Can I throw error in axios post based on response status

Question

Is it possible to throw an error on purpose inside the .then() block in axios? For instance, if the api responds with 204 status code, could I throw an error and run the catch block?

For example:

axios.post('link-to-my-post-service', {
        json-input
    }).then(response => {
        if (response.status === 200) {
            //proceed...
        }
        else {
            // throw error and go to catch block
        }
    }).catch(error => {
        //run this code always when status!==200
    });

EDIT

I tried this, but it didn't work:

var instance = axios.create({
            validateStatus: function (status)
            {
                return status == 200;
            }
        });
axios.post('link-to-my-post-service', {input: myInput}, instance)
    .then(response => {
            dispatch({
                    type: "FETCH_SUCCESS",
                    payload: response.data
                });
        }).catch(error => {
            dispatch({
                type: "FETCH_FAILED",
                payload: error
            });
        });

When I get a status code 204, still the executed block is then() block instead of the catch block.

EDIT 2

The correct answer using Ilario's suggestion is this:

var instance = axios.create({
            validateStatus: function (status)
            {
                return status == 200;
            }
        });
instance.post('link-to-my-post-service', {input: myInput})
    .then(response => {
            dispatch({
                    type: "FETCH_SUCCESS",
                    payload: response.data
                });
        }).catch(error => {
            dispatch({
                type: "FETCH_FAILED",
                payload: error
            });
        });

Now when the status code is not equal to 200 the catch block code is executed.

Ilario Engler · Accepted Answer · 2017-05-08T11:23:18.010

If you give a look at the GitHub Project Page you will notice following option description.

/* `validateStatus` defines whether to resolve or reject the promise for a given
 * HTTP response status code. If `validateStatus` returns `true` (or is set to `null`
 * or `undefined`), the promise will be resolved; otherwise, the promise will be
 */ rejected.
validateStatus: function (status) {

    return status >= 200 && status < 300; // default
},

So you could create an Instance with your own configuration.

var instance = axios.create({

   validateStatus: function (status) {

        return status == 200;
    },
});

You could also set defaults. These will be applied to every request.

axios.defaults.validateStatus = () => {

    return status == 200;
};

UPDATE 1

To set the config only on a specific operation you could replace "config" with your desired values or methods.

axios.post(url[, data[, config]])

UPDATE 2

I tried this, but it didn't work.

You cannot pass the instance to axios.post(). You must call post on the new instance.

var instance = axios.create({

    validateStatus: function (status) {
        return status == 200;
    }
});

instance.post('url', data, config);

jenny · Answer 2 · 2017-05-08T11:42:53.583

14

Thank you very much for your suggestions. The answer was simpler than I expected.

I didn't want to set any default options to change the behavior of axios, so I just tried something like the code below, and it worked. Every time the code throw new Error("Error"); is executed, the catch block code is executed after that.

axios.post('link-to-my-post-service', {
        json-input
    }).then(response => {
        if (response.status === 200) {
            //proceed...
        }
        else {
            // throw error and go to catch block
            throw new Error("Error");
        }
    }).catch(error => {
        //when throw "Error" is executed it runs the catch block code
        console.log(error)
    });

edited May 08 '17 at 11:42

answered May 08 '17 at 10:41

jenny

933
2
11
26

You're welcome :) Why you do not wanna set default options? Or create an instance with these options set? Do you need it only with a specific request? Updated my answer. – Ilario Engler May 08 '17 at 10:52
1

Thanks again for the feedback! I need it only for a specific request – jenny May 08 '17 at 11:15
Okaay. So if you need it only for a specific request, you can do it as you've proposed or take a look at "Update 1" in my answer. – Ilario Engler May 08 '17 at 11:17
3

`if (response.status >= 200 && response.status < 300) {` is safer – Martin Malinda May 16 '20 at 11:17

Can I throw error in axios post based on response status

2 Answers2