Merge "Log X-Google fields on failed HTTP requests."

libwvdrmengine/cdm/core/test/url_request.cpp

@@ -21,6 +21,10 @@ const int kConnectTimeoutMs = 15000;
 const int kWriteTimeoutMs = 12000;
 const int kReadTimeoutMs = 12000;
 
+const std::string kGoogleHeaderUpper("X-Google");
+const std::string kGoogleHeaderLower("x-google");
+const std::string kCrLf("\r\n");
+
 // Concatenate all chunks into one blob and returns the response with
 // header information.
 void ConcatenateChunkedResponse(const std::string http_response,
@@ -48,7 +52,6 @@ void ConcatenateChunkedResponse(const std::string http_response,
     // chunk size\r\n
     // chunk data\r\n
     // 0\r\n
-    const std::string kCrLf = "\r\n";
     size_t chunk_pos = http_response.find(kCrLf, chunk_size_pos);
     modified_response->assign(http_response, 0, chunk_size_pos);
 
@@ -131,6 +134,45 @@ int UrlRequest::GetStatusCode(const std::string& response) {
   return status_code;
 }
 
+// static
+bool UrlRequest::GetDebugHeaderFields(
+    const std::string& response, std::map<std::string, std::string>* fields) {
+  if (fields == nullptr) return false;
+  fields->clear();
+
+  const auto find_next = [&](size_t pos) -> size_t {
+    // Some of Google's HTTPS return header fields in lower case,
+    // this lambda will check for both and return the position that
+    // that is next or npos if none are found.
+    const size_t lower_pos = response.find(kGoogleHeaderLower, pos + 1);
+    const size_t upper_pos = response.find(kGoogleHeaderUpper, pos + 1);
+    if (lower_pos == std::string::npos) return upper_pos;
+    if (upper_pos == std::string::npos || lower_pos < upper_pos)
+      return lower_pos;
+    return upper_pos;
+  };
+
+  // Search is relatively simple, and may pick up additional matches within
+  // the body of the request.  This is not anticiapted for the limited use
+  // cases of parsing provisioning/license/renewal responses.
+  for (size_t key_pos = find_next(0); key_pos != std::string::npos;
+       key_pos = find_next(key_pos)) {
+    const size_t end_key_pos = response.find(":", key_pos);
+    const size_t end_value_pos = response.find(kCrLf, key_pos);
+    // Skip if the colon cannot be found.  Technically possible to find
+    // "X-Google" inside the value of a nother header field.
+    if (end_key_pos == std::string::npos || end_value_pos == std::string::npos)
+      continue;
+    const size_t value_pos = end_key_pos + 2;
+    if (end_value_pos < value_pos) continue;
+    const std::string key = response.substr(key_pos, end_key_pos - key_pos);
+    const std::string value =
+        response.substr(value_pos, end_value_pos - value_pos);
+    fields->insert({key, value});
+  }
+  return !fields->empty();
+}
+
 bool UrlRequest::PostRequestWithPath(const std::string& path,
                                      const std::string& data) {
   std::string request;

libwvdrmengine/cdm/core/test/url_request.h

@@ -5,7 +5,9 @@
 #ifndef CDM_TEST_URL_REQUEST_H_
 #define CDM_TEST_URL_REQUEST_H_
 
+#include <map>
 #include <string>
+
 #include "disallow_copy_and_assign.h"
 #include "http_socket.h"
 
@@ -27,6 +29,10 @@ class UrlRequest {
   bool GetResponse(std::string* message);
   static int GetStatusCode(const std::string& response);
 
+  static bool GetDebugHeaderFields(
+      const std::string& response,
+      std::map<std::string, std::string>* header_fields);
+
  private:
   bool PostRequestWithPath(const std::string& path, const std::string& data);
 

libwvdrmengine/cdm/core/test/url_request_unittest.cpp

@@ -0,0 +1,104 @@
+// Copyright 2020 Google LLC. All Rights Reserved. This file and proprietary
+// source code may only be used and distributed under the Widevine Master
+// License Agreement.
+
+#include "url_request.h"
+
+#include <gmock/gmock.h>
+#include <gtest/gtest.h>
+
+#include "test_base.h"
+
+namespace wvcdm {
+
+namespace {
+
+// A sample HTTP response which contains an HTTP header with several
+// standard and non-standard header fields.  The fields of interests
+// those beginning with "X-Google-" or "x-google-".
+const std::string kSampleResponse =
+    "HTTP/2 301\r\n"
+    "Location: https://www.google.com/\r\b"
+    "Content-Type: text/html; charset=UTF-8\r\n"
+    "X-Google-GFE-Backend-Request-Info: eid=7js14zjC48OpziR0VCF02a0\r\n"
+    "x-google-signals: FRAMEWORK=TEST\r\n"
+    "X-Google-Binary-Version: 322287520\r\n"
+    "X-Google-Request-Cost: 2.50\r\n"
+    "Date: Thu, 23 Jul 2020 22:52:55 GMT\r\n"
+    "Expires: Sat, 22 Aug 2020 22:52:55 GMT\r\n"
+    "Cache-Control: public, max-age=2592000\r\n"
+    "x-google-data-version: 322866295\r\n"
+    "Server: gws\r\n"
+    "X-Google-Debug-Label: /srv/alt/job/service.number/1380\r\n"
+    "Content-Length: 220\r\n"
+    "X-XSS-Protection: 0\r\n"
+    "X-Frame-Options: SAMEORIGIN\r\n"
+    "X-Google-Service: web\r\n"
+    "X-Google-DOS-Service-Trace: main:home\r\n"
+    "Alt-Svc: h3-29=\":443\"; ma=2592000,h3-27=\":443\"; "
+    "ma=2592000,h3-25=\":443\"; ma=2592000,h3-T050=\":443\"; "
+    "ma=2592000,h3-Q050=\":443\"; ma=2592000,h3-Q046=\":443\"; "
+    "ma=2592000,h3-Q043=\":443\"; ma=2592000,quic=\":443\"; ma=2592000; "
+    "v=\"46,43\"\r\n"
+    "\r\n"
+    "<HTML><HEAD><meta http-equiv=\"content-type\" "
+    "content=\"text/html;charset=utf-8\">\r\n"
+    "<TITLE>301 Moved</TITLE></HEAD><BODY>\r\n"
+    "<H1>301 Moved</H1>\r\n"
+    "The document has moved\r\n"
+    "<A HREF=\"https://www.google.com/\">here</A>.\r\n"
+    "</BODY></HTML>\r\n\r\n";
+
+// A map containing all the Google debug header fields found in
+// |kSampleResponse|.
+const std::map<std::string, std::string> kSampleFields = {
+    {"X-Google-GFE-Backend-Request-Info", "eid=7js14zjC48OpziR0VCF02a0"},
+    {"x-google-signals", "FRAMEWORK=TEST"},
+    {"X-Google-Binary-Version", "322287520"},
+    {"X-Google-Request-Cost", "2.50"},
+    {"x-google-data-version", "322866295"},
+    {"X-Google-Debug-Label", "/srv/alt/job/service.number/1380"},
+    {"X-Google-Service", "web"},
+    {"X-Google-DOS-Service-Trace", "main:home"}};
+
+// A sample HTTP response which does not contain any special header fields.
+const std::string kFieldlessResponse =
+    "HTTP/2 301\r\n"
+    "Location: https://www.google.com/\r\b"
+    "Content-Type: text/html; charset=UTF-8\r\n"
+    "Date: Thu, 23 Jul 2020 22:52:55 GMT\r\n"
+    "Content-Length: 220\r\n"
+    "\r\n"
+    "<HTML><HEAD><meta http-equiv=\"content-type\" "
+    "content=\"text/html;charset=utf-8\">\r\n"
+    "<TITLE>301 Moved</TITLE></HEAD><BODY>\r\n"
+    "<H1>301 Moved</H1>\r\n"
+    "The document has moved\r\n"
+    "<A HREF=\"https://www.google.com/\">here</A>.\r\n"
+    "</BODY></HTML>\r\n\r\n";
+
+}  // namespace
+
+class UrlRequestTest : public WvCdmTestBase {
+ protected:
+  void SetUp() override { WvCdmTestBase::SetUp(); }
+  void TearDown() override {}
+};
+
+TEST_F(UrlRequestTest, ParseDebugHeader) {
+  // Output map cannot be null.
+  EXPECT_FALSE(UrlRequest::GetDebugHeaderFields(kSampleResponse, nullptr));
+  std::map<std::string, std::string> fields;
+  // Expect false if no debug information can be determined.
+  EXPECT_FALSE(UrlRequest::GetDebugHeaderFields(kFieldlessResponse, &fields));
+  // Expect success.
+  EXPECT_TRUE(UrlRequest::GetDebugHeaderFields(kSampleResponse, &fields));
+  EXPECT_EQ(kSampleFields.size(), fields.size());
+  for (auto it = kSampleFields.cbegin(); it != kSampleFields.cend(); ++it) {
+    auto field = fields.find(it->first);
+    EXPECT_NE(fields.end(), field);
+    EXPECT_EQ(it->second, field->second) << "Key: \"" << it->first << "\"";
+  }
+}
+
+}  // namespace wvcdm