1、先登录微信公众平台，进入“公众号设置”的“功能设置”里填写“JS接口安全域名”，进入“基础配置”，将服务端部署ip配置到IP白名单中。
2、引入JS文件 在需要调用JS接口的页面引入如下JS文件，（支持 https）：http://res.wx.qq.com/open/js/jweixin-1.6.0.js
3、通过config接口注入权限验证配置，所需参数从服务端接口获取；
服务端生成签名时需要配置当前网页的URL（不包含#及其后面部分，需域名，本地ip试了不行），可由前端将调用扫一扫的页面url传给服务端生成签名的接口；
前端代码
let signData = await request('api/demo/auth/sign', { method: 'POST', body: {
"url": window.location.origin + window.location.pathname, //当前网页的URL传给后端
} })
console.log('signData',signData);
wx.config({
debug: true, // 开启调试模式,调用的所有api的返回值会在客户端alert出来，若要查看传入的参数，可以在pc端打开，参数信息会通过log打出，仅在pc端时才会打印。
appId: 'wx7048dabe52cXXXXX', // 必填，公众号的唯一标识
timestamp: signData.timestamp, // 必填，生成签名的时间戳
nonceStr: signData.nonceStr, // 必填，生成签名的随机串
signature: signData.signature,// 必填，签名
jsApiList: ['scanQRCode'] // 必填，需要使用的JS接口列表
});
后端代码
@PostMapping("/sign")
public SignResp sign(@RequestBody @Valid SignReq req) {
try {
String fkToken = redisTemplate.opsForValue().get(FK_TOKEN_KEY_PREFIX + APP_ID);
if (fkToken == null) {
synchronized (FK_TOKEN_KEY_PREFIX) {
fkToken = redisTemplate.opsForValue().get(FK_TOKEN_KEY_PREFIX + APP_ID);
if (fkToken == null) {
Request request = new Request.Builder()
.url(genUri("fkAccessToken"))
.get()
.build();
OkHttpClient okHttpClient = new OkHttpClient();
Response response = okHttpClient.newCall(request).execute();
String result = response.body().string();
log.info("fkAccessToken result: {}", result);
JSONObject jsonObject = JSONUtil.parseObj(result);
fkToken = jsonObject.getStr("access_token");
redisTemplate.opsForValue().set(FK_TOKEN_KEY_PREFIX + APP_ID, fkToken);
redisTemplate.expire(FK_TOKEN_KEY_PREFIX + APP_ID, 7000, TimeUnit.SECONDS);
}
}
}
String ticket = redisTemplate.opsForValue().get(TICKET_KEY_PREFIX + APP_ID);
if (ticket == null) {
Request request = new Request.Builder()
.url(genUri("ticket", fkToken))
.get()
.build();
OkHttpClient okHttpClient = new OkHttpClient();
Response response = okHttpClient.newCall(request).execute();
String result = response.body().string();
log.info("sign result: {}", result);
JSONObject jsonObject = JSONUtil.parseObj(result);
ticket = jsonObject.getStr("ticket");
redisTemplate.opsForValue().set(TICKET_KEY_PREFIX + APP_ID, ticket);
redisTemplate.expire(TICKET_KEY_PREFIX + APP_ID, 7000, TimeUnit.SECONDS);
}
// 签名
String noncestr = IdUtil.simpleUUID();
String timestamp = String.valueOf(LocalDateTime.now().toInstant(ZoneOffset.of("+8")).toEpochMilli());
// String url = SIGN_PAGE_URI;
String content = "jsapi_ticket=" + ticket
+ "&noncestr=" + noncestr
+ "×tamp=" + timestamp
+ "&url=" + req.url;
SignResp signResp = new SignResp();
signResp.setNonceStr(noncestr);
signResp.setTimestamp(timestamp);
signResp.setSignature(SecureUtil.sha1(content));
log.info("signResp: {}", signResp);
return signResp;
} catch (Exception e) {
throw new RuntimeException(e);
}
}
private String genUri(String type, String... args) {
switch (type) {
case "grant": // 获取授权码
return "https://open.weixin.qq.com/connect/oauth2/authorize?"
+ "appid=" + APP_ID
+ "&redirect_uri=" + URLUtil.encode(REDIRECT_URI, StandardCharsets.UTF_8)
+ "&response_type=code"
+ "&scope=snsapi_base"
+ "&state=STATE"
+ "#wechat_redirect";
case "accessToken": // 获取微信用户accessToken
return "https://api.weixin.qq.com/sns/oauth2/access_token?"
+ "appid=" + APP_ID
+ "&secret=" + APP_SECRET
+ "&code=" + args[0]
+ "&grant_type=authorization_code";
case "refreshAccessToken": // 刷新微信用户accessToken
return "https://api.weixin.qq.com/sns/oauth2/refresh_token?"
+ "appid=" + APP_ID
+ "&grant_type=refresh_token"
+ "&refresh_token=" + args[0];
case "ticket": // 获取jsapi_ticket
return "https://api.weixin.qq.com/cgi-bin/ticket/getticket?"
+ "access_token=" + args[0]
+ "&type=jsapi";
case "fkAccessToken": // 获取公众号accessToken
return "https://api.weixin.qq.com/cgi-bin/token?"
+ "grant_type=client_credential"
+ "&appid=" + APP_ID
+ "&secret=" + APP_SECRET;
}
throw new RuntimeException();
}
4、调用微信扫一扫；
wx.scanQRCode({
needResult: 1, // 默认为0，扫描结果由微信处理，1则直接返回扫描结果，
scanType: ["qrCode","barCode"], // 可以指定扫二维码还是一维码，默认二者都有
success: function (res) {
var result = res.resultStr; // 当needResult 为 1 时，扫码返回的结果
console.log(result);
request('api/demo/user/query', {
method: 'POST', body: {
"number": result
}
}).then(res => {
console.log(res);
jumpPage('/search/result', JSON.parse(res.data))
})
}
})
5、如果要获取微信用户信息，需网页鉴权-Oauth2，只有通过微信认证的服务号有权限，订阅号不行，进入“公众号设置”的“功能设置”里进行网页授权域名填写；参考链接
6、成功demo（前端获取到code后传给服务端接口，接口返回openId，或者用户信息）
前端代码 （拿到授权码后请求后端获取AccessToken）
let openId = ''
let code = this.getUrlParam('code','?' + window.location.href.split('?')[1])
const url = `https://open.weixin.qq.com/connect/oauth2/authorize?appid=xxx&redirect_uri=https://xxx.com/deme/&response_type=code&scope=snsapi_base&state=STATE`
if(!sessionStorage.getItem('openId')){
if(code){
request('api/demo/auth/receive', { method: 'POST', body: {
code: code,
} }).then(res=>{
openId = res.openId
sessionStorage.setItem('openId',openId)
this.getUserInfo() //通过openId获取用户信息
history.pushState('', '', 'https://xxx.com/deme/')
})
}else{
window.location.href = url
}
}else{
this.getUserInfo() //通过openId获取用户信息
}
// 回调回来的地址是：https://xxx.com/deme/?code=xxxxxx&state=xxx
// 如果你是使用hash路由的，一般的取url参数的方法会有点小问题，需要手动调整下
getUrlParam = (name, location) => {
const reg = new RegExp('(^|&)' + name + '=([^&]*)(&|$)');
const { hash, search } = window.location;
const result = ((location||(hash || search)).split('?')[1] || '').match(reg);
return result ? decodeURIComponent(result[2]) : null;
}
后端代码 （获取AccessToken）
@PostMapping("/receive")
public ReceiveResp receive(@RequestBody @Valid ReceiveReq req) {
log.info("receiveReq: {}", req);
Request request = new Request.Builder()
.url(genUri("accessToken", req.code))
.get()
.build();
try {
OkHttpClient okHttpClient = new OkHttpClient();
Response response = okHttpClient.newCall(request).execute();
String result = response.body().string();
log.info("receive result: {}", result);
JSONObject jsonObject = JSONUtil.parseObj(result);
String openId = jsonObject.getStr("openid");
if (StringUtils.isBlank(openId)) {
throw new RuntimeException("error");
}
redisTemplate.opsForValue().set(TOKEN_KEY_PREFIX + openId, jsonObject.getStr("access_token"));
redisTemplate.expire(TOKEN_KEY_PREFIX + openId, 7000, TimeUnit.SECONDS);
redisTemplate.opsForValue().set(REFRESH_TOKEN_KEY_PREFIX + openId, jsonObject.getStr("access_token"));
redisTemplate.expire(REFRESH_TOKEN_KEY_PREFIX + openId, 29, TimeUnit.DAYS);
ReceiveResp resp = new ReceiveResp();
resp.setOpenId(openId);
return resp;
} catch (Exception e) {
throw new RuntimeException("error", e);
}
}
后端代码 （获取缓存的AccessToken，如已过期则刷新AccessToken）
private String getAccessToken(String openId) throws IOException {
String accessToken = redisTemplate.opsForValue().get(TOKEN_KEY_PREFIX + openId);
if (accessToken == null) {
String refreshAccessToken = redisTemplate.opsForValue().get(REFRESH_TOKEN_KEY_PREFIX + openId);
if (refreshAccessToken == null) {
throw new RuntimeException("会话已过期，请重新登录");
}
Request request = new Request.Builder()
.url(genUri("refreshAccessToken", refreshAccessToken))
.get()
.build();
OkHttpClient okHttpClient = new OkHttpClient();
Response response = okHttpClient.newCall(request).execute();
String result = response.body().string();
JSONObject jsonObject = JSONUtil.parseObj(result);
redisTemplate.opsForValue().set(TOKEN_KEY_PREFIX + openId, jsonObject.getStr("access_token"));
redisTemplate.expire(TOKEN_KEY_PREFIX + openId, 7000, TimeUnit.SECONDS);
return jsonObject.getStr("access_token");
}
return accessToken;
}
7、官方链接： JSSDK使用步骤 JS-SDK使用权限签名算法
8、踩坑小记
在微信扫一扫和Oauth2认证的官方文档里，都有提到accessToken，但两者并不是一个东西，获取它们的接口也不相同。扫一扫里的accessToken属于公众号，而Oauth2里的accessToken属于微信用户。扫一扫的签名接口的入参accessToken指的是公众号的accessToken。