Add read-only access to POST data for webRequest's onBeforeRequest

chrome/browser/extensions/api/web_request/web_request_api.cc

Index: chrome/browser/extensions/api/web_request/web_request_api.cc
diff --git a/chrome/browser/extensions/api/web_request/web_request_api.cc b/chrome/browser/extensions/api/web_request/web_request_api.cc
index 2d8d8ad862d2cb5c7d27b3f3f3187f1bb5cf37b6..271e3a5994ac0b3af25bacbc35bcf60a62ca491b 100644
--- a/chrome/browser/extensions/api/web_request/web_request_api.cc
+++ b/chrome/browser/extensions/api/web_request/web_request_api.cc
@@ -19,6 +19,7 @@
 #include "chrome/browser/extensions/api/declarative_webrequest/webrequest_rule.h"
 #include "chrome/browser/extensions/api/declarative_webrequest/webrequest_rules_registry.h"
 #include "chrome/browser/extensions/api/web_navigation/web_navigation_api_helpers.h"
+#include "chrome/browser/extensions/api/web_request/post_data_parser.h"
 #include "chrome/browser/extensions/api/web_request/web_request_api_constants.h"
 #include "chrome/browser/extensions/api/web_request/web_request_api_helpers.h"
 #include "chrome/browser/extensions/api/web_request/web_request_time_tracker.h"
@@ -50,6 +51,7 @@
 #include "net/url_request/url_request.h"
 #include "ui/base/l10n/l10n_util.h"
 
+using chrome::VersionInfo;
 using content::BrowserMessageFilter;
 using content::BrowserThread;
 using content::ResourceRequestInfo;
@@ -63,7 +65,7 @@ namespace keys = extension_web_request_api_constants;
 namespace {
 
 // List of all the webRequest events.
-static const char* const kWebRequestEvents[] = {
+const char* const kWebRequestEvents[] = {
   keys::kOnBeforeRedirect,
   keys::kOnBeforeRequest,
   keys::kOnBeforeSendHeaders,
@@ -77,6 +79,20 @@ static const char* const kWebRequestEvents[] = {
 
 #define ARRAYEND(array) (array + arraysize(array))
 
+bool g_channel_cached = false;
+VersionInfo::Channel g_channel = VersionInfo::CHANNEL_UNKNOWN;
+
+// Access to request body (crbug.com/91191/) is currently only enabled in dev
+// and canary channels. This function caches the release channel info from
+// chrome::VersionInfo. Don't use this outside IO thread.
+bool IsWebRequestBodyDataAccessEnabled() {
+  if (!g_channel_cached) {
+    g_channel = VersionInfo::GetChannel();
+    g_channel_cached = true;
+  }
+  return g_channel <= VersionInfo::CHANNEL_DEV;
+}
+
 bool IsWebRequestEvent(const std::string& event_name) {
   return std::find(kWebRequestEvents, ARRAYEND(kWebRequestEvents),
                    event_name) != ARRAYEND(kWebRequestEvents);
@@ -157,6 +173,49 @@ void ExtractRequestInfo(net::URLRequest* request, DictionaryValue* out) {
   out->SetDouble(keys::kTimeStampKey, base::Time::Now().ToDoubleT() * 1000);
 }
 
+// Extracts the body from |request| and writes the data into |out|.
+void ExtractRequestInfoBody(const net::URLRequest* request,
+                            DictionaryValue* out) {
+  if (request->method() != "POST" && request->method() != "PUT")
+    return;  // Need to exit without "out->Set(keys::kBodyKey, ...);" .
+
+  DictionaryValue* body = new DictionaryValue();
+  out->Set(keys::kBodyKey, body);
+
+  // Get the data producers, ordered by being interesting.
+  extensions::ChunkedErrorProducer chunked_error_producer(request);
+  extensions::RawDataProducer raw_data_producer;
+  extensions::ParsedDataProducer parsed_data_producer(request);
+  extensions::RequestDataRepresentationProducer* const kProducers[] = {

[Matt Perry, 2012/08/06 21:06:45]

just "producers". While "const", this variable doesn't really represent a
"constant" value.

[vabr (Chromium), 2012/08/10 17:12:55]

Done.

+    &chunked_error_producer,  // First  -- any errors?
+    &parsed_data_producer,    // Second -- any parseable forms?
+    &raw_data_producer        // Third  -- any data at all?
+  };
+  // Keys for the results of the corresponding producers.
+  static const char* const kKeys[] = {
+    keys::kBodyErrorKey,
+    keys::kBodyParsedFormKey,
+    keys::kBodyRawKey
+  };
+
+  const std::vector<net::UploadData::Element>* elements =
+      request->get_upload()->elements();
+  bool some_succeeded = false;
+  for (size_t n = 0; !some_succeeded && n < arraysize(kProducers); ++n) {

[wtc, 2012/08/09 23:39:40]

Nit: this kind of for loop index variable is traditionally
named 'i'.  'n' usually is used for the number of elements.
(This convention probably comes from math and Fortran).

[vabr (Chromium), 2012/08/10 17:12:55]

Done.
I agree, Index versus Number (of).

+    std::vector<net::UploadData::Element>::const_iterator element;
+    for (element = elements->begin(); element != elements->end(); ++element) {
+      kProducers[n]->FeedNext(*element);
+    }
+    if (kProducers[n]->Succeeded()) {
+      body->Set(kKeys[n], kProducers[n]->Result().release());
+      some_succeeded = true;
+    }
+  }
+  if (!some_succeeded) {
+    body->SetString(keys::kBodyErrorKey, "Unknown error.");
+  }
+}
+
 // Converts a HttpHeaders dictionary to a |name|, |value| pair. Returns
 // true if successful.
 bool FromHeaderDictionary(const DictionaryValue* header_value,
@@ -251,6 +310,17 @@ void ClearCacheOnNavigationOnUI() {
 
 }  // namespace
 
+// Don't use this outside IO thread.
+void WebRequestSetChannelForTesting(VersionInfo::Channel channel) {
+  g_channel = channel;
+  g_channel_cached = true;
+}
+
+// Don't use this outside IO thread.
+void WebRequestResetChannelForTesting() {
+  g_channel_cached = false;
+}
+
 // Represents a single unique listener to an event, along with whatever filter
 // parameters and extra_info_spec were specified at the time the listener was
 // added.
@@ -409,6 +479,8 @@ bool ExtensionWebRequestEventRouter::ExtraInfoSpec::InitFromValue(
       *extra_info_spec |= BLOCKING;
     else if (str == "asyncBlocking")
       *extra_info_spec |= ASYNC_BLOCKING;
+    else if (str == "body")
+      *extra_info_spec |= IsWebRequestBodyDataAccessEnabled() ? BODY : 0;
     else
       return false;
 
@@ -498,6 +570,8 @@ int ExtensionWebRequestEventRouter::OnBeforeRequest(
     ListValue args;
     DictionaryValue* dict = new DictionaryValue();
     ExtractRequestInfo(request, dict);
+    if (extra_info_spec & ExtraInfoSpec::BODY)
+      ExtractRequestInfoBody(request, dict);
     args.Append(dict);
 
     initialize_blocked_requests |=