostname;if (options.port) url.port = options.port;if (options.pathname) url.pathname = options.pathname;if (options.search) url.search = options.search;if (options.hash) url.hash = options.hash;return url.toString();} catch (error) {return null;}
}// 4. URL 驗證器
class URLValidator {constructor(options = {}) {this.options = {protocols: ['http:', 'https:'],requireProtocol: true,...options};}validate(urlString) {try {const url = new URL(urlString);if (this.options.requireProtocol && !url.protocol) {return false;}if (this.options.protocols && !this.options.protocols.includes(url.protocol)) {return false;}return true;} catch (error) {return false;}}
}

7. 實際應用示例

const { URL, URLSearchParams } = require('url');// 1. URL 路由解析器
class URLRouter {constructor() {this.routes = new Map();}addRoute(pattern, handler) {this.routes.set(pattern, handler);}match(urlString) {const url = new URL(urlString);const pathname = url.pathname;for (const [pattern, handler] of this.routes) {const regex = new RegExp(pattern);if (regex.test(pathname)) {return {handler,params: this.extractParams(pattern, pathname),query: Object.fromEntries(url.searchParams)};}}return null;}extractParams(pattern, pathname) {const params = {};const patternParts = pattern.split('/');const pathParts = pathname.split('/');for (let i = 0; i < patternParts.length; i++) {if (patternParts[i].startsWith(':')) {const paramName = patternParts[i].slice(1);params[paramName] = pathParts[i];}}return params;}
}// 2. URL 參數處理器
class URLParamHandler {constructor() {this.params = new URLSearchParams();}setParams(params) {for (const [key, value] of Object.entries(params)) {this.params.set(key, value);}}getParams() {return Object.fromEntries(this.params);}removeParam(key) {this.params.delete(key);}clearParams() {this.params = new URLSearchParams();}toString() {return this.params.toString();}
}// 3. URL 重寫器
class URLRewriter {constructor(rules) {this.rules = rules;}rewrite(urlString) {const url = new URL(urlString);for (const rule of this.rules) {if (rule.pattern.test(url.pathname)) {url.pathname = url.pathname.replace(rule.pattern, rule.replacement);}}return url.toString();}
}// 4. URL 監控器
class URLMonitor {constructor() {this.history = new Map();}track(urlString) {const url = new URL(urlString);const key = url.origin + url.pathname;if (!this.history.has(key)) {this.history.set(key, {count: 0,lastAccess: null,params: new Map()});}const entry = this.history.get(key);entry.count++;entry.lastAccess = new Date();for (const [key, value] of url.searchParams) {if (!entry.params.has(key)) {entry.params.set(key, new Set());}entry.params.get(key).add(value);}}getStats() {const stats = [];for (const [url, data] of this.history) {stats.push({url,count: data.count,lastAccess: data.lastAccess,params: Object.fromEntries(Array.from(data.params.entries()).map(([key, values]) => [key,Array.from(values)]))});}return stats;}
}