Arc ecto image fetch from aws s3

[ghost]

I am not sure whether this is a arc or arc_ecto or ex_aws issue, when I upload the image that works fine I guess, at least there are no errors. now while fetching the image like this MyApp.Avatar.url({ user.photo, user}, :thumb, signed: true)

it throws this error:

<Error>
  <Code>SignatureDoesNotMatch</Code>
  <Message>
    The request signature we calculated does not match the signature you provided. Check your key and signing method.
  </Message>
  <AWSAccessKeyId>ACCESSID</AWSAccessKeyId>
  <StringToSign>
    AWS4-HMAC-SHA256 20160613T132235Z 20160613/us-east-1/s3/aws4_request 3119114
  </StringToSign>
  <SignatureProvided>
    f1e2764695
  </SignatureProvided>
  <StringToSignBytes>
     stuff
  </StringToSignBytes>
  <CanonicalRequest>
    GET /memento-is-dev/uploads/Screenshot%20from%202016-05-24%2014%3A43%3A13.png X-Amz-Algorithm=AWS4-HMAC-SHA256&X-Amz-Credential=ACCESS%2F20160613%2Fus-east-1%2Fs3%2Faws4_request&X-Amz-Date=20160613T131355Z&X-Amz-Expires=300&X-Amz-SignedHeaders=host&v=63633027268 host:s3.amazonaws.com host UNSIGNED-PAYLOAD
  </CanonicalRequest>
  <CanonicalRequestBytes>
    stuff
  </CanonicalRequestBytes>
  <HostId>
    fjO3c4Y=
  </HostId>
</Error>

I am using ecto 1.x with arc_ecto 0.3.2 and arc 0.5

here is some code in the controller to insert an image:

    case Repo.insert(changeset) do
      {:ok, prof} ->
        IO.inspect prof
        Expense.Avatar.store({transaction_params["image"], prof})

        conn
        |> put_flash(:info, "Profile created successfully")
        |> redirect(to: user_profile_path(conn, :index, user_id))
      {:error, changeset} ->
        render(conn, "index.html", changeset: changeset)
    end

[tiagoengel]

I'm getting this problem too, this is because of the v (version) query parameter that is added to the url. According to the aws documentation every query parameter and header should be used to calculate the signature.

I don't really see the point of adding this parameter for signed urls, I think it could be removed when the option signed is true. If there's a reason to keep it, it should be passed along to ex_aws in some way.

As a workaround I'm manually removing this parameter from the url for now

urls_with_version = ProjectImage.urls({image, project}, signed: true)

Enum.reduce(urls_with_version, %{}, fn ({key, value}, acc) ->
  Map.put(acc, key, String.replace(value, ~r/&v=(.*)$/, ""))
end)

[stavro]

Thanks for investigating!