Improved support for tournaments feature. (#240)

## [Unreleased]

### Added

- New Go code runtime for custom functions and authoritative match handlers.

- New Tournaments feature.

- Runtime custom function triggers for leaderboard and tournament resets.

- Lua runtime AES-256 functions.

- Lua runtime token generator function now returns a second value representing the token's expiry.

- Add local cache for in-memory storage to the Lua runtime.

### Changed

- Improved Postgres compatibility on TIMESTAMPTZ types.

### Fixed

- Correctly merge new friend records when importing from Facebook.

- Log correct registered hook names at startup.

    option (google.api.http).post = "/v2/group/{group_id}/join";

  }

  rpc JoinTournament (JoinTournamentRequest) returns (google.protobuf.Empty) {

    option (google.api.http).post = "/v2/tournament/{tournament_id}/join";

  }

  // Kick a set of users from a group.

  rpc KickGroupUsers (KickGroupUsersRequest) returns (google.protobuf.Empty) {

    option (google.api.http).post = "/v2/group/{group_id}/kick";

    option (google.api.http).get = "/v2/group/{group_id}/user";

  }

  // List leaderboard records

  // List leaderboard records.

  rpc ListLeaderboardRecords (ListLeaderboardRecordsRequest) returns (LeaderboardRecordList) {

    option (google.api.http).get = "/v2/leaderboard/{leaderboard_id}";

  }

  rpc ListLeaderboardRecordsAroundOwner (ListLeaderboardRecordsAroundOwnerRequest) returns (LeaderboardRecordList) {

    option (google.api.http).get = "/v2/leaderboard/{leaderboard_id}/owner/{owner_id}";

  }

  // Fetch list of running matches.

  rpc ListMatches (ListMatchesRequest) returns (MatchList) {

    option (google.api.http).get = "/v2/match";

    };

  }

  // List current or upcoming tournaments.

  rpc ListTournaments (ListTournamentsRequest) returns (TournamentList) {

    option (google.api.http).get = "/v2/tournament";

  }

  // List tournament records.

  rpc ListTournamentRecords (ListTournamentRecordsRequest) returns (TournamentRecordList) {

    option (google.api.http).get = "/v2/tournament/{tournament_id}";

  }

  rpc ListTournamentRecordsAroundOwner (ListTournamentRecordsAroundOwnerRequest) returns (TournamentRecordList) {

    option (google.api.http).get = "/v2/tournament/{tournament_id}/owner/{owner_id}";

  }

  // List groups the current user belongs to.

  rpc ListUserGroups (ListUserGroupsRequest) returns (UserGroupList) {

    option (google.api.http).get = "/v2/user/{user_id}/group";

      body: "*"

    };

  }

  // Write a record to a tournament.

  rpc WriteTournamentRecord (WriteTournamentRecordRequest) returns (LeaderboardRecord) {

    option (google.api.http) = {

      put: "/v2/tournament/{tournament_id}",

      body: "record"

    };

  }

}

// A user with additional account details. Always the current user.

// Immediately join an open group, or request to join a closed one.

message JoinGroupRequest {

  // The group ID to join.

  // The group ID to join. The group must already exist.

  string group_id = 1;

}

// The request to join a tournament.

message JoinTournamentRequest {

  // The ID of the tournament to join. The tournament must already exist.

  string tournament_id = 1;

}

// Kick a set of users from a group.

message KickGroupUsersRequest {

  // The group ID to kick from.

  google.protobuf.Timestamp expiry_time = 10;

  // The rank of this record.

  int64 rank = 11;

  // The maximum number of score updates allowed by the owner.

  uint32 max_num_score = 12;

}

// A set of leaderboard records, may be part of a leaderboard records page or a batch of individual records.

  string group_id = 1;

}

// List leaerboard records from a given leaderboard around the owner.

message ListLeaderboardRecordsAroundOwnerRequest {

  // The ID of the tournament to list for.

  string leaderboard_id = 1;

  // Max number of records to return. Between 1 and 100.

  google.protobuf.UInt32Value limit = 2;

  // The owner to retrieve records around.

  string owner_id = 3;

}

// List leaderboard records from a given leaderboard.

message ListLeaderboardRecordsRequest {

  // The ID of the leaderboard to list for.

  string cursor = 4; // value from StorageObjectList.cursor.

}

// List tournament records from a given tournament around the owner.

message ListTournamentRecordsAroundOwnerRequest {

  // The ID of the tournament to list for.

  string tournament_id = 1;

  // Max number of records to return. Between 1 and 100.

  google.protobuf.UInt32Value limit = 2;

  // The owner to retrieve records around.

  string owner_id = 3;

}

// List tournament records from a given tournament.

message ListTournamentRecordsRequest {

  // The ID of the tournament to list for.

  string tournament_id = 1;

  // One or more owners to retrieve records for.

  repeated string owner_ids = 2;

  // Max number of records to return. Between 1 and 100.

  google.protobuf.Int32Value limit = 3;

  // A next or previous page cursor.

  string cursor = 4;

}

// List active/upcoming tournaments based on given filters.

message ListTournamentsRequest {

  // The start of the categories to include. Defaults to 0.

  google.protobuf.UInt32Value category_start = 1;

  // The end of the categories to include. Defaults to 128.

  google.protobuf.UInt32Value category_end = 2;

  // The start time for tournaments. Defaults to epoch.

  google.protobuf.UInt32Value start_time = 3;

  // The end time for tournaments. Defaults to +1 year from current Unix time.

  google.protobuf.UInt32Value end_time = 4;

  // Max number of records to return. Between 1 and 100.

  google.protobuf.Int32Value limit = 6;

  // A next page cursor for listings (optional).

  string cursor = 8;

}

// List the groups a user is part of, and their relationship to each.

message ListUserGroupsRequest {

  // ID of the user.

  string cursor = 2;

}

// A tournament on the server.

message Tournament {

  // The ID of the tournament.

  string id = 1;

  // The title for the tournament.

  string title = 2;

  // The description of the tournament. May be blank.

  string description = 3;

  // The category of the tournament. e.g. "vip" could be category 1.

  uint32 category = 4;

  // ASC or DESC sort mode of scores in the tournament.

  uint32 sort_order = 5;

  // The current number of players in the tournament.

  uint32 size = 6;

  // The maximum number of players for the tournament.

  uint32 max_size = 7;

  // The maximum score updates allowed per player for the current tournament.

  uint32 max_num_score = 8;

  // True if the tournament is active and can enter. A computed value.

  bool can_enter = 9;

  // The UNIX timestamp when the tournament stops being active until next reset. A computed value.

  uint32 end_active = 10;

  // The UNIX timestamp when the tournament is next playable. A computed value.

  uint32 next_reset = 11;

  // Additional information stored as a JSON object.

  string metadata = 12;

  // The UNIX time when the tournament was created.

  google.protobuf.Timestamp create_time = 13;

  // The UNIX time when the tournament will start.

  google.protobuf.Timestamp start_time = 14;

  // The UNIX time when the tournament will be stopped.

  google.protobuf.Timestamp end_time = 15;

}

// A list of tournaments.

message TournamentList {

  // The list of tournaments returned.

  repeated Tournament tournaments = 1;

  // A pagination cursor (optional).

  string cursor = 2;

}

// A set of tournament records which may be part of a tournament records page or a batch of individual records.

message TournamentRecordList {

  // A list of tournament records.

  repeated LeaderboardRecord records = 1;

  // A batched set of tournament records belonging to specified owners.

  repeated LeaderboardRecord owner_records = 2;

  // The cursor to send when retireving the next page (optional).

  string next_cursor = 3;

  // The cursor to send when retrieving the previous page (optional).

  string prev_cursor = 4;

}

// Update a user's account details.

message UpdateAccountRequest {

  // The username of the user's account.

  // The ID of the leaderboard to write to.

  string leaderboard_id = 1;

  // Record data.

  // Record input.

  LeaderboardRecordWrite record = 2;

}

  // The objects to store on the server.

  repeated WriteStorageObject objects = 1;

}

// A request to submit a score to a tournament.

message WriteTournamentRecordRequest {

  // Record values to write.

  message TournamentRecordWrite {

    // The score value to submit.

    int64 score = 1;

    // An optional secondary value.

    int64 subscore = 2;

    // A JSON object of additional properties (optional).

    string metadata = 3;

  }

  // The tournament ID to write the record for.

  string tournament_id = 1;

  // Record input.

  TournamentRecordWrite record = 2;

}