An instance doesn't seem to have CancelToken property

An instance doesn’t seem to have CancelToken property

Lately I needed to time some of the requests made by axios, so following the documentation I created and interceptor for an instance of axios (since I do not want to affect all axios requests, only specific ones):

var axios = require('axios').create(); // Create new instance of axios, to use interceptors safely

function setAxiosMeta(config, meta) {
    config.meta = config.meta || {};

    config.meta = Object.assign(config.meta, meta);
}

function getAxiosMeta(config) {
    config.meta = config.meta || {};

    return config.meta;
}

axios.interceptors.request.use(function (config) {
    setAxiosMeta(config, {
        requestStartTime: Date.now()
    });

    return config;
}, function (error) {
    return Promise.reject(error);
});

axios.interceptors.response.use(function (response) {
    var meta = getAxiosMeta(response.config);

    setAxiosMeta(response.config, {
        requestTime: Date.now() - meta.requestStartTime,
        requestId: response.headers['x-yt-request-id'],
        proxy: response.headers['x-yt-proxy']
    });

    return response;
}, function (error) {
    return Promise.reject(error);
});

We also use request cancellation:

var cancellation = axios.CancelToken.source();

And this line now throws and error:

Uncaught TypeError: Cannot read property 'source' of undefined
    at Object.core._createRequestWithCancellation (yt.js:826)
    ....

Is there a known workaround for creating Cancellation when working with and instance of axios? It isn’t very clear what an instance is, at least after I encountered this behaviour. At first I thought that instance is the same as axios itself, but can be additionally configured.

Context

• axios version: e.g.: v0.17.1
• Environment: e.g.: node v8.9.4, chrome 62, ubuntu Xenial

[dingziqi]

@dlahuta you did not return config in your request interceptors, this is the reason of Cannot read property 'cancelToken' of undefined

[adrianbienias]

If you need to have cancelToken in instance (and probably also isCancel) just add them:

const instance = axios.create();
instance.CancelToken = axios.CancelToken;
instance.isCancel = axios.isCancel;