How to read file input's file content from POST request via WebRequest API?

[BenjaminH]

Hi,

we are trying to block and read the content of (a) file(s) that are
uploaded via form with file input using the WebRequest API and
onBeforeRequest. We cannot get the file content, but only its file
name using requestBody.formData. In our tests we always get formData
which seems not to include file content readable to us. raw that would
include file content as shown in the documentation is undefined. Is
there a way to access the file content?

Object {frameId: 0, method: "POST", parentFrameId: -1, requestBody:
Object, requestId: "12802"…}
frameId: 0
method: "POST"
parentFrameId: -1
requestBody: Object
> formData: Object
>>files2[]: Array[1]
>>files[]: Array[1]
>>> 0: "myphoto.jpg"
>>> length: 1
>>> __proto__: Array[0]
>>sel: Array[1]
>>tex: Array[1]
>requestId: "12802"
>tabId: 196
>timeStamp: 1368715914204.736
>type: "main_frame"
>url: "http://removed-for-privacy-reasons.com/mytest.php"