.github/workflows/format.yml

@@ -1,17 +1,28 @@
 name: format
 
 on:
+  pull_request:
   push:
     branches:
       - main
-  pull_request:
 
 jobs:
   format:
     name: format
+    strategy:
+      matrix:
+        ocaml-compiler:
+            - '5.3'
     runs-on: 'ubuntu-latest'
-    container: ghcr.io/c-cube/c-cube-commmon/ci-doc-5.3:latest
     steps:
-      - uses: actions/checkout@v6
+      - uses: actions/checkout@main
+      - name: Use OCaml ${{ matrix.ocaml-compiler }}
+        uses: ocaml/setup-ocaml@v3
+        with:
+          ocaml-compiler: ${{ matrix.ocaml-compiler }}
+          dune-cache: true
+          allow-prerelease-opam: true
+
+      - run: opam install ocamlformat.0.27.0
       - run: opam exec -- make format-check
 

.github/workflows/gh-pages.yml

@@ -11,19 +11,26 @@ jobs:
     runs-on: ubuntu-latest
     permissions:
       contents: write
-    container: ghcr.io/c-cube/c-cube-commmon/ci-doc-5.3:latest
     steps:
-      - uses: actions/checkout@v6
+      - uses: actions/checkout@main
 
-      - run: opam pin .#HEAD -y -n
+      - name: Use OCaml
+        uses: ocaml/setup-ocaml@v3
+        with:
+          ocaml-compiler: '5.1.x'
+          allow-prerelease-opam: true
+          dune-cache: true
+
+      - run: opam pin odoc 3.1.0 -y -n
+        # crash with 2.4, see https://github.com/ocaml/odoc/issues/1066
       - name: Deps
-        run: opam install thread-local-storage lwt trace trace-tef trace-fuchsia ppx_trace
+        run: opam install odig thread-local-storage trace trace-tef trace-fuchsia ppx_trace
 
       - name: Build
         run: opam exec -- odig odoc --cache-dir=_doc/ trace trace-tef trace-fuchsia ppx_trace
 
       - name: Deploy
-        uses: peaceiris/actions-gh-pages@v4
+        uses: peaceiris/actions-gh-pages@v3
         with:
           github_token: ${{ secrets.GITHUB_TOKEN }}
           publish_dir: ./_doc/html

.github/workflows/main.yml

@@ -1,4 +1,4 @@
-name: build
+name: Build and Test
 
 on:
   push:
@@ -8,21 +8,28 @@ on:
 
 jobs:
   run:
-    name: build  # build+test on various versions of OCaml, on linux
-    timeout-minutes: 15
+    name: build
     strategy:
       fail-fast: true
       matrix:
-        container:
-          - ghcr.io/c-cube/c-cube-commmon/ci-4.08:latest
-          - ghcr.io/c-cube/c-cube-commmon/ci-4.14:latest
-          - ghcr.io/c-cube/c-cube-commmon/ci-5.0:latest
-          - ghcr.io/c-cube/c-cube-commmon/ci-5.4:latest
+        os:
+            - ubuntu-latest
+              #- macos-latest
+              #- windows-latest
+        ocaml-compiler:
+            - '4.08.x'
+            - '4.14.x'
+            - '5.3.x'
 
-    runs-on: ubuntu-latest
-    container: ${{ matrix.container }}
+    runs-on: ${{ matrix.os }}
     steps:
-      - uses: actions/checkout@v6
+      - uses: actions/checkout@main
+      - name: Use OCaml ${{ matrix.ocaml-compiler }}
+        uses: ocaml/setup-ocaml@v3
+        with:
+          ocaml-compiler: ${{ matrix.ocaml-compiler }}
+          dune-cache: true
+          allow-prerelease-opam: true
 
       # check that trace compiles with no optional deps
       - run: opam install -t trace --deps-only
@@ -30,16 +37,24 @@ jobs:
 
       # install all packages
       - run: opam install -t trace trace-tef trace-fuchsia --deps-only
-      - run: opam install ppx_trace --deps-only
-        if: ${{ !contains(matrix.container, 'ci-4.08') }}
+      - run: opam install ppx_trace --deps-only # no tests
+        if: matrix.ocaml-compiler != '4.08.x'
       - run: opam exec -- dune build '@install' -p trace,trace-tef,trace-fuchsia
       - run: opam exec -- dune build '@install' -p ppx_trace
-        if: ${{ !contains(matrix.container, 'ci-4.08') }}
+        if: matrix.ocaml-compiler != '4.08.x'
       - run: opam exec -- dune runtest -p trace
       - run: opam install trace
       - run: opam exec -- dune runtest -p trace-tef,trace-fuchsia
 
       # with depopts
-      - run: opam install thread-local-storage lwt mtime
+      - run: opam install hmap thread-local-storage
       - run: opam exec -- dune build '@install' -p trace,trace-tef,trace-fuchsia
-      - run: opam exec -- dune runtest -p trace,trace-tef,trace-fuchsia
+
+      - run: opam install picos_aux
+        if: matrix.ocaml-compiler != '4.08.x' && matrix.ocaml-compiler != '4.12.x'
+      - run: opam exec -- dune build '@install' -p trace,trace-tef,trace-fuchsia
+        if: matrix.ocaml-compiler != '4.08.x' && matrix.ocaml-compiler != '4.12.x'
+
+      - run: opam install mtime
+      - run: opam exec -- dune build '@install' -p trace,trace-tef,trace-fuchsia
+

dune-project

@@ -22,14 +22,13 @@
  (synopsis
   "A lightweight stub for tracing/observability, agnostic in how data is collected")
  (description
-  "ocaml-trace can be used to instrument libraries and programs with low overhead. It doesn't do any IO unless a collector is plugged in, which only the final executable should do.")
+  "ocaml-trace can be used to instrument libraries and programs with low overhead.\n\n              It doesn't do any IO unless a collector is plugged in, which only\n              the final executable should do.")
  (depends
   (ocaml
    (>= 4.08))
   dune)
  (depopts
   unix
-  lwt
   (thread-local-storage (>= 0.2))
   (mtime
    (>= 2.0)))

src/lwt/dune

@@ -1,6 +0,0 @@
-(library
- (name trace_lwt)
- (public_name trace.lwt)
- (optional) ; lwt
- (libraries trace.core lwt)
- (synopsis "Interface with lwt"))

src/lwt/trace_lwt.ml

@@ -1,50 +0,0 @@
-(** Optional interface with lwt.
-
-    This provides a Lwt-friendly variant of {!Trace_core.with_span}.
-
-    To track the ambient span, which can be useful for some backends or for
-    async spans, you can use [Ambient_context_lwt], a collector-specific ambient
-    span provider (eg [Opentelemetry_trace] comes with one), or define your own
-    like this:
-
-    {[
-      (* new key to track the current span in lwt context *)
-      let k_ambient_span : Trace_core.span Lwt.key = Lwt.new_key ()
-
-      (* ambient span provider, install it using Trace_core.set_ambient_context_provider] *)
-      let ambient_span_provider : Trace_core.Ambient_span_provider.t =
-        ASP_some
-          ( (),
-            {
-              get_current_span = (fun () -> Lwt.get k_ambient_span);
-              with_current_span_set_to =
-                (fun () span f ->
-                  Lwt.with_value k_ambient_span (Some span) (fun () -> f span));
-            } )
-    ]}
-
-    @since NEXT_RELEASE *)
-
-open Trace_core
-
-(** [with_span name f] enters a span [sp], calls [f sp] which returns a Lwt
-    promise, and make sure to exit the span [sp] when [f sp] exits (or fails).
-
-    This is similar to {!Trace_core.with_span} but it respects the promise
-    semnatics of Lwt (ie. it doesn't exit the span immediately instead of
-    waiting for the promise to end).
-
-    To track the current span you still need to install a Lwt-friendly
-    {!Trace_core.Ambient_span_provider.t} (probably using {!Lwt.with_value}). *)
-let with_span ?level ?__FUNCTION__ ~__FILE__ ~__LINE__ ?parent ?params ?data
-    name (f : span -> 'a Lwt.t) : 'a Lwt.t =
-  if Trace_core.enabled () then (
-    let span =
-      Trace_core.enter_span ?level ?__FUNCTION__ ~__FILE__ ~__LINE__ ?parent
-        ?params ?data name
-    in
-    let fut = Trace_core.with_current_span_set_to span f in
-    Lwt.on_termination fut (fun () -> Trace_core.exit_span span);
-    fut
-  ) else
-    f Trace_core.Collector.dummy_span

test/common/dune

@@ -1,3 +0,0 @@
-(library
- (name test_trace_common)
- (libraries trace.core))

test/common/test_trace_common.ml

@@ -1,32 +0,0 @@
-(** Shared test utilities for ambient span tests. *)
-
-type Trace_core.span += Named of string
-
-let make_recorder () =
-  let open Trace_core.Collector in
-  let cbs =
-    Callbacks.make
-      ~enter_span:(fun
-          ()
-          ~__FUNCTION__:_
-          ~__FILE__:_
-          ~__LINE__:_
-          ~level:_
-          ~params:_
-          ~data:_
-          ~parent:_
-          name
-        -> Named name)
-      ~exit_span:(fun () _sp -> ())
-      ~add_data_to_span:(fun () _sp _data -> ())
-      ~message:(fun () ~level:_ ~params:_ ~data:_ ~span:_ _msg -> ())
-      ~metric:(fun () ~level:_ ~params:_ ~data:_ _name _m -> ())
-      ()
-  in
-  C_some ((), cbs)
-
-let current_name () =
-  match Trace_core.current_span () with
-  | None -> "none"
-  | Some (Named s) -> s
-  | Some _ -> "<other>"

test/lwt/dune

@@ -1,21 +0,0 @@
-(executable
- (name t_lwt)
- (modules t_lwt)
- (libraries
-  trace
-  test_trace_common
-  (select
-   t_lwt.ml
-   from
-   (trace.lwt lwt.unix -> t_lwt.real.ml)
-   (-> t_lwt.quine.ml))))
-
-(rule
- (alias runtest)
- (package trace)
- (action
-  (progn
-   (with-stdout-to
-    t_lwt.output
-    (run %{exe:t_lwt.exe} %{dep:t_lwt.expected}))
-   (diff t_lwt.expected t_lwt.output))))

test/lwt/t_lwt.expected

@@ -1,10 +0,0 @@
-=== ambient span (Lwt) ===
-before any span: none
-sync outer: sync-outer
-sync inner: sync-inner
-after sync: none
-lwt outer: lwt-outer
-lwt inner: lwt-inner
-after lwt inner: lwt-outer
-after lwt outer: none
-after binds: bind-test

test/lwt/t_lwt.quine.ml

@@ -1,10 +0,0 @@
-(* When trace.lwt is unavailable, echo the expected file
-   so the diff always passes. The file is passed as argv[1] by the dune rule. *)
-let () =
-  let ic = open_in Sys.argv.(1) in
-  (try
-     while true do
-       print_char (input_char ic)
-     done
-   with End_of_file -> ());
-  close_in ic

test/lwt/t_lwt.real.ml

@@ -1,60 +0,0 @@
-(* Test ambient span tracking via Lwt key provider *)
-
-open Test_trace_common
-
-let ( let@ ) = ( @@ )
-let k_ambient_span : Trace_core.span Lwt.key = Lwt.new_key ()
-
-let ambient_span_provider : Trace_core.Ambient_span_provider.t =
-  ASP_some
-    ( (),
-      {
-        get_current_span = (fun () -> Lwt.get k_ambient_span);
-        with_current_span_set_to =
-          (fun () span f ->
-            Lwt.with_value k_ambient_span (Some span) (fun () -> f span));
-      } )
-
-let () =
-  print_endline "=== ambient span (Lwt) ===";
-  Trace_core.set_ambient_context_provider ambient_span_provider;
-  let coll = make_recorder () in
-  let@ () = Trace_core.with_setup_collector coll in
-
-  (* sync with_span works with the Lwt provider *)
-  Printf.printf "before any span: %s\n" (current_name ());
-
-  (let@ _outer = Trace_core.with_span ~__FILE__ ~__LINE__ "sync-outer" in
-   Printf.printf "sync outer: %s\n" (current_name ());
-   let@ _inner = Trace_core.with_span ~__FILE__ ~__LINE__ "sync-inner" in
-   Printf.printf "sync inner: %s\n" (current_name ()));
-
-  Printf.printf "after sync: %s\n" (current_name ());
-
-  (* Lwt-specific tests *)
-  Lwt_main.run
-    (let open Lwt.Syntax in
-     (* nested Trace_lwt.with_span *)
-     let* () =
-       Trace_lwt.with_span ~__FILE__ ~__LINE__ "lwt-outer" (fun _outer ->
-           Printf.printf "lwt outer: %s\n" (current_name ());
-           let* () =
-             Trace_lwt.with_span ~__FILE__ ~__LINE__ "lwt-inner" (fun _inner ->
-                 Printf.printf "lwt inner: %s\n" (current_name ());
-                 Lwt.return_unit)
-           in
-           Printf.printf "after lwt inner: %s\n" (current_name ());
-           Lwt.return_unit)
-     in
-     Printf.printf "after lwt outer: %s\n" (current_name ());
-
-     (* context survives Lwt.bind chain *)
-     let* () =
-       Trace_lwt.with_span ~__FILE__ ~__LINE__ "bind-test" (fun _sp ->
-           let* () = Lwt.return_unit in
-           let* () = Lwt.return_unit in
-           Printf.printf "after binds: %s\n" (current_name ());
-           Lwt.return_unit)
-     in
-
-     Lwt.return_unit)

test/tls/dune

@@ -3,7 +3,8 @@
  (modules t_tls)
  (libraries
   trace
-  test_trace_common
+  ; avoid using a recent dune with `enabled-if`, by just using `select` instead.
+  ; the dummy case just echoes back the expected file.
   (select
    t_tls.ml
    from

test/tls/t_tls.real.ml

@@ -1,9 +1,39 @@
 (* Test ambient span tracking via thread-local-storage provider *)
 
-open Test_trace_common
-
 let ( let@ ) = ( @@ )
 
+(* Unique span type so we can identify spans by name *)
+type Trace_core.span += Named of string
+
+let make_recorder () =
+  let open Trace_core.Collector in
+  let cbs =
+    Callbacks.make
+      ~enter_span:(fun
+          ()
+          ~__FUNCTION__:_
+          ~__FILE__:_
+          ~__LINE__:_
+          ~level:_
+          ~params:_
+          ~data:_
+          ~parent:_
+          name
+        -> Named name)
+      ~exit_span:(fun () _sp -> ())
+      ~add_data_to_span:(fun () _sp _data -> ())
+      ~message:(fun () ~level:_ ~params:_ ~data:_ ~span:_ _msg -> ())
+      ~metric:(fun () ~level:_ ~params:_ ~data:_ _name _m -> ())
+      ()
+  in
+  C_some ((), cbs)
+
+let current_name () =
+  match Trace_core.current_span () with
+  | None -> "none"
+  | Some (Named s) -> s
+  | Some _ -> "<other>"
+
 let () =
   print_endline "=== ambient span (TLS) ===";
   Trace_thread_local_storage.setup ();

trace.opam

@@ -3,8 +3,11 @@ opam-version: "2.0"
 version: "0.12"
 synopsis:
   "A lightweight stub for tracing/observability, agnostic in how data is collected"
-description:
-  "ocaml-trace can be used to instrument libraries and programs with low overhead. It doesn't do any IO unless a collector is plugged in, which only the final executable should do."
+description: """
+ocaml-trace can be used to instrument libraries and programs with low overhead.
+
+              It doesn't do any IO unless a collector is plugged in, which only
+              the final executable should do."""
 maintainer: ["Simon Cruanes"]
 authors: ["Simon Cruanes"]
 license: "MIT"
@@ -18,7 +21,6 @@ depends: [
 ]
 depopts: [
   "unix"
-  "lwt"
   "thread-local-storage" {>= "0.2"}
   "mtime" {>= "2.0"}
 ]