syntax = "proto3";

package messaging_pb;

option go_package = "github.com/seaweedfs/seaweedfs/weed/pb/mq_pb";
option java_package = "seaweedfs.mq";
option java_outer_classname = "MessageQueueProto";

//////////////////////////////////////////////////

service SeaweedMessaging {

    // control plane
    rpc FindBrokerLeader (FindBrokerLeaderRequest) returns (FindBrokerLeaderResponse) {
    }

    // control plane for balancer
    rpc PublisherToPubBalancer (stream PublisherToPubBalancerRequest) returns (stream PublisherToPubBalancerResponse) {
    }
    rpc BalanceTopics (BalanceTopicsRequest) returns (BalanceTopicsResponse) {
    }

    // control plane for topic partitions
    rpc ListTopics (ListTopicsRequest) returns (ListTopicsResponse) {
    }
    rpc ConfigureTopic (ConfigureTopicRequest) returns (ConfigureTopicResponse) {
    }
    rpc LookupTopicBrokers (LookupTopicBrokersRequest) returns (LookupTopicBrokersResponse) {
    }

    // invoked by the balancer, running on each broker
    rpc AssignTopicPartitions (AssignTopicPartitionsRequest) returns (AssignTopicPartitionsResponse) {
    }
    rpc ClosePublishers(ClosePublishersRequest) returns (ClosePublishersResponse) {
    }
    rpc CloseSubscribers(CloseSubscribersRequest) returns (CloseSubscribersResponse) {
    }

    // subscriber connects to broker balancer, which coordinates with the subscribers
    rpc SubscriberToSubCoordinator (stream SubscriberToSubCoordinatorRequest) returns (stream SubscriberToSubCoordinatorResponse) {
    }

    // data plane for each topic partition
    rpc Publish (stream PublishRequest) returns (stream PublishResponse) {
    }
    rpc Subscribe (SubscribeRequest) returns (stream SubscribeResponse) {
    }
}

//////////////////////////////////////////////////

message FindBrokerLeaderRequest {
    string filer_group = 1;
}

message FindBrokerLeaderResponse {
    string broker = 1;
}

message Topic {
    string namespace = 1;
    string name = 2;
}
message Partition {
    int32 ring_size = 1;
    int32 range_start = 2;
    int32 range_stop = 3;
    int64 unix_time_ns = 4;
}

message Offset {
    Topic topic = 1;
    repeated PartitionOffset partition_offsets = 2;
}

message PartitionOffset {
    Partition partition = 1;
    int64 ts_ns = 2;
}

//////////////////////////////////////////////////
message BrokerStats {
    int32 cpu_usage_percent = 1;
    map<string, TopicPartitionStats> stats = 2;
}
message TopicPartitionStats {
    Topic topic = 1;
    Partition partition = 2;
    int32 consumer_count = 3;
    bool is_leader = 4;
}


message PublisherToPubBalancerRequest {
    message InitMessage {
        string broker = 1;
    }
    oneof message {
        InitMessage init = 1;
        BrokerStats stats = 2;
    }
}
message PublisherToPubBalancerResponse {
}

message BalanceTopicsRequest {
}
message BalanceTopicsResponse {
}

//////////////////////////////////////////////////
message ConfigureTopicRequest {
    Topic topic = 1;
    int32 partition_count = 2;
}
message ConfigureTopicResponse {
    repeated BrokerPartitionAssignment broker_partition_assignments = 2;
}
message ListTopicsRequest {
}
message ListTopicsResponse {
    repeated Topic topics = 1;
}
message LookupTopicBrokersRequest {
    Topic topic = 1;
    bool is_for_publish = 2;
}
message LookupTopicBrokersResponse {
    Topic topic = 1;
    repeated BrokerPartitionAssignment broker_partition_assignments = 2;
}
message BrokerPartitionAssignment {
    Partition partition = 1;
    string leader_broker = 2;
    repeated string follower_brokers = 3;
}

message AssignTopicPartitionsRequest {
    Topic topic = 1;
    repeated BrokerPartitionAssignment broker_partition_assignments = 2;
    bool is_leader = 3;
    bool is_draining = 4;
}
message AssignTopicPartitionsResponse {
}

message SubscriberToSubCoordinatorRequest {
    message InitMessage {
        string consumer_group = 1;
        string consumer_group_instance_id = 2;
        Topic topic = 3;
    }
    message AckMessage {
        Partition partition = 1;
        int64 ts_ns = 2;
    }
    oneof message {
        InitMessage init = 1;
        AckMessage ack = 2;
    }
}
message SubscriberToSubCoordinatorResponse {
    message AssignedPartition {
        Partition partition = 1;
        int64 ts_ns = 2;
        string broker = 3;
    }
    message Assignment {
        int64 generation = 1;
        repeated AssignedPartition assigned_partitions = 2;
    }
    oneof message {
        Assignment assignment = 1;
    }
}

//////////////////////////////////////////////////
message DataMessage {
    bytes key = 1;
    bytes value = 2;
    int64 ts_ns = 3;
}
message PublishRequest {
    message InitMessage {
        Topic topic = 1;
        Partition partition = 2;
        int32 ack_interval = 3;
    }
    oneof message {
        InitMessage init = 1;
        DataMessage data = 2;
    }
    int64 sequence = 3;
}
message PublishResponse {
    int64 ack_sequence = 1;
    string error = 2;
    bool should_close = 3;
}
message SubscribeRequest {
    message InitMessage {
        string consumer_group = 1;
        string consumer_id = 2;
        string client_id = 3;
        Topic topic = 4;
        Partition partition = 5;
        oneof offset {
            int64 start_offset = 6;
            int64 start_timestamp_ns = 7;
        }
        string filter = 8;
    }
    message AckMessage {
        int64 sequence = 1;
    }
    oneof message {
        InitMessage init = 1;
        AckMessage ack = 2;
    }
}
message SubscribeResponse {
    message CtrlMessage {
        string error = 1;
        bool is_end_of_stream = 2;
        bool is_end_of_topic = 3;
    }
    oneof message {
        CtrlMessage ctrl = 1;
        DataMessage data = 2;
    }
}
message ClosePublishersRequest {
    Topic topic = 1;
    int64 unix_time_ns = 2;
}
message ClosePublishersResponse {
}
message CloseSubscribersRequest {
    Topic topic = 1;
    int64 unix_time_ns = 2;
}
message CloseSubscribersResponse {
}