inspector: support for worker inspection in chrome devtools

doc/api/cli.md

@@ -1136,6 +1136,17 @@ added: v22.4.0
 
 Enable experimental [`Web Storage`][] support.
 
+### `--experimental-worker-inspection`
+
+<!-- YAML
+added:
+  - v22.13.1
+-->
+
+> Stability: 1 - Experimental
+
+Enable experimental support for the worker inspection with Chrome DevTools.
+
 ### `--expose-gc`
 
 <!-- YAML

src/inspector/main_thread_interface.h

@@ -57,6 +57,10 @@ class MainThreadHandle : public std::enable_shared_from_this<MainThreadHandle> {
   std::unique_ptr<InspectorSessionDelegate> MakeDelegateThreadSafe(
       std::unique_ptr<InspectorSessionDelegate> delegate);
   bool Expired();
+  void SetTargetSessionId(int target_session_id) {
+    target_session_id_ = target_session_id;
+  }
+  std::optional<int> GetTargetSessionId() { return target_session_id_; }
 
  private:
   void Reset();
@@ -65,6 +69,7 @@ class MainThreadHandle : public std::enable_shared_from_this<MainThreadHandle> {
   Mutex block_lock_;
   int next_session_id_ = 0;
   std::atomic_int next_object_id_ = {1};
+  std::optional<int> target_session_id_ = std::nullopt;
 
   friend class MainThreadInterface;
 };

src/inspector/node_inspector.gypi

@@ -30,6 +30,9 @@
       'src/inspector/network_inspector.h',
       'src/inspector/network_agent.cc',
       'src/inspector/network_agent.h',
+      'src/inspector/network_agent.h',
+      'src/inspector/target_agent.cc',
+      'src/inspector/target_agent.h',
       'src/inspector/worker_inspector.cc',
       'src/inspector/worker_inspector.h',
     ],
@@ -45,6 +48,8 @@
       '<(SHARED_INTERMEDIATE_DIR)/src/node/inspector/protocol/NodeRuntime.h',
       '<(SHARED_INTERMEDIATE_DIR)/src/node/inspector/protocol/Network.cpp',
       '<(SHARED_INTERMEDIATE_DIR)/src/node/inspector/protocol/Network.h',
+      '<(SHARED_INTERMEDIATE_DIR)/src/node/inspector/protocol/Target.cpp',
+      '<(SHARED_INTERMEDIATE_DIR)/src/node/inspector/protocol/Target.h',
     ],
     'node_protocol_files': [
       '<(protocol_tool_path)/lib/Forward_h.template',

src/inspector/node_protocol.pdl

@@ -220,3 +220,28 @@ experimental domain NodeRuntime
   # This event is fired when the runtime is waiting for the debugger. For
   # example, when inspector.waitingForDebugger is called
   event waitingForDebugger
+
+# https://chromedevtools.github.io/devtools-protocol/1-3/Target/
+experimental domain Target
+  type SessionID extends string
+  type TargetID extends string
+  type TargetInfo extends object
+    properties
+      TargetID targetId
+      string type
+      string title
+      string url
+      boolean attached
+      boolean canAccessOpener
+  event targetCreated
+    parameters
+      TargetInfo targetInfo
+  event attachedToTarget
+    parameters
+      SessionID sessionId
+      TargetInfo targetInfo
+      boolean waitingForDebugger
+  command setAutoAttach
+    parameters
+      boolean autoAttach
+      boolean waitForDebuggerOnStart

src/inspector/target_agent.cc

@@ -0,0 +1,134 @@
+#include "target_agent.h"
+#include "crdtp/dispatch.h"
+#include "inspector/worker_inspector.h"
+#include "main_thread_interface.h"
+
+namespace node {
+namespace inspector {
+namespace protocol {
+
+std::unordered_map<int, std::shared_ptr<MainThreadHandle>>
+    TargetAgent::target_session_id_worker_map_ =
+        std::unordered_map<int, std::shared_ptr<MainThreadHandle>>();
+int TargetAgent::next_session_id_ = 1;
+class WorkerTargetDelegate : public WorkerDelegate {
+ public:
+  explicit WorkerTargetDelegate(std::shared_ptr<TargetAgent> target_agent)
+      : target_agent_(target_agent) {}
+
+  void WorkerCreated(const std::string& title,
+                     const std::string& url,
+                     bool waiting,
+                     std::shared_ptr<MainThreadHandle> worker) override {
+    target_agent_->createAndAttachIfNecessary(worker, title, url);
+  }
+
+ private:
+  const std::shared_ptr<TargetAgent> target_agent_;
+};
+
+std::unique_ptr<Target::TargetInfo> createTargetInfo(const String& target_id,
+                                                     const String& type,
+                                                     const String& title,
+                                                     const String& url) {
+  return Target::TargetInfo::create()
+      .setTargetId(target_id)
+      .setType(type)
+      .setTitle(title)
+      .setUrl(url)
+      .setAttached(false)
+      .setCanAccessOpener(true)
+      .build();
+}
+
+void TargetAgent::Wire(UberDispatcher* dispatcher) {
+  frontend_ = std::make_unique<Target::Frontend>(dispatcher->channel());
+  Target::Dispatcher::wire(dispatcher, this);
+}
+
+void TargetAgent::createAndAttachIfNecessary(
+    std::shared_ptr<MainThreadHandle> worker,
+    const std::string& title,
+    const std::string& url) {
+  std::string target_id = std::to_string(getNextTargetId());
+  std::string type = "worker";
+
+  targetCreated(target_id, type, title, url);
+  bool attached = false;
+  if (auto_attach_) {
+    attached = true;
+    attachedToTarget(worker, target_id, type, title, url);
+  }
+  targets_.push_back({target_id, type, title, url, worker, attached});
+}
+
+void TargetAgent::listenWorker(std::weak_ptr<WorkerManager> worker_manager) {
+  auto manager = worker_manager.lock();
+  if (!manager) {
+    return;
+  }
+  std::unique_ptr<WorkerDelegate> delegate(
+      new WorkerTargetDelegate(shared_from_this()));
+  worker_event_handle_ = manager->SetAutoAttach(std::move(delegate));
+}
+
+void TargetAgent::reset() {
+  if (worker_event_handle_) {
+    worker_event_handle_.reset();
+  }
+}
+
+void TargetAgent::targetCreated(const std::string& target_id,
+                                const std::string& type,
+                                const std::string& title,
+                                const std::string& url) {
+  frontend_->targetCreated(createTargetInfo(target_id, type, title, url));
+}
+
+int TargetAgent::getNextSessionId() {
+  return next_session_id_++;
+}
+
+int TargetAgent::getNextTargetId() {
+  return next_target_id_++;
+}
+
+void TargetAgent::attachedToTarget(std::shared_ptr<MainThreadHandle> worker,
+                                   const std::string& target_id,
+                                   const std::string& type,
+                                   const std::string& title,
+                                   const std::string& url) {
+  int session_id = getNextSessionId();
+  target_session_id_worker_map_[session_id] = worker;
+  worker->SetTargetSessionId(session_id);
+  frontend_->attachedToTarget(std::to_string(session_id),
+                              createTargetInfo(target_id, type, title, url),
+                              true);
+}
+
+// TODO(islandryu): Currently, setAutoAttach applies the main thread's value to
+// all threads. Modify it to be managed per worker thread.
+crdtp::DispatchResponse TargetAgent::setAutoAttach(
+    bool auto_attach, bool wait_for_debugger_on_start) {
+  auto_attach_ = auto_attach;
+  wait_for_debugger_on_start_ = wait_for_debugger_on_start;
+
+  if (auto_attach) {
+    for (auto& target : targets_) {
+      if (!target.attached) {
+        target.attached = true;
+        attachedToTarget(target.worker,
+                         target.target_id,
+                         target.type,
+                         target.title,
+                         target.url);
+      }
+    }
+  }
+
+  return DispatchResponse::Success();
+}
+
+}  // namespace protocol
+}  // namespace inspector
+}  // namespace node

src/inspector/target_agent.h

@@ -0,0 +1,73 @@
+#ifndef SRC_INSPECTOR_TARGET_AGENT_H_
+#define SRC_INSPECTOR_TARGET_AGENT_H_
+
+#include <unordered_map>
+#include <vector>
+#include "inspector/worker_inspector.h"
+#include "node/inspector/protocol/Target.h"
+
+namespace node {
+
+namespace inspector {
+class TargetInspector;
+
+namespace protocol {
+
+struct TargetInfo {
+  std::string target_id;
+  std::string type;
+  std::string title;
+  std::string url;
+  std::shared_ptr<MainThreadHandle> worker;
+  bool attached;
+};
+
+class TargetAgent : public Target::Backend,
+                    public std::enable_shared_from_this<TargetAgent> {
+ public:
+  void Wire(UberDispatcher* dispatcher);
+
+  void createAndAttachIfNecessary(std::shared_ptr<MainThreadHandle> worker,
+                                  const std::string& title,
+                                  const std::string& url);
+
+  DispatchResponse setAutoAttach(bool auto_attach,
+                                 bool wait_for_debugger_on_start) override;
+
+  void listenWorker(std::weak_ptr<WorkerManager> worker_manager);
+  void reset();
+  static std::unordered_map<int, std::shared_ptr<MainThreadHandle>>
+      target_session_id_worker_map_;
+
+  bool isThisThread(MainThreadHandle* worker) { return worker == main_thread_; }
+
+ private:
+  int getNextTargetId();
+  int getNextSessionId();
+  void targetCreated(const std::string& target_id,
+                     const std::string& type,
+                     const std::string& title,
+                     const std::string& url);
+  void attachedToTarget(std::shared_ptr<MainThreadHandle> worker,
+                        const std::string& target_id,
+                        const std::string& type,
+                        const std::string& title,
+                        const std::string& url);
+  std::shared_ptr<Target::Frontend> frontend_;
+  std::weak_ptr<WorkerManager> worker_manager_;
+  static int next_session_id_;
+  int next_target_id_ = 1;
+  std::unique_ptr<WorkerManagerEventHandle> worker_event_handle_ = nullptr;
+  bool auto_attach_ = false;
+  // TODO(islandryu): If false, implement it so that each thread does not wait
+  // for the worker to execute.
+  bool wait_for_debugger_on_start_ = true;
+  std::vector<TargetInfo> targets_;
+  MainThreadHandle* main_thread_;
+};
+
+}  // namespace protocol
+}  // namespace inspector
+}  // namespace node
+
+#endif  // SRC_INSPECTOR_TARGET_AGENT_H_