drafts for public grpc api final revision

fix some more issues

fix more issues

ref:ea53351742bcd9d93d43d7e895bf1eca9a2b412e

2 files changed, 280 insertions, 276 deletions

diff --git a/ydb/public/api/grpc/draft/ydb_topic_v1.proto b/ydb/public/api/grpc/draft/ydb_topic_v1.proto
index d3bb31046a..23219ef6ef 100644
--- a/ydb/public/api/grpc/draft/ydb_topic_v1.proto
+++ b/ydb/public/api/grpc/draft/ydb_topic_v1.proto
@@ -27,7 +27,7 @@ service TopicService {
     //        <----------------
     //         [something went wrong] (status != SUCCESS, issues not empty)
     //        <----------------
-    rpc StreamWrite(stream StreamWriteClientMessage) returns (stream StreamWriteServerMessage);
+    rpc StreamWrite(stream StreamWriteMessage.FromClient) returns (stream StreamWriteMessage.FromServer);
 
 
     // Create Read Session
@@ -61,7 +61,7 @@ service TopicService {
     //        <----------------
     //         [something went wrong] (status != SUCCESS, issues not empty)
     //        <----------------
-    rpc StreamRead(stream StreamReadClientMessage) returns (stream StreamReadServerMessage);
+    rpc StreamRead(stream StreamReadMessage.FromClient) returns (stream StreamReadMessage.FromServer);
 
 
     // Describe topic command.
@@ -84,6 +84,6 @@ service TopicService {
     rpc AddConsumer(AddConsumerRequest) returns (AddConsumerResponse);
 
 
-    // Remove consumer command.
-    rpc RemoveConsumer(RemoveConsumerRequest) returns (RemoveConsumerResponse);
+    // Drop consumer command.
+    rpc DropConsumer(RemoveConsumerRequest) returns (RemoveConsumerResponse);
 }
diff --git a/ydb/public/api/protos/ydb_topic.proto b/ydb/public/api/protos/ydb_topic.proto
index bb73c62931..1ea75514ef 100644
--- a/ydb/public/api/protos/ydb_topic.proto
+++ b/ydb/public/api/protos/ydb_topic.proto
@@ -5,6 +5,7 @@ import "ydb/public/api/protos/ydb_status_codes.proto";
 import "ydb/public/api/protos/ydb_issue_message.proto";
 import "ydb/public/api/protos/annotations/validation.proto";
 
+import "google/protobuf/duration.proto";
 import "google/protobuf/timestamp.proto";
 
 package Ydb.Topic;
@@ -19,6 +20,7 @@ enum Codec {
     CODEC_GZIP = 2;
     CODEC_LZOP = 3;
     CODEC_ZSTD = 4;
+    CODEC_CUSTOM = 10000;
 }
 
 // Represents range [start, end).
@@ -37,23 +39,42 @@ message UpdateTokenRequest {
 message UpdateTokenResponse {
 }
 
-// Request for write session. Contains one of:
-//     InitRequest - handshake request.
-//     WriteRequest - portion of data to be written.
-//     UpdateTokenRequest - user credentials if update is needed.
-message StreamWriteClientMessage {
-    oneof client_message {
-        InitRequest init_request = 1;
-        WriteRequest write_request = 2;
-        UpdateTokenRequest update_token_request = 3;
+// Messages for bidirectional streaming rpc StreamWrite
+message StreamWriteMessage {
+    // Client-server message for write session. Contains one of:
+    //     InitRequest - handshake request.
+    //     WriteRequest - portion of data to be written.
+    //     UpdateTokenRequest - user credentials if update is needed.
+    message FromClient {
+        oneof client_message {
+            InitRequest init_request = 1;
+            WriteRequest write_request = 2;
+            UpdateTokenRequest update_token_request = 3;
+        }
+    }
+
+    // Server-client message for write session. Contains either non-success status, or one of:
+    //     InitResponse - correct handshake response.
+    //     WriteResponse - acknowledgment of storing client messages.
+    //     UpdateTokenResponse - acknowledgment of reauthentication and reauthorization.
+    message FromServer {
+        // Server status of response.
+        Ydb.StatusIds.StatusCode status = 1;
+
+        // Issues if any.
+        repeated Ydb.Issue.IssueMessage issues = 2;
+
+        oneof server_message {
+            InitResponse init_response = 3;
+            WriteResponse write_response = 4;
+            UpdateTokenResponse update_token_response = 5;
+        }
     }
 
     // Handshake request that must be sent to server first.
     message InitRequest {
         // Full path of topic to write to.
-        // e.g. /database_path/dir/my-topic
-        // or /database_path/dir/my-topic.federation-mirrors/sas
-        string topic = 1;
+        string path = 1;
         // Message group identifier of client data stream.
         string message_group_id = 2;
         // User metadata attached to this write session.
@@ -67,6 +88,21 @@ message StreamWriteClientMessage {
         }
     }
 
+    // Response for handshake.
+    message InitResponse {
+        // Last persisted message's sequence number for this message group.
+        // Zero for new message group.
+        int64 last_seq_no = 1;
+        // Unique identifier of write session. Used for debug purposes.
+        string session_id = 2;
+        // Identifier of partition that is matched for this write session.
+        int64 partition_id = 3;
+
+        // Client can only use compression codecs from this set to write messages to topic, session will be closed with BAD_REQUEST otherwise.
+        // See enum Codec above for values.
+        repeated int64 supported_codecs = 10;
+    }
+
     // Represents portion of client messages.
     message WriteRequest {
         repeated MessageData messages = 1;
@@ -87,39 +123,6 @@ message StreamWriteClientMessage {
             int64 uncompressed_size = 4;
         }
     }
-}
-
-// Response for write session. Contains either non-success status, or one of:
-//     InitResponse - correct handshake response.
-//     WriteResponse - acknowledgment of storing client messages.
-//     UpdateTokenResponse - acknowledgment of reauthentication and reauthorization.
-message StreamWriteServerMessage {
-    // Server status of response.
-    Ydb.StatusIds.StatusCode status = 1;
-
-    // Issues if any.
-    repeated Ydb.Issue.IssueMessage issues = 2;
-
-    oneof server_message {
-        InitResponse init_response = 3;
-        WriteResponse write_response = 4;
-        UpdateTokenResponse update_token_response = 5;
-    }
-
-    // Response for handshake.
-    message InitResponse {
-        // Last persisted message's sequence number for this message group.
-        // Zero for new message group.
-        int64 last_seq_no = 1;
-        // Unique identifier of write session. Used for debug purposes.
-        string session_id = 2;
-        // Identifier of partition that is matched for this write session.
-        int64 partition_id = 3;
-
-        // Client can only use compression codecs from this set to write messages to topic, session will be closed with BAD_REQUEST otherwise.
-        // See enum Codec above for values.
-        repeated int64 supported_codecs = 10;
-    }
 
     // Message that represents acknowledgment for sequence of client messages.
     // This sequence is persisted together so write statistics is for messages batch.
@@ -164,37 +167,86 @@ message StreamWriteServerMessage {
         // Message with write statistics.
         message WriteStatistics {
             // Time spent in persisting of data. Same for each message in response.
-            google.protobuf.Duration persist = 1;
+            google.protobuf.Duration persisting_time = 1;
             // Time spent in queue before persisting, minimal of all messages in response.
-            google.protobuf.Duration queued_in_partition_min = 2;
+            google.protobuf.Duration min_queue_wait_time = 2;
             // Time spent in queue before persisting, maximal of all messages in response.
-            google.protobuf.Duration queued_in_partition_max = 3;
+            google.protobuf.Duration max_queue_wait_time = 3;
             // Time spent awaiting for partition write quota. Same for each message in response.
-            google.protobuf.Duration throttled_on_partition = 4;
+            google.protobuf.Duration partition_quota_wait_time = 4;
             // Time spent awaiting for topic write quota. Same for each message in response.
-            google.protobuf.Duration throttled_on_topic = 5;
+            google.protobuf.Duration topic_quota_wait_time = 5;
         }
     }
 }
 
+// Within a StreamRead session delivered messages are separated by partition.
+// Reads from a single partition are represented by a partition session.
+message PartitionSession {
+    // Identitifier of partition session. Unique inside one RPC call.
+    int64 partition_session_id = 1;
+    // Topic path of partition.
+    string path = 2;
+    // Partition identifier.
+    int64 partition_id = 3;
+}
 
-// Request for read session. Contains one of:
-//     InitRequest - handshake request.
-//     ReadRequest - request for data.
-//     CommitOffsetRequest - request for commit of some read data.
-//     StartPartitionSessionResponse - signal for server that client is ready to get data from partition.
-//     StopPartitionSessionResponse - signal for server that client finished working with partition. Must be sent only after corresponding request from server.
-//     PartitionSessionStatusRequest - request for session status
-//     UpdateTokenRequest - request to update auth token
-message StreamReadClientMessage {
-    oneof client_message {
-        InitRequest init_request = 1;
-        ReadRequest read_request = 2;
-        StartPartitionSessionResponse start_partition_session_response = 3;
-        StopPartitionSessionResponse stop_partition_session_response = 4;
-        CommitOffsetRequest commit_offset_request = 5;
-        PartitionSessionStatusRequest partition_session_status_request = 6;
-        UpdateTokenRequest update_token_request = 7;
+// Messages for bidirectional streaming rpc StreamingRead
+message StreamReadMessage {
+    // Client-server message for read session. Contains one of:
+    //     InitRequest - handshake request.
+    //     ReadRequest - request for data.
+    //     CommitOffsetRequest - request for commit of some read data.
+    //     PartitionSessionStatusRequest - request for session status
+    //     UpdateTokenRequest - request to update auth token
+    //
+    //     StartPartitionSessionResponse - Response to StreamReadServerMessage.StartPartitionSessionRequest.
+    //         Client signals it is ready to get data from partition.
+    //     StopPartitionSessionResponse - Response to StreamReadServerMessage.StopPartitionSessionRequest.
+    //         Client signals it has finished working with partition. Mandatory for graceful stop, optional otherwise.
+    message FromClient {
+        oneof client_message {
+            // Client requests.
+            InitRequest init_request = 1;
+            ReadRequest read_request = 2;
+            CommitOffsetRequest commit_offset_request = 3;
+            PartitionSessionStatusRequest partition_session_status_request = 4;
+            UpdateTokenRequest update_token_request = 5;
+
+            // Responses to respective server commands.
+            StartPartitionSessionResponse start_partition_session_response = 6;
+            StopPartitionSessionResponse stop_partition_session_response = 7;
+        }
+    }
+
+    // Server-client message for read session. Contains one of:
+    //     InitResponse - handshake response from server.
+    //     ReadResponse - portion of data.
+    //     CommitOffsetResponse - acknowledgment for commit.
+    //     PartitionSessionStatusResponse - server response with partition session status.
+    //     UpdateTokenResponse - acknowledgment of token update.
+    //
+    //     StartPartitionSessionRequest - command from server to create a partition session.
+    //     StopPartitionSessionRequest - command from server to destroy a partition session.
+    message FromServer {
+        // Server status of response.
+        Ydb.StatusIds.StatusCode status = 1;
+
+        // Issues if any.
+        repeated Ydb.Issue.IssueMessage issues = 2;
+
+        oneof server_message {
+            // Responses to respective client requests.
+            InitResponse init_response = 3;
+            ReadResponse read_response = 4;
+            CommitOffsetResponse commit_offset_response = 5;
+            PartitionSessionStatusResponse partition_session_status_response = 6;
+            UpdateTokenResponse update_token_response = 7;
+
+            // Server commands.
+            StartPartitionSessionRequest start_partition_session_request = 8;
+            StopPartitionSessionRequest stop_partition_session_request = 9;
+        }
     }
 
     // Handshake request.
@@ -215,150 +267,33 @@ message StreamReadClientMessage {
             // Zero means infinite lag.
             google.protobuf.Duration max_lag = 3;
             // Read data only after this timestamp from this topic.
-            google.protobuf.Timestamp start_from_written_at = 4;
-        }
-    }
-
-    // Message that represents client readiness for receiving more data.
-    message ReadRequest {
-        // Server and client each keep total bytes size of all ReadResponses.
-        // When client is ready to receive 'bytes_size' more bytes in responses, it signals it via this ReadRequest.
-        // client is ready to receive ReadResponses with total size up to bytes_size.
-        // Except the case when the first message in response exceeds it - then it will be delivered.
-        // The case when the first message in response exceeds available bytes_size sum, is an exception. Such message will be still delivered.
-        // Available sum become negative in this case
-        int64 bytes_size = 1;
-    }
-
-    // Signal for server that cient is ready to recive data for partition.
-    message StartPartitionSessionResponse {
-        // Partition session identifier of partition to start read.
-        int64 partition_session_id = 1;
-
-        // Reads in this partition session will start from offset no less than read_offset.
-        // If read_offset is set, server will check that read_offset is no less that actual committed offset.
-        // If check will fail then server will send a message describing error in status and issues fields, then close stream.
-        //
-        // If read_offset is not set, no check will be made.
-        // InitRequest.max_lag and InitRequest.start_from_written_at could lead to skip of more messages.
-        // Server will return data starting from offset that is maximum of actual committed offset, read_offset (if set)
-        // and offsets calculated from InitRequest.max_lag and InitRequest.start_from_written_at.
-        optional int64 read_offset = 2;
-        // All messages with offset less than commit_offset are processed by client. Server will commit this position if this is not done yet.
-        optional int64 commit_offset = 3;
-    }
-
-    // Signal for server that client finished working with this partition. Must be sent only after corresponding Release request from server.
-    // Server will give this partition to other read session only after Released signal.
-    message StopPartitionSessionResponse {
-        // Partition session identifier of partition session that is released by client.
-        int64 partition_session_id = 1;
-    }
-
-    // Signal for server that client processed some read data.
-    message CommitOffsetRequest {
-        // Partition offsets that indicates processed data.
-        repeated PartitionCommitOffset commit_offsets = 1;
-
-        // Message that is used for describing commit.
-        message PartitionCommitOffset {
-            // Identifier of partition session with data to commit.
-            int64 partition_session_id = 1;
-            // Processed offsets ranges, repeated in case of disjoint ranges.
-            repeated OffsetsRange offsets = 2;
+            google.protobuf.Timestamp read_from = 4;
         }
     }
 
-    message PartitionSessionStatusRequest {
-        int64 partition_session_id = 1;
-    }
-}
-
-// Within a StreamRead session delivered messages are separated by partition.
-// Reads from a single partition are represented by a partition session.
-message PartitionSession {
-    // Identitifier of partition session. Unique inside one RPC call.
-    int64 partition_session_id = 1;
-    // Topic path of partition.
-    string topic = 2;
-    // Partition identifier.
-    int64 partition_id = 3;
-}
-
-// Response for read session. Contains one of:
-//     InitResponse - handshake response from server.
-//     ReadResponse - portion of data.
-//     StartPartitionSessionRequest - command from server to create a partition session.
-//     StopPartitionSessionRequest - command from server to destroy a partition session.
-//     CommitOffsetResponse - acknowledgment for commit.
-//     PartitionSessionStatusResponse - server response with partition session status.
-//     UpdateTokenResponse - acknowledgment of token update.
-message StreamReadServerMessage {
-    // Server status of response.
-    Ydb.StatusIds.StatusCode status = 1;
-
-    // Issues if any.
-    repeated Ydb.Issue.IssueMessage issues = 2;
-
-    oneof server_message {
-        InitResponse init_response = 3;
-        ReadResponse read_response = 4;
-        StartPartitionSessionRequest start_partition_session_request = 5;
-        StopPartitionSessionRequest stop_partition_session_request = 6;
-        CommitOffsetResponse commit_offset_response = 7;
-        PartitionSessionStatusResponse partition_session_status_response = 8;
-        UpdateTokenResponse update_token_response = 9;
-    }
-
     // Handshake response.
     message InitResponse {
         // Read session identifier for debug purposes.
         string session_id = 1;
     }
 
-    // Command to create and start a partition session.
-    // Client must react on this signal by sending StartPartitionSessionResponse when ready to recieve data from this partition.
-    message StartPartitionSessionRequest {
-        // Partition session description.
-        PartitionSession partition_session = 1;
-
-        // Actual upper bound for all committed offsets.
-        // I.e. each offset up to and including (committed_offset - 1) was committed.
-        int64 committed_offset = 2;
-
-        // First and next-after-last offsets of messages in partition.
-        OffsetsRange partition_offsets = 3;
-    }
-
-    // Command to stop and destroy concrete partition session.
-    message StopPartitionSessionRequest {
-        // Identifier of partition session that is ready to be closed by server.
-        int64 partition_session_id = 1;
-
-        // Flag of graceful stop.
-        // If True then server is waiting for response from client before giving of this partition for other read session.
-        // Server will not send more data from this partition.
-        // Client can process all received data and wait for commit and only after send response.
-        // If False then server gives partition for other session right now.
-        // All further commits for this PartitionSession has no effect. Server is not waiting for response.
-        bool graceful = 2;
-
-        // Upper bound for committed offsets.
-        int64 committed_offset = 3;
-    }
-
-    // Acknowledgement for commits.
-    message CommitOffsetResponse {
-        // Partitions with progress.
-        repeated PartitionCommittedOffset partitions_committed_offsets = 1;
-
-        // Per-partition commit representation.
-        message PartitionCommittedOffset {
-            // Partition session identifier.
-            int64 partition_session_id = 1;
-            // Upper bound for committed offsets.
-            int64 committed_offset = 2;
-        }
+    // Message that represents client readiness for receiving more data.
+    message ReadRequest {
+        // Server and client each keep track of total bytes size of all ReadResponses.
+        // When client is ready to receive N more bytes in responses (to increment possible total by N), it sends a ReadRequest with bytes_size = N.
+        //
+        // Example:
+        // 1) Let client have 200 B buffer. It sends ReadRequest with bytes_size = 200;
+        // 2) Server returns ReadResponse with bytes_size = 150; now client buffer has 50 free bytes, server is free to send up to 50 bytes in responses.
+        // 3) Client processes 100 bytes from buffer, now buffer free space is 150 bytes. Client sends ReadRequest with bytes_size = 100;
+        // 4) Server is free to send up to 50 + 100 = 150 bytes. It may, for example,
+        //   send one 70 B response and another 80 B response without receiving additional requests.
+        //
+        // So in expression 'A = (sum of bytes_size in all ReadRequests) - (sum of bytes_size in all ReadResponses)'
+        //   server will keep A (available size for responses) non-negative.
+        // But there is an exception. If server receives ReadRequest, and the first message in response exceeds A -
+        // then it will still be delivered, and A will become negative until client sends enough additional ReadRequests.
+        int64 bytes_size = 1;
     }
 
     // Data read.
@@ -415,20 +350,109 @@ message StreamReadServerMessage {
         int64 bytes_size = 2;
     }
 
+    // Signal for server that client processed some read data.
+    message CommitOffsetRequest {
+        // Partition offsets that indicates processed data.
+        repeated PartitionCommitOffset commit_offsets = 1;
+
+        // Message that is used for describing commit.
+        message PartitionCommitOffset {
+            // Identifier of partition session with data to commit.
+            int64 partition_session_id = 1;
+            // Processed offsets ranges, repeated in case of disjoint ranges.
+            repeated OffsetsRange offsets = 2;
+        }
+    }
+
+    // Acknowledgement for commits.
+    message CommitOffsetResponse {
+        // Partitions with progress.
+        repeated PartitionCommittedOffset partitions_committed_offsets = 1;
+
+        // Per-partition commit representation.
+        message PartitionCommittedOffset {
+            // Partition session identifier.
+            int64 partition_session_id = 1;
+            // Upper bound for committed offsets.
+            int64 committed_offset = 2;
+        }
+    }
+
+    message PartitionSessionStatusRequest {
+        int64 partition_session_id = 1;
+    }
+
     // Response for status request.
     message PartitionSessionStatusResponse {
         // Identifier of partition session whose status was requested.
         int64 partition_session_id = 1;
 
-        // First and next-after-last offsets of messages in partition.
+        // Partition contains messages with offsets in range [start, end).
         OffsetsRange partition_offsets = 2;
 
         // Upper bound for committed offsets.
+        // TODO example (here or in CommitRequest)
         int64 committed_offset = 3;
 
         // Write timestamp of next message written to this partition will be no less than write_time_high_watermark.
         google.protobuf.Timestamp write_time_high_watermark = 4;
     }
+
+    // Command from server to create and start a partition session.
+    // Client must react on this command by sending StartPartitionSessionResponse when ready to recieve data from this partition.
+    message StartPartitionSessionRequest {
+        // Partition session description.
+        PartitionSession partition_session = 1;
+
+        // Actual upper bound for all committed offsets.
+        // I.e. each offset up to and including (committed_offset - 1) was committed.
+        int64 committed_offset = 2;
+
+        // Partition contains messages with offsets in range [start, end).
+        OffsetsRange partition_offsets = 3;
+    }
+
+    // Signal for server that cient is ready to recive data for partition.
+    message StartPartitionSessionResponse {
+        // Partition session identifier of partition to start read.
+        int64 partition_session_id = 1;
+
+        // Reads in this partition session will start from offset no less than read_offset.
+        // If read_offset is set, server will check that read_offset is no less that actual committed offset.
+        // If check will fail then server will send a message describing error in status and issues fields, then close stream.
+        //
+        // If read_offset is not set, no check will be made.
+        // InitRequest.max_lag and InitRequest.read_from could lead to skip of more messages.
+        // Server will return data starting from offset that is maximum of actual committed offset, read_offset (if set)
+        // and offsets calculated from InitRequest.max_lag and InitRequest.read_from.
+        optional int64 read_offset = 2;
+        // All messages with offset less than commit_offset are processed by client. Server will commit this position if this is not done yet.
+        optional int64 commit_offset = 3;
+    }
+
+    // Command from server to stop and destroy concrete partition session.
+    message StopPartitionSessionRequest {
+        // Identifier of partition session that is ready to be closed by server.
+        int64 partition_session_id = 1;
+
+        // Flag of graceful stop.
+        // If True then server is waiting for response from client before giving of this partition for other read session.
+        // Server will not send more data from this partition.
+        // Client can process all received data and wait for commit and only after send response.
+        // If False then server gives partition for other session right now.
+        // All further commits for this PartitionSession has no effect. Server is not waiting for response.
+        bool graceful = 2;
+
+        // Upper bound for committed offsets.
+        int64 committed_offset = 3;
+    }
+
+    // Signal for server that client finished working with this partition. Must be sent only after corresponding StopPartitionSessionRequest from server.
+    // Server will give this partition to other read session only after StopPartitionSessionResponse signal.
+    message StopPartitionSessionResponse {
+        // Partition session identifier of partition session that is released by client.
+        int64 partition_session_id = 1;
+    }
 }
 
 
@@ -452,70 +476,58 @@ message DropTopicResult {
 
 // Message for describing topic internals.
 message TopicSettings {
-    // How many partitions in topic. Must less than database limit. Default limit - 10.
-    int32 partitions_count = 1 [(value) = "> 0"];
-    oneof retention {
-        // How long data in partition should be stored. Must be greater than 0 and less than limit for this database.
-        // Default limit - 36 hours.
-        google.protobuf.Duration retention_period = 2;
-        // How much data in partition should be stored. Must be greater than 0 and less than limit for this database.
-        int64 retention_storage_bytes = 14 [(value) = ">= 0"];
+    oneof partitions {
+        // How many uniform partitions in topic. Must less than database limit. Default limit - 10.
+        int32 partitions_count = 1;
+        // 2 reserved for partition_at_keys
     }
-    // How long last written sequence number for message group should be stored. Must be greater then retention_period and less then limit for this database.  Default limit - 16 days.
-    google.protobuf.Duration message_group_seq_no_retention_period = 12;
-    // How many last written sequence number for various message groups should be stored per partition. Must be less than limit for this database.  Default limit - 6*10^6 values.
-    int64 max_partition_message_groups_seq_no_stored = 13 [(value) = ">= 0"];
-    reserved 3;
-    reserved "supported_format";
+    // How long data in partition should be stored. Must be greater than 0 and less than limit for this database.
+    // Default limit - 36 hours.
+    google.protobuf.Duration retention_period = 2;
+    // How much data in partition should be stored. Must be greater than 0 and less than limit for this database.
+    int64 retention_storage_mb = 3;
+    reserved 4; // supported_format.
     // List of allowed codecs for writers.
     // See enum Codec above for values.
-    // Writes with codec not from this list are forbiden.
-    repeated int64 supported_codecs = 4 [(size).le = 100];
-    // Max storage usage for each topic's partition. Must be less than database limit. Default limit - 130 GB.
-    int64 max_partition_storage_size = 5 [(value) = ">= 0"];
+    // Writes with codec not from this list are forbidden.
+    repeated int64 supported_codecs = 5;
     // Partition write speed in bytes per second. Must be less than database limit. Default limit - 1 MB/s.
-    int64 max_partition_write_speed = 6 [(value) = ">= 0"];
+    int64 partition_write_speed_bytes_per_second = 6;
     // Burst size for write in partition, in bytes. Must be less than database limit. Default limit - 1 MB.
-    int64 max_partition_write_burst = 7 [(value) = ">= 0"];
+    int64 partition_write_burst_bytes = 7;
 
-    // Disallows client writes. Used for mirrored topics in federation.
-    bool client_write_disabled = 8;
-    // Message for read rules description.
+    // User and server attributes of topic. Server attributes starts from "_" and will be validated by server.
+    map<string, string> attributes = 8;
+
+    // List of consumers for this topic.
+    repeated Consumer consumers = 9;
+
+    // Consumer description.
     message Consumer {
         // Must have valid not empty name as a key.
-        string name = 1 [(required) = true];
+        string name = 1;
+        // Consumer may be marked as 'important'. It means messages for this consumer will never expire due to retention.
+        // User should take care that such consumer never stalls, to prevent running out of disk space.
         // Flag that this consumer is important.
         bool important = 2;
-        // All messages with smaller timestamp of write will be skipped.
-        google.protobuf.Timestamp start_from_written_at = 3;
-        reserved 4;
-        reserved "supported_format";
+        // All messages with smaller server written_at timestamp will be skipped.
+        google.protobuf.Timestamp read_from = 3;
+        reserved 4; // supported_format
         // List of supported codecs by this consumer.
         // See enum Codec above for values.
         // supported_codecs on topic must be contained inside this list.
-        repeated int64 supported_codecs = 5 [(size).le = 100];
-
-        // Read rule version. Any non-negative integer.
-        int64 version = 6 [(value) = ">= 0"];
+        repeated int64 supported_codecs = 5;
 
-        // Client service type.
-        string service_type = 7;
+        // Attributes of consumer
+        map<string, string> attributes = 6;
     }
-
-    // List of consumer read rules for this topic.
-    repeated Consumer consumers = 9 [(size).le = 3000];
-
-    // User and server attributes of topic. Server attributes starts from "_" and will be validated by server.
-    map<string, string> attributes = 10;
 }
 
 // Create topic request sent from client to server.
 message CreateTopicRequest {
     Ydb.Operations.OperationParams operation_params = 1;
     // Topic path.
-    // e.g. /database_path/dir/my-topic
-    // or /database_path/dir/my-topic.federation-mirrors/sas
-    string path = 2 [(required) = true];
+    string path = 2;
     // Topic settings.
     TopicSettings settings = 4;
 }
@@ -535,7 +547,7 @@ message CreateTopicResult {
 message AlterTopicRequest {
     Ydb.Operations.OperationParams operation_params = 1;
     // Topic path.
-    string path = 2 [(required) = true];
+    string path = 2;
     // New topic settings to be set. All options inside should be set despite same value.
     TopicSettings settings = 4;
 }
@@ -554,7 +566,7 @@ message AlterTopicResult {
 message AddConsumerRequest {
     Ydb.Operations.OperationParams operation_params = 1;
     // Topic path.
-    string topic = 2 [(required) = true];
+    string path = 2;
     // consumers to add
     TopicSettings.Consumer consumer = 3;
 }
@@ -569,23 +581,23 @@ message AddConsumerResponse {
 message AddConsumerResult {
 }
 
-// Remove consumer request for existing topic.
-message RemoveConsumerRequest {
+// Drop consumer request for existing topic.
+message DropConsumerRequest {
     Ydb.Operations.OperationParams operation_params = 1;
     // Topic path.
-    string topic = 2 [(required) = true];
-    // Name of consumer to remove.
+    string path = 2;
+    // Name of consumer to drop.
     string consumer = 3;
 }
 
-// Remove consumer response for existing topic.
-message RemoveConsumerResponse {
+// Drop consumer response for existing topic.
+message DropConsumerResponse {
     // Result of request will be inside operation.
     Ydb.Operations.Operation operation = 1;
 }
 
-// Remove consumer result message that will be inside RemoveConsumerReponse.operation.
-message RemoveConsumerResult {
+// Drop consumer result message that will be inside DropConsumerReponse.operation.
+message DropConsumerResult {
 }
 
 // Describe topic request sent from client to server.
@@ -593,7 +605,7 @@ message DescribeTopicRequest {
     Ydb.Operations.OperationParams operation_params = 1;
 
     // Topic path.
-    string path = 2 [(required) = true];
+    string path = 2;
 
     // If this message is present, response will include runtime topic statistics.
     IncludeStats include_stats = 3;
@@ -612,7 +624,7 @@ message DescribeTopicResponse {
 
 // Describe topic result message that will be inside DescribeTopicResponse.operation.
 message DescribeTopicResult {
-    // Topic path.
+    // Description of scheme object.
     Ydb.Scheme.Entry self = 1;
     // Settings of topic.
     TopicSettings settings = 2;
@@ -628,24 +640,16 @@ message DescribeTopicResult {
             // Patition identifier inside topic.
             int64 partition_id = 1;
 
-            // Request status of partition.
-            Ydb.StatusIds.StatusCode status = 2;
-            // Issues if any.
-            repeated Ydb.Issue.IssueMessage issues = 3;
-
-            // First and next-after-last offsets of messages in partition.
-            OffsetsRange partition_offsets = 4;
+            // Partition contains messages with offsets in range [start, end).
+            OffsetsRange partition_offsets = 2;
 
             // Host name of node where partition leader is running.
-            string tablet_node = 5;
+            string tablet_node = 3;
 
             // Statistics of particular consumer, if requested.
-            ConsumerStats consumer_stats = 6;
+            ConsumerStats consumer_stats = 4;
 
             message ConsumerStats {
-                // Consumer name.
-                string name = 1;
-
                 // Offset of consumer committed message a.k.a. first not processed message.
                 // If commit_offset == end_offset then all messages from partition are processed.
                 int64 commit_offset = 2;
@@ -663,8 +667,8 @@ message DescribeTopicResult {
 
                 // Session identifier that locked and reading this partition right now.
                 string session_id = 7;
-                // Ip if node that created reading this session.
-                string client_node = 8;
+                // Ip of node that created reading this session.
+                string client_ip = 8;
                 // Host name of proxy node that processing this reading session.
                 string proxy_node = 9;