Binance API Document Watch Dog

readme.md

mkdir binance-changelog-watcher && cd $_
npm init -y
npm i cheerio dotenv
node watcher.js

binance-api-change-log-watch.ts

// watcher.js
// 每秒抓取 https://developers.binance.com/docs/derivatives/change-log
// 发现正文变化则把“新增/变更的行”发到 Telegram

import fs from 'fs';
import path from 'path';
import process from 'process';
import dotenv from 'dotenv';
import cheerio from 'cheerio';

dotenv.config();

const URL = 'https://developers.binance.com/docs/derivatives/change-log';
const BOT_TOKEN = process.env.TELEGRAM_BOT_TOKEN;   // 必填
const CHAT_ID   = process.env.TELEGRAM_CHAT_ID;     // 必填

if (!BOT_TOKEN || !CHAT_ID) {
  console.error('请设置 TELEGRAM_BOT_TOKEN 和 TELEGRAM_CHAT_ID');
  process.exit(1);
}

// Node 18+ 自带 fetch
const SNAPSHOT_FILE = path.join(process.cwd(), 'last_snapshot.txt');

// 读取上次快照（逐行集合）
function loadPrevLines() {
  try {
    const txt = fs.readFileSync(SNAPSHOT_FILE, 'utf8');
    return new Set(txt.split('\n'));
  } catch {
    return new Set();
  }
}

// 保存本次快照
function saveLines(linesArr) {
  fs.writeFileSync(SNAPSHOT_FILE, linesArr.join('\n'), 'utf8');
}

// 提取目标 div 的“可读文本”并做基础规范化（去多空格、trim）
function extractNormalizedLines(html) {
  const $ = cheerio.load(html);
  const $div = $('div.theme-doc-markdown.markdown').first();
  if ($div.length === 0) return [];

  // 把标题与列表/段落拆成行，尽量保留语义
  const lines = [];
  $div.find('h1, h2, h3, p, li, code, pre, ul, ol, hr').each((_, el) => {
    const tag = el.tagName?.toLowerCase() || '';
    if (tag === 'hr') {
      lines.push('---');
      return;
    }
    // 代码块/行内代码尽量直接取文本
    const text = $(el).text().replace(/\s+/g, ' ').trim();
    if (text) {
      // 给标题行加点前缀，有助于 diff 时定位
      if (tag === 'h1' || tag === 'h2' || tag === 'h3') {
        lines.push(`# ${text}`);
      } else if (tag === 'li') {
        lines.push(`- ${text}`);
      } else {
        lines.push(text);
      }
    }
  });

  return lines;
}

// 计算“新增/变更行”
// 简单策略：把本次所有行与上次集合比对，不在上次集合内的就是新增（或改动后的新行）
function diffNewLines(prevSet, currLines) {
  const out = [];
  for (const line of currLines) {
    if (!prevSet.has(line)) out.push(line);
  }
  return out;
}

async function sendToTelegram(text) {
  // Telegram 单条消息长度有限，做分段
  const MAX = 3500; // 留些余量
  const chunks = [];
  let buf = '';
  for (const line of text.split('\n')) {
    if ((buf + line + '\n').length > MAX) {
      chunks.push(buf);
      buf = '';
    }
    buf += line + '\n';
  }
  if (buf) chunks.push(buf);

  for (const chunk of chunks) {
    const url = `https://api.telegram.org/bot${BOT_TOKEN}/sendMessage` +
      `?chat_id=${encodeURIComponent(CHAT_ID)}` +
      `&text=${encodeURIComponent(chunk)}`;
    const resp = await fetch(url);
    if (!resp.ok) {
      const errTxt = await resp.text().catch(() => '');
      console.error('Telegram 发送失败', resp.status, errTxt);
    }
    // 避免消息过快触发限频
    await new Promise(r => setTimeout(r, 300));
  }
}

let prevSet = loadPrevLines();
let isFetching = false;

async function tick() {
  if (isFetching) return; // 防止重入
  isFetching = true;
  try {
    const res = await fetch(URL, {
      headers: {
        'User-Agent': 'Mozilla/5.0 (ChangeLogWatcher/1.0)',
        'Cache-Control': 'no-cache',
        'Pragma': 'no-cache',
      },
    });
    if (!res.ok) {
      console.error('抓取失败：', res.status, await res.text().catch(() => ''));
      return;
    }
    const html = await res.text();
    const currLines = extractNormalizedLines(html);

    if (currLines.length === 0) {
      console.warn('未提取到正文，可能页面结构变化');
      return;
    }

    const delta = diffNewLines(prevSet, currLines);

    if (delta.length > 0) {
      // 组装消息：把新增内容发到 Telegram
      const header = `Binance Derivatives Change Log 发现更新：\n${URL}\n\n`;
      const body = delta.join('\n');
      await sendToTelegram(header + body);

      // 刷新快照
      saveLines(currLines);
      prevSet = new Set(currLines);
      console.log(new Date().toISOString(), `发现 ${delta.length} 行变更，已推送`);
    } else {
      // 无更新
      // console.log(new Date().toISOString(), '无变化');
    }
  } catch (e) {
    console.error('tick 异常：', e);
  } finally {
    isFetching = false;
  }
}

// 每秒轮询（注意：1s 很激进，若被限频可改为 5s/10s）
tick();
setInterval(tick, 1000);

env

TELEGRAM_BOT_TOKEN=123456:ABCDEF...
TELEGRAM_CHAT_ID=-1001234567890