syntax = "proto3";
package pdpb;

import "metapb.proto";
import "eraftpb.proto";

import "gogoproto/gogo.proto";

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

option java_package = "com.pingcap.tikv.kvproto";

service PD {
    // GetMembers get the member list of this cluster. It does not require
    // the cluster_id in request matchs the id of this cluster.
    rpc GetMembers(GetMembersRequest) returns (GetMembersResponse) {}

    rpc Tso(stream TsoRequest) returns (stream TsoResponse) {}

    rpc Bootstrap(BootstrapRequest) returns (BootstrapResponse) {}

    rpc IsBootstrapped(IsBootstrappedRequest) returns (IsBootstrappedResponse) {}

    rpc AllocID(AllocIDRequest) returns (AllocIDResponse) {}

    rpc GetStore(GetStoreRequest) returns (GetStoreResponse) {}

    rpc PutStore(PutStoreRequest) returns (PutStoreResponse) {}

    rpc GetAllStores(GetAllStoresRequest) returns (GetAllStoresResponse) {}

    rpc StoreHeartbeat(StoreHeartbeatRequest) returns (StoreHeartbeatResponse) {}

    rpc RegionHeartbeat(stream RegionHeartbeatRequest) returns (stream RegionHeartbeatResponse) {}

    rpc GetRegion(GetRegionRequest) returns (GetRegionResponse) {}

    rpc GetPrevRegion(GetRegionRequest) returns (GetRegionResponse) {}

    rpc GetRegionByID(GetRegionByIDRequest) returns (GetRegionResponse) {}

    rpc AskSplit(AskSplitRequest) returns (AskSplitResponse) {
        // Use AskBatchSplit instead.
        option deprecated = true;
    }

    rpc ReportSplit(ReportSplitRequest) returns (ReportSplitResponse) {
        // Use ResportBatchSplit instead.
        option deprecated = true;
    }

    rpc AskBatchSplit(AskBatchSplitRequest) returns (AskBatchSplitResponse) {}

    rpc ReportBatchSplit(ReportBatchSplitRequest) returns (ReportBatchSplitResponse) {}

    rpc GetClusterConfig(GetClusterConfigRequest) returns (GetClusterConfigResponse) {}

    rpc PutClusterConfig(PutClusterConfigRequest) returns (PutClusterConfigResponse) {}

    rpc ScatterRegion(ScatterRegionRequest) returns (ScatterRegionResponse) {}

    rpc GetGCSafePoint(GetGCSafePointRequest) returns (GetGCSafePointResponse) {}

    rpc UpdateGCSafePoint(UpdateGCSafePointRequest) returns (UpdateGCSafePointResponse) {}
}

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

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

enum ErrorType {
    OK = 0;
    UNKNOWN = 1;
    NOT_BOOTSTRAPPED = 2;
    STORE_TOMBSTONE = 3;
    ALREADY_BOOTSTRAPPED = 4;
    INCOMPATIBLE_VERSION = 5;
}

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

message TsoRequest {
    RequestHeader header = 1;

    uint32 count = 2;
}

message Timestamp {
    int64 physical = 1;
    int64 logical = 2;
}

message TsoResponse {
    ResponseHeader header = 1;

    uint32 count = 2;
    Timestamp timestamp = 3;
}

message BootstrapRequest {
    RequestHeader header = 1;

    metapb.Store store = 2;
    metapb.Region region = 3;
}

message BootstrapResponse {
    ResponseHeader header = 1;
}

message IsBootstrappedRequest {
    RequestHeader header = 1;
}

message IsBootstrappedResponse {
    ResponseHeader header = 1;

    bool bootstrapped = 2;
}

message AllocIDRequest {
    RequestHeader header = 1;
}

message AllocIDResponse {
    ResponseHeader header = 1;

    uint64 id = 2;
}

message GetStoreRequest {
    RequestHeader header = 1;

    uint64 store_id = 2;
}

message GetStoreResponse {
    ResponseHeader header = 1;

    metapb.Store store = 2;
}

message PutStoreRequest {
    RequestHeader header = 1;

    metapb.Store store = 2;
}

message PutStoreResponse {
    ResponseHeader header = 1;
}

message GetAllStoresRequest {
    RequestHeader header = 1;
}

message GetAllStoresResponse {
    ResponseHeader header = 1;

    repeated metapb.Store stores = 2;
}

message GetRegionRequest {
    RequestHeader header = 1;

    bytes region_key = 2;
}

message GetRegionResponse {
    ResponseHeader header = 1;

    metapb.Region region = 2;
    metapb.Peer leader = 3;
}

message GetRegionByIDRequest {
    RequestHeader header = 1;

    uint64 region_id = 2;
}

// Use GetRegionResponse as the response of GetRegionByIDRequest.

message GetClusterConfigRequest {
    RequestHeader header = 1;
}

message GetClusterConfigResponse {
    ResponseHeader header = 1;

    metapb.Cluster cluster = 2;
}

message PutClusterConfigRequest {
    RequestHeader header = 1;

    metapb.Cluster cluster = 2;
}

message PutClusterConfigResponse {
    ResponseHeader header = 1;
}

message Member {
    // name is the name of the PD member.
    string name = 1;
    // member_id is the unique id of the PD member.
    uint64 member_id = 2;
    repeated string peer_urls = 3;
    repeated string client_urls = 4;
    int32 leader_priority = 5;
}

message GetMembersRequest {
    RequestHeader header = 1;
}

message GetMembersResponse {
    ResponseHeader header = 1;

    repeated Member members = 2;
    Member leader = 3;
    Member etcd_leader = 4;
}

message PeerStats {
    metapb.Peer peer = 1;
    uint64 down_seconds = 2;
}

message RegionHeartbeatRequest {
    RequestHeader header = 1;

    metapb.Region region = 2;
    // Leader Peer sending the heartbeat.
    metapb.Peer leader = 3;
    // Leader considers that these peers are down.
    repeated PeerStats down_peers = 4;
    // Pending peers are the peers that the leader can't consider as
    // working followers.
    repeated metapb.Peer pending_peers = 5;
    // Bytes read/written during this period.
    uint64 bytes_written = 6;
    uint64 bytes_read = 7;
    // Keys read/written during this period.
    uint64 keys_written = 8;
    uint64 keys_read = 9;
    // Approximate region size.
    uint64 approximate_size = 10;
    reserved 11;
    // Actually reported time interval
    TimeInterval interval = 12;
    // Approximate number of keys.
    uint64 approximate_keys = 13;
}

message ChangePeer {
    metapb.Peer peer = 1;
    eraftpb.ConfChangeType change_type = 2;
}

message TransferLeader {
    metapb.Peer peer = 1;
}

message Merge {
    metapb.Region target = 1;
}

message SplitRegion {
    CheckPolicy policy = 1;
}

enum CheckPolicy {
    SCAN = 0;
    APPROXIMATE = 1;
}

message RegionHeartbeatResponse {
    ResponseHeader header = 1;

    // Notice, Pd only allows handling reported epoch >= current pd's.
    // Leader peer reports region status with RegionHeartbeatRequest
    // to pd regularly, pd will determine whether this region
    // should do ChangePeer or not.
    // E,g, max peer number is 3, region A, first only peer 1 in A.
    // 1. Pd region state -> Peers (1), ConfVer (1).
    // 2. Leader peer 1 reports region state to pd, pd finds the
    // peer number is < 3, so first changes its current region
    // state -> Peers (1, 2), ConfVer (1), and returns ChangePeer Adding 2.
    // 3. Leader does ChangePeer, then reports Peers (1, 2), ConfVer (2),
    // pd updates its state -> Peers (1, 2), ConfVer (2).
    // 4. Leader may report old Peers (1), ConfVer (1) to pd before ConfChange
    // finished, pd stills responses ChangePeer Adding 2, of course, we must
    // guarantee the second ChangePeer can't be applied in TiKV.
    ChangePeer change_peer = 2;
    // Pd can return transfer_leader to let TiKV does leader transfer itself.
    TransferLeader transfer_leader = 3;
    // ID of the region
    uint64 region_id = 4;
    metapb.RegionEpoch region_epoch = 5;
    // Leader of the region at the moment of the corresponding request was made.
    metapb.Peer target_peer = 6;
    Merge merge = 7;
    // PD sends split_region to let TiKV split a region into two regions.
    SplitRegion split_region = 8;
}

message AskSplitRequest {
    RequestHeader header = 1;

    metapb.Region region = 2;
}

message AskSplitResponse {
    ResponseHeader header = 1;

    // We split the region into two, first uses the origin
    // parent region id, and the second uses the new_region_id.
    // We must guarantee that the new_region_id is global unique.
    uint64 new_region_id = 2;
    // The peer ids for the new split region.
    repeated uint64 new_peer_ids = 3;
}

message ReportSplitRequest {
    RequestHeader header = 1;

    metapb.Region left = 2;
    metapb.Region right = 3;
}

message ReportSplitResponse {
    ResponseHeader header = 1;
}

message AskBatchSplitRequest {
    RequestHeader header = 1;

    metapb.Region region = 2;
    uint32 split_count = 3;
}

message SplitID {
    uint64 new_region_id = 1;
    repeated uint64 new_peer_ids = 2;
}

message AskBatchSplitResponse {
    ResponseHeader header = 1;

    repeated SplitID ids = 2;
}

message ReportBatchSplitRequest {
    RequestHeader header = 1;

    repeated metapb.Region regions = 2;
}

message ReportBatchSplitResponse {
    ResponseHeader header = 1;
}

message TimeInterval {
    // The unix timestamp in seconds of the start of this period.
    uint64 start_timestamp = 1;
    // The unix timestamp in seconds of the end of this period.
    uint64 end_timestamp = 2;
}

message StoreStats {
    uint64 store_id = 1;
    // Capacity for the store.
    uint64 capacity = 2;
    // Available size for the store.
    uint64 available = 3;
    // Total region count in this store.
    uint32 region_count = 4;
    // Current sending snapshot count.
    uint32 sending_snap_count = 5;
    // Current receiving snapshot count.
    uint32 receiving_snap_count = 6;
    // When the store is started (unix timestamp in seconds).
    uint32 start_time = 7;
    // How many region is applying snapshot.
    uint32 applying_snap_count = 8;
    // If the store is busy
    bool is_busy = 9;
    // Actually used space by db
    uint64 used_size = 10;
    // Bytes written for the store during this period.
    uint64 bytes_written = 11;
    // Keys written for the store during this period.
    uint64 keys_written = 12;
    // Bytes read for the store during this period.
    uint64 bytes_read = 13;
    // Keys read for the store during this period.
    uint64 keys_read = 14;
    // Actually reported time interval
    TimeInterval interval = 15;
}

message StoreHeartbeatRequest {
    RequestHeader header = 1;

    StoreStats stats = 2;
}

message StoreHeartbeatResponse {
    ResponseHeader header = 1;
}

message ScatterRegionRequest {
    RequestHeader header = 1;

    uint64 region_id = 2;

    // PD will use these region information if it can't find the region.
    // For example, the region is just split and hasn't report to PD yet.
    metapb.Region region = 3;
    metapb.Peer   leader = 4;
}

message ScatterRegionResponse {
    ResponseHeader header = 1;
}

message GetGCSafePointRequest {
    RequestHeader header = 1;
}

message GetGCSafePointResponse {
    ResponseHeader header = 1;

    uint64 safe_point = 2;
}

message UpdateGCSafePointRequest {
    RequestHeader header = 1;

    uint64 safe_point = 2;
}

message UpdateGCSafePointResponse {
    ResponseHeader header = 1;

    uint64 new_safe_point = 2;
}