I've created a API only Phoenix framework boilerplate. Check it out on github factsfinder/phoenix_api

I notice you’re using Backblaze instead of S3. Something I also wanted to look into, can you describe that process a bit more? Is it doing a direct upload to backblaze? Or does the file pass through the server?

Sure. Using Backblaze cause b2 cloud storage is s3 compatible Low Cost, High Performance S3 Compatible Object Storage and 4 times cheaper than aws s3.

I’m not using any other server to upload files to backblaze. All the implementation is right there in the repo.

So I’m just using a combination of these libraries:

arc => GitHub - stavro/arc: 📎 Flexible file upload and attachment library for Elixir · GitHub
arc_ecto => GitHub - stavro/arc_ecto: An integration with Arc and Ecto. · GitHub

ex_aws => GitHub - ex-aws/ex_aws: A flexible, easy to use set of clients AWS APIs for Elixir · GitHub
ex_aws_s3 => GitHub - ex-aws/ex_aws_s3 · GitHub

Please note that in case of ex_aws and ex_aws_s3 I’m using forked versions that I made changes to support backblaze.
Here are forked ones that are being used right now.
https://github.com/factsfinder/ex_aws_s3
https://github.com/factsfinder/ex_aws

Pls check the lib => api => uploads => image.exs file to get a much better idea.

Let me know if you have any questions.

Does ex_aws support backblaze now? Or should I use your fork still?

It doesn’t appear so @maz, the ex_aws and ex_aws_s3 libraries only have support for the official AWS regions.

I ended up following the excellent work @factsfinder did in his original fork, just done to the latest main branch of each of these repos. If it helps for your own reference, here’s the forks:

• GitHub - chrislaskey/ex_aws_s3: ex_aws_s3 fork to support Backblaze B2 · GitHub
• GitHub - chrislaskey/ex_aws: A flexible, easy to use set of clients AWS Compatible B2 API on Backblaze for Elixir · GitHub

I use them in a Phoenix application by updating mix.exs to include:

{:ex_aws, git: "https://github.com/chrislaskey/ex_aws.git", branch: "main", override: true},
{:ex_aws_s3, git: "https://github.com/chrislaskey/ex_aws_s3.git", branch: "main"},
{:hackney, "~> 1.18"}

And in config/runtime.exs:

config :ex_aws,
  access_key_id: [System.get_env("AWS_ACCESS_KEY_ID"), :instance_role],
  secret_access_key: [System.get_env("AWS_SECRET_ACCESS_KEY"), :instance_role],
  region: System.get_env("BACKBLAZE_B2_REGION")

Where the value of BACKBLAZE_B2_REGION in my case is "us-west-001".

And as a quick sanity check things are working, I use this command to from the REPL to verify a file download from the existing B2 bucket is working:

ExAws.request(ExAws.S3.download_file("nameofmyb2bucket", "hello.txt", "world.txt"))

Note: at the time of writing, I only updated my forks to support "us-west-001" and "us-west-002". If you need other Backblaze B2 regions, you’ll need to add them following the same pattern.

Looks like it is actually possible.

I got a presigned url from backblaze using above ex_aws_s3 config