From 60e9541a7062fa8538148c643cc38fe6096683e2 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Reynir=20Bj=C3=B6rnsson?= <reynir@reynir.dk>
Date: Wed, 15 Nov 2023 17:01:28 +0100
Subject: [PATCH] Use a custom git commit message

Requires yocaml#76b27c6282ff343e618f53c03153008a7ee2366e or later.
---
 src/blogger.ml | 18 +++++++++++++++++-
 1 file changed, 17 insertions(+), 1 deletion(-)

diff --git a/src/blogger.ml b/src/blogger.ml
index 71d6524..ca1edf7 100644
--- a/src/blogger.ml
+++ b/src/blogger.ml
@@ -125,6 +125,20 @@ let run_git_config key = function
       | Ok (value, _) -> Some value
       | Error _ -> None)
 
+let run_git_rev_parse default =
+  let open Bos in
+  let value = OS.Cmd.run_out Cmd.(v "git" % "rev-parse" % "HEAD") in
+  match OS.Cmd.out_string value with
+  | Ok (value, (_, `Exited 0)) -> value
+  | Ok (value, (run_info, _)) ->
+    Logs.warn (fun m -> m "Failed to get commit id: %a: %s"
+                  Cmd.pp (OS.Cmd.run_info_cmd run_info)
+                  value);
+    default
+  | Error `Msg e ->
+    Logs.warn (fun m -> m "Failed to get commit id: %s" e);
+    default
+
 let get_name_and_email name email =
   let name = run_git_config "user.name" name in
   let email = run_git_config "user.email" email in
@@ -144,12 +158,14 @@ let name_and_email =
 let build_and_push _quiet remote (author, email) hook =
   let fiber () =
     let open Lwt.Syntax in
+    let commit_id = run_git_rev_parse "an unknown state" in
+    let comment = Printf.sprintf "Built from %s" commit_id in
     let* ctx = unix_ctx_with_ssh () in
     let* res =
       Yocaml_git.execute
         (module Yocaml_unix)
         (module Pclock)
-        ~ctx ?author ?email remote (program ~target:"")
+        ~ctx ?author ?email ~comment remote (program ~target:"")
     in
     match res with
     | Error (`Msg err) -> Fmt.failwith "build-and-push: %s." err