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diff --git a/tensorflow/core/framework/reader_interface.h b/tensorflow/core/framework/reader_interface.h
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+#ifndef TENSORFLOW_FRAMEWORK_READER_INTERFACE_H_
+#define TENSORFLOW_FRAMEWORK_READER_INTERFACE_H_
+
+#include <memory>
+#include <string>
+#include <vector>
+#include "tensorflow/core/framework/op_kernel.h"
+#include "tensorflow/core/framework/resource_mgr.h"
+#include "tensorflow/core/platform/port.h"
+#include "tensorflow/core/public/status.h"
+#include "tensorflow/core/public/tensor.h"
+
+namespace tensorflow {
+
+class QueueInterface;
+class ReaderInterface;
+
+// Readers are the mechanism for reading records from files in
+// TensorFlow graphs.  Each supported file format has a corresponding
+// ReaderInterface descendant and a corresponding Op & OpKernel
+// (implemented using ReaderOpKernel from reader_op_kernel.h).
+//
+// To use a Reader, you first encode "work" (some string, typically a
+// filename) in the Reader's "work queue".  It then processes the
+// "work" (reading records from the file), to produce key/value
+// strings.  The methods of this class are called by ReaderFoo ops,
+// so see ../ops/io_ops.cc for detailed descriptions.
+//
+// All descendants of this class must be thread-safe.
+//
+// See the design document here:
+// https://docs.google.com/document/d/1UAgZOoeehYr20TdzW2CoZ30V-aqQphU4SwKXsW7eJv4/edit#
+
+// TODO(josh11b): Switch this to Async.
+class ReaderInterface : public ResourceBase {
+ public:
+  // Read a single record into *key / *value.  May get more work from
+  // *queue if the current work is complete.  Sets the status on
+  // *context with an OutOfRange Status if the the current work is
+  // complete and the queue is done (closed and empty).
+  // This method may block.
+  virtual void Read(QueueInterface* queue, string* key, string* value,
+                    OpKernelContext* context) = 0;
+
+  // Restore this reader to its newly-constructed state.
+  virtual Status Reset() = 0;
+
+  // Accessors
+  virtual int64 NumRecordsProduced() = 0;
+  virtual int64 NumWorkUnitsCompleted() = 0;
+
+  // -- Serialization/Restoration support --
+  // Not all readers will support saving and restoring state.
+  virtual Status SerializeState(string* state) = 0;
+  // Note: Must Reset on error.
+  virtual Status RestoreState(const string& state) = 0;
+
+  string DebugString() override { return "a reader"; }
+
+ protected:
+  virtual ~ReaderInterface() {}
+};
+
+}  // namespace tensorflow
+
+#endif  // TENSORFLOW_FRAMEWORK_READER_INTERFACE_H_