playground.proto

syntax = "proto3";
package playground;

service Playground {
    // Takes two operands and an operator and returns the result.
    rpc Math(MathRequest) returns (MathResponse);
    // Counts down for the provided duration, sending a message each second.
    rpc Countdown(CountdownRequest) returns (stream CountdownResponse);
    // Consumes streaming strings and returns the digested hash at the end.
    rpc Hash(stream HashRequest) returns (HashResponse);
    // Play a game of hangman.
    rpc Hangman(stream HangmanRequest) returns (stream HangmanResponse);
    // This procedure returns sensible data and thus requires you to
    // authenticate by providing the SHA256 hash of the admin's password (which
    // is "rusty rust"). You can provide the hash in one of two ways:
    // - Via a "password" metadata, as an hex string
    // - Via a "password-bin" metadata, in binary form
    rpc Secret(SecretRequest) returns (SecretResponse);
}

message MathRequest {
    enum Op {
        ADD = 0;
        SUBTRACT = 1;
        MULTIPLY = 2;
        DIVIDE = 3;
    }
    Op op = 1;
    // Left hand side operand.
    float lhs = 2;
    // Right hand side operand.
    float rhs = 3;
}

message MathResponse {
    float result = 1;
}

message CountdownRequest {
    // How long to count down for.
    int32 seconds = 1;
}

message CountdownResponse {
    // How many seconds are left. 0 means the countdown has terminated.
    int32 left = 1;
}

message HashRequest {
    string piece = 1;
}

message HashResponse {
    // The hash of the entire streamed content.
    bytes hash = 1;
}

message HangmanRequest {
    // Leave empty when launching the request. Use a 1-length string to guess
    // a letter afterwards.
    optional string letter = 1;
}

message HangmanResponse {
    // A string with "_" placeholders that must be guessed by the player.
    string state = 1;
    // How many wrong guesses can be made still.
    int32 lives_left = 2;

    // If the message contains a string with no placeholders, then the game is
    // won. If the message has -1 lives left, the game is lost. In either case
    // the server will commit the connection after sending the message.
}

message SecretRequest {}

message SecretResponse {
    string secret = 1;
}