Streaming Trace, Part 2: simplify PipelineTracer to remove parentTracer

samples/tail-worker/config.capnp

@@ -0,0 +1,25 @@
+using Workerd = import "/workerd/workerd.capnp";
+
+const tailWorkerExample :Workerd.Config = (
+  services = [
+    (name = "main", worker = .helloWorld),
+    (name = "log", worker = .logWorker),
+  ],
+
+  sockets = [ ( name = "http", address = "*:8080", http = (), service = "main" ) ]
+);
+
+const helloWorld :Workerd.Worker = (
+  modules = [
+    (name = "worker", esModule = embed "worker.js")
+  ],
+  compatibilityDate = "2023-02-28",
+  logging = ( toService = "log" ),
+);
+
+const logWorker :Workerd.Worker = (
+  modules = [
+    (name = "worker", esModule = embed "tail.js")
+  ],
+  compatibilityDate = "2023-02-28",
+);

samples/tail-worker/tail.js

@@ -0,0 +1,9 @@
+// Copyright (c) 2017-2023 Cloudflare, Inc.
+// Licensed under the Apache 2.0 license found in the LICENSE file or at:
+//     https://opensource.org/licenses/Apache-2.0
+
+export default {
+  tail(traces) {
+    console.log(traces);
+  }
+};

samples/tail-worker/worker.js

@@ -0,0 +1,9 @@
+// Copyright (c) 2017-2023 Cloudflare, Inc.
+// Licensed under the Apache 2.0 license found in the LICENSE file or at:
+//     https://opensource.org/licenses/Apache-2.0
+
+export default {
+  async fetch(req, env) {
+    return new Response("Hello World\n");
+  }
+};

src/workerd/api/hibernatable-web-socket.c++

@@ -75,27 +75,27 @@ kj::Promise<WorkerInterface::CustomEvent::Result> HibernatableWebSocketCustomEve
   auto eventParameters = consumeParams();
 
   KJ_IF_SOME(t, incomingRequest->getWorkerTracer()) {
-    Trace::HibernatableWebSocketEventInfo::Type type =
-        [&]() -> Trace::HibernatableWebSocketEventInfo::Type {
+    trace::HibernatableWebSocketEventInfo::Type type =
+        [&]() -> trace::HibernatableWebSocketEventInfo::Type {
       KJ_SWITCH_ONEOF(eventParameters.eventType) {
         KJ_CASE_ONEOF(_, HibernatableSocketParams::Text) {
-          return Trace::HibernatableWebSocketEventInfo::Message{};
+          return trace::HibernatableWebSocketEventInfo::Message{};
         }
         KJ_CASE_ONEOF(data, HibernatableSocketParams::Data) {
-          return Trace::HibernatableWebSocketEventInfo::Message{};
+          return trace::HibernatableWebSocketEventInfo::Message{};
         }
         KJ_CASE_ONEOF(close, HibernatableSocketParams::Close) {
-          return Trace::HibernatableWebSocketEventInfo::Close{
+          return trace::HibernatableWebSocketEventInfo::Close{
             .code = close.code, .wasClean = close.wasClean};
         }
         KJ_CASE_ONEOF(_, HibernatableSocketParams::Error) {
-          return Trace::HibernatableWebSocketEventInfo::Error{};
+          return trace::HibernatableWebSocketEventInfo::Error{};
         }
       }
       KJ_UNREACHABLE;
     }();
 
-    t.setEventInfo(context.now(), Trace::HibernatableWebSocketEventInfo(kj::mv(type)));
+    t.setEventInfo(context.now(), trace::HibernatableWebSocketEventInfo(kj::mv(type)));
   }
 
   try {

src/workerd/api/queue.c++

@@ -531,7 +531,7 @@ kj::Promise<WorkerInterface::CustomEvent::Result> QueueCustomEventImpl::run(
   }
 
   KJ_IF_SOME(t, incomingRequest->getWorkerTracer()) {
-    t.setEventInfo(context.now(), Trace::QueueEventInfo(kj::mv(queueName), batchSize));
+    t.setEventInfo(context.now(), trace::QueueEventInfo(kj::mv(queueName), batchSize));
   }
 
   // Create a custom refcounted type for holding the queueEvent so that we can pass it to the