messages.proto

syntax = "proto3";

// used in production: YES
// messages should not be deleted and
// field numbers should not be changed anymore.

package loon;

import "google/protobuf/timestamp.proto";

option go_package = "/pb";

// Preparation

message Constraints {
  uint64 chunk_size = 1;
  uint64 max_content_size = 2;
  repeated string accepted_content_types = 3;
  uint32 cache_duration = 4;
}

// <-
message Hello {
  string base_url = 1;
  string client_id = 2;
  bytes connection_secret = 3;
  Constraints constraints = 4;
}

// Requests

// <-
message Request {
  uint64 id = 1;
  google.protobuf.Timestamp timestamp = 2;
  string path = 3;
}

// Responses

// ->
message EmptyResponse {
  uint64 request_id = 1;
}

// ->
message ContentHeader {
  uint64 request_id = 1;
  string content_type = 2;
  uint64 content_size = 3;
  optional uint32 max_cache_duration = 4;
  optional string filename = 5;
}

// ->
message ContentChunk {
  uint64 request_id = 1;
  uint64 sequence = 2;
  bytes data = 3;
}

// Events

// <-
message Success {
  uint64 request_id = 1;
}

// <-
message RequestClosed {
  uint64 request_id = 1;
  string message = 2;
}

// ->
message CloseResponse {
  uint64 request_id = 1;
}

// Error handling

// <-
// Close message, which is sent right before the server closes the session.
message Close {
  enum Reason {
    REASON_UNSPECIFIED = 0;
    REASON_CLOSED = 1;
    REASON_ERROR = 2;
    REASON_INVALID_CLIENT_MESSAGE = 3;
    REASON_INVALID_REQUEST_ID = 4;
    REASON_FORBIDDEN_CONTENT_TYPE = 5;
    REASON_INVALID_CONTENT_SIZE = 6;
    REASON_CONTENT_CHUNK_OUT_OF_SEQUENCE = 7;
    REASON_INVALID_CHUNK_SIZE = 8;
    REASON_INVALID_FILENAME = 9;
    REASON_TIMED_OUT = 10;
  }

  Reason reason = 1;
  string message = 2;
}

// Message encapsulation

// ->
message ClientMessage {
  oneof data {
    EmptyResponse empty_response = 1;
    ContentHeader content_header = 2;
    ContentChunk content_chunk = 3;
    CloseResponse close_response = 4;
  }
}

// <-
message ServerMessage {
  oneof data {
    Hello hello = 1;
    Request request = 2;
    Success success = 3;
    RequestClosed request_closed = 4;
    Close close = 5;
  }
}