syntax = "proto3";

package stream;

option go_package = "./proto;stream";

service Stream {
	rpc CreateChannel(CreateChannelRequest) returns (CreateChannelResponse) {}
	rpc SendMessage(SendMessageRequest) returns (SendMessageResponse) {}
	rpc ListMessages(ListMessagesRequest) returns (ListMessagesResponse) {}
	rpc ListChannels(ListChannelsRequest) returns (ListChannelsResponse) {}
}

message Message {
	// id of the message
	string id = 1;
	// text of the message
	string text = 2;
	// time of message creation
	string timestamp = 3;
	// the channel name
	string channel = 4;
	// the associated metadata
	map<string,string> metadata = 5;
}

message Channel {
	// name of the channel
	string name = 1;
	// description for the channel
	string description = 2;
	// last activity time
	string last_active = 3;
}

// Create a channel with a given name and description. Channels are created automatically but 
// this allows you to specify a description that's persisted for the lifetime of the channel.
message CreateChannelRequest {
	// name of the channel
	string name = 1;
	// description for the channel
	string description = 2;
}

message CreateChannelResponse {}

// Send a message to the stream.
message SendMessageRequest {
	// The channel to send to
	string channel = 1;
	// The message text to send
	string text = 2;
}

message SendMessageResponse {}

// List all the active channels
message ListChannelsRequest {
}

message ListChannelsResponse {
	repeated Channel channels = 1;
}

// List messages for a given channel
message ListMessagesRequest {
	// The channel to subscribe to
	string channel = 1;
	// number of message to return
	int32 limit = 2;
}

message ListMessagesResponse {
	// The channel subscribed to
	string channel = 1;
	// Messages are chronological order
	repeated Message messages = 2;
}