From 5b2f8a5a3a1eed742b4bbb430fde429d29b76e8c Mon Sep 17 00:00:00 2001
From: Chengzhong Wu <cwu631@bloomberg.net>
Date: Wed, 5 Mar 2025 10:20:03 +0000
Subject: [PATCH] inspector: add protocol methods retrieving sent/received data

Add protocol method `Network.dataSent` to buffer request data. And
expose protocol methods `Network.getRequestPostData` and
`Network.getResponseBody` allowing devtool to retrieve buffered data.
---
 doc/api/inspector.md                          |  14 ++
 lib/inspector.js                              |   1 +
 lib/internal/inspector/network.js             |  21 ++
 lib/internal/inspector/network_http.js        |  34 ++--
 lib/internal/inspector/network_undici.js      |  37 ++--
 src/inspector/network_agent.cc                | 189 +++++++++++++++---
 src/inspector/network_agent.h                 |  33 ++-
 src/inspector/node_protocol.pdl               |  21 ++
 .../test-inspector-emit-protocol-event.js     |   7 +-
 .../test-inspector-network-data-received.js   |  72 +++++--
 .../test-inspector-network-data-sent.js       | 136 +++++++++++++
 11 files changed, 480 insertions(+), 85 deletions(-)
 create mode 100644 test/parallel/test-inspector-network-data-sent.js

diff --git a/doc/api/inspector.md b/doc/api/inspector.md
index a056065f95820d..04c09f94cb7f65 100644
--- a/doc/api/inspector.md
+++ b/doc/api/inspector.md
@@ -524,6 +524,20 @@ This feature is only available with the `--experimental-network-inspection` flag
 Broadcasts the `Network.dataReceived` event to connected frontends, or buffers the data if
 `Network.streamResourceContent` command was not invoked for the given request yet.
 
+Also enables `Network.getResponseBody` command to retrieve the response data.
+
+### `inspector.Network.dataSent([params])`
+
+<!-- YAML
+added: REPLACEME
+-->
+
+* `params` {Object}
+
+This feature is only available with the `--experimental-network-inspection` flag enabled.
+
+Enables `Network.getRequestPostData` command to retrieve the request data.
+
 ### `inspector.Network.requestWillBeSent([params])`
 
 <!-- YAML
diff --git a/lib/inspector.js b/lib/inspector.js
index 62ca9253c5612a..7dc5746f422f74 100644
--- a/lib/inspector.js
+++ b/lib/inspector.js
@@ -214,6 +214,7 @@ const Network = {
   responseReceived: (params) => broadcastToFrontend('Network.responseReceived', params),
   loadingFinished: (params) => broadcastToFrontend('Network.loadingFinished', params),
   loadingFailed: (params) => broadcastToFrontend('Network.loadingFailed', params),
+  dataSent: (params) => broadcastToFrontend('Network.dataSent', params),
   dataReceived: (params) => broadcastToFrontend('Network.dataReceived', params),
 };
 
diff --git a/lib/internal/inspector/network.js b/lib/internal/inspector/network.js
index f46268ddc49621..a035f7cea119c2 100644
--- a/lib/internal/inspector/network.js
+++ b/lib/internal/inspector/network.js
@@ -6,6 +6,7 @@ const {
 } = primordials;
 
 const { now } = require('internal/perf/utils');
+const { MIMEType } = require('internal/mime');
 const kInspectorRequestId = Symbol('kInspectorRequestId');
 
 // https://chromedevtools.github.io/devtools-protocol/1-3/Network/#type-ResourceType
@@ -46,9 +47,29 @@ function getNextRequestId() {
   return `node-network-event-${++requestId}`;
 };
 
+function sniffMimeType(contentType) {
+  let mimeType;
+  let charset;
+  try {
+    const mimeTypeObj = new MIMEType(contentType);
+    mimeType = mimeTypeObj.essence || '';
+    charset = mimeTypeObj.params.get('charset') || '';
+  } catch {
+    mimeType = '';
+    charset = '';
+  }
+
+  return {
+    __proto__: null,
+    mimeType,
+    charset,
+  };
+}
+
 module.exports = {
   kInspectorRequestId,
   kResourceType,
   getMonotonicTime,
   getNextRequestId,
+  sniffMimeType,
 };
diff --git a/lib/internal/inspector/network_http.js b/lib/internal/inspector/network_http.js
index 24c3598fd61763..f2a372c61f9f7e 100644
--- a/lib/internal/inspector/network_http.js
+++ b/lib/internal/inspector/network_http.js
@@ -13,10 +13,10 @@ const {
   kResourceType,
   getMonotonicTime,
   getNextRequestId,
+  sniffMimeType,
 } = require('internal/inspector/network');
 const dc = require('diagnostics_channel');
 const { Network } = require('inspector');
-const { MIMEType } = require('internal/mime');
 
 const kRequestUrl = Symbol('kRequestUrl');
 
@@ -24,24 +24,32 @@ const kRequestUrl = Symbol('kRequestUrl');
 const convertHeaderObject = (headers = {}) => {
   // The 'host' header that contains the host and port of the URL.
   let host;
+  let charset;
+  let mimeType;
   const dict = {};
   for (const { 0: key, 1: value } of ObjectEntries(headers)) {
-    if (key.toLowerCase() === 'host') {
+    const lowerCasedKey = key.toLowerCase();
+    if (lowerCasedKey === 'host') {
       host = value;
     }
+    if (lowerCasedKey === 'content-type') {
+      const result = sniffMimeType(value);
+      charset = result.charset;
+      mimeType = result.mimeType;
+    }
     if (typeof value === 'string') {
       dict[key] = value;
     } else if (ArrayIsArray(value)) {
-      if (key.toLowerCase() === 'cookie') dict[key] = value.join('; ');
+      if (lowerCasedKey === 'cookie') dict[key] = value.join('; ');
       // ChromeDevTools frontend treats 'set-cookie' as a special case
       // https://github.com/ChromeDevTools/devtools-frontend/blob/4275917f84266ef40613db3c1784a25f902ea74e/front_end/core/sdk/NetworkRequest.ts#L1368
-      else if (key.toLowerCase() === 'set-cookie') dict[key] = value.join('\n');
+      else if (lowerCasedKey === 'set-cookie') dict[key] = value.join('\n');
       else dict[key] = value.join(', ');
     } else {
       dict[key] = String(value);
     }
   }
-  return [host, dict];
+  return [dict, host, charset, mimeType];
 };
 
 /**
@@ -52,7 +60,7 @@ const convertHeaderObject = (headers = {}) => {
 function onClientRequestCreated({ request }) {
   request[kInspectorRequestId] = getNextRequestId();
 
-  const { 0: host, 1: headers } = convertHeaderObject(request.getHeaders());
+  const { 0: headers, 1: host, 2: charset } = convertHeaderObject(request.getHeaders());
   const url = `${request.protocol}//${host}${request.path}`;
   request[kRequestUrl] = url;
 
@@ -60,6 +68,7 @@ function onClientRequestCreated({ request }) {
     requestId: request[kInspectorRequestId],
     timestamp: getMonotonicTime(),
     wallTime: DateNow(),
+    charset,
     request: {
       url,
       method: request.method,
@@ -95,16 +104,7 @@ function onClientResponseFinish({ request, response }) {
     return;
   }
 
-  let mimeType;
-  let charset;
-  try {
-    const mimeTypeObj = new MIMEType(response.headers['content-type']);
-    mimeType = mimeTypeObj.essence || '';
-    charset = mimeTypeObj.params.get('charset') || '';
-  } catch {
-    mimeType = '';
-    charset = '';
-  }
+  const { 0: headers, 2: charset, 3: mimeType } = convertHeaderObject(response.headers);
 
   Network.responseReceived({
     requestId: request[kInspectorRequestId],
@@ -114,7 +114,7 @@ function onClientResponseFinish({ request, response }) {
       url: request[kRequestUrl],
       status: response.statusCode,
       statusText: response.statusMessage ?? '',
-      headers: convertHeaderObject(response.headers)[1],
+      headers,
       mimeType,
       charset,
     },
diff --git a/lib/internal/inspector/network_undici.js b/lib/internal/inspector/network_undici.js
index faa0bc35ec0462..2cb6a0a8785323 100644
--- a/lib/internal/inspector/network_undici.js
+++ b/lib/internal/inspector/network_undici.js
@@ -1,7 +1,6 @@
 'use strict';
 
 const {
-  ArrayPrototypeFindIndex,
   DateNow,
 } = primordials;
 
@@ -10,10 +9,10 @@ const {
   kResourceType,
   getMonotonicTime,
   getNextRequestId,
+  sniffMimeType,
 } = require('internal/inspector/network');
 const dc = require('diagnostics_channel');
 const { Network } = require('inspector');
-const { MIMEType } = require('internal/mime');
 
 // Convert an undici request headers array to a plain object (Map<string, string>)
 function requestHeadersArrayToDictionary(headers) {
@@ -29,21 +28,30 @@ function requestHeadersArrayToDictionary(headers) {
 // Convert an undici response headers array to a plain object (Map<string, string>)
 function responseHeadersArrayToDictionary(headers) {
   const dict = {};
+  let charset;
+  let mimeType;
   for (let idx = 0; idx < headers.length; idx += 2) {
     const key = `${headers[idx]}`;
+    const lowerCasedKey = key.toLowerCase();
     const value = `${headers[idx + 1]}`;
     const prevValue = dict[key];
 
+    if (lowerCasedKey === 'content-type') {
+      const result = sniffMimeType(value);
+      charset = result.charset;
+      mimeType = result.mimeType;
+    }
+
     if (typeof prevValue === 'string') {
       // ChromeDevTools frontend treats 'set-cookie' as a special case
       // https://github.com/ChromeDevTools/devtools-frontend/blob/4275917f84266ef40613db3c1784a25f902ea74e/front_end/core/sdk/NetworkRequest.ts#L1368
-      if (key.toLowerCase() === 'set-cookie') dict[key] = `${prevValue}\n${value}`;
+      if (lowerCasedKey === 'set-cookie') dict[key] = `${prevValue}\n${value}`;
       else dict[key] = `${prevValue}, ${value}`;
     } else {
       dict[key] = value;
     }
   }
-  return dict;
+  return [dict, charset, mimeType];
 };
 
 /**
@@ -54,10 +62,15 @@ function responseHeadersArrayToDictionary(headers) {
 function onClientRequestStart({ request }) {
   const url = `${request.origin}${request.path}`;
   request[kInspectorRequestId] = getNextRequestId();
+
+  const headers = requestHeadersArrayToDictionary(request.headers);
+  const { charset } = sniffMimeType(headers);
+
   Network.requestWillBeSent({
     requestId: request[kInspectorRequestId],
     timestamp: getMonotonicTime(),
     wallTime: DateNow(),
+    charset,
     request: {
       url,
       method: request.method,
@@ -94,19 +107,7 @@ function onClientResponseHeaders({ request, response }) {
     return;
   }
 
-  let mimeType;
-  let charset;
-  try {
-    const contentTypeKeyIndex =
-      ArrayPrototypeFindIndex(response.headers, (header) => header.toString().toLowerCase() === 'content-type');
-    const contentType = contentTypeKeyIndex !== -1 ? response.headers[contentTypeKeyIndex + 1].toString() : '';
-    const mimeTypeObj = new MIMEType(contentType);
-    mimeType = mimeTypeObj.essence || '';
-    charset = mimeTypeObj.params.get('charset') || '';
-  } catch {
-    mimeType = '';
-    charset = '';
-  }
+  const { 0: headers, 1: charset, 2: mimeType } = responseHeadersArrayToDictionary(response.headers);
 
   const url = `${request.origin}${request.path}`;
   Network.responseReceived({
@@ -118,7 +119,7 @@ function onClientResponseHeaders({ request, response }) {
       url,
       status: response.statusCode,
       statusText: response.statusText,
-      headers: responseHeadersArrayToDictionary(response.headers),
+      headers,
       mimeType,
       charset,
     },
diff --git a/src/inspector/network_agent.cc b/src/inspector/network_agent.cc
index faa49ead94a698..496b5c41a0bfc2 100644
--- a/src/inspector/network_agent.cc
+++ b/src/inspector/network_agent.cc
@@ -1,4 +1,5 @@
 #include "network_agent.h"
+#include "debug_utils-inl.h"
 #include "inspector/protocol_helper.h"
 #include "network_inspector.h"
 #include "util-inl.h"
@@ -68,6 +69,20 @@ Maybe<int> ObjectGetInt(v8::Local<v8::Context> context,
   return Just(value.As<v8::Int32>()->Value());
 }
 
+// Get a protocol bool property from the object.
+Maybe<bool> ObjectGetBool(v8::Local<v8::Context> context,
+                          Local<Object> object,
+                          const char* property) {
+  HandleScope handle_scope(context->GetIsolate());
+  Local<Value> value;
+  if (!object->Get(context, OneByteString(context->GetIsolate(), property))
+           .ToLocal(&value) ||
+      !value->IsBoolean()) {
+    return Nothing<bool>();
+  }
+  return Just(value.As<v8::Boolean>()->Value());
+}
+
 // Get an object property from the object.
 MaybeLocal<v8::Object> ObjectGetObject(v8::Local<v8::Context> context,
                                        Local<Object> object,
@@ -134,10 +149,13 @@ std::unique_ptr<protocol::Network::Request> createRequestFromObject(
   if (!headers) {
     return {};
   }
+  bool has_post_data =
+      ObjectGetBool(context, request, "hasPostData").FromMaybe(false);
 
   return protocol::Network::Request::create()
       .setUrl(url)
       .setMethod(method)
+      .setHasPostData(has_post_data)
       .setHeaders(std::move(headers))
       .build();
 }
@@ -169,15 +187,10 @@ std::unique_ptr<protocol::Network::Response> createResponseFromObject(
     return {};
   }
 
-  protocol::String mimeType;
-  if (!ObjectGetProtocolString(context, response, "mimeType").To(&mimeType)) {
-    mimeType = protocol::String("");
-  }
-
-  protocol::String charset = protocol::String();
-  if (!ObjectGetProtocolString(context, response, "charset").To(&charset)) {
-    charset = protocol::String("");
-  }
+  protocol::String mimeType =
+      ObjectGetProtocolString(context, response, "mimeType").FromMaybe("");
+  protocol::String charset =
+      ObjectGetProtocolString(context, response, "charset").FromMaybe("");
 
   return protocol::Network::Response::create()
       .setUrl(url)
@@ -196,6 +209,7 @@ NetworkAgent::NetworkAgent(NetworkInspector* inspector,
   event_notifier_map_["responseReceived"] = &NetworkAgent::responseReceived;
   event_notifier_map_["loadingFailed"] = &NetworkAgent::loadingFailed;
   event_notifier_map_["loadingFinished"] = &NetworkAgent::loadingFinished;
+  event_notifier_map_["dataSent"] = &NetworkAgent::dataSent;
   event_notifier_map_["dataReceived"] = &NetworkAgent::dataReceived;
 }
 
@@ -225,23 +239,93 @@ protocol::DispatchResponse NetworkAgent::disable() {
   return protocol::DispatchResponse::Success();
 }
 
+protocol::DispatchResponse NetworkAgent::getRequestPostData(
+    const protocol::String& in_requestId, protocol::String* out_postData) {
+  auto request_entry = requests_.find(in_requestId);
+  if (request_entry == requests_.end()) {
+    // Request not found, ignore it.
+    return protocol::DispatchResponse::InvalidParams("Request not found");
+  }
+
+  if (!request_entry->second.is_request_finished) {
+    // Request not finished yet.
+    return protocol::DispatchResponse::InvalidParams(
+        "Request data is not finished yet");
+  }
+  if (request_entry->second.request_charset == Charset::kBinary) {
+    // The protocol does not support binary request bodies yet.
+    return protocol::DispatchResponse::ServerError(
+        "Unable to serialize binary request body");
+  }
+  // If the response is UTF-8, we return it as a concatenated string.
+  CHECK_EQ(request_entry->second.request_charset, Charset::kUTF8);
+
+  // Concat response bodies.
+  protocol::Binary buf =
+      protocol::Binary::concat(request_entry->second.request_data_blobs);
+  *out_postData = protocol::StringUtil::fromUTF8(buf.data(), buf.size());
+  return protocol::DispatchResponse::Success();
+}
+
+protocol::DispatchResponse NetworkAgent::getResponseBody(
+    const protocol::String& in_requestId,
+    protocol::String* out_body,
+    bool* out_base64Encoded) {
+  auto request_entry = requests_.find(in_requestId);
+  if (request_entry == requests_.end()) {
+    // Request not found, ignore it.
+    return protocol::DispatchResponse::InvalidParams("Request not found");
+  }
+
+  if (request_entry->second.is_streaming) {
+    // Streaming request, data is not buffered.
+    return protocol::DispatchResponse::InvalidParams(
+        "Response body of the request is been streamed");
+  }
+
+  if (!request_entry->second.is_response_finished) {
+    // Response not finished yet.
+    return protocol::DispatchResponse::InvalidParams(
+        "Response data is not finished yet");
+  }
+
+  // Concat response bodies.
+  protocol::Binary buf =
+      protocol::Binary::concat(request_entry->second.response_data_blobs);
+  if (request_entry->second.response_charset == Charset::kBinary) {
+    // If the response is binary, we return base64 encoded data.
+    *out_body = buf.toBase64();
+    *out_base64Encoded = true;
+  } else if (request_entry->second.response_charset == Charset::kUTF8) {
+    // If the response is UTF-8, we return it as a concatenated string.
+    *out_body = protocol::StringUtil::fromUTF8(buf.data(), buf.size());
+    *out_base64Encoded = false;
+  } else {
+    UNREACHABLE("Response charset not implemented");
+  }
+
+  requests_.erase(request_entry);
+  return protocol::DispatchResponse::Success();
+}
+
 protocol::DispatchResponse NetworkAgent::streamResourceContent(
     const protocol::String& in_requestId, protocol::Binary* out_bufferedData) {
-  if (!requests_.contains(in_requestId)) {
+  auto it = requests_.find(in_requestId);
+  if (it == requests_.end()) {
     // Request not found, ignore it.
     return protocol::DispatchResponse::InvalidParams("Request not found");
   }
+  auto& request_entry = it->second;
 
-  auto& it = requests_[in_requestId];
-
-  it.is_streaming = true;
+  request_entry.is_streaming = true;
 
   // Concat response bodies.
-  *out_bufferedData = protocol::Binary::concat(it.response_data_blobs);
+  *out_bufferedData =
+      protocol::Binary::concat(request_entry.response_data_blobs);
   // Clear buffered data.
-  it.response_data_blobs.clear();
+  request_entry.response_data_blobs.clear();
 
-  if (it.is_finished) {
+  if (request_entry.is_response_finished) {
     // If the request is finished, remove the entry.
     requests_.erase(in_requestId);
   }
@@ -263,6 +347,8 @@ void NetworkAgent::requestWillBeSent(v8::Local<v8::Context> context,
   if (!ObjectGetDouble(context, params, "wallTime").To(&wall_time)) {
     return;
   }
+  protocol::String charset =
+      ObjectGetProtocolString(context, params, "charset").FromMaybe("");
   Local<v8::Object> request_obj;
   if (!ObjectGetObject(context, params, "request").ToLocal(&request_obj)) {
     return;
@@ -280,17 +366,20 @@ void NetworkAgent::requestWillBeSent(v8::Local<v8::Context> context,
               v8_inspector_->captureStackTrace(true)->buildInspectorObject(0))
           .build();
 
+  if (requests_.contains(request_id)) {
+    // Duplicate entry, ignore it.
+    return;
+  }
+
+  auto request_charset = charset == "utf-8" ? Charset::kUTF8 : Charset::kBinary;
+  requests_.emplace(
+      request_id,
+      RequestEntry(timestamp, request_charset, request->getHasPostData()));
   frontend_->requestWillBeSent(request_id,
                                std::move(request),
                                std::move(initiator),
                                timestamp,
                                wall_time);
-
-  if (requests_.contains(request_id)) {
-    // Duplicate entry, ignore it.
-    return;
-  }
-  requests_.emplace(request_id, RequestEntry{timestamp, false, false, {}});
 }
 
 void NetworkAgent::responseReceived(v8::Local<v8::Context> context,
@@ -316,6 +405,13 @@ void NetworkAgent::responseReceived(v8::Local<v8::Context> context,
     return;
   }
 
+  auto request_entry = requests_.find(request_id);
+  if (request_entry == requests_.end()) {
+    // No entry found. Ignore it.
+    return;
+  }
+  request_entry->second.response_charset =
+      response->getCharset() == "utf-8" ? Charset::kUTF8 : Charset::kBinary;
   frontend_->responseReceived(request_id, timestamp, type, std::move(response));
 }
 
@@ -366,12 +462,12 @@ void NetworkAgent::loadingFinished(v8::Local<v8::Context> context,
     // Streaming finished, remove the entry.
     requests_.erase(request_id);
   } else {
-    request_entry->second.is_finished = true;
+    request_entry->second.is_response_finished = true;
   }
 }
 
-void NetworkAgent::dataReceived(v8::Local<v8::Context> context,
-                                v8::Local<v8::Object> params) {
+void NetworkAgent::dataSent(v8::Local<v8::Context> context,
+                            v8::Local<v8::Object> params) {
   protocol::String request_id;
   if (!ObjectGetProtocolString(context, params, "requestId").To(&request_id)) {
     return;
@@ -383,6 +479,39 @@ void NetworkAgent::dataReceived(v8::Local<v8::Context> context,
     return;
   }
 
+  bool is_finished =
+      ObjectGetBool(context, params, "finished").FromMaybe(false);
+  if (is_finished) {
+    request_entry->second.is_request_finished = true;
+    return;
+  }
+
+  double timestamp;
+  if (!ObjectGetDouble(context, params, "timestamp").To(&timestamp)) {
+    return;
+  }
+  int data_length;
+  if (!ObjectGetInt(context, params, "dataLength").To(&data_length)) {
+    return;
+  }
+  Local<Object> data_obj;
+  if (!ObjectGetObject(context, params, "data").ToLocal(&data_obj)) {
+    return;
+  }
+  if (!data_obj->IsUint8Array()) {
+    return;
+  }
+  Local<Uint8Array> data = data_obj.As<Uint8Array>();
+  auto data_bin = protocol::Binary::fromUint8Array(data);
+  request_entry->second.request_data_blobs.push_back(data_bin);
+}
+
+void NetworkAgent::dataReceived(v8::Local<v8::Context> context,
+                                v8::Local<v8::Object> params) {
+  protocol::String request_id;
+  if (!ObjectGetProtocolString(context, params, "requestId").To(&request_id)) {
+    return;
+  }
   double timestamp;
   if (!ObjectGetDouble(context, params, "timestamp").To(&timestamp)) {
     return;
@@ -406,11 +535,17 @@ void NetworkAgent::dataReceived(v8::Local<v8::Context> context,
   Local<Uint8Array> data = data_obj.As<Uint8Array>();
   auto data_bin = protocol::Binary::fromUint8Array(data);
 
-  if (request_entry->second.is_streaming) {
+  auto it = requests_.find(request_id);
+  if (it == requests_.end()) {
+    // No entry found. Ignore it.
+    return;
+  }
+  auto& request_entry = it->second;
+  if (request_entry.is_streaming) {
     frontend_->dataReceived(
         request_id, timestamp, data_length, encoded_data_length, data_bin);
   } else {
-    requests_[request_id].response_data_blobs.push_back(data_bin);
+    request_entry.response_data_blobs.push_back(data_bin);
   }
 }
 
diff --git a/src/inspector/network_agent.h b/src/inspector/network_agent.h
index 1229ae78044c3a..c5303885d61e18 100644
--- a/src/inspector/network_agent.h
+++ b/src/inspector/network_agent.h
@@ -11,11 +11,29 @@ namespace inspector {
 
 class NetworkInspector;
 
+// Supported charsets for devtools frontend on request/response data.
+// If the charset is kUTF8, the data is expected to be text and can be
+// formatted on the frontend.
+enum class Charset {
+  kUTF8,
+  kBinary,
+};
+
 struct RequestEntry {
   double timestamp;
-  bool is_finished;
-  bool is_streaming;
+  bool is_request_finished = false;
+  bool is_response_finished = false;
+  bool is_streaming = false;
+  Charset request_charset;
+  std::vector<protocol::Binary> request_data_blobs;
+  Charset response_charset;
   std::vector<protocol::Binary> response_data_blobs;
+
+  RequestEntry(double timestamp, Charset request_charset, bool has_request_body)
+      : timestamp(timestamp),
+        is_request_finished(!has_request_body),
+        request_charset(request_charset),
+        response_charset(Charset::kBinary) {}
 };
 
 class NetworkAgent : public protocol::Network::Backend {
@@ -29,6 +47,15 @@ class NetworkAgent : public protocol::Network::Backend {
 
   protocol::DispatchResponse disable() override;
 
+  protocol::DispatchResponse getRequestPostData(
+      const protocol::String& in_requestId,
+      protocol::String* out_postData) override;
+
+  protocol::DispatchResponse getResponseBody(
+      const protocol::String& in_requestId,
+      protocol::String* out_body,
+      bool* out_base64Encoded) override;
+
   protocol::DispatchResponse streamResourceContent(
       const protocol::String& in_requestId,
       protocol::Binary* out_bufferedData) override;
@@ -49,6 +76,8 @@ class NetworkAgent : public protocol::Network::Backend {
   void loadingFinished(v8::Local<v8::Context> context,
                        v8::Local<v8::Object> params);
 
+  void dataSent(v8::Local<v8::Context> context, v8::Local<v8::Object> params);
+
   void dataReceived(v8::Local<v8::Context> context,
                     v8::Local<v8::Object> params);
 
diff --git a/src/inspector/node_protocol.pdl b/src/inspector/node_protocol.pdl
index 148a0debe28da1..3608bfd317022c 100644
--- a/src/inspector/node_protocol.pdl
+++ b/src/inspector/node_protocol.pdl
@@ -165,6 +165,7 @@ experimental domain Network
       string url
       string method
       Headers headers
+      boolean hasPostData
 
   # HTTP response data.
   type Response extends object
@@ -185,6 +186,26 @@ experimental domain Network
   # Enables network tracking, network events will now be delivered to the client.
   command enable
 
+  # Returns post data sent with the request. Returns an error when no data was sent with the request.
+  command getRequestPostData
+    parameters
+      # Identifier of the network request to get content for.
+      RequestId requestId
+    returns
+      # Request body string, omitting files from multipart requests
+      string postData
+
+  # Returns content served for the given request.
+  command getResponseBody
+    parameters
+      # Identifier of the network request to get content for.
+      RequestId requestId
+    returns
+      # Response body.
+      string body
+      # True, if content was sent as base64.
+      boolean base64Encoded
+
   # Enables streaming of the response for the given requestId.
   # If enabled, the dataReceived event contains the data that was received during streaming.
   experimental command streamResourceContent
diff --git a/test/parallel/test-inspector-emit-protocol-event.js b/test/parallel/test-inspector-emit-protocol-event.js
index b539831f4399b6..5a90b258cd6e1a 100644
--- a/test/parallel/test-inspector-emit-protocol-event.js
+++ b/test/parallel/test-inspector-emit-protocol-event.js
@@ -63,7 +63,12 @@ const EXPECTED_EVENTS = {
     },
     {
       name: 'dataReceived',
-      // Network.dataReceived is buffered until Network.streamResourceContent is invoked.
+      // Network.dataReceived is buffered until Network.streamResourceContent/Network.getResponseBody is invoked.
+      skip: true,
+    },
+    {
+      name: 'dataSent',
+      // Network.dataSent is buffered until Network.getRequestPostData is invoked.
       skip: true,
     },
     {
diff --git a/test/parallel/test-inspector-network-data-received.js b/test/parallel/test-inspector-network-data-received.js
index fde584c885567a..466baf31c14c76 100644
--- a/test/parallel/test-inspector-network-data-received.js
+++ b/test/parallel/test-inspector-network-data-received.js
@@ -15,7 +15,7 @@ const session = new inspector.Session();
 session.connect();
 session.post('Network.enable');
 
-async function triggerNetworkEvents(requestId) {
+async function triggerNetworkEvents(requestId, charset) {
   const url = 'https://example.com';
   Network.requestWillBeSent({
     requestId,
@@ -42,6 +42,7 @@ async function triggerNetworkEvents(requestId) {
       headers: {
         mKey: 'mValue',
       },
+      charset,
     },
   });
   await setTimeout(1);
@@ -72,18 +73,30 @@ async function triggerNetworkEvents(requestId) {
   });
 }
 
+function assertNetworkEvents(session, requestId) {
+  session.on('Network.requestWillBeSent', common.mustCall(({ params }) => {
+    assert.strictEqual(params.requestId, requestId);
+  }));
+  session.on('Network.responseReceived', common.mustCall(({ params }) => {
+    assert.strictEqual(params.requestId, requestId);
+  }));
+  const loadingFinishedFuture = waitUntil(session, 'Network.loadingFinished')
+    .then(async ([{ params }]) => {
+      assert.strictEqual(params.requestId, requestId);
+    });
+
+  return loadingFinishedFuture;
+}
+
 test('should stream Network.dataReceived with data chunks', async () => {
   session.removeAllListeners();
 
   const requestId = 'my-req-id-1';
   const chunks = [];
   let totalDataLength = 0;
-  session.on('Network.requestWillBeSent', common.mustCall(({ params }) => {
-    assert.strictEqual(params.requestId, requestId);
-  }));
+  const loadingFinishedFuture = assertNetworkEvents(session, requestId);
   const responseReceivedFuture = waitUntil(session, 'Network.responseReceived')
-    .then(async ([{ params }]) => {
-      assert.strictEqual(params.requestId, requestId);
+    .then(async () => {
       const { bufferedData } = await session.post('Network.streamResourceContent', {
         requestId,
       });
@@ -91,10 +104,6 @@ test('should stream Network.dataReceived with data chunks', async () => {
       totalDataLength += data.byteLength;
       chunks.push(data);
     });
-  const loadingFinishedFuture = waitUntil(session, 'Network.loadingFinished')
-    .then(([{ params }]) => {
-      assert.strictEqual(params.requestId, requestId);
-    });
   session.on('Network.dataReceived', ({ params }) => {
     assert.strictEqual(params.requestId, requestId);
     totalDataLength += params.dataLength;
@@ -114,16 +123,7 @@ test('Network.streamResourceContent should send all buffered chunks', async () =
   session.removeAllListeners();
 
   const requestId = 'my-req-id-2';
-  session.on('Network.requestWillBeSent', common.mustCall(({ params }) => {
-    assert.strictEqual(params.requestId, requestId);
-  }));
-  session.on('Network.responseReceived', common.mustCall(({ params }) => {
-    assert.strictEqual(params.requestId, requestId);
-  }));
-  const loadingFinishedFuture = waitUntil(session, 'Network.loadingFinished')
-    .then(async ([{ params }]) => {
-      assert.strictEqual(params.requestId, requestId);
-    });
+  const loadingFinishedFuture = assertNetworkEvents(session, requestId);
   session.on('Network.dataReceived', common.mustNotCall());
 
   await triggerNetworkEvents(requestId);
@@ -144,3 +144,35 @@ test('Network.streamResourceContent should reject if request id not found', asyn
     code: 'ERR_INSPECTOR_COMMAND',
   });
 });
+
+test('Network.getResponseBody should send all buffered binary data', async () => {
+  session.removeAllListeners();
+
+  const requestId = 'my-req-id-3';
+  const loadingFinishedFuture = assertNetworkEvents(session, requestId);
+  session.on('Network.dataReceived', common.mustNotCall());
+
+  await triggerNetworkEvents(requestId);
+  await loadingFinishedFuture;
+  const { body, base64Encoded } = await session.post('Network.getResponseBody', {
+    requestId,
+  });
+  assert.strictEqual(base64Encoded, true);
+  assert.strictEqual(body, Buffer.from('Hello, world').toString('base64'));
+});
+
+test('Network.getResponseBody should send all buffered text data', async () => {
+  session.removeAllListeners();
+
+  const requestId = 'my-req-id-4';
+  const loadingFinishedFuture = assertNetworkEvents(session, requestId);
+  session.on('Network.dataReceived', common.mustNotCall());
+
+  await triggerNetworkEvents(requestId, 'utf-8');
+  await loadingFinishedFuture;
+  const { body, base64Encoded } = await session.post('Network.getResponseBody', {
+    requestId,
+  });
+  assert.strictEqual(base64Encoded, false);
+  assert.strictEqual(body, 'Hello, world');
+});
diff --git a/test/parallel/test-inspector-network-data-sent.js b/test/parallel/test-inspector-network-data-sent.js
new file mode 100644
index 00000000000000..5c28c1935af4ed
--- /dev/null
+++ b/test/parallel/test-inspector-network-data-sent.js
@@ -0,0 +1,136 @@
+// Flags: --inspect=0 --experimental-network-inspection
+'use strict';
+const common = require('../common');
+
+common.skipIfInspectorDisabled();
+
+const inspector = require('node:inspector/promises');
+const { Network } = require('node:inspector');
+const test = require('node:test');
+const assert = require('node:assert');
+const { waitUntil } = require('../common/inspector-helper');
+const { setTimeout } = require('node:timers/promises');
+
+const session = new inspector.Session();
+session.connect();
+session.post('Network.enable');
+
+async function triggerNetworkEvents(requestId, requestCharset) {
+  const url = 'https://example.com';
+  Network.requestWillBeSent({
+    requestId,
+    timestamp: 1,
+    wallTime: 1,
+    request: {
+      url,
+      method: 'PUT',
+      headers: {
+        mKey: 'mValue',
+      },
+      hasPostData: true,
+    },
+    charset: requestCharset,
+  });
+  await setTimeout(1);
+
+  const chunk1 = Buffer.from('Hello, ');
+  Network.dataSent({
+    requestId,
+    timestamp: 2,
+    dataLength: chunk1.byteLength,
+    data: chunk1,
+  });
+  await setTimeout(1);
+
+  const chunk2 = Buffer.from('world');
+  Network.dataSent({
+    requestId,
+    timestamp: 3,
+    dataLength: chunk2.byteLength,
+    data: chunk2,
+  });
+  await setTimeout(1);
+
+  Network.dataSent({
+    requestId,
+    finished: true,
+  });
+  await setTimeout(1);
+
+  Network.responseReceived({
+    requestId,
+    timestamp: 4,
+    type: 'Fetch',
+    response: {
+      url,
+      status: 200,
+      statusText: 'OK',
+      headers: {
+        mKey: 'mValue',
+      },
+    },
+  });
+  await setTimeout(1);
+
+  Network.loadingFinished({
+    requestId,
+    timestamp: 5,
+  });
+}
+
+function assertNetworkEvents(session, requestId) {
+  session.on('Network.requestWillBeSent', common.mustCall(({ params }) => {
+    assert.strictEqual(params.requestId, requestId);
+  }));
+  session.on('Network.responseReceived', common.mustCall(({ params }) => {
+    assert.strictEqual(params.requestId, requestId);
+  }));
+  const loadingFinishedFuture = waitUntil(session, 'Network.loadingFinished')
+    .then(async ([{ params }]) => {
+      assert.strictEqual(params.requestId, requestId);
+    });
+
+  return loadingFinishedFuture;
+}
+
+test('Network.getRequestPostData should send all buffered text data', async () => {
+  session.removeAllListeners();
+
+  const requestId = 'my-req-id-1';
+  const loadingFinishedFuture = assertNetworkEvents(session, requestId);
+
+  await triggerNetworkEvents(requestId, 'utf-8');
+  await loadingFinishedFuture;
+
+  const { postData } = await session.post('Network.getRequestPostData', {
+    requestId,
+  });
+  assert.strictEqual(postData, 'Hello, world');
+});
+
+test('Network.getRequestPostData does not support binary data', async () => {
+  session.removeAllListeners();
+
+  const requestId = 'my-req-id-2';
+  const loadingFinishedFuture = assertNetworkEvents(session, requestId);
+
+  await triggerNetworkEvents(requestId);
+  await loadingFinishedFuture;
+
+  await assert.rejects(session.post('Network.getRequestPostData', {
+    requestId,
+  }), {
+    code: 'ERR_INSPECTOR_COMMAND',
+  });
+});
+
+test('Network.getRequestPostData should reject if request id not found', async () => {
+  session.removeAllListeners();
+
+  const requestId = 'unknown-request-id';
+  await assert.rejects(session.post('Network.getRequestPostData', {
+    requestId,
+  }), {
+    code: 'ERR_INSPECTOR_COMMAND',
+  });
+});