Add Vary support for ServiceWorkerCache::Match.

content/browser/service_worker/service_worker_cache.cc

Index: content/browser/service_worker/service_worker_cache.cc
diff --git a/content/browser/service_worker/service_worker_cache.cc b/content/browser/service_worker/service_worker_cache.cc
index 2fb5216d8f19a7c1ccd4ea561e894b3648adc446..cf92874e0fcedb912fca4c09c108b000050f726c 100644
--- a/content/browser/service_worker/service_worker_cache.cc
+++ b/content/browser/service_worker/service_worker_cache.cc
@@ -9,6 +9,7 @@
 #include "base/files/file_path.h"
 #include "base/guid.h"
 #include "base/message_loop/message_loop_proxy.h"
+#include "base/strings/string_util.h"
 #include "content/browser/service_worker/service_worker_cache.pb.h"
 #include "content/public/browser/browser_thread.h"
 #include "net/base/io_buffer.h"
@@ -29,6 +30,7 @@ typedef base::Callback<void(disk_cache::ScopedEntryPtr, bool)>
     EntryBoolCallback;
 typedef base::Callback<void(scoped_ptr<ServiceWorkerRequestResponseHeaders>)>
     HeadersCallback;
+typedef std::map<std::string, std::string> HeaderMap;
 
 enum EntryIndex { INDEX_HEADERS = 0, INDEX_RESPONSE_BODY };
 
@@ -373,6 +375,42 @@ void MatchDidOpenEntry(scoped_ptr<ServiceWorkerFetchRequest> request,
   ReadHeaders(tmp_entry_ptr, headers_callback);
 }
 
+bool VaryMatches(const HeaderMap& request,
+                 const HeaderMap& cached_request,
+                 const HeaderMap& response) {
+  // The headers are assumed to have lower-case keys. This is enforced by
+  // ASSERTS in WebServiceWorkerRequest and WebServiceWorkerResponse.

[jkarlin, 2014/09/17 18:48:10]

The ASSERTS this comment speaks of are in review:

https://codereview.chromium.org/564773004/ and
https://codereview.chromium.org/578763003/

+  HeaderMap::const_iterator vary_iter = response.find("vary");
+  if (vary_iter == response.end())
+    return true;
+
+  std::vector<std::string> vary_keys;
+  Tokenize(vary_iter->second, ",", &vary_keys);
+  for (size_t i = 0, max = vary_keys.size(); i < max; ++i) {
+    std::string trimmed;
+    base::TrimWhitespaceASCII(vary_keys[i], base::TRIM_ALL, &trimmed);
+    if (trimmed == "*")
+      return false;
+
+    HeaderMap::const_iterator request_iter = request.find(trimmed);
+    HeaderMap::const_iterator cached_request_iter =
+        cached_request.find(trimmed);
+
+    // If the header exists in one but not the other, no match.
+    if ((request_iter == request.end()) !=
+        (cached_request_iter == cached_request.end()))
+      return false;
+
+    // If the header exists in one, it exists in both. Verify that the values
+    // are equal.
+    if (request_iter != request.end() &&
+        request_iter->second != cached_request_iter->second)
+      return false;
+  }
+
+  return true;
+}
+
 void MatchDidReadHeaderData(
     scoped_ptr<ServiceWorkerFetchRequest> request,
     const ServiceWorkerCache::ResponseCallback& callback,
@@ -399,7 +437,21 @@ void MatchDidReadHeaderData(
     response->headers.insert(std::make_pair(header.name(), header.value()));
   }
 
-  // TODO(jkarlin): Insert vary validation here.
+  HeaderMap cached_request_headers;
+  for (int i = 0; i < headers->request_headers_size(); ++i) {
+    const ServiceWorkerRequestResponseHeaders::HeaderMap header =
+        headers->request_headers(i);
+    cached_request_headers.insert(
+        std::make_pair(header.name(), header.value()));
+  }
+
+  if (!VaryMatches(
+          request->headers, cached_request_headers, response->headers)) {
+    callback.Run(ServiceWorkerCache::ErrorTypeNotFound,
+                 scoped_ptr<ServiceWorkerResponse>(),
+                 scoped_ptr<storage::BlobDataHandle>());
+    return;
+  }
 
   if (entry->GetDataSize(INDEX_RESPONSE_BODY) == 0) {
     callback.Run(ServiceWorkerCache::ErrorTypeOK,