engine/order manager: Initial REST managed order updating (resolves #772) (#775)

* Initial REST managed order updating

* Apply gloriousCode's changes.go patch

* Update internal order ID handling

* Check error

* Replace string with string pointer

* Avoid nil pointers in upsert

* Update test for UpdateOrderFromDetail()

* Add tests for orders.go

* Remove unnecessary newline

* Address comments

* Add missing nil check

* Add tests for new functions in order_manager.go

* Remove empty line

* Change log level for updates from Info to Debug (keep added orders at Info)

* Initialize orders before running the timer

* [TEMP] Add verbosity for debugging

* Nil checking on exchangeManager in GetExchanges()

- exchangeManager.GetExchanges() and iExchangeManager.GetExchanges() return an error on nil
- bot.GetExchanges() wraps exchangeManager.GetExchanges() and returns an empty slice

* Revert b5afe1a46b

* Do not start the order manager runner thread

Instead, mark the order manager as running

* Remove redundant error.Is() and remove print wrapper on msg

* Add atomic blocker and waitgroup on processOrders()

* Disable unnecessary orderManager runner thread for rpcserver_test

* Remove redundant err from orderStore.getActiveOrders()

* [FIX] Populate requiresProcessing using UpsertResponse data instead of REST return data

.. because the data returned by the REST calls do not include the internal user ID's

* [TEST] Verify that processOrders() actually processes queried order data

* Remove leftover warning and add nil check on wg.Done()

* Apply suggestions from code review

Log category changes - as suggested

Co-authored-by: Adrian Gallagher <adrian.gallagher@thrasher.io>

* Return when no exchanges available

Co-authored-by: Adrian Gallagher <adrian.gallagher@thrasher.io>

engine/exchange_manager_test.go

@@ -28,7 +28,11 @@ func TestExchangeManagerAdd(t *testing.T) {
 	b := new(bitfinex.Bitfinex)
 	b.SetDefaults()
 	m.Add(b)
-	if exch := m.GetExchanges(); exch[0].GetName() != "Bitfinex" {
+	exchanges, err := m.GetExchanges()
+	if err != nil {
+		t.Error("no exchange manager found")
+	}
+	if exchanges[0].GetName() != "Bitfinex" {
 		t.Error("unexpected exchange name")
 	}
 }
@@ -36,13 +40,21 @@ func TestExchangeManagerAdd(t *testing.T) {
 func TestExchangeManagerGetExchanges(t *testing.T) {
 	t.Parallel()
 	m := SetupExchangeManager()
-	if exchanges := m.GetExchanges(); exchanges != nil {
+	exchanges, err := m.GetExchanges()
+	if err != nil {
+		t.Error("no exchange manager found")
+	}
+	if exchanges != nil {
 		t.Error("unexpected value")
 	}
 	b := new(bitfinex.Bitfinex)
 	b.SetDefaults()
 	m.Add(b)
-	if exch := m.GetExchanges(); exch[0].GetName() != "Bitfinex" {
+	exchanges, err = m.GetExchanges()
+	if err != nil {
+		t.Error("no exchange manager found")
+	}
+	if exchanges[0].GetName() != "Bitfinex" {
 		t.Error("unexpected exchange name")
 	}
 }