小程序签名代码案例 - 微信小程序开发教程

小程序签名是保证小程序信息安全性的一种措施，以下是小程序签名的代码案例：

1. 获取小程序的access_token和ticket

const request = require('request');

// 获取access_token
function getAccessToken(appId, appSecret) {
  return new Promise((resolve, reject) => {
    const url = `https://api.weixin.qq.com/cgi-bin/token?grant_type=client_credential&appid=${appId}&secret=${appSecret}`;
    request(url, function (error, response, body) {
      if (!error && response.statusCode == 200) {
        const result = JSON.parse(body);
        resolve(result.access_token);
      } else {
        reject(error);
      }
    });
  });
}

// 获取ticket
function getTicket(accessToken) {
  return new Promise((resolve, reject) => {
    const url = `https://api.weixin.qq.com/cgi-bin/ticket/getticket?access_token=${accessToken}&type=jsapi`;
    request(url, function (error, response, body) {
      if (!error && response.statusCode == 200) {
        const result = JSON.parse(body);
        resolve(result.ticket);
      } else {
        reject(error);
      }
    });
  });
}

2. 生成noncestr和timestamp

// 生成随机字符串
function generateNonceStr(length) {
  const chars = 'ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789';
  const maxPos = chars.length;
  let nonceStr = '';
  for (let i = 0; i < length; i++) {
    nonceStr += chars.charAt(Math.floor(Math.random() * maxPos));
  }
  return nonceStr;
}

// 获取当前时间戳
function getTimestamp() {
  return parseInt(new Date().getTime() / 1000) + '';
}

3. 对签名的参数进行排序

// 对参数进行排序
function raw(args) {
  let keys = Object.keys(args);
  keys = keys.sort();
  const newArgs = {};
  keys.forEach(function (key) {
    newArgs[key.toLowerCase()] = args[key];
  });

  let str = '';
  for (let k in newArgs) {
    str += '&' + k + '=' + newArgs[k];
  }
  return str.substr(1);
}

4. 对参数进行签名

const crypto = require('crypto');

// 对参数进行签名
function sign(ticket, nonceStr, timestamp, url) {
  const params = {
    jsapi_ticket: ticket,
    nonceStr: nonceStr,
    timestamp: timestamp,
    url: url,
  };
  const string = raw(params);
  const shasum = crypto.createHash('sha1');
  shasum.update(string);
  return shasum.digest('hex');
}

5. 完整的小程序签名代码

const request = require('request');
const crypto = require('crypto');

// 获取access_token
function getAccessToken(appId, appSecret) {
  return new Promise((resolve, reject) => {
    const url = `https://api.weixin.qq.com/cgi-bin/token?grant_type=client_credential&appid=${appId}&secret=${appSecret}`;
    request(url, function (error, response, body) {
      if (!error && response.statusCode == 200) {
        const result = JSON.parse(body);
        resolve(result.access_token);
      } else {
        reject(error);
      }
    });
  });
}

// 获取ticket
function getTicket(accessToken) {
  return new Promise((resolve, reject) => {
    const url = `https://api.weixin.qq.com/cgi-bin/ticket/getticket?access_token=${accessToken}&type=jsapi`;
    request(url, function (error, response, body) {
      if (!error && response.statusCode == 200) {
        const result = JSON.parse(body);
        resolve(result.ticket);
      } else {
        reject(error);
      }
    });
  });
}

// 生成随机字符串
function generateNonceStr(length) {
  const chars = 'ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789';
  const maxPos = chars.length;
  let nonceStr = '';
  for (let i = 0; i < length; i++) {
    nonceStr += chars.charAt(Math.floor(Math.random() * maxPos));
  }
  return nonceStr;
}

// 获取当前时间戳
function getTimestamp() {
  return parseInt(new Date().getTime() / 1000) + '';
}

// 对参数进行排序
function raw(args) {
  let keys = Object.keys(args);
  keys = keys.sort();
  const newArgs = {};
  keys.forEach(function (key) {
    newArgs[key.toLowerCase()] = args[key];
  });

  let str = '';
  for (let k in newArgs) {
    str += '&' + k + '=' + newArgs[k];
  }
  return str.substr(1);
}

// 对参数进行签名
function sign(ticket, nonceStr, timestamp, url) {
  const params = {
    jsapi_ticket: ticket,
    nonceStr: nonceStr,
    timestamp: timestamp,
    url: url,
  };
  const string = raw(params);
  const shasum = crypto.createHash('sha1');
  shasum.update(string);
  return shasum.digest('hex');
}

// 获取小程序签名信息
async function getSignInfo(appId, appSecret, url) {
  const accessToken = await getAccessToken(appId, appSecret);
  const ticket = await getTicket(accessToken);
  const nonceStr = generateNonceStr(16);
  const timestamp = getTimestamp();
  const signature = sign(ticket, nonceStr, timestamp, url);

  return {
    appId: appId,
    timestamp: timestamp,
    nonceStr: nonceStr,
    signature: signature,
  };
}

module.exports = getSignInfo;

使用方法：

const getSignInfo = require('./sign');

getSignInfo(appId, appSecret, url).then((result) => {
  console.log(result);
}).catch((error) => {
  console.error(error);
});