Unknown authentication strategy "wechat"

[zhaokunyao]

http://localhost:8080/passport/login/wechat

Error: Unknown authentication strategy "wechat"
at attempt (D:\kr_project\tmp\node_modules\passport\lib\middleware\authenticate.js:193:39)
at authenticate (D:\kr_project\tmp\node_modules\passport\lib\middleware\authenticate.js:379:7)
at Layer.handle [as handle_request] (D:\kr_project\tmp\node_modules\express\lib\router\layer.js:95:5)
at next (D:\kr_project\tmp\node_modules\express\lib\router\route.js:137:13)
at Route.dispatch (D:\kr_project\tmp\node_modules\express\lib\router\route.js:112:3)
at Layer.handle [as handle_request] (D:\kr_project\tmp\node_modules\express\lib\router\layer.js:95:5)
at D:\kr_project\tmp\node_modules\express\lib\router\index.js:281:22
at Function.process_params (D:\kr_project\tmp\node_modules\express\lib\router\index.js:335:12)
at next (D:\kr_project\tmp\node_modules\express\lib\router\index.js:275:10)
at Function.handle (D:\kr_project\tmp\node_modules\express\lib\router\index.js:174:3)

=======================

`/* login using wechat account */
router.get('/login/wechat', passport.authenticate('wechat'));

/* wechat callback url */
router.get('/oauth2/redirect/wechat',
passport.authenticate('wechat', { failureRedirect: '/?error=wechat_login_failed', failureMessage: true }),
function(req, res) {
console.log('login wechat account success');
res.redirect('/employeeMode');
});

app.js

// configure wechat passport login
var WechatStrategy = require('passport-wechat');
passport.use(new WechatStrategy({
appID: process.env['WECHAT_APP_ID'],
name: 'WeChat',
appSecret: process.env['WECHAT_APP_SECRET'],
client: 'web',
callbackURL: 'http://localhost:8080/passport/oauth2/redirect/wechat',
scope: 'snsapi_base',
state: '123'
// getToken: {getToken},
// saveToken: {saveToken}
},
function(accessToken, refreshToken, profile, done) {
var provider = 'wechat';
return passportHelper.passport_call_back(provider, profile, done, db);
}
));

`