Fixed cancelToken leakage; Added AbortController support;

[DigitalBrainJS]

This PR fixes cancelToken and adds an alternative way to cancel Axios request with AbortController.

• Reworked cancelToken to fix memory leakage in case of using a persistent token for several requests. This can happen because requests cannot unsubscribe from the token after it completed since cancelToken doesn't provide any methods to do this. Possible this is a fix for CancelToken causes memory leak if re-used for multiple requests #3001 issue, but I'm not sure.
• Added AbortController support. I believe that using the existing API makes it easier to use the library.
• CancelToken and AbortController can be used simultaneously (to facilitate the transition to the new API)
• No breaking changes.

const controller = new AbortController();

axios.get('http://localhost/', {
    signal: controller.signal
}).then(
    response=> console.log('Done:', response.data), 
    err=> console.log('Failed:', err)
);

setTimeout(()=>{
    controller.abort();
}, 1000)

Recently published as axios-lab npm fork
Live demo

[Nigui]

Any updates about feature integration in master branch ? It seems to be a very useful feature for me.

[DigitalBrainJS]

Just for testing purposes, you can play around with this and some other PRs in this sandbox;

[plandem]

any blockers? It would be nice to have that support without breaking changes.

[DigitalBrainJS]

@jasonsaayman Is there any chance that this PR will be reviewed? :)

[Ruegen]

@jasonsaayman I would love to see this in too

[JamesHarrisonZa]

Im migrating our Web applications api client from fetch to axios and we have consumers passing signal so would love this to be supported.

[julesrx]

Would like to see this merged too.
I'm seeing around 40Mb more in memory heap when using a single cancel token with 5k+ requests.

[zuzusik]

Would love this one to get in!

[nickserv]

The proposal for cancelToken has been withdrawn, this should be merged to maintain cancellation support.

[DigitalBrainJS]

@jasonsaayman rebased this on 0.22.0 just in case ;)

[CodeJuggernaut]

error TS2739: Type 'AbortSignal' is missing the following properties from type 'AbortSignal': reason, throwIfAborted
error TS2322: Type 'import("/node_modules/node-abort-controller/index").AbortSignal' is not assignable to type 'AbortSignal'.

The type signatures don't match on [email protected] and [email protected], also doesn't match on [email protected]

The workaround is to cast it as any which is not good, but works until a better solution is found.

          {
            signal: options.signal as any
          }

[Hitotsubashi]

Since you had removed code "config.cancelToken.promise.then(function onCanceled(cancel) " from the file named "adapter/xhr.js" in this commit, I think lines 38~52 are no longer needed.

I try to remove lines 38~52 here and then run the script "npm run test", finally find out that all tests are passed.

[DigitalBrainJS]

Yes, but CancelToken is a public interface, so we can't be sure that user code is somehow not relying on its thenable/promise interface. IMHO, this should be kept as long as the CancelToken exists in the codebase.