Question

我们有route＆amp;这样middleware：

当我们这样做时：

//middleware
router.use((req, res, next) => {

    // check header or url parameters or post parameters for token
    let token = req.body.token || req.query.token || req.headers['x-access-token'],


        // verifies secret and checks exp
        jwt.verify(token, config.secret, (err, decoded) => {
            if (err) {
                return res.json({
                    success: false,
                    message: 'Failed to authenticate token.'
                });
            } else {
                // if everything is good, save to request for use in other routes
                res.locals.test = "test";
                req.somevariable = "variable1";

                console.log("res.locals.test inside middleware ", JSON.stringify(res.locals.test));
                console.log("req.somevariable inside middleware ", JSON.stringify(req.somevariable));

                next();

            }
        });

    next();
});

//TestRoute
router.get('/TestRoute', (req, res) => {

    console.log("res.locals.test outside middleware ", JSON.stringify(res.locals.test));
    console.log("req.somevariable outside middleware ", JSON.stringify(req.somevariable));

});

req.somevariable和res.locals.test的值undefined以外middleware

当我们这样做时：

//middleware
router.use((req, res, next) => {

    res.locals.test = "test";
    req.somevariable = "variable1";

    console.log("res.locals.test inside middleware ", JSON.stringify(res.locals.test));
    console.log("req.somevariable inside middleware ", JSON.stringify(req.somevariable));

    next();

});

//TestRoute
router.get('/TestRoute', (req, res) => {

    console.log("res.locals.test outside middleware ", JSON.stringify(res.locals.test));
    console.log("req.somevariable outside middleware ", JSON.stringify(req.somevariable));


});

在req.somevariable之外可以使用res.locals.test和middleware的值。

这里有什么问题？

Answer 1

res.locals.VARIABLENAME = req.user

VARIABLENAME（无论您将其设置为什么变量）在使用.ejs或使用该变量进行动态渲染时都可能显示为未定义。您可能会得到错误，例如变量名未定义。

这是res.locals的一个奇特之处：当您想在渲染时使用设置为res.locals的变量名时，必须在函数RENDERS the File中定义req.user！

后端：res.locals.currentUser = req.user

//THIS FUNCTION WILL RENDER PERFECTLY LETTING ME USE currentUser in my .ejs file
 upgradeForm(req, res, next) {
    let saved = req.user;
    if(req.user){
      res.render("users/upgrade");
    } else{
      req.flash("notice", "You've successfully signed in!");
      res.redirect("/");
    }
  }

但是

//THIS FUNCTION WILL SAY currentUser is UNDEFINED IN MY .ejs file
 upgradeForm(req, res, next) {
    if(req.user){
      res.render("users/upgrade");
    } else{
      req.flash("notice", "You've successfully signed in!");
      res.redirect("/");
    }
  }

除了工作功能渲染已将req.user设置为变量之外，没有代码差异（您甚至不必使用该变量）。花了我9个小时来解决这个问题，但现在您知道了！

为什么req.somevariable和res.locals不能使用jwt回调？

1 个答案: