I’m trying to create a simple client for Docker that uses the unix:///var/run/docker.sock Conduit_lwt_unix.init ~src:"unix:///var/run/docker.sock" () >>= fun ctx -> let ctx = Cohttp_lwt_unix.Client.custom_ctx ~ctx () in Cohttp_lwt_unix.Client.get ~ctx (Uri.of_string "http:/version/") >>= fun (r…

According to the sources conduit uses Lwt_unix.getaddrinfo and I think this does no longer work with unix domain sockets. Please correct me if I am wrong. I have tried with "/var/run/docker.sock" but I get an empty list as well

You almost had it – just need to create a custom resolver in order to map a hostname into a Unix domain socket. There is no standard way to do this in HTTP (something has to be present in the Host field in HTTP/1.1), so we just make up a name like docker. open Lwt.Infix let t = let resolver = …

Nice stuff. This kind of examples should go straight to the documentation imho!

Excellent - thanks - those crafty Resolvers!

‘get’ works a treat, but with ‘post’ I’m still having problems. The following curl works, but the ocaml trips up with a “resolution failed: name resolution failed” - curl --unix-socket /var/run/docker.sock -H "Content-Type: application/json" \ -d '{"Image": "alpine", "Cmd": ["echo", "hello world"…

For me neither works as it is, but both are working if I replace http:/containers/create with http://docker/containers/create.

Thanks - works for me too - should have seen that!

What the custom resolver is doing here is replacing the docker part of a URI with a domain socket, so it’s important that all your URIs that connect to the Docker socket contain that particular hostname. To explain further… In a conventional name resolver such as getaddrinfo(3) , only internet addr…

Excellent news - this is a great addition - thanks Chris

How to write a simple socket-based web client (for Docker)

Learning

Chris00 October 9, 2018, 9:25am 10

You may be interested by the docker-api package (a new version should be released soon). You are welcome to submit PRs to add functions you care about.

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How to write a simple socket-based web client (for Docker)

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