send image to google vision endpoint

googleVisionRequest.js

   // Get an image dataURL from the canvas.
    var imageDataURL = hidden_canvas.toDataURL('image/png');
    var courseLang = document.querySelector('#courseLanguage').value;
    return fetch(url, {
        method: "POST",
        headers: {
            'Content-Type': 'application/json'
        },
        body: JSON.stringify({ img: imageDataURL, courseLang: courseLang })
    }).then(response => response.json())
        .then(response => {
            const listLabels = response && response.map((word) => {
                return `<div>${word.courseLang} ( ${word.text})</div>`
            }).join('');
            labels.innerHTML = `<label><h2> You pointed at: </h2> </label>
                    <div class='words-list'>${listLabels}</div>`;
    });