flask-s3-multipart

This is a sample project to demonstrate how to upload directly to Amazon S3 via CORS using Flask making use of the multipart upload REST API.

The uploaded file will be chunked and sent to S3 concurrently. Every failed Ajax request will be retried until successful.

Using

Make sure the permission and CORS configuration of your S3 bucket are set properly.
Fill in these values in app.py:
- AWS_ACCESS_KEY_ID
- AWS_SECRET_KEY
- S3_BUCKET_NAME
Run app.py as usual.

python app.py

Sample CORS Configuration

Sample CORS configuration to enable CORS API:

<?xml version="1.0" encoding="UTF-8"?>
<CORSConfiguration xmlns="http://s3.amazonaws.com/doc/2006-03-01/">
    <CORSRule>
        <AllowedOrigin>*</AllowedOrigin>
        <AllowedMethod>GET</AllowedMethod>
        <AllowedMethod>POST</AllowedMethod>
        <AllowedMethod>PUT</AllowedMethod>
        <MaxAgeSeconds>3000</MaxAgeSeconds>
        <ExposeHeader>ETag</ExposeHeader>
        <AllowedHeader>*</AllowedHeader>
        <AllowedHeader>Access-Control-Expose-Headers</AllowedHeader>
    </CORSRule>
</CORSConfiguration>

Note the * in the AllowedOrigin which means that any domain is allowed to use the CORS API. Be sure to change it.

Sample Bucket Policy

Sample bucket policy to enable everyone to download objects from the bucket:

{
    "Version": "2008-10-17",
    "Id": "Policy1378976564974",
    "Statement": [
        {
            "Sid": "Stmt1378976561483",
            "Effect": "Allow",
            "Principal": {
                "AWS": "*"
            },
            "Action": "s3:GetObject",
            "Resource": "arn:aws:s3:::your-bucket-name/\*"
        }
    ]
}

Useful Docs

Amazon: Multipart Upload Overview

Amazon: API Support for Multipart Upload

Amazon: Signing and Authenticating REST Requests

Amazon: Enabling Cross-Origin Resource Sharing

Useful References

mule-uploader