Add Signal.Decode module

For testing

src/client/signal.ml

@@ -42,3 +42,22 @@ module Encode = struct
              ())
          ~enc:Trace_service.encode_pb_export_trace_service_request
 end
+
+module Decode = struct
+  let resource_of_string ~dec s = Pbrt.Decoder.of_string s |> dec
+
+  let logs data =
+    (resource_of_string ~dec:Logs_service.decode_pb_export_logs_service_request
+       data)
+      .resource_logs
+
+  let metrics data =
+    (resource_of_string
+       ~dec:Metrics_service.decode_pb_export_metrics_service_request data)
+      .resource_metrics
+
+  let traces data =
+    (resource_of_string
+       ~dec:Trace_service.decode_pb_export_trace_service_request data)
+      .resource_spans
+end

src/client/signal.mli

@@ -27,3 +27,21 @@ module Encode : sig
 
       @param encoder provide an encoder state to reuse *)
 end
+
+(** Decode signals from protobuf encoded strings, received over the wire *)
+module Decode : sig
+  val logs : string -> Opentelemetry_proto.Logs.resource_logs list
+  (** [logs ls] is a protobuf encoded string of the logs [ls]
+
+      @param encoder provide an encoder state to reuse *)
+
+  val metrics : string -> Opentelemetry_proto.Metrics.resource_metrics list
+  (** [metrics ms] is a protobuf encoded string of the metrics [ms]
+
+      @param encoder provide an encoder state to reuse *)
+
+  val traces : string -> Opentelemetry_proto.Trace.resource_spans list
+  (** [metrics ts] is a protobuf encoded string of the traces [ts]
+
+      @param encoder provide an encoder state to reuse *)
+end