services/crypto/proto/crypto.proto

syntax = "proto3";

package crypto;

option go_package = "./proto;crypto";

service Crypto {
	rpc News(NewsRequest) returns (NewsResponse) {}
	rpc Quote(QuoteRequest) returns (QuoteResponse) {}
	rpc Price(PriceRequest) returns (PriceResponse) {}
	rpc History(HistoryRequest) returns (HistoryResponse) {}
	rpc Symbols(SymbolsRequest) returns (SymbolsResponse) {}
}

message Article {
	// title of the article
	string title = 1;
	// its description	
	string description = 2;
	// the source url
	string url = 3;
	// the date published
	string date = 4;
	// the source
	string source = 5;
}

// Get news related to a currency
message NewsRequest {
	// cryptocurrency ticker to request news for e.g BTC
	string symbol = 1;
}

message NewsResponse {
	// symbol requested for
	string symbol = 1;
	// list of articles
	repeated Article articles = 2;
}

// Get the last price for a given crypto ticker
message PriceRequest {
	// the crypto symbol e.g BTCUSD
	string symbol = 1;
}

message PriceResponse {
	// the crypto symbol e.g BTCUSD
	string symbol = 1;
	// the last price
	double price = 2;
}

// Get the last quote for a given crypto ticker
message QuoteRequest {
	// the crypto symbol e.g BTCUSD
	string symbol = 1;
}

message QuoteResponse {
	// the crypto symbol
	string symbol = 1;
	// the asking price
	double ask_price = 2;
	// the bidding price
	double bid_price = 3;
	// the ask size
	double ask_size = 4;
	// the bid size
	double bid_size = 5;
	// the UTC timestamp of the quote
	string timestamp = 6;
}


// Returns the history for the previous close
message HistoryRequest {
	// the crypto symbol e.g BTCUSD
	string symbol = 1;
}

message HistoryResponse {
	// the crypto symbol
	string symbol = 1;
	// the open price
	double open = 2;
	// the close price
	double close = 3;
	// the peak price
	double high = 4;
	// the low price
	double low = 5;
	// the volume
	double volume = 6;
	// the date
	string date = 7;
}

// Returns the full list of supported symbols
message SymbolsRequest {}

message SymbolsResponse {
	repeated Symbol symbols = 1;
}

message Symbol {
	string symbol = 1;
	string name = 2;
}