Merge pull request #31 from ELLIOTTCABLE/try-lwt-over-lwt-catch

Use try%lwt over Lwt.catch

dune-project

@@ -32,7 +32,8 @@
    (opentelemetry (= :version))
    (cohttp-lwt-unix :with-test)
    (odoc :with-doc)
-   (lwt (>= "5.3")))
+   (lwt (>= "5.3"))
+   lwt_ppx)
  (tags
   (instrumentation tracing opentelemetry datadog lwt)))
 
@@ -69,7 +70,7 @@
    (pbrt (>= 2.2))
    (odoc :with-doc)
    (lwt (>= "5.3"))
-   (lwt_ppx :with-test)
+   lwt_ppx
    cohttp-lwt
    cohttp-lwt-unix)
   (synopsis "Collector client for opentelemetry, using cohttp + lwt"))

opentelemetry-client-cohttp-lwt.opam

@@ -15,7 +15,7 @@ depends: [
   "pbrt" {>= "2.2"}
   "odoc" {with-doc}
   "lwt" {>= "5.3"}
-  "lwt_ppx" {with-test}
+  "lwt_ppx"
   "cohttp-lwt"
   "cohttp-lwt-unix"
 ]

opentelemetry-lwt.opam

@@ -15,6 +15,7 @@ depends: [
   "cohttp-lwt-unix" {with-test}
   "odoc" {with-doc}
   "lwt" {>= "5.3"}
+  "lwt_ppx"
 ]
 build: [
   ["dune" "subst"] {dev}

src/client-cohttp-lwt/dune

@@ -2,5 +2,6 @@
  (name opentelemetry_client_cohttp_lwt)
  (public_name opentelemetry-client-cohttp-lwt)
  (synopsis "Opentelemetry collector using cohttp+lwt+unix")
+ (preprocess (pps lwt_ppx))
  (libraries opentelemetry lwt cohttp-lwt cohttp-lwt-unix pbrt mtime
    mtime.clock.os))

src/client-cohttp-lwt/opentelemetry_client_cohttp_lwt.ml

@@ -105,11 +105,11 @@ end = struct
     let body = Cohttp_lwt.Body.of_string bod in
 
     let* r =
-      Lwt.catch
-        (fun () ->
-          let+ r = Httpc.post ~headers ~body uri in
-          Ok r)
-        (fun e -> Lwt.return @@ Error e)
+      try%lwt
+        let+ r = Httpc.post ~headers ~body uri in
+        Ok r
+      with e ->
+        Lwt.return @@ Error e
     in
     match r with
     | Error e ->

src/lwt/dune

@@ -2,4 +2,6 @@
  (name opentelemetry_lwt)
  (public_name opentelemetry-lwt)
  (synopsis "Lwt frontend for opentelemetry")
+ (preprocess
+  (pps lwt_ppx))
  (libraries lwt opentelemetry))

src/lwt/opentelemetry_lwt.ml

@@ -47,14 +47,13 @@ module Trace = struct
       in
       emit ?service_name [ span ]
     in
-    Lwt.catch
-      (fun () ->
-        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)
+    try%lwt
+      let* x = f scope in
+      let () = finally (Ok ()) in
+      Lwt.return x
+    with e ->
+      let () = finally (Error (Printexc.to_string e)) in
+      Lwt.fail e
 end
 
 module Metrics = struct