First tests - upload to B2 from the server seems ok with ExAws.S3

[ndrean]

You can set up a bucket in B2 quite simply. I did not do anything special. And it seems directly compatible with ExAws.S3🎉

In place of the S3 config, I did:

config :ex_aws, :s3,
  debug_requests: true,
  access_key_id: System.get_env("B2_KEY_ID"),
  secret_access_key: System.get_env("B2_KEY_SECRET"),
  host: s3.eu-central-003.backblazeb2.com,
  bucket: up-image

The key point is to use host and not pass the region in the config. Then ExAws will automatically read this config for you.

host = s3.<b2_region><dns_suffix>

To use this, I have a browser tab opened serving a form with a file input (but you could curl -F ....). On submit, I POST the form to a controller. In the Phoenix code, you can use directly ExAws.S3.Upload and this can do multipart with zero efforts, the "standard" code (without XML parsing).

def handle_b2(conn, params) do
...

path
|> ExAws.S3.Upload.stream_file()
|> ExAws.S3.upload("up-image"), URI.encode(filename),
  acl: :public_read,
  content_type: mime,
  content_disposition: "inline"
)
|> ExAws.request()

This uploads the file. The details are:

and it serves the uploaded file at: https://f003.backblazeb2.com/file/up-image/5ooil3d759vq8ng8hg0c.png

Seems slower than S3 but so far so good! ✌️

Next step: B2 -> Cloudfare CDN. For this, I need to create a domain on Cloudfare to cache the B2 bucket on the CDN.

https://www.backblaze.com/docs/cloud-storage-deliver-private-backblaze-b2-content-through-cloudflare-cdn

Public bucket: https://www.backblaze.com/docs/cloud-storage-deliver-public-backblaze-b2-content-through-cloudflare-cdn