breadcrumbCallback - allow to capture request headers/payload/etc

[snebjorn]

This have been requested before in #1490.
Quote

All XHR data (such as request body and headers)

But the proposed solution API doesn't work.

Proposed solution

init({
  dsn: 'https://some.dsn/123',
  beforeBreadcrumb (breadcrumb, hint) {
    if (breadcrumb.category === 'xhr') {
      // hint.xhr is a whole XHR object that you can use to modify breadcrumb
    }
    return breadcrumb;
  }
})

The hint.xhr is a XMLHttpRequest which to my knowledge doesn't have access to the request data. Only the response data.

I understand this isn't included by default due to the 200kb (as of writing) size limit. However the request data is hugely beneficial when debugging an issue.

Please allow us to also capture the request data in the beforeBreadcrumb hook. And perhaps add a function that can check if the breadcrumb have exceeded the size limit so we can strip less relevant data from the breadcrumb.

Also asked here
Sentry Forum
StackOverflow

[kamilogorek]

XMLHttpRequest is the only construct available during its lifetime. It acts as both, request and response. There's nothing more we can provide.

hint.xhr = request
hint.xhr.reponse = response

[snebjorn]

I had a quick look at the source. I'm not sure this is the correct place. But it seems like you're adding extra stuff that is not available in the XMLHttpRequest, like the request URL and method. Should be possible somehow to also add the request body as well.

sentry-javascript/packages/browser/src/integrations/breadcrumbs.ts

Line 397 in df0576f

function(this: SentryWrappedXMLHttpRequest, ...args: any[]): void {

[kamilogorek]

Currect, but only because of this reason:

 // touching statusCode in some platforms throws
// an exception
if (xhr.__sentry_xhr__) {
  xhr.__sentry_xhr__.status_code = xhr.status;
}

Because it's always the same XHR object that was used to send a request, you can do xhr.whatever = 123 for your own requests and it'll be available inside the hint as well :)

[victor95pc]

@kamilogorek @snebjorn, any news? It would be awesome to have access to the request body, it would generate really helpful breadcrumbs for requests, my quick hack is to send the params of the last request

Example only using response