We're working on a flutter app where we want to upload single large files (100-150 MBs) directly to S3. The upload is too slow for our use case even though we're sending contentType: 'multipart/form-data'. We've looked through AWS docs and found out that we should be using multipart upload.
Now the problem is doesn't contentType: 'multipart/form-data' ensure that the file will be uploaded in chunks? If it doesn't, how can we break the file into parts at frontend using flutter and upload all of them to S3? (we're using Dio as our HttpClient)
Please help us to solve this problem.