Handling Binary File Uploads

Hi,

I have a protobuf that defines one field

message FileUpload { bytes fileContents = 1; }

I want to be able to upload a file, and have the contents of that upload stored in fileContents. When sending json data, I understand that the keys map to grpc message fields. But in the case of a binary upload there is no field name, so how can I map the contents of the request body into a message?

rpc UploadFile(FileUpload) returns (google.protobuf.Empty)) {
    option (google.api.http) = {
        post: "/v1/files"
        body: "*"
    };
}

If I use curl to make a request like this: curl -X POST --data-binary "@/tmp/test_file.txt" http://localhost:9090/v1/files

The HTTP request looks like this:

POST /v1/cmd/secretfiles HTTP/1.1
Host: localhost:9090
User-Agent: curl/7.54.0
Accept: */*
Content-Length: 1675
Content-Type: application/x-www-form-urlencoded
Expect: 100-continue

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