I am using the fabricjs package and want to make use of the fabric.Image.fromURL function. The documentation for this function is below:
(static)
fromURL(url, callbackopt, imgOptionsopt)Creates an instance of
fabric.Imagefrom an URL string
Parameters:
Name Type Attributes Description url String URL to create an image from callback function <optional> Callback to invoke when image is created (newly created image is passed as a first argument). Second argument is a boolean indicating if an error occurred or not. imgOptions Object <optional> Options object
I would to refactor my code to use modern Promise notation instead of nesting callbacks. Can I refactor this function into a Promise?
Currently if I want to add two images in a row, my code looks like this:
# add first image
fabric.Image.fromURL(url1, function (oImg: any) {
canvas.add(oImg);
# add second image
fabric.Image.fromURL(url2, function (oImg: any) {
canvas.add(oImg);
}
})
I would love to be able to rewrite it as
async def addImages() {
await promisifiedImageFromURL(url1)
await promisifiedImageFromURL(url2)
}
I have looked into util.promisify (https://nodejs.org/api/util.html#utilpromisifyoriginal) but this function expects the corresponding function to be in a specific format: a single error-first callback. The fromURL function, on the other hand, is in a nonstandard format, which is where I am having trouble
I'm looking into custom promisified functions, but I'm honestly in over my head here
const promiseFromUrl = (url, imgOptions) => {
return new Promise((res, rej) => {
const callback = (image, isError) => {
if (isError) rej(new Error('Some error occurred'));
else res(image);
};
fromURL(url, callback, imageOptions);
});
}