Index iterators

By our gameplay, all caught pokémons are returned back to the map. We do this for all pokémons on the map every 60 seconds using respawn() method. We iterate through pokémons by status using Tarantool index iterator function index_object:pairs() and reset the statuses of all "caught" pokémons back to "active" using box.space.pokemons:update().

 
respawn = function(self)    fiber.name('Respawn fiber')    for _, tuple in box.space.pokemons.index.status:pairs(           self.state.CAUGHT) do        box.space.pokemons:update(            tuple[self.ID],            {{'=', self.STATUS, self.state.ACTIVE}}        )    end end

For readability, we introduce named fields:

ID = 1, STATUS = 2,

The complete implementation of start() now looks like this:

 
-- create game objectstart = function(self)    -- create spaces and indexes    box.once('init', function()       box.schema.create_space('pokemons')       box.space.pokemons:create_index(           "primary", {type = 'hash', parts = {1, 'unsigned'}}       )       box.space.pokemons:create_index(           "status", {type = "tree", parts = {2, 'str'}}       )    end)    -- create models    local ok_m, pokemon = avro.create(schema.pokemon)    local ok_p, player = avro.create(schema.player)    if ok_m and ok_p then        -- compile models        local ok_cm, compiled_pokemon = avro.compile(pokemon)        local ok_cp, compiled_player = avro.compile(player)        if ok_cm and ok_cp then            -- start the game            self.pokemon_model = compiled_pokemon            self.player_model = compiled_player            self.respawn()            log.info('Started')            return true         else            log.error('Schema compilation failed')         end    else        log.info('Schema creation failed')    end    return falseend