Initial version of Blimp BlobCache.

blimp/common/blob_cache/blob_cache.h

Index: blimp/common/blob_cache/blob_cache.h
diff --git a/blimp/common/blob_cache/blob_cache.h b/blimp/common/blob_cache/blob_cache.h
new file mode 100644
index 0000000000000000000000000000000000000000..54993238b5736dae585b91ef0e6e20de4e5c4c79
--- /dev/null
+++ b/blimp/common/blob_cache/blob_cache.h
@@ -0,0 +1,38 @@
+// Copyright 2016 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef BLIMP_COMMON_BLOB_CACHE_BLOB_CACHE_H_
+#define BLIMP_COMMON_BLOB_CACHE_BLOB_CACHE_H_
+
+#include <string>
+#include <vector>
+
+#include "base/memory/ref_counted.h"
+#include "blimp/common/blimp_common_export.h"
+
+namespace blimp {
+
+using BlobId = std::string;
+using BlobData = scoped_refptr<base::RefCountedData<const std::string>>;
+
+// An interface for a cache of blobs.
+class BLIMP_COMMON_EXPORT BlobCache {
+ public:
+  virtual ~BlobCache() {}
+
+  // Returns true if there is a cache item |id|.
+  virtual bool Contains(const BlobId& id) const = 0;
+
+  // Stores |data| with the identifier |id| in the cache.
+  // Command is ignored if there is already a cache item stored under |id|.
+  virtual void Put(const BlobId& id, BlobData data) = 0;
+
+  // Returns a pointer to the cache item |id|, or nullptr if no cache item
+  // exists under that identifier.
+  virtual BlobData Get(const BlobId& id) const = 0;
+};
+
+}  // namespace blimp
+
+#endif  // BLIMP_COMMON_BLOB_CACHE_BLOB_CACHE_H_