Add ipmi support

Author: patricoferris

.gitmodules

@@ -1,3 +0,0 @@
-[submodule "ocaml-variorum"]
-	path = ocaml-variorum
-	url = https://github.com/patricoferris/ocaml-variorum

clarke.opam

@@ -11,8 +11,15 @@ doc: "https://patricoferris.github.io/clarke/"
 build: ["dune" "build" "-p" name "-j" jobs]
 depends: [
   "dune" {>= "2.0"}
-  "eio_main" {>= "0.5"}
+  "eio_luv"
   "variorum"
   "ptime"
   "cmdliner"
-]
+]
+pin-depends: [
+  [ "hwloc.dev" "git+https://github.com/patricoferris/ocaml-hwloc#3447dc5c40f0d868529aafcc84b5d2d971062b30" ]
+  [ "jansson.dev" "git+https://github.com/patricoferris/ocaml-jansson#42cb429e722ec64807d75ae401758eb666c9d189" ]
+  [ "eio.dev" "git+https://github.com/patricoferris/eio#e22946a7e8de7094f15753cc9084beb1c06dd43b" ]
+  [ "eio_luv.dev" "git+https://github.com/patricoferris/eio#e22946a7e8de7094f15753cc9084beb1c06dd43b" ]
+  [ "variorum.dev" "git+https://github.com/patricoferris/ocaml-variorum#9128770e9df08ca7a90f317acc08b9cd49da6766" ]
+]

dune

@@ -1 +1 @@
-(vendored_dirs ocaml-variorum ocaml-ipmi)
+(vendored_dirs ocaml-variorum eio)

ocaml-variorum

@@ -43,11 +43,13 @@ module Specs = struct
 
   let meter_of_meter_spec ~clock = function
     | `Const f -> Models.const ~clock f
+    | `Ipmi -> S.Meter ((module Clarke.Ipmi), { clock })
     | `Variorum -> S.Meter ((module Clarke.Variorum), { clock })
 
   let meter_spec_of_string s =
     match String.lowercase_ascii s with
     | "variorum" -> Ok `Variorum
+    | "ipmi" -> Ok `Ipmi
     | v -> (
         match String.split_on_char ':' v with
         | [ "const"; f ] -> (

src/bin/main.ml

@@ -1,4 +1,4 @@
 (library
  (name clarke)
  (public_name clarke)
- (libraries eio ptime variorum ezjsonm))
+ (libraries eio_luv eio.unix ptime variorum ezjsonm))

src/lib/dune

@@ -0,0 +1,47 @@
+(* Ipmi-based monitor *)
+open Eio
+open Eio_luv.Low_level
+
+module Ipmi = struct
+  let ipmi args = ("sudo", "sudo" :: "ipmitool" :: args)
+  let power_consumption = ipmi [ "sensor"; "reading"; "Pwr Consumption"; "-c" ]
+
+  let parse_power_consumption s =
+    match String.split_on_char ',' (String.trim s) with
+    | "Pwr Consumption" :: watts :: _ -> int_of_string watts
+    | _ -> failwith "Couldn't parse the power consumption"
+end
+
+type t = { clock : Eio.Time.clock }
+
+let supported = true
+
+let read_all handle buf =
+  let rec read acc =
+    try
+      let i = Eio_luv.Low_level.Stream.read_into handle buf in
+      read (acc + i)
+    with End_of_file -> acc
+  in
+  read 0
+
+let get_power_consumption () =
+  let cmd, args = Ipmi.power_consumption in
+  let parent_pipe = Eio_luv.Low_level.Pipe.init () in
+  Switch.run @@ fun sw ->
+  let handle = Eio_luv.Low_level.Pipe.to_handle ~sw parent_pipe in
+  let buf = Luv.Buffer.create 64 in
+  let redirect =
+    Eio_luv.Low_level.Process.
+      [ to_parent_pipe ~fd:Luv.Process.stdout ~parent_pipe () ]
+  in
+  let t = Process.spawn ~redirect cmd args in
+  let _ = Process.await_exit t in
+  let read = read_all handle buf in
+  Luv.Buffer.to_string (Luv.Buffer.sub buf ~offset:0 ~length:read)
+
+let collect t =
+  let pc =
+    get_power_consumption () |> Ipmi.parse_power_consumption |> float_of_int
+  in
+  Info.v (Option.get (Ptime.of_float_s @@ Time.now t.clock)) pc