I am having difficulty doing what should be a simple POST of some test results to appveyor. The build happens on appveyor, and the tests run on a special set of hardware outside of Appveyor. I want to POST the results back to appveyor.

I am following the instructions here:
https://www.appveyor.com/docs/running-tests/#pushing-real-time-test-results-to-build-console

I have tried 3 approaches:
1) curl
2) POST with node's deprecreated `request` module
3) POST with node-fetch (which is a whatwg-fetch implementation)

In each case I am unable to see the test results in appveyor. And the second two cases yield different status codes for their responses. (404 and 415 respectively).

I am using "Content-Type: multipart/form-data" and wondering if the appveyor server that handles the form-data correctly?

Also note that for the 3rd approach (node-fetch), I have tried 3 implementations for nodejs and get the same results (form-data, formdata-polyfill and formdata-node). I tried a few implementations because I have read some server/clients have differences on how they interpret/implement the form-data spec.

Are there known issues POSTing from different clients?

Below are some simplified examples of the code I have tried that fails.

```bash
$ curl --verbose -F 'file={FILEPATH}' -H "Authorization: Bearer {TOKEN}" "https://ci.appveyor.com/api/testresults/junit/{JOBID}"
#No errors with curl... but if I look in appveyor, I see "The build job has not produced any test results."
```

```typescript
import request from 'request';
import { createReadStream } from 'graceful-fs';
import fetch from 'node-fetch'; //Using version 2.6.2 because it is CommonJS, whereas 3.x is ES module
import FormData from 'form-data';
import * as path from 'path';

//Example with `request` module (which is deprecated)
const appveyorUploadWithRequest = async (filePath: string, jobId: string, token: string) => {
  const url = `https://ci.appveyor.com/api/testresults/junit/${jobId}`;
  const headers = {
    Authorization: `Bearer ${token}`,
    'Content-Type': 'multipart/form-data'
  };
  await new Promise((resolve, reject) => {
    request.post(
      {
        url,
        headers,
        formData: {
          file: createReadStream(filePath)
        }
      },
      (error, response, body) => {
        if (error != null) {
          reject(error);
          return;
        }
        const bodyAsString = body.toString();
        if (response.statusCode >= 200 && response.statusCode < 300) {
          resolve(bodyAsString);
        } else {
          debugger;
          reject(new Error(`POST ${url}, file: ${filePath}, failed: status ${response.statusCode}: ${bodyAsString}`));
        }
      }
    );
  });
};

//Example with node-fetch
const appveyorUploadWithFetch = async (filePath: string, jobId: string, token: string) => {
  const url = `https://ci.appveyor.com/api/testresults/junit/${jobId}`;
  const formdata = new FormData();
  formdata.append('file', createReadStream(filePath), path.basename(filePath));
  const headers: HeadersInit = {
    Authorization: `Bearer ${token}`,
    'Content-Type': 'multipart/form-data'
   //Also tried adding `...formdata.getHeaders()` which includes boundary
  };
  const response = await fetch(url, {
    method: 'POST',
    body: formdata as any,
    headers: headers
  });
  if (response.ok) {
    return response.json();
  } else {
    debugger;
    throw new Error(`POST ${url}, file: ${filePath}, failed: status ${response.status}: ${response.statusText}`);
  }
};

(async () => {
  await appveyorUploadWithRequest('/tmp/result.xml', 'JOBID', 'TOKEN');
  //Throws 404: Job not found or access denied
})();

(async () => {
  await appveyorUploadWithFetch('/tmp/result.xml', 'JOBID', 'TOKEN');
  //Throws status 415.
})();