src/core/lib/channel/compress_filter.h

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#ifndef GRPC_CORE_LIB_CHANNEL_COMPRESS_FILTER_H
#define GRPC_CORE_LIB_CHANNEL_COMPRESS_FILTER_H

#include "src/core/channel/channel_stack.h"

#define GRPC_COMPRESS_REQUEST_ALGORITHM_KEY "grpc-internal-encoding-request"

/** Compression filter for outgoing data.
 *
 * See <grpc/compression.h> for the available compression settings.
 *
 * Compression settings may come from:
 *  - Channel configuration, as established at channel creation time.
 *  - The metadata accompanying the outgoing data to be compressed. This is
 *    taken as a request only. We may choose not to honor it. The metadata key
 *    is given by \a GRPC_COMPRESS_REQUEST_ALGORITHM_KEY.
 *
 * Compression can be disabled for concrete messages (for instance in order to
 * prevent CRIME/BEAST type attacks) by having the GRPC_WRITE_NO_COMPRESS set in
 * the BEGIN_MESSAGE flags.
 *
 * The attempted compression mechanism is added to the resulting initial
 * metadata under the'grpc-encoding' key.
 *
 * If compression is actually performed, BEGIN_MESSAGE's flag is modified to
 * incorporate GRPC_WRITE_INTERNAL_COMPRESS. Otherwise, and regardless of the
 * aforementioned 'grpc-encoding' metadata value, data will pass through
 * uncompressed. */

extern const grpc_channel_filter grpc_compress_filter;

#endif /* GRPC_CORE_LIB_CHANNEL_COMPRESS_FILTER_H */