Update packages/sync-service/lib/electric/plug/trace_context_plug.ex

Co-authored-by: Ilia Borovitinov <[email protected]>

packages/sync-service/lib/electric/plug/trace_context_plug.ex

@@ -8,51 +8,21 @@ defmodule Electric.Plug.TraceContextPlug do
 
   def init(opts), do: opts
 
-  def call(conn, _opts) do
-    case extract_trace_context(conn) do
-      {:ok, span_ctx} ->
-        :otel_tracer.set_current_span(span_ctx)
-        conn
-
-      :error ->
-        conn
-    end
-  end
-
-  # Extract trace context using the OpenTelemetry propagator
-  defp extract_trace_context(conn) do
-    # Get all headers as a list of {key, value} tuples
-    headers =
-      conn
-      |> Plug.Conn.get_req_header("traceparent")
-      |> Enum.map(fn value -> {"traceparent", value} end)
-
-    # Create a new context and extract the trace context from headers
-    ctx =
-      :otel_propagator_trace_context.extract(
-        :otel_ctx.new(),
-        headers,
-        :undefined,
-        &header_getter/2,
-        %{}
-      )
+  def call(%Plug.Conn{req_headers: headers} = conn, _opts) do
+    # Extract function expects a list of headers as tuples and knows
+    # the expected header keys, so we don't have to prefilter.
+    ctx = :otel_propagator_text_map.extract_to(:otel_ctx.new(), headers)
 
     # Get the span context from the extracted context
     case :otel_tracer.current_span_ctx(ctx) do
-      :undefined -> :error
-      span_ctx -> {:ok, span_ctx}
-    end
-  end
+      :undefined ->
+        # No parent, continue as-is
+        conn
 
-  # Header getter function for the propagator
-  # Note: The key is passed first, carrier second by the propagator
-  defp header_getter(key, carrier) when is_list(carrier) do
-    case Enum.find(carrier, fn {k, _v} -> String.downcase(k) == String.downcase(key) end) do
-      {_key, value} -> value
-      nil -> []
+      span_ctx ->
+        # Parent found, set as current span
+        :otel_tracer.set_current_span(span_ctx)
+        conn
     end
   end
-
-  # Fallback clause for when carrier is not a list
-  defp header_getter(_key, _carrier), do: []
 end