[Market] Create API method Game.market.getOrderById()

Dissi

This way we don't have to filter all orders every time if we want to "buy out" a certain order over multiple ticks, but can quickly access it directly in O(1) fashion.

The same method like Game.getObjectById() would be recommended.

coteyr

YES!!!!

I had this one bite me Yesterday. I was trying to finish of preparing an order for 10,000 O, only for that order to "vanish" (someone else finished it). Because of the cost of getAllOrders I wasn't able to check and see. Had I been able to detect the order not being available anymore I would have reacted, Either by picking another resource, or finding another order. The current way, I had to wait for deal() to error out, then try to find another order, only to have that one require a different cost, and then .....

Getting a single order would have enabled a per tick check (or at least a per round trip for the creep check) to see if the order I was working on was still valid, or if I needed to do something else.

Mototroller

Dissi: doesn't it works the desired way?

let order = Game.market.getAllOrders()[id];

Seems like without filtering it's possible to get cached hash-map of all orders fast enough. Moreover, u can use your own caching, smth like:

function orders() { return Memory.orders || (Memory.orders = Game.market.getAllOrders()); }

Simplified, but only fix to be implemented is checking the current tick (Game.time === update_time). Works pretty nice for huge amount of calls in the same tick.

Dissi

It does not sadly. It returns an array, not an object. also storing them in Memory is quite a bad idea for CPU-reasons so storing a single transaction ID is definitely a plus. If I were to use a filter for the orders { id : 'someId' } it will loop over ALL orders - horrendous for CPU.

Mototroller

Oh, yep, I've missed that array is returning. Using some wrapper, so ye, my cache actually contains only bid-ask, ids and some other technical info, built only once per tick and it's about ~1Kb, but there aren't full orders here.

saturn7

Also caching orders is a bad idea, as players can now change the order price. With a fast method to access an order by id, we could easily check whether the price is still the same.

Mototroller

@ saturn7: I think, it was meant that reducing an Game.market.getAllOrders() to hashmap takes a long time, and it can't be saved into Memory due to huge size, and it will be used several time per one tick.

@ Dissi: I've found a pretty useful solution (see below). Not sure where exactly "global" object is stored at runtime under hood, but there are some statistics: ~1.0 cpu -- first call, ~0.01 cpu -- every subsequent calls.

global.orders = function() {
  if((global.__orders_update || 0) !== Game.time || !global.__orders) {
    global.__orders = _.reduce(Game.market.getAllOrders(), function(res, o) {
      res[o.id] = o;
      return res;
    },{});
    global.__orders_update = Game.time;
  }
  return global.__orders;
}