message FeedMetadata {
enum ProcessingInstruction {
// Do not use.
PROCESS_UNKNOWN = 0;
// This Feed message is one shard of a complete feed. Anything previously
// supplied by this partner will be deleted; the contents of this feed
// represent the entire state of the world.
PROCESS_AS_COMPLETE = 1;
// Do not use. This value is deprecated.
// Feed message is one shard of an incremental feed.
// Existing entities will be left untouched except as modified in this feed.
PROCESS_AS_INCREMENTAL = 2;
}
// Instructs us how to process the feed: either as a shard of a complete feed,
// or as a shard of an incremental update. (required)
ProcessingInstruction processing_instruction = 1;
// The current shard and total number of shards for this feed.
//
// Shard number is assumed to be zero-based.
//
// There does not need to be any relationship to the file name.
//
// Shards do not need to be transferred in order, and they may not be
// processed in order. (both required)
int32 shard_number = 2;
int32 total_shards = 3;
// An identifier that must be consistent across all shards in a feed.
// This value must be globally unique across each feed type.
//
// This value ensures that complete feeds spanning multiple shards are
// processed together correctly.
//
// Clients only need to set this value when the processing_instruction is set
// to PROCESS_AS_COMPLETE and the feed spans multiple shards (defined by
// total_shards).
//
// Feeds that span multiple shards must set this nonce to the same value.
// (required if total shards > 1)
uint64 nonce = 5;
// The timestamp at which this feed shard was generated.
//
// In Unix time format (seconds since the epoch). (required)
int64 generation_timestamp = 4;
}
