OCaml Gremlin Client

Overview

This is a very rough Apache Tinkerpop3 Gremlin client library written in OCaml. It was implemented using the Graph Driver Provider Requirements.

Given this is my first public OCaml library and I was fairly rushed, it's not pretty.

I'd like to improve it which probably means completely refactoring it but I'm not sure when I'll get the chance. In the meantime, any suggestions or PRs are welcome.

Instructions

Build/Install

git clone https://github.com/bramford/ocaml-gremlin
cd ocaml-gremlin
opam pin add .

Usage

Assuming you're running a gremlin server on localhost:8182, in a toplevel such as utop:

#require "gremlin";;

let conn =
    Gremlin.Websocket.new_connection
    (Uri.of_string "http://localhost:8182/gremlin")

(* Add vertices *)
let add_vertices = Lwt_main.run (
  Gremlin.Websocket.run_queries_transaction
    conn
    ["g.addV('user').property('name', 'foo')";
    "g.addV('user').property('name', 'bar')";]
)

(* Get vertices *)
let get_vertices =
  Lwt_main.run (
    Gremlin.Websocket.run_query
      conn
      "g.V()"
  )
;;

See examples/ for other examples.

To do

There's obviously a lot to improve but here are some starting points:

• Properly close gremlin session on completion
• Handle streamed responses
• Add interface documentation (e.g. odoc)
• Implement proper logging (e.g. using Logs)
• Improve types and results
• Abstract internals and types properly
• Refactor/improve response handler (currently uses Lwt_stream but poorly)
• Refactor response JSON checking/parsing
• Improve concurrency (currently all serial using Lwt_list.map_s)
• Support other serialization formats (e.g. bytecode)
• Support Traversal OpProcessor
• Support REST interface
• MirageOS compatibility