meta_storagepb.proto

syntax = "proto3";
package meta_storagepb;

import "gogoproto/gogo.proto";
import "rustproto.proto";

option (gogoproto.sizer_all) = true;
option (gogoproto.marshaler_all) = true;
option (gogoproto.unmarshaler_all) = true;
option (rustproto.lite_runtime_all) = true;

option java_package = "org.tikv.kvproto";

// MetaStorage is the meta storage service.
service MetaStorage {
    rpc Watch(WatchRequest) returns (stream WatchResponse) {}

    // Get is the same as etcd Range which might be implemented in a more common way
    // so that we can use other storages to replace etcd in the future.
    rpc Get(GetRequest) returns (GetResponse) {}

    rpc Put(PutRequest) returns (PutResponse) {}
}

enum ErrorType {
    OK = 0;
    UNKNOWN = 1;
    // required watch revision is smaller than current compact/min revision.
    DATA_COMPACTED = 2;
}

message Error {
    ErrorType type = 1;
    string message = 2;
}

message RequestHeader {
    // cluster_id is the ID of the cluster which be sent to.
    uint64 cluster_id = 1;
    // source is the source of the request.
    string source = 2;
}

message ResponseHeader {
    // cluster_id is the ID of the cluster which sent the response.
    uint64 cluster_id = 1;
    Error error = 2;
    int64 revision = 3;
}

// copied part of https://github.com/etcd-io/etcd/blob/7dfd29b0cc7ce25337276dce646ca2a65aa44b4d/api/etcdserverpb/rpc.proto
message WatchRequest {
    RequestHeader header = 1;
    bytes key = 2;
    bytes range_end = 3;
    int64 start_revision = 4;
    bool prev_kv = 5;
}

// copied part of https://github.com/etcd-io/etcd/blob/7dfd29b0cc7ce25337276dce646ca2a65aa44b4d/api/etcdserverpb/rpc.proto
message WatchResponse {
    ResponseHeader header = 1;
    int64 compact_revision = 2;
    repeated Event events = 3;
}

// copied part of https://github.com/etcd-io/etcd/blob/7dfd29b0cc7ce25337276dce646ca2a65aa44b4d/api/etcdserverpb/rpc.proto
message GetRequest {
    RequestHeader header = 1;
    bytes key = 2;
    bytes range_end = 3;
    int64 limit = 4;
    int64 revision = 5;
}

// copied part of https://github.com/etcd-io/etcd/blob/7dfd29b0cc7ce25337276dce646ca2a65aa44b4d/api/etcdserverpb/rpc.proto
message GetResponse {
    ResponseHeader header = 1;
    repeated KeyValue kvs = 2;
    bool more = 3;
    int64 count = 4;
}

// copied part of https://github.com/etcd-io/etcd/blob/7dfd29b0cc7ce25337276dce646ca2a65aa44b4d/api/etcdserverpb/rpc.proto
message PutRequest {
    RequestHeader header = 1;
    bytes key = 2;
    bytes value = 3;
    int64 lease = 4;
    bool prev_kv = 5;
}

// copied part of https://github.com/etcd-io/etcd/blob/7dfd29b0cc7ce25337276dce646ca2a65aa44b4d/api/etcdserverpb/rpc.proto
message PutResponse {
    ResponseHeader header = 1;
    KeyValue prev_kv = 2;
}

// copied from etcd https://github.com/etcd-io/etcd/blob/7dfd29b0cc7ce25337276dce646ca2a65aa44b4d/api/mvccpb/kv.proto
message KeyValue {
  // key is the key in bytes. An empty key is not allowed.
  bytes key = 1;
  // create_revision is the revision of last creation on this key.
  int64 create_revision = 2;
  // mod_revision is the revision of last modification on this key.
  int64 mod_revision = 3;
  // version is the version of the key. A deletion resets
  // the version to zero and any modification of the key
  // increases its version.
  int64 version = 4;
  // value is the value held by the key, in bytes.
  bytes value = 5;
  // lease is the ID of the lease that attached to key.
  // When the attached lease expires, the key will be deleted.
  // If lease is 0, then no lease is attached to the key.
  int64 lease = 6;
}

// copied from etcd https://github.com/etcd-io/etcd/blob/7dfd29b0cc7ce25337276dce646ca2a65aa44b4d/api/mvccpb/kv.proto
message Event {
  enum EventType {
    PUT = 0;
    DELETE = 1;
  }
  // type is the kind of event. If type is a PUT, it indicates
  // new data has been stored to the key. If type is a DELETE,
  // it indicates the key was deleted.
  EventType type = 1;
  // kv holds the KeyValue for the event.
  // A PUT event contains current kv pair.
  // A PUT event with kv.Version=1 indicates the creation of a key.
  // A DELETE/EXPIRE event contains the deleted key with
  // its modification revision set to the revision of deletion.
  KeyValue kv = 2;

  // prev_kv holds the key-value pair before the event happens.
  KeyValue prev_kv = 3;
}