What should I do if "Error: Invalid token" occurs when using vue-resource in a Vue application?

What should I do if "Error: Invalid token" occurs when using vue-resource in a Vue application?

Vue.js is a very popular front-end framework. Its core is lightweight data binding and component system. It is widely used in the development and building of web applications. vue-resource is a plug-in provided by the Vue.js framework for processing http requests and responses. Vue-resource can help us complete http requests and responses from the front end to the back end, thereby realizing a development model where the front and back ends are separated. But in the process of using vue-resource, we may encounter some errors. One of the common errors is "Error: Invalid token". This article will detail the causes and solutions to this error.

1. Cause of the error

If you get an error message of "Error: Invalid token" when using vue-resource, then this is most likely due to incorrect content in the request header. caused by legal characters. The HTTP protocol stipulates that the request header cannot contain some special characters, such as tab key, carriage return, line feed, space, etc. If the request header contains these illegal characters, it will cause an "Error: Invalid token" error.

2. Solution

We can solve the "Error: Invalid token" problem in the following ways.

Method 1: Use the encodeURIComponent() function

When the request header contains illegal characters, we can use the encodeURIComponent() function to encode the request header parameters. For example:

var headers = {
    'Content-Type': 'application/x-www-form-urlencoded;charset=UTF-8'
};

var data = {
    'username': 'admin',
    'password': '123456'
};

this.$http.post('/login', data, {headers: headers}).then(function(response){
    console.log(response.body);
}, function(response){
    console.log(response);
});

In the above code, we set "Content-Type: application/x-www-form-urlencoded;charset=UTF-8" in the request header, and use encodeURIComponent( for the request parameters ) function is encoded to ensure that the request header does not contain any illegal characters.

Method 2: Use $http.interceptors interceptor

$http.interceptors interceptor can intervene between the request and the response, and can be used to dynamically add, remove, and modify requests. head. When using the $http.interceptors interceptor, we need to add the following code in Vue:

Vue.http.interceptors.push(function(request, next){
    request.headers.set('Authorization', 'Bearer ' + localStorage.getItem('token'));
    next(function (response) {
        if(response.status === 401){
            localStorage.removeItem('token');
            this.$router.push('/login');
        }
    });
});

In the above code, we will carry an Authorization field in the request header in each request, whose value is our The token value used in the project. If the response status returned from the server is 401, indicating unauthorized, we will delete the locally saved token value and redirect to the login page.

Method 3: Pay attention to the format of the request header

The format of the request header is very important. Normally, we should try not to contain illegal characters in request header parameters. You can use double quotes to wrap the parameter content in the parameter part of the request header to ensure that the format of the request header is correct.

var headers = {
    "Content-Type": 'application/json;charset=UTF-8',
    "Authorization": 'Bearer ' + localStorage.getItem('token')
};

Note: If an "Error: Invalid token" error occurs when using Vue-resource in a Vue project, you can give priority to solving the above three methods. If none of the above methods solve the problem, you may need to dig deeper to analyze the specific cause of the error.

Conclusion

When using Vue-resource in a Vue project, it is very common to encounter the error "Error: Invalid token". We can solve this problem by using the encodeURIComponent() function, the $http.interceptors interceptor and paying attention to the format of the request header. Avoiding the use of illegal characters and ensuring that the format of the request header is correct is the key to avoiding such problems. In actual project development, we need to learn meticulous debugging methods, solve various problems, and improve our development skills.

The above is the detailed content of What should I do if "Error: Invalid token" occurs when using vue-resource in a Vue application?. For more information, please follow other related articles on the PHP Chinese website!