About

riakc_ppx is a type safe cache implementation of ocaml-riakc using ppx extensions. Keys, values, indices, and user meta data are all strongly typed for a particular riak bucket instance. It is currently a fork of ocaml-riakc, but could become dependent on it instead in the future.

Requirements

As this project requires ppx extensions, you need a recent OCaml release.

• OCaml >= 4.02.1
• bitstring
• async
• ppx_deriving_protobuf

All of the above packages can be installed via opam.

Installation

Using opam

To install riakc_ppx simply run

opam install riakc_ppx

or you can pin this repository:

opam pin add riakc_ppx --dev-repo

Building locally

The following will clone the repository, build locally, and then pin to opam:

git clone git@github.com:/struktured/riakc_ppx.git
cd riakc_ppx
omake
opam pin add riakc_ppx .

Examples

There are examples of using each API command in the example directory. There is also a minor test suite in the tests directory. The primary API entry points are Cache, Robj, and Conn.

Here's a simple run through of creating a cache using a record key type and a variant value type. All that's needed to run this is utop, a running riak server, and a valid installation of riakc_ppx:

utop # #require "riakc_ppx";;
utop # module RecordKey = struct type t = {name:string [@key 1];id:int [@key 2]} [@@deriving protobuf] end;;
module RecordKey : sig
type t = { name : bytes; id : int; }
val from_protobuf : Protobuf.Decoder.t -> t
val to_protobuf : t -> Protobuf.Encoder.t -> unit
end
utop # module VariantValue = struct type t = RED [@key 1] | GREEN [@key 2] [@@deriving protobuf] end;;
module VariantValue :
  sig
   type t = RED | GREEN
    val from_protobuf : Protobuf.Decoder.t -> t
    val from_protobuf_bare : Protobuf.Decoder.t -> t
    val to_protobuf : t -> Protobuf.Encoder.t -> unit
    val to_protobuf_bare : t -> Protobuf.Encoder.t -> unit
  end
utop # module C = Cache.Make(RecordKey)(VariantValue);;
module C : sig .. end
utop # C.with_cache ~host:"localhost" ~port:8087 ~bucket:"demo-bucket1" (fun c -> C.put c ~k:{RecordKey.name="key 1";id=123} (C.Robj.of_value (VariantValue.GREEN)));;
- : ('a C.Robj.t  RecordKey.t option, [> Opts.Put.error ]) Cache.Result.t =
    Core.Std.Result.Ok ({C.Robj.contents = []; vclock = None; unchanged = false}, None)
utop # C.with_cache ~host:"localhost" ~port:8087 ~bucket:"demo-bucket1" (fun c -> C.get c {RecordKey.name="key 1";id=123});;
- : ('a C.Robj.t, [> Opts.Get.error ]) Cache.Result.t = Core.Std.Result.Ok {C.Robj.contents =
    [{C.Robj.Content.value = VariantValue.GREEN; ... }]}

Change Log

3.0.0

• Initial public release, forked from riakc version 3.0.0

3.1.1

• Fixes compiler error with bitstring >= 2.0.4
• Better opam dependency constraints

3.1.2

• DATA FORMAT CHANGE: Internal protocol versioning (fixes issue #2)
• Fix to protobuf capable Bool module
• Added protobuf capable Float module

Contributing / Future work

Future work

• Map reduce api
• Better test suite

Contributing

• Open an issue on github
• Contact struktured on #ocaml freenode irc.