Hi @robbat2, the pre-signed URL is going to be used for directly uploading file content of images.

Was trying to make a URL that did not need the content-type, but found out yesterday that the content-type was all that was missing in the PUT request.

So this azure function code works:

module.exports = async function (context, req) {
    const aws = require('aws-sdk');

    var signedURL;

    let DO_ENDPOINT = req.body.do_endpoint;
    let DO_ACCESS_KEY_ID = req.body.access_key;
    let DO_SECRET_ACCESS_KEY = req.body.secret_key;
    let DO_SPACE = req.body.bucket;
    let DO_GUID = req.body.key;

    const spacesEndpoint = new aws.Endpoint(DO_ENDPOINT);
    const s3 = new aws.S3({
        endpoint: spacesEndpoint,
        accessKeyId: DO_ACCESS_KEY_ID,
        secretAccessKey: DO_SECRET_ACCESS_KEY,
    });

    const s3Params = {
        Bucket: DO_SPACE,
        Key: DO_GUID,
        ContentType: 'image/jpeg',
        ACL: 'public-read',
        Expires: 600,
    };

    s3.getSignedUrl('putObject', s3Params, function (err, url) {
        if (err) {
            context.res = {
                status: 400,
                body: "Something went wrong, please try again."
            };
        } else {
            context.res = {
                body: url
            };
        }
    });
};

Only thing that needs to be added is the headers in the PUT request:

x-amz-acl:public-read
Content-Type:image/jpeg

Current code is for .jpeg file and needs to be passed the MIME type if its going to be used for something else.