PUT and DELETE Request with Content Type "multipart/form-data" in cypress

Question

I'm a test-developer working on cypress API testing for the first time. I was asked to test 3 APIs with content type "multipart/form-data". The first one I needed to test it as a POST, but instead the second and the third ones respectively as a PUT and a DELETE.

The POST request is about uploading three files and worked perfectly with the following code:

//variable name
    const param = 'parameters_file.xml';
    const data = 'data_file.pdf';
    const index = 'index_file.xml';

    //Datas of the request
    const method = 'POST'
    const url = 'https://myapi/myapi'

    //fileType
    const fileTypeXML = 'application/xml';
    const fileTypePDF = 'application/pdf';

    //formData
    const formData = new FormData();


    //Conversion parameters file -> need to be stated as a function in the future
    cy.fixture(param, 'binary')
        .then((resParam) => Cypress.Blob.binaryStringToBlob(resParam, fileTypeXML))
        .then((blobParam) => {
            formData.set('PARAMFILE', blobParam, param); //adding file to formdata
        })
        
    //Conversion index file
    cy.fixture(index, 'binary')
        .then((resIndex) => Cypress.Blob.binaryStringToBlob(resIndex, fileTypeXML))
        .then((blobIndex) => {
            formData.set('INDEXFILE', blobIndex, index); //adding file to formdata
        })

    //conversion data file
    cy.fixture(data, 'binary')
        .then((resData) => Cypress.Blob.binaryStringToBlob(resData, fileTypePDF))
        .then((blobData) => {
            formData.set('DATAFILE', blobData, data); //adding file to formdata
        })

    
    cy.request({
        method: method,
        url: url,
        headers: {
            Idsessionid : SessionId,
            "Content-Type": "multipart/form-data",
        },

        body: formData

    }).then((response) => {
        expect(response.status).to.eq(201);

    })

Now that I'm approaching the second and third APIs, they're very similar to the first one: the PUT request should modify the data file uploaded with the POST request and, again, it needs the three files uploaded before; and instead the the DELETE request need just a parameters-delete file that must be uploaded as a FormData to delete the data file uploaded with the POST Request.

For the PUT request I've tried again using the same code as before:

//variable name
      const param2 = 'param.xml';
      const data2 = 'data.pdf';
      const index2 = 'index.xml';

      //request datas
      const method2 = 'PUT';
      let UploadedFileID = "1A2B3C4D5E6F";
      const url2 = "https://myapi/myapi"+UploadedFileID;

      //fileType
      const fileTypeXML2 = 'application/xml';
      const fileTypePDF2 = 'application/pdf';

      //formData
      const formDataRet = new FormData();

      cy.fixture(param2, 'binary')
          .then((resParam2) => Cypress.Blob.binaryStringToBlob(resParam2, fileTypeXML2))
          .then((blobParam2) => {
              formDataRet.set('PARAMFILE', blobParam2, param2); 
          })

      cy.fixture(index2, 'binary')
          .then((resIndex2) => Cypress.Blob.binaryStringToBlob(resIndex2, fileTypeXML2))
          .then((blobIndex2) => {
              formDataRet.set('INDEXFILE', blobIndex2, index2); 
          })

      cy.fixture(data2, 'binary')
          .then((resData2) => Cypress.Blob.binaryStringToBlob(resData2, fileTypePDF2))
          .then((blobData2) => {
              formDataRet.set('DATAFILE', blobData2, data2);
          })


      cy.request({
          method: method2,
          url: url2,
          headers: {
              Idsessionid: SessionId,
              "Content-Type": "multipart/form-data",
          },

          body: formDataRet,

      }).then((response) => {
          expect(response.status).to.eq(201);


      })

However, in this case, when I change the method from POST to PUT, when Cypress sends the request, the request body it sends it's completely empty. The same happens with the DELETE request. What I receive from the APIs is a 400 - Bad Request.

I also tried to forcibly send the PUT and DELETE Request as a POST and the APIs answer with a 204, but no real changes happens to the uploaded data file.

I tried to use the following code with the DELETE Request but it doesn't work either:

        // 1. Create a new XMLHttpRequest object
    let xhr = new XMLHttpRequest();

    // 2. Configure it: GET-request for the URL /article/.../load
    xhr.open('DELETE', url);
    xhr.setRequestHeader('IdSessionid', SessionId);
    xhr.setRequestHeader("Content-Type", "multipart/form-data");

    // 3. Send the request over the network
    xhr.send(formData);

    // 4. This will be called after the response is received
    xhr.onload = function () {
        if (xhr.status != 200) { // analyze HTTP status of the response
            alert(`Error ${xhr.status}: ${xhr.statusText}`); // e.g. 404: Not Found
            cy.writeFile('cypress/fixtures/Token.txt', xhr.statusText);

        } else { // show the result
            alert(`Done, got ${xhr.response.length} bytes`); // response is the server response
        }
    };

    xhr.onprogress = function (event) {
        if (event.lengthComputable) {
            alert(`Received ${event.loaded} of ${event.total} bytes`);
        } else {
            alert(`Received ${event.loaded} bytes`); // no Content-Length
        }

    };

    xhr.onerror = function () {
        alert("Request failed");
    };

As before it sends no data to the API.

Could someone please tell me if I'm doing something wrong? Or is it just that the PUT and DELETE request with "multipart/form-data" are not supported in Cypress?

Thank you.