Merge pull request #22 from imandra-ai/wip-format

format

dune

@@ -1,3 +1,3 @@
-
 (env
-  (_ (flags :standard -warn-error -a+8)))
+ (_
+  (flags :standard -warn-error -a+8)))

src/atomic/atomic.post412.mli

@@ -1,4 +1,3 @@
-
 (**************************************************************************)
 (*                                                                        *)
 (*                                 OCaml                                  *)
@@ -19,34 +18,34 @@
 (** Atomic references.
 *)
 
-(** An atomic (mutable) reference to a value of type ['a]. *)
 type 'a t = 'a Stdlib.Atomic.t
+(** An atomic (mutable) reference to a value of type ['a]. *)
 
-(** Create an atomic reference. *)
 val make : 'a -> 'a t
+(** Create an atomic reference. *)
 
-(** Get the current value of the atomic reference. *)
 val get : 'a t -> 'a
+(** Get the current value of the atomic reference. *)
 
-(** Set a new value for the atomic reference. *)
 val set : 'a t -> 'a -> unit
+(** Set a new value for the atomic reference. *)
 
-(** Set a new value for the atomic reference, and return the current value. *)
 val exchange : 'a t -> 'a -> 'a
+(** Set a new value for the atomic reference, and return the current value. *)
 
+val compare_and_set : 'a t -> 'a -> 'a -> bool
 (** [compare_and_set r seen v] sets the new value of [r] to [v] only
     if its current value is physically equal to [seen] -- the
     comparison and the set occur atomically. Returns [true] if the
     comparison succeeded (so the set happened) and [false]
     otherwise. *)
-val compare_and_set : 'a t -> 'a -> 'a -> bool
 
+val fetch_and_add : int t -> int -> int
 (** [fetch_and_add r n] atomically increments the value of [r] by [n],
     and returns the current value (before the increment). *)
-val fetch_and_add : int t -> int -> int
 
-(** [incr r] atomically increments the value of [r] by [1]. *)
 val incr : int t -> unit
+(** [incr r] atomically increments the value of [r] by [1]. *)
 
-(** [decr r] atomically decrements the value of [r] by [1]. *)
 val decr : int t -> unit
+(** [decr r] atomically decrements the value of [r] by [1]. *)

src/atomic/atomic.pre412.mli

@@ -1,4 +1,3 @@
-
 (**************************************************************************)
 (*                                                                        *)
 (*                                 OCaml                                  *)
@@ -19,34 +18,34 @@
 (** Atomic references.
 *)
 
-(** An atomic (mutable) reference to a value of type ['a]. *)
 type 'a t
+(** An atomic (mutable) reference to a value of type ['a]. *)
 
-(** Create an atomic reference. *)
 val make : 'a -> 'a t
+(** Create an atomic reference. *)
 
-(** Get the current value of the atomic reference. *)
 val get : 'a t -> 'a
+(** Get the current value of the atomic reference. *)
 
-(** Set a new value for the atomic reference. *)
 val set : 'a t -> 'a -> unit
+(** Set a new value for the atomic reference. *)
 
-(** Set a new value for the atomic reference, and return the current value. *)
 val exchange : 'a t -> 'a -> 'a
+(** Set a new value for the atomic reference, and return the current value. *)
 
+val compare_and_set : 'a t -> 'a -> 'a -> bool
 (** [compare_and_set r seen v] sets the new value of [r] to [v] only
     if its current value is physically equal to [seen] -- the
     comparison and the set occur atomically. Returns [true] if the
     comparison succeeded (so the set happened) and [false]
     otherwise. *)
-val compare_and_set : 'a t -> 'a -> 'a -> bool
 
+val fetch_and_add : int t -> int -> int
 (** [fetch_and_add r n] atomically increments the value of [r] by [n],
     and returns the current value (before the increment). *)
-val fetch_and_add : int t -> int -> int
 
-(** [incr r] atomically increments the value of [r] by [1]. *)
 val incr : int t -> unit
+(** [incr r] atomically increments the value of [r] by [1]. *)
 
-(** [decr r] atomically decrements the value of [r] by [1]. *)
 val decr : int t -> unit
+(** [decr r] atomically decrements the value of [r] by [1]. *)

src/atomic/dune

@@ -1,15 +1,15 @@
-
 (library
-  (name opentelemetry_atomic)
-  (synopsis "Compatibility package for the Atomic module for opentelemetry")
-  (public_name opentelemetry.atomic)
-  (modules atomic))
+ (name opentelemetry_atomic)
+ (synopsis "Compatibility package for the Atomic module for opentelemetry")
+ (public_name opentelemetry.atomic)
+ (modules atomic))
 
 (executable
-  (modules gen)
-  (name gen))
+ (modules gen)
+ (name gen))
 
 (rule
-  (targets atomic.ml atomic.mli atomic.ml)
-  (deps atomic.pre412.mli atomic.post412.mli)
-  (action (run ./gen.exe)))
+ (targets atomic.ml atomic.mli atomic.ml)
+ (deps atomic.pre412.mli atomic.post412.mli)
+ (action
+  (run ./gen.exe)))

src/atomic/gen.ml

@@ -1,6 +1,5 @@
-
-
-let atomic_before_412 = {|
+let atomic_before_412 =
+  {|
   type 'a t = {mutable x: 'a}
   let[@inline] make x = {x}
   let[@inline] get {x} = x
@@ -32,7 +31,9 @@ let atomic_before_412 = {|
 let atomic_after_412 = {|include Stdlib.Atomic|}
 
 let write_file file s =
-  let oc = open_out file in output_string oc s; close_out oc
+  let oc = open_out file in
+  output_string oc s;
+  close_out oc
 
 let copy_file file1 file2 =
   let oc = open_out file2 in
@@ -41,14 +42,22 @@ let copy_file file1 file2 =
   try
     while true do
       let n = input ic buf 0 (Bytes.length buf) in
-      if n=0 then raise End_of_file;
+      if n = 0 then raise End_of_file;
       output oc buf 0 n
     done
   with End_of_file -> ()
 
 let () =
-  let version = Scanf.sscanf Sys.ocaml_version "%d.%d.%s" (fun x y _ -> x,y) in
-  write_file "atomic.ml" (if version >= (4,12) then atomic_after_412 else atomic_before_412);
-  copy_file (if version >= (4,12) then "atomic.post412.mli" else "atomic.pre412.mli") "atomic.mli" ;
+  let version = Scanf.sscanf Sys.ocaml_version "%d.%d.%s" (fun x y _ -> x, y) in
+  write_file "atomic.ml"
+    (if version >= (4, 12) then
+      atomic_after_412
+    else
+      atomic_before_412);
+  copy_file
+    (if version >= (4, 12) then
+      "atomic.post412.mli"
+    else
+      "atomic.pre412.mli")
+    "atomic.mli";
   ()
-

src/client/AList.ml

@@ -1,13 +1,21 @@
 module Atomic = Opentelemetry_atomic.Atomic
 
 type 'a t = 'a list Atomic.t
+
 let make () = Atomic.make []
+
 let add self x =
   while
     let old = Atomic.get self in
     let l' = x :: old in
     not (Atomic.compare_and_set self old l')
-  do () done
+  do
+    ()
+  done
+
 let rec pop_all self =
   let l = Atomic.get self in
-  if Atomic.compare_and_set self l [] then l else pop_all self
+  if Atomic.compare_and_set self l [] then
+    l
+  else
+    pop_all self

src/client/AList.mli

@@ -1,6 +1,9 @@
 (** Atomic list *)
 
 type 'a t
+
 val make : unit -> 'a t
+
 val add : 'a t -> 'a -> unit
+
 val pop_all : 'a t -> 'a list

src/client/FQueue.ml

@@ -1,5 +1,3 @@
-
-
 type 'a t = {
   arr: 'a array;
   mutable i: int;
@@ -7,23 +5,23 @@ type 'a t = {
 
 let create ~dummy n : _ t =
   assert (n >= 1);
-  { arr=Array.make n dummy;
-    i=0;
-  }
+  { arr = Array.make n dummy; i = 0 }
 
 let[@inline] size self = self.i
+
 let[@inline] is_full self = self.i = Array.length self.arr
 
-let push (self:_ t) x : bool =
-  if is_full self then false
+let push (self : _ t) x : bool =
+  if is_full self then
+    false
   else (
     self.arr.(self.i) <- x;
     self.i <- 1 + self.i;
     true
   )
 
-let pop_iter_all (self: _ t) f =
-  for j=0 to self.i-1 do
+let pop_iter_all (self : _ t) f =
+  for j = 0 to self.i - 1 do
     f self.arr.(j)
   done;
   self.i <- 0

src/client/FQueue.mli

@@ -1,9 +1,11 @@
-
 (** queue of fixed size *)
 
 type 'a t
-val create : dummy:'a -> int -> 'a t
-val size : _ t -> int
-val push : 'a t -> 'a -> bool (* true iff it could write element *)
-val pop_iter_all : 'a t -> ('a -> unit) -> unit
 
+val create : dummy:'a -> int -> 'a t
+
+val size : _ t -> int
+
+val push : 'a t -> 'a -> bool (* true iff it could write element *)
+
+val pop_iter_all : 'a t -> ('a -> unit) -> unit

src/client/config.ml

@@ -1,4 +1,3 @@
-
 open Common_
 
 type t = {
@@ -14,28 +13,36 @@ type t = {
 
 let pp out self =
   let ppiopt = Format.pp_print_option Format.pp_print_int in
-  let pp_header ppf (a, b) =
-    Format.fprintf ppf "@[%s: @,%s@]@." a b ;
-  in
+  let pp_header ppf (a, b) = Format.fprintf ppf "@[%s: @,%s@]@." a b in
   let ppheaders = Format.pp_print_list pp_header in
-  let {debug; url; headers; batch_traces; batch_metrics;
-       batch_timeout_ms; thread; ticker_thread} = self in
+  let {
+    debug;
+    url;
+    headers;
+    batch_traces;
+    batch_metrics;
+    batch_timeout_ms;
+    thread;
+    ticker_thread;
+  } =
+    self
+  in
   Format.fprintf out
-    "{@[ debug=%B;@ url=%S;@ headers=%a;@ \
-     batch_traces=%a;@ batch_metrics=%a;@ \
+    "{@[ debug=%B;@ url=%S;@ headers=%a;@ batch_traces=%a;@ batch_metrics=%a;@ \
      batch_timeout_ms=%d; thread=%B;@ ticker_thread=%B @]}"
     debug url ppheaders headers ppiopt batch_traces ppiopt batch_metrics
     batch_timeout_ms thread ticker_thread
 
-let make
-    ?(debug= !debug_)
-    ?(url= get_url())
-    ?(headers= get_headers ())
-    ?(batch_traces=Some 400)
-    ?(batch_metrics=None)
-    ?(batch_timeout_ms=500)
-    ?(thread=true)
-    ?(ticker_thread=true)
-    () : t =
-  { debug; url; headers; batch_traces; batch_metrics; batch_timeout_ms;
-    thread; ticker_thread; }
+let make ?(debug = !debug_) ?(url = get_url ()) ?(headers = get_headers ())
+    ?(batch_traces = Some 400) ?(batch_metrics = None) ?(batch_timeout_ms = 500)
+    ?(thread = true) ?(ticker_thread = true) () : t =
+  {
+    debug;
+    url;
+    headers;
+    batch_traces;
+    batch_metrics;
+    batch_timeout_ms;
+    thread;
+    ticker_thread;
+  }

src/client/config.mli

@@ -1,56 +1,49 @@
-
 type t = {
   debug: bool;
-
   url: string;
-  (** Url of the endpoint. Default is "http://localhost:4318",
+      (** Url of the endpoint. Default is "http://localhost:4318",
       or "OTEL_EXPORTER_OTLP_ENDPOINT" if set. *)
-
   headers: (string * string) list;
-  (** API headers sent to the endpoint. Default is none or
+      (** API headers sent to the endpoint. Default is none or
       "OTEL_EXPORTER_OTLP_HEADERS" if set. *)
-
   batch_traces: int option;
-  (** Batch traces? If [Some i], then this produces batches of (at most)
+      (** Batch traces? If [Some i], then this produces batches of (at most)
       [i] items. If [None], there is no batching.
 
       Note that traces and metrics are batched separately.
       Default [Some 400].
   *)
-
   batch_metrics: int option;
-  (** Batch metrics? If [Some i], then this produces batches of (at most)
+      (** Batch metrics? If [Some i], then this produces batches of (at most)
       [i] items. If [None], there is no batching.
 
       Note that traces and metrics are batched separately.
       Default [None].
   *)
-
   batch_timeout_ms: int;
-  (** Number of milliseconds after which we will emit a batch, even
+      (** Number of milliseconds after which we will emit a batch, even
       incomplete.
       Note that the batch might take longer than that, because this is
       only checked when a new event occurs. Default 500. *)
-
-  thread: bool;
-  (** Is there a background thread? Default [true] *)
-
+  thread: bool;  (** Is there a background thread? Default [true] *)
   ticker_thread: bool;
-  (** Is there a ticker thread? Default [true].
+      (** Is there a ticker thread? Default [true].
       This thread will regularly call [tick()] on the backend, to make
       sure it makes progress, and regularly send events to the collector.
       This option is ignored if [thread=false]. *)
 }
 
 val make :
-  ?debug:bool -> ?url:string ->
+  ?debug:bool ->
+  ?url:string ->
   ?headers:(string * string) list ->
   ?batch_traces:int option ->
   ?batch_metrics:int option ->
   ?batch_timeout_ms:int ->
   ?thread:bool ->
   ?ticker_thread:bool ->
-  unit -> t
+  unit ->
+  t
 (** Make a configuration *)
 
 val pp : Format.formatter -> t -> unit

src/client/dune

@@ -1,8 +1,5 @@
-
 (library
-  (name opentelemetry_client_ocurl)
-  (public_name opentelemetry-client-ocurl)
-  (libraries opentelemetry opentelemetry.atomic
-             curl pbrt threads
-             mtime mtime.clock.os))
-
+ (name opentelemetry_client_ocurl)
+ (public_name opentelemetry-client-ocurl)
+ (libraries opentelemetry opentelemetry.atomic curl pbrt threads mtime
+   mtime.clock.os))

src/client/opentelemetry_client_ocurl.mli

@@ -1,4 +1,3 @@
-
 (*
    TODO: more options from
    https://opentelemetry.io/docs/reference/specification/protocol/exporter/

src/dune

@@ -8,88 +8,91 @@
 ; ### protobuf rules ###
 
 (rule
-  (alias lint)
-  (mode promote)
-  (targets status_types.ml status_types.mli
-           status_pb.ml status_pb.mli
-           status_pp.ml status_pp.mli)
-  (deps (:file status.proto)
-        (source_tree %{project_root}/vendor/opentelemetry-proto/))
-  (action (run ocaml-protoc %{file} -ml_out . -pp -binary)))
+ (alias lint)
+ (mode promote)
+ (targets status_types.ml status_types.mli status_pb.ml status_pb.mli
+   status_pp.ml status_pp.mli)
+ (deps
+  (:file status.proto)
+  (source_tree %{project_root}/vendor/opentelemetry-proto/))
+ (action
+  (run ocaml-protoc %{file} -ml_out . -pp -binary)))
 
 (rule
-  (alias lint)
-  (mode promote)
-  (targets common_types.ml common_types.mli
-           common_pb.ml common_pb.mli
-           common_pp.ml common_pp.mli)
-  (deps
-    (:file %{project_root}/vendor/opentelemetry-proto/opentelemetry/proto/common/v1/common.proto)
-    (source_tree %{project_root}/vendor/opentelemetry-proto/))
-  (action (run ocaml-protoc %{file}
-               -I %{project_root}/vendor/opentelemetry-proto/
-               -ml_out . -pp -binary)))
+ (alias lint)
+ (mode promote)
+ (targets common_types.ml common_types.mli common_pb.ml common_pb.mli
+   common_pp.ml common_pp.mli)
+ (deps
+  (:file
+    %{project_root}/vendor/opentelemetry-proto/opentelemetry/proto/common/v1/common.proto)
+  (source_tree %{project_root}/vendor/opentelemetry-proto/))
+ (action
+  (run ocaml-protoc %{file} -I %{project_root}/vendor/opentelemetry-proto/
+    -ml_out . -pp -binary)))
 
 (rule
-  (alias lint)
-  (mode promote)
-  (targets resource_types.ml resource_types.mli
-           resource_pb.ml resource_pb.mli
-           resource_pp.ml resource_pp.mli)
-  (deps
-    (:file %{project_root}/vendor/opentelemetry-proto/opentelemetry/proto/resource/v1/resource.proto)
-    (source_tree %{project_root}/vendor/opentelemetry-proto/))
-  (action (run ocaml-protoc %{file}
-               -I %{project_root}/vendor/opentelemetry-proto/
-               -ml_out . -pp -binary)))
+ (alias lint)
+ (mode promote)
+ (targets resource_types.ml resource_types.mli resource_pb.ml resource_pb.mli
+   resource_pp.ml resource_pp.mli)
+ (deps
+  (:file
+    %{project_root}/vendor/opentelemetry-proto/opentelemetry/proto/resource/v1/resource.proto)
+  (source_tree %{project_root}/vendor/opentelemetry-proto/))
+ (action
+  (run ocaml-protoc %{file} -I %{project_root}/vendor/opentelemetry-proto/
+    -ml_out . -pp -binary)))
 
 (rule
-  (alias lint)
-  (mode promote)
-  (targets trace_types.ml trace_types.mli
-           trace_pb.ml trace_pb.mli
-           trace_pp.ml trace_pp.mli)
-  (deps
-    (:file %{project_root}/vendor/opentelemetry-proto/opentelemetry/proto/trace/v1/trace.proto)
-    (source_tree %{project_root}/vendor/opentelemetry-proto/))
-  (action (run ocaml-protoc %{file}
-               -I %{project_root}/vendor/opentelemetry-proto/
-               -ml_out . -pp -binary)))
+ (alias lint)
+ (mode promote)
+ (targets trace_types.ml trace_types.mli trace_pb.ml trace_pb.mli trace_pp.ml
+   trace_pp.mli)
+ (deps
+  (:file
+    %{project_root}/vendor/opentelemetry-proto/opentelemetry/proto/trace/v1/trace.proto)
+  (source_tree %{project_root}/vendor/opentelemetry-proto/))
+ (action
+  (run ocaml-protoc %{file} -I %{project_root}/vendor/opentelemetry-proto/
+    -ml_out . -pp -binary)))
 
 (rule
-  (alias lint)
-  (mode promote)
-  (targets metrics_types.ml metrics_types.mli
-           metrics_pb.ml metrics_pb.mli
-           metrics_pp.ml metrics_pp.mli)
-  (deps
-    (:file %{project_root}/vendor/opentelemetry-proto/opentelemetry/proto/metrics/v1/metrics.proto)
-    (source_tree %{project_root}/vendor/opentelemetry-proto/))
-  (action (run ocaml-protoc %{file}
-               -I %{project_root}/vendor/opentelemetry-proto/
-               -ml_out . -pp -binary)))
+ (alias lint)
+ (mode promote)
+ (targets metrics_types.ml metrics_types.mli metrics_pb.ml metrics_pb.mli
+   metrics_pp.ml metrics_pp.mli)
+ (deps
+  (:file
+    %{project_root}/vendor/opentelemetry-proto/opentelemetry/proto/metrics/v1/metrics.proto)
+  (source_tree %{project_root}/vendor/opentelemetry-proto/))
+ (action
+  (run ocaml-protoc %{file} -I %{project_root}/vendor/opentelemetry-proto/
+    -ml_out . -pp -binary)))
 
 (rule
-  (alias lint)
-  (mode promote)
-  (targets metrics_service_types.ml metrics_service_types.mli
-           metrics_service_pp.ml metrics_service_pp.mli
-           metrics_service_pb.ml metrics_service_pb.mli)
-  (deps (:file %{project_root}/vendor/opentelemetry-proto/opentelemetry/proto/collector/metrics/v1/metrics_service.proto)
-    (source_tree %{project_root}/vendor/opentelemetry-proto/))
-  (action (run ocaml-protoc %{file}
-               -I %{project_root}/vendor/opentelemetry-proto/
-               -ml_out . -pp -binary)))
+ (alias lint)
+ (mode promote)
+ (targets metrics_service_types.ml metrics_service_types.mli
+   metrics_service_pp.ml metrics_service_pp.mli metrics_service_pb.ml
+   metrics_service_pb.mli)
+ (deps
+  (:file
+    %{project_root}/vendor/opentelemetry-proto/opentelemetry/proto/collector/metrics/v1/metrics_service.proto)
+  (source_tree %{project_root}/vendor/opentelemetry-proto/))
+ (action
+  (run ocaml-protoc %{file} -I %{project_root}/vendor/opentelemetry-proto/
+    -ml_out . -pp -binary)))
 
 (rule
-  (alias lint)
-  (mode promote)
-  (targets trace_service_types.ml trace_service_types.mli
-           trace_service_pp.ml trace_service_pp.mli
-           trace_service_pb.ml trace_service_pb.mli)
-  (deps
-    (:file %{project_root}/vendor/opentelemetry-proto/opentelemetry/proto/collector/trace/v1/trace_service.proto)
-    (source_tree %{project_root}/vendor/opentelemetry-proto/))
-  (action (run ocaml-protoc %{file}
-               -I %{project_root}/vendor/opentelemetry-proto/
-               -ml_out . -pp -binary)))
+ (alias lint)
+ (mode promote)
+ (targets trace_service_types.ml trace_service_types.mli trace_service_pp.ml
+   trace_service_pp.mli trace_service_pb.ml trace_service_pb.mli)
+ (deps
+  (:file
+    %{project_root}/vendor/opentelemetry-proto/opentelemetry/proto/collector/trace/v1/trace_service.proto)
+  (source_tree %{project_root}/vendor/opentelemetry-proto/))
+ (action
+  (run ocaml-protoc %{file} -I %{project_root}/vendor/opentelemetry-proto/
+    -ml_out . -pp -binary)))

src/integrations/cohttp/opentelemetry_cohttp_lwt.ml

@@ -4,6 +4,14 @@ open Cohttp
 open Cohttp_lwt
 
 module Server : sig
+  val trace :
+    ?service_name:string ->
+    ?attrs:Otel.Span.key_value list ->
+    ('conn -> Request.t -> 'body -> (Response.t * 'body) Lwt.t) ->
+    'conn ->
+    Request.t ->
+    'body ->
+    (Response.t * 'body) Lwt.t
   (** Trace requests to a Cohttp server.
 
       Use it like this:
@@ -18,19 +26,8 @@ module Server : sig
               ~mode:(`TCP (`Port 8080))
               (Server.make () ~callback:callback_traced)
    *)
-  val trace :
-    ?service_name:string ->
-    ?attrs:Otel.Span.key_value list ->
-    ('conn -> Request.t -> 'body -> (Response.t * 'body) Lwt.t) ->
-    'conn -> Request.t -> 'body -> (Response.t * 'body) Lwt.t
 
-  (** Trace a new internal span.
-
-      Identical to [Opentelemetry_lwt.Trace.with_], but fetches/stores the trace
-      scope in the [x-ocaml-otel-traceparent] header in the request for
-      convenience.
-   *)
-  val with_:
+  val with_ :
     ?trace_state:string ->
     ?service_name:string ->
     ?attrs:Otel.Span.key_value list ->
@@ -40,21 +37,28 @@ module Server : sig
     Request.t ->
     (Request.t -> 'a Lwt.t) ->
     'a Lwt.t
+  (** Trace a new internal span.
 
+      Identical to [Opentelemetry_lwt.Trace.with_], but fetches/stores the trace
+      scope in the [x-ocaml-otel-traceparent] header in the request for
+      convenience.
+   *)
+
+  val get_trace_context :
+    ?from:[ `Internal | `External ] -> Request.t -> Otel.Trace.scope option
   (** Get the tracing scope from the custom [x-ocaml-otel-traceparent] header
       added by [trace] and [with_].
    *)
-  val get_trace_context : ?from:[`Internal | `External] -> Request.t -> Otel.Trace.scope option
 
+  val set_trace_context : Otel.Trace.scope -> Request.t -> Request.t
   (** Set the tracing scope in the custom [x-ocaml-otel-traceparent] header used
       by [trace] and [with_].
    *)
-  val set_trace_context : Otel.Trace.scope -> Request.t -> Request.t
 
+  val remove_trace_context : Request.t -> Request.t
   (** Strip the custom [x-ocaml-otel-traceparent] header added by [trace] and
       [with_].
    *)
-  val remove_trace_context : Request.t -> Request.t
 end = struct
   let attrs_of_request (req : Request.t) =
     let meth = req |> Request.meth |> Code.string_of_method in
@@ -63,25 +67,24 @@ end = struct
     let ua = Header.get (Request.headers req) "user-agent" in
     let uri = Request.uri req in
     List.concat
-      [ [ ("http.method", `String meth) ]
-      ; (match host with None -> [] | Some h -> [ ("http.host", `String h) ])
-      ; [ ("http.url", `String (Uri.to_string uri)) ]
-      ; ( match ua with
-          | None ->
-             []
-          | Some ua ->
-             [ ("http.user_agent", `String ua) ] )
-      ; ( match referer with
-          | None ->
-             []
-          | Some r ->
-             [ ("http.request.header.referer", `String r) ] )
+      [
+        [ "http.method", `String meth ];
+        (match host with
+        | None -> []
+        | Some h -> [ "http.host", `String h ]);
+        [ "http.url", `String (Uri.to_string uri) ];
+        (match ua with
+        | None -> []
+        | Some ua -> [ "http.user_agent", `String ua ]);
+        (match referer with
+        | None -> []
+        | Some r -> [ "http.request.header.referer", `String r ]);
       ]
 
   let attrs_of_response (res : Response.t) =
     let code = Response.status res in
     let code = Code.code_of_status code in
-    [ ("http.status_code", `Int code) ]
+    [ "http.status_code", `Int code ]
 
   let header_x_ocaml_otel_traceparent = "x-ocaml-otel-traceparent"
 
@@ -89,11 +92,12 @@ end = struct
     let module Traceparent = Otel.Trace_context.Traceparent in
     let headers =
       Header.add (Request.headers req) header_x_ocaml_otel_traceparent
-        (Traceparent.to_value ~trace_id:scope.trace_id ~parent_id:scope.span_id ())
+        (Traceparent.to_value ~trace_id:scope.trace_id ~parent_id:scope.span_id
+           ())
     in
     { req with headers }
 
-  let get_trace_context ?(from=`Internal) req =
+  let get_trace_context ?(from = `Internal) req =
     let module Traceparent = Otel.Trace_context.Traceparent in
     let name =
       match from with
@@ -103,125 +107,125 @@ end = struct
     match Header.get (Request.headers req) name with
     | None -> None
     | Some v ->
-       (match Traceparent.of_value v with
-        | Ok (trace_id, parent_id) ->
-           (Some Otel.Trace.{ trace_id; span_id = parent_id; events = []; attrs = []})
-        | Error _ -> None)
+      (match Traceparent.of_value v with
+      | Ok (trace_id, parent_id) ->
+        Some
+          Otel.Trace.{ trace_id; span_id = parent_id; events = []; attrs = [] }
+      | Error _ -> None)
 
   let remove_trace_context req =
-    let headers = Header.remove (Request.headers req) header_x_ocaml_otel_traceparent in
+    let headers =
+      Header.remove (Request.headers req) header_x_ocaml_otel_traceparent
+    in
     { req with headers }
 
-  let trace ?service_name ?(attrs=[]) callback =
-    fun conn req body ->
+  let trace ?service_name ?(attrs = []) callback conn req body =
     let scope = get_trace_context ~from:`External req in
-    Otel_lwt.Trace.with_
-      ?service_name
-      "request"
-      ~kind:Span_kind_server
+    Otel_lwt.Trace.with_ ?service_name "request" ~kind:Span_kind_server
       ?trace_id:(Option.map (fun scope -> scope.Otel.Trace.trace_id) scope)
       ?parent:(Option.map (fun scope -> scope.Otel.Trace.span_id) scope)
       ~attrs:(attrs @ attrs_of_request req)
       (fun scope ->
         let open Lwt.Syntax in
         let req = set_trace_context scope req in
-        let* (res, body) = callback conn req body in
-        Otel.Trace.add_attrs scope (fun () -> attrs_of_response res) ;
-        Lwt.return (res, body) )
+        let* res, body = callback conn req body in
+        Otel.Trace.add_attrs scope (fun () -> attrs_of_response res);
+        Lwt.return (res, body))
 
-  let with_ ?trace_state ?service_name ?attrs ?(kind=Otel.Span.Span_kind_internal) ?links name req (f : Request.t -> 'a Lwt.t) =
+  let with_ ?trace_state ?service_name ?attrs
+      ?(kind = Otel.Span.Span_kind_internal) ?links name req
+      (f : Request.t -> 'a Lwt.t) =
     let scope = get_trace_context ~from:`Internal req in
-    Otel_lwt.Trace.with_
-      ?trace_state
-      ?service_name
-      ?attrs
-      ~kind
+    Otel_lwt.Trace.with_ ?trace_state ?service_name ?attrs ~kind
       ?trace_id:(Option.map (fun scope -> scope.Otel.Trace.trace_id) scope)
       ?parent:(Option.map (fun scope -> scope.Otel.Trace.span_id) scope)
-      ?links
-      name
+      ?links name
       (fun scope ->
         let open Lwt.Syntax in
         let req = set_trace_context scope req in
         f req)
 end
 
-let client ?(scope : Otel.Trace.scope option) (module C : Cohttp_lwt.S.Client)  =
+let client ?(scope : Otel.Trace.scope option) (module C : Cohttp_lwt.S.Client) =
   let module Traced = struct
-      open Lwt.Syntax
+    open Lwt.Syntax
 
-      let attrs_for ~uri ~meth () =
-        [ ("http.method", `String (Code.string_of_method `GET))
-        ; ("http.url", `String (Uri.to_string uri))
-        ]
+    let attrs_for ~uri ~meth () =
+      [
+        "http.method", `String (Code.string_of_method `GET);
+        "http.url", `String (Uri.to_string uri);
+      ]
 
-      let context_for ~uri ~meth =
-        let trace_id = match scope with | Some scope -> Some scope.trace_id | None -> None in
-        let parent = match scope with | Some scope -> Some scope.span_id | None -> None in
-        let attrs = attrs_for ~uri ~meth () in
-        (trace_id, parent, attrs)
+    let context_for ~uri ~meth =
+      let trace_id =
+        match scope with
+        | Some scope -> Some scope.trace_id
+        | None -> None
+      in
+      let parent =
+        match scope with
+        | Some scope -> Some scope.span_id
+        | None -> None
+      in
+      let attrs = attrs_for ~uri ~meth () in
+      trace_id, parent, attrs
 
-      let add_traceparent (scope : Otel.Trace.scope) headers =
-        let module Traceparent = Otel.Trace_context.Traceparent in
-        let headers = match headers with | None -> Header.init () | Some headers -> headers in
-        Header.add headers Traceparent.name
-          (Traceparent.to_value ~trace_id:scope.trace_id ~parent_id:scope.span_id ())
+    let add_traceparent (scope : Otel.Trace.scope) headers =
+      let module Traceparent = Otel.Trace_context.Traceparent in
+      let headers =
+        match headers with
+        | None -> Header.init ()
+        | Some headers -> headers
+      in
+      Header.add headers Traceparent.name
+        (Traceparent.to_value ~trace_id:scope.trace_id ~parent_id:scope.span_id
+           ())
 
-      type ctx = C.ctx
+    type ctx = C.ctx
 
-      let call ?ctx ?headers ?body ?chunked meth (uri : Uri.t) : (Response.t * Cohttp_lwt.Body.t) Lwt.t =
-        let (trace_id, parent, attrs) = context_for ~uri ~meth in
-        Otel_lwt.Trace.with_ "request"
-          ~kind:Span_kind_client
-          ?trace_id
-          ?parent
-          ~attrs
-          (fun scope ->
-            let headers = add_traceparent scope headers in
-            let* (res, body) = C.call ?ctx ~headers ?body ?chunked meth uri in
-            Otel.Trace.add_attrs scope (fun () ->
-                let code = Response.status res in
-                let code = Code.code_of_status code in
-                [ ("http.status_code", `Int code) ]) ;
-            Lwt.return (res, body))
+    let call ?ctx ?headers ?body ?chunked meth (uri : Uri.t) :
+        (Response.t * Cohttp_lwt.Body.t) Lwt.t =
+      let trace_id, parent, attrs = context_for ~uri ~meth in
+      Otel_lwt.Trace.with_ "request" ~kind:Span_kind_client ?trace_id ?parent
+        ~attrs (fun scope ->
+          let headers = add_traceparent scope headers in
+          let* res, body = C.call ?ctx ~headers ?body ?chunked meth uri in
+          Otel.Trace.add_attrs scope (fun () ->
+              let code = Response.status res in
+              let code = Code.code_of_status code in
+              [ "http.status_code", `Int code ]);
+          Lwt.return (res, body))
 
-      let head ?ctx ?headers uri =
-        let open Lwt.Infix in
-        call ?ctx ?headers `HEAD uri >|= fst
+    let head ?ctx ?headers uri =
+      let open Lwt.Infix in
+      call ?ctx ?headers `HEAD uri >|= fst
 
-      let get ?ctx ?headers uri = call ?ctx ?headers `GET uri
+    let get ?ctx ?headers uri = call ?ctx ?headers `GET uri
 
-      let delete ?ctx ?body ?chunked ?headers uri =
-        call ?ctx ?headers ?body ?chunked `DELETE uri
+    let delete ?ctx ?body ?chunked ?headers uri =
+      call ?ctx ?headers ?body ?chunked `DELETE uri
 
-      let post ?ctx ?body ?chunked ?headers uri =
-        call ?ctx ?headers ?body ?chunked `POST uri
+    let post ?ctx ?body ?chunked ?headers uri =
+      call ?ctx ?headers ?body ?chunked `POST uri
 
-      let put ?ctx ?body ?chunked ?headers uri =
-        call ?ctx ?headers ?body ?chunked `PUT uri
+    let put ?ctx ?body ?chunked ?headers uri =
+      call ?ctx ?headers ?body ?chunked `PUT uri
 
-      let patch ?ctx ?body ?chunked ?headers uri =
-        call ?ctx ?headers ?body ?chunked `PATCH uri
+    let patch ?ctx ?body ?chunked ?headers uri =
+      call ?ctx ?headers ?body ?chunked `PATCH uri
 
-      let post_form ?ctx ?headers ~params uri =
-        let (trace_id, parent, attrs) = context_for ~uri ~meth:`POST in
-        Otel_lwt.Trace.with_ "request"
-          ~kind:Span_kind_client
-          ?trace_id
-          ?parent
-          ~attrs
-          (fun scope ->
-            let headers = add_traceparent scope headers in
-            let* (res, body) =
-              C.post_form ?ctx ~headers ~params uri
-            in
-            Otel.Trace.add_attrs scope (fun () ->
-                let code = Response.status res in
-                let code = Code.code_of_status code in
-                [ ("http.status_code", `Int code) ]) ;
-            Lwt.return (res, body))
+    let post_form ?ctx ?headers ~params uri =
+      let trace_id, parent, attrs = context_for ~uri ~meth:`POST in
+      Otel_lwt.Trace.with_ "request" ~kind:Span_kind_client ?trace_id ?parent
+        ~attrs (fun scope ->
+          let headers = add_traceparent scope headers in
+          let* res, body = C.post_form ?ctx ~headers ~params uri in
+          Otel.Trace.add_attrs scope (fun () ->
+              let code = Response.status res in
+              let code = Code.code_of_status code in
+              [ "http.status_code", `Int code ]);
+          Lwt.return (res, body))
 
-      let callv = C.callv (* TODO *)
-    end
-  in
+    let callv = C.callv (* TODO *)
+  end in
   (module Traced : Cohttp_lwt.S.Client)

src/lwt/dune

@@ -1,5 +1,5 @@
 (library
-  (name opentelemetry_lwt)
-  (public_name opentelemetry-lwt)
-  (synopsis "Lwt frontend for opentelemetry")
-  (libraries lwt opentelemetry))
+ (name opentelemetry_lwt)
+ (public_name opentelemetry-lwt)
+ (synopsis "Lwt frontend for opentelemetry")
+ (libraries lwt opentelemetry))

src/lwt/opentelemetry_lwt.ml

@@ -1,6 +1,5 @@
 open Opentelemetry
 open Lwt.Syntax
-
 module Span_id = Span_id
 module Trace_id = Trace_id
 module Event = Event
@@ -15,10 +14,8 @@ module Trace = struct
   include Trace
 
   (** Sync span guard *)
-  let with_
-      ?trace_state ?service_name ?(attrs=[])
-      ?kind ?trace_id ?parent ?scope ?links
-      name (f:Trace.scope -> 'a Lwt.t) : 'a Lwt.t =
+  let with_ ?trace_state ?service_name ?(attrs = []) ?kind ?trace_id ?parent
+      ?scope ?links name (f : Trace.scope -> 'a Lwt.t) : 'a Lwt.t =
     let trace_id =
       match trace_id, scope with
       | Some trace_id, _ -> trace_id
@@ -31,30 +28,31 @@ module Trace = struct
       | None, Some scope -> Some scope.span_id
       | None, None -> None
     in
-    let start_time = Timestamp_ns.now_unix_ns() in
-    let span_id = Span_id.create() in
-    let scope = {trace_id;span_id;events=[];attrs} in
+    let start_time = Timestamp_ns.now_unix_ns () in
+    let span_id = Span_id.create () in
+    let scope = { trace_id; span_id; events = []; attrs } in
     let finally ok =
-      let status = match ok with
+      let status =
+        match ok with
         | Ok () -> default_status ~code:Status_code_ok ()
-        | Error e -> default_status ~code:Status_code_error ~message:e () in
+        | Error e -> default_status ~code:Status_code_error ~message:e ()
+      in
       let span, _ =
-        Span.create
-          ?kind ~trace_id ?parent ?links ~id:span_id
-          ?trace_state ~attrs:scope.attrs ~events:scope.events
-          ~start_time ~end_time:(Timestamp_ns.now_unix_ns())
-          ~status
-          name in
-      emit ?service_name [span]
+        Span.create ?kind ~trace_id ?parent ?links ~id:span_id ?trace_state
+          ~attrs:scope.attrs ~events:scope.events ~start_time
+          ~end_time:(Timestamp_ns.now_unix_ns ())
+          ~status name
+      in
+      emit ?service_name [ span ]
     in
     Lwt.catch
       (fun () ->
-         let* x = f scope in
-         let () = finally (Ok ()) in
-         Lwt.return x)
+        let* x = f scope in
+        let () = finally (Ok ()) in
+        Lwt.return x)
       (fun e ->
-         let () = finally (Error (Printexc.to_string e)) in
-         Lwt.fail e)
+        let () = finally (Error (Printexc.to_string e)) in
+        Lwt.fail e)
 end
 
 module Metrics = struct

tests/bin/cohttp_client.ml

@@ -1,25 +1,29 @@
 module T = Opentelemetry
 module Otel_lwt = Opentelemetry_lwt
+
 let spf = Printf.sprintf
-let (let@) f x = f x
+
+let ( let@ ) f x = f x
 
 let sleep_inner = ref 0.1
+
 let sleep_outer = ref 2.0
 
-let mk_client ~scope = Opentelemetry_cohttp_lwt.client ~scope (module Cohttp_lwt_unix.Client)
+let mk_client ~scope =
+  Opentelemetry_cohttp_lwt.client ~scope (module Cohttp_lwt_unix.Client)
 
 let run () =
-  Printf.printf "collector is on %S\n%!" (Opentelemetry_client_ocurl.get_url());
+  Printf.printf "collector is on %S\n%!" (Opentelemetry_client_ocurl.get_url ());
   let open Lwt.Syntax in
   let rec go () =
     let@ scope =
-      Otel_lwt.Trace.with_
-        ~kind:T.Span.Span_kind_producer
-        "loop.outer"
+      Otel_lwt.Trace.with_ ~kind:T.Span.Span_kind_producer "loop.outer"
     in
     let* () = Lwt_unix.sleep !sleep_outer in
     let module C = (val mk_client ~scope) in
-    let* (res, body) = C.get (Uri.of_string "https://enec1hql02hz.x.pipedream.net") in
+    let* res, body =
+      C.get (Uri.of_string "https://enec1hql02hz.x.pipedream.net")
+    in
     let* () = Cohttp_lwt.Body.drain_body body in
     go ()
   in
@@ -34,26 +38,40 @@ let () =
   let thread = ref true in
   let batch_traces = ref 400 in
   let batch_metrics = ref 3 in
-  let opts = [
-      "--debug", Arg.Bool ((:=) debug), " enable debug output";
-      "--thread", Arg.Bool ((:=) thread), " use a background thread";
-      "--batch-traces", Arg.Int ((:=) batch_traces), " size of traces batch";
-      "--batch-metrics", Arg.Int ((:=) batch_metrics), " size of metrics batch";
+  let opts =
+    [
+      "--debug", Arg.Bool (( := ) debug), " enable debug output";
+      "--thread", Arg.Bool (( := ) thread), " use a background thread";
+      "--batch-traces", Arg.Int (( := ) batch_traces), " size of traces batch";
+      ( "--batch-metrics",
+        Arg.Int (( := ) batch_metrics),
+        " size of metrics batch" );
       "--sleep-inner", Arg.Set_float sleep_inner, " sleep (in s) in inner loop";
       "--sleep-outer", Arg.Set_float sleep_outer, " sleep (in s) in outer loop";
-    ] |> Arg.align in
+    ]
+    |> Arg.align
+  in
 
   Arg.parse opts (fun _ -> ()) "emit1 [opt]*";
 
-  let some_if_nzero r = if !r > 0 then Some !r else None in
-  let config = Opentelemetry_client_ocurl.Config.make
-                 ~debug:!debug
-                 ~batch_traces:(some_if_nzero batch_traces)
-                 ~batch_metrics:(some_if_nzero batch_metrics)
-                 ~thread:!thread () in
+  let some_if_nzero r =
+    if !r > 0 then
+      Some !r
+    else
+      None
+  in
+  let config =
+    Opentelemetry_client_ocurl.Config.make ~debug:!debug
+      ~batch_traces:(some_if_nzero batch_traces)
+      ~batch_metrics:(some_if_nzero batch_metrics)
+      ~thread:!thread ()
+  in
   Format.printf "@[<2>sleep outer: %.3fs,@ sleep inner: %.3fs,@ config: %a@]@."
     !sleep_outer !sleep_inner Opentelemetry_client_ocurl.Config.pp config;
 
-  Format.printf "Check HTTP requests at https://requestbin.com/r/enec1hql02hz/26qShWryt5vJc1JfrOwalhr5vQt@.";
+  Format.printf
+    "Check HTTP requests at \
+     https://requestbin.com/r/enec1hql02hz/26qShWryt5vJc1JfrOwalhr5vQt@.";
 
-  Opentelemetry_client_ocurl.with_setup ~config () (fun () -> Lwt_main.run (run ()))
+  Opentelemetry_client_ocurl.with_setup ~config () (fun () ->
+      Lwt_main.run (run ()))

tests/bin/dune

@@ -6,4 +6,5 @@
 (executable
  (name cohttp_client)
  (modules cohttp_client)
- (libraries cohttp-lwt-unix opentelemetry opentelemetry-client-ocurl opentelemetry-cohttp-lwt))
+ (libraries cohttp-lwt-unix opentelemetry opentelemetry-client-ocurl
+   opentelemetry-cohttp-lwt))

tests/bin/emit1.ml

@@ -1,41 +1,43 @@
-
 module T = Opentelemetry
+
 let spf = Printf.sprintf
-let (let@) f x = f x
+
+let ( let@ ) f x = f x
 
 let sleep_inner = ref 0.1
+
 let sleep_outer = ref 2.0
+
 let num_sleep = ref 0
 
 let run () =
-  Printf.printf "collector is on %S\n%!" (Opentelemetry_client_ocurl.get_url());
-  T.GC_metrics.basic_setup();
+  Printf.printf "collector is on %S\n%!" (Opentelemetry_client_ocurl.get_url ());
+  T.GC_metrics.basic_setup ();
 
   T.Metrics_callbacks.register (fun () ->
-    T.Metrics.[ sum ~name:"num-sleep" ~is_monotonic:true [int !num_sleep] ]);
+      T.Metrics.[ sum ~name:"num-sleep" ~is_monotonic:true [ int !num_sleep ] ]);
 
   let i = ref 0 in
   while true do
     let@ scope =
-      T.Trace.with_
-        ~kind:T.Span.Span_kind_producer
-        "loop.outer" ~attrs:["i", `Int !i] in
+      T.Trace.with_ ~kind:T.Span.Span_kind_producer "loop.outer"
+        ~attrs:[ "i", `Int !i ]
+    in
 
-    for j=0 to 4 do
-
-      let@ scope = T.Trace.with_ ~kind:T.Span.Span_kind_internal ~scope
-          ~attrs:["j", `Int j]
-          "loop.inner" in
+    for j = 0 to 4 do
+      let@ scope =
+        T.Trace.with_ ~kind:T.Span.Span_kind_internal ~scope
+          ~attrs:[ "j", `Int j ]
+          "loop.inner"
+      in
 
       Unix.sleepf !sleep_outer;
       incr num_sleep;
 
       incr i;
 
-      (try
-        let@ _ =
-          T.Trace.with_ ~kind:T.Span.Span_kind_internal ~scope
-            "alloc" in
+      try
+        let@ _ = T.Trace.with_ ~kind:T.Span.Span_kind_internal ~scope "alloc" in
         (* allocate some stuff *)
         let _arr = Sys.opaque_identity @@ Array.make (25 * 25551) 42.0 in
         ignore _arr;
@@ -43,12 +45,12 @@ let run () =
         Unix.sleepf !sleep_inner;
         incr num_sleep;
 
-        if j=4 && !i mod 13 = 0 then failwith "oh no"; (* simulate a failure *)
+        if j = 4 && !i mod 13 = 0 then failwith "oh no";
 
-        T.Trace.add_event scope (fun()->T.Event.make "done with alloc");
-      with Failure _ ->
-        ());
-    done;
+        (* simulate a failure *)
+        T.Trace.add_event scope (fun () -> T.Event.make "done with alloc")
+      with Failure _ -> ()
+    done
   done
 
 let () =
@@ -60,23 +62,34 @@ let () =
   let thread = ref true in
   let batch_traces = ref 400 in
   let batch_metrics = ref 3 in
-  let opts = [
-    "--debug", Arg.Bool ((:=) debug), " enable debug output";
-    "--thread", Arg.Bool ((:=) thread), " use a background thread";
-    "--batch-traces", Arg.Int ((:=) batch_traces), " size of traces batch";
-    "--batch-metrics", Arg.Int ((:=) batch_metrics), " size of metrics batch";
-    "--sleep-inner", Arg.Set_float sleep_inner, " sleep (in s) in inner loop";
-    "--sleep-outer", Arg.Set_float sleep_outer, " sleep (in s) in outer loop";
-  ] |> Arg.align in
+  let opts =
+    [
+      "--debug", Arg.Bool (( := ) debug), " enable debug output";
+      "--thread", Arg.Bool (( := ) thread), " use a background thread";
+      "--batch-traces", Arg.Int (( := ) batch_traces), " size of traces batch";
+      ( "--batch-metrics",
+        Arg.Int (( := ) batch_metrics),
+        " size of metrics batch" );
+      "--sleep-inner", Arg.Set_float sleep_inner, " sleep (in s) in inner loop";
+      "--sleep-outer", Arg.Set_float sleep_outer, " sleep (in s) in outer loop";
+    ]
+    |> Arg.align
+  in
 
   Arg.parse opts (fun _ -> ()) "emit1 [opt]*";
 
-  let some_if_nzero r = if !r > 0 then Some !r else None in
-  let config = Opentelemetry_client_ocurl.Config.make
-      ~debug:!debug
+  let some_if_nzero r =
+    if !r > 0 then
+      Some !r
+    else
+      None
+  in
+  let config =
+    Opentelemetry_client_ocurl.Config.make ~debug:!debug
       ~batch_traces:(some_if_nzero batch_traces)
       ~batch_metrics:(some_if_nzero batch_metrics)
-      ~thread:!thread () in
+      ~thread:!thread ()
+  in
   Format.printf "@[<2>sleep outer: %.3fs,@ sleep inner: %.3fs,@ config: %a@]@."
     !sleep_outer !sleep_inner Opentelemetry_client_ocurl.Config.pp config;
 

tests/test_trace_context.ml

@@ -2,39 +2,49 @@ open Opentelemetry
 
 let pp_traceparent fmt (trace_id, parent_id) =
   let open Format in
-  fprintf fmt "trace_id:%S parent_id:%S"
-    (Trace_id.to_hex trace_id)
+  fprintf fmt "trace_id:%S parent_id:%S" (Trace_id.to_hex trace_id)
     (Span_id.to_hex parent_id)
 
-
 let test_of_value str =
   let open Format in
-  printf "@[<v 2>Trace_context.Traceparent.of_value %S:@ %a@]@."
-    str
-    (pp_print_result ~ok:(fun fmt (trace_id, parent_id) ->
+  printf "@[<v 2>Trace_context.Traceparent.of_value %S:@ %a@]@." str
+    (pp_print_result
+       ~ok:(fun fmt (trace_id, parent_id) ->
          fprintf fmt "Ok %a" pp_traceparent (trace_id, parent_id))
        ~error:(fun fmt msg -> fprintf fmt "Error %S" msg))
     (Trace_context.Traceparent.of_value str)
 
 let () = test_of_value "xx"
+
 let () = test_of_value "00"
+
 let () = test_of_value "00-xxxx"
+
 let () = test_of_value "00-xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx"
+
 let () = test_of_value "00-0123456789abcdef0123456789abcdef"
+
 let () = test_of_value "00-0123456789abcdef0123456789abcdef-xxxx"
+
 let () = test_of_value "00-0123456789abcdef0123456789abcdef-xxxxxxxxxxxxxxxx"
+
 let () = test_of_value "00-0123456789abcdef0123456789abcdef-0123456789abcdef"
+
 let () = test_of_value "00-0123456789abcdef0123456789abcdef-0123456789abcdef-"
+
 let () = test_of_value "00-0123456789abcdef0123456789abcdef-0123456789abcdef-00"
+
 let () = test_of_value "00-4bf92f3577b34da6a3ce929d0e0e4736-00f067aa0ba902b7-01"
 
 let () = print_endline ""
 
 let test_to_value trace_id parent_id =
   let open Format in
-  printf "@[<v 2>Trace_context.Traceparent.to_value %a:@ %S@]@."
-    pp_traceparent (trace_id, parent_id)
+  printf "@[<v 2>Trace_context.Traceparent.to_value %a:@ %S@]@." pp_traceparent
+    (trace_id, parent_id)
     (Trace_context.Traceparent.to_value ~trace_id ~parent_id ())
 
-
-let () = test_to_value (Trace_id.of_hex "4bf92f3577b34da6a3ce929d0e0e4736") (Span_id.of_hex "00f067aa0ba902b7")
+let () =
+  test_to_value
+    (Trace_id.of_hex "4bf92f3577b34da6a3ce929d0e0e4736")
+    (Span_id.of_hex "00f067aa0ba902b7")