Filesystem.downloadFile fails for unknown reason

[bengrah-miller]

Bug Report

Plugin(s)

"@capacitor/filesystem": "^6.0.1",

Capacitor Version

npx cap doctor
   Capacitor Doctor   

Latest Dependencies:       

  @capacitor/cli: 6.1.2    
  @capacitor/core: 6.1.2   
  @capacitor/android: 6.1.2
  @capacitor/ios: 6.1.2    

Installed Dependencies:    

  @capacitor/ios: not installed
  @capacitor/cli: 6.0.0        
  @capacitor/android: 6.0.0    
  @capacitor/core: 6.0.0       

[success] Android looking great! 👌

Platform(s)

Android

Current Behavior

I've got the following code in place to download a file:

    Filesystem.downloadFile({
      method: 'POST',
      data: payload,
      url: this.dataService.downloadFileAttachment(),
      headers: headers,
      directory: Directory.Documents,
      path: "test.bin",
      progress: true
    })
      .then((result) => {
        console.info("result:", result)
      })
      .catch((e) => {
        console.error("error:", e)
      })

The code runs, doesn't appear to download anything and fails pretty much instantly, I get the following error on the console:

VM3:339 result Filesystem.downloadFile (#70225240)
8054.da0d23dc07e24a1c.js:1  error: ke: Error downloading file: http://endpoint.com/download
    at returnResult (<anonymous>:943:32)
    at win.androidBridge.onmessage (<anonymous>:918:21)

Expected Behavior

File should be downloaded

Code Reproduction

See above

Other Technical Details

Additional Context

[me-cedric]

I'm encountering a similar issue and I believe that the data is not sent as a post payload.
I have to use the patched window.fetch method to perform the post, convert the result to base64 and save manually since I'm using CapacitorHttp.
But the resulting pdf file is just blank pages.

[bengrah-miller]

@me-cedric Just a quick one, not sure if this applies to you or not - our endpoint is meant to send back a binary (octet-stream), but we ended up switching to CapacitorHttp.post() - when we did this, the response is coming back in base64 encoding - using atob() turns it back into the binary that we can see in Postman