gctrpc/order manager: Add ModifyOrder endpoint (#724)

* gctcli: modifyorder stubs

* gctcli: add ModifyOrderRequest and ModifyOrderResponse in rpc.proto

* gctcli: regenerate rpc.pb.go after the addition of ModifyOrder structs

* gctrpc: add ModifyOrder() and regenerate dependent files

* gctcli: modifyorder command now uses newly generated ModifyOrder() RPC

* exchanges/order/orders.go: use time.Time.Equal() instead of ==

* gctrpc: update ModifyOrderRequest and ModifyResponse and regenerate gRPC

* gctcli/commands: rework modifyorder

* engine: implement RPCServer.ModifyOrder

* engine: commit an initial version OrderManager.Modify(), still does not update state of managed orders

* engine: OrderManager.Modify now updates the inner state of managed orders, but introduces race conditions, needs fixes

* engine/order_manager.go: comply with golangci-lint

* gctcli: fix getOrderCommand.ArgsUsage

* gctcli: fix getModifyOrderCommand args and ArgsUsage

* engine: OrderManager.Modify() now correctly updates price of modified order

* engine: RPCServer.ModifyOrder now uses checkParams() as advised

* exchanges: (1) IBotExchange.ModifyOrder now returns a Modify struct, (2) all exchanges are updated to comply with that change

* exchanges/order: Detail.UpdateOrderFromModify also updates the ID

* engine/order_manager: add store.modifyExisting() and use it in OrderManager.Modify to update (on success) the state of the modified order

* exchanges: Bitfinex.ModifyOrder() now returns the ID in case of an error

* engine: OrdetManager.Modify() now emits an order event

* exchanges/bithumb: proper order.payment_currency key

* engine/order_manager: populate more Modify fields as they are needed by (some) exchanges, add comments

* engine: test OrderManager.Modify()

* engine: test store.modifyExisting()

* engine: write a docstring for store.modifyExisting

* engine: OrderManager.Modify() now also sets Modify.Price and Modify.Amount in case of zero values

* engine: TestOrderManager_Modify() now verify the effects of price and/or amount set to 0

* engine: OrderManger.Modify() now uses the commsManager to let observers know of errors

* engine: TestOrderManager_Modify() uses t.Fatal()

* engine: TestOrderManager_Modify() and TestStore_modifyOrder() supply t.Error() with proper messages

* exchanges/order_manager_test: fix a golangci-lint complaint

* engine/order_manager: fix an error comparison bug and simplify

* gctcli/commands: check if either price or amount is set, otherwise we would waste an API call

cmd/exchange_wrapper_issues/main.go

@@ -572,8 +572,7 @@ func testWrappers(e exchange.IBotExchange, base *exchange.Base, config *Config)
 			Price:  config.OrderSubmission.Price,
 			Amount: config.OrderSubmission.Amount,
 		}
-		var modifyOrderResponse string
-		modifyOrderResponse, err = e.ModifyOrder(&modifyRequest)
+		modifyOrderResponse, err := e.ModifyOrder(&modifyRequest)
 		msg = ""
 		if err != nil {
 			msg = err.Error()

cmd/gctcli/commands.go

@@ -1450,7 +1450,7 @@ func getManagedOrders(c *cli.Context) error {
 var getOrderCommand = &cli.Command{
 	Name:      "getorder",
 	Usage:     "gets the specified order info",
-	ArgsUsage: "<exchange> <order_id> <pair>",
+	ArgsUsage: "<exchange> <asset> <pair> <order_id>",
 	Action:    getOrder,
 	Flags: []cli.Flag{
 		&cli.StringFlag{
@@ -2236,6 +2236,39 @@ var cancelAllOrdersCommand = &cli.Command{
 	},
 }
 
+var modifyOrderCommand = &cli.Command{
+	Name:      "modifyorder",
+	Usage:     "modify price and/or amount of a previously submitted order",
+	ArgsUsage: "<exchange> <asset> <pair> <order_id>",
+	Action:    modifyOrder,
+	Flags: []cli.Flag{
+		&cli.StringFlag{
+			Name:  "exchange",
+			Usage: "exchange this order is submitted to",
+		},
+		&cli.StringFlag{
+			Name:  "asset",
+			Usage: "required asset type",
+		},
+		&cli.StringFlag{
+			Name:  "pair",
+			Usage: "required trading pair",
+		},
+		&cli.StringFlag{
+			Name:  "order_id",
+			Usage: "id of the order to be modified",
+		},
+		&cli.Float64Flag{
+			Name:  "price",
+			Usage: "new order price",
+		},
+		&cli.Float64Flag{
+			Name:  "amount",
+			Usage: "new order amount",
+		},
+	},
+}
+
 func cancelAllOrders(c *cli.Context) error {
 	var exchangeName string
 	if c.IsSet("exchange") {
@@ -2269,6 +2302,98 @@ func cancelAllOrders(c *cli.Context) error {
 	return nil
 }
 
+func modifyOrder(c *cli.Context) error {
+	if c.NArg() == 0 && c.NumFlags() == 0 {
+		return cli.ShowCommandHelp(c, "modifyorder")
+	}
+
+	// Parse positional arguments.
+	var exchangeName string
+	var orderID string
+	var currencyPair string
+	var assetType string
+
+	if c.IsSet("exchange") {
+		exchangeName = c.String("exchange")
+	} else {
+		exchangeName = c.Args().First()
+	}
+	if !validExchange(exchangeName) {
+		return errInvalidExchange
+	}
+
+	if c.IsSet("asset") {
+		assetType = c.String("asset")
+	} else {
+		assetType = c.Args().Get(1)
+	}
+	assetType = strings.ToLower(assetType)
+	if !validAsset(assetType) {
+		return errInvalidAsset
+	}
+
+	if c.IsSet("pair") {
+		currencyPair = c.String("pair")
+	} else {
+		currencyPair = c.Args().Get(2)
+	}
+	if !validPair(currencyPair) {
+		return errInvalidPair
+	}
+
+	p, err := currency.NewPairDelimiter(currencyPair, pairDelimiter)
+	if err != nil {
+		return err
+	}
+
+	if c.IsSet("order_id") {
+		orderID = c.String("order_id")
+	} else {
+		orderID = c.Args().Get(3)
+	}
+
+	// Parse optional flags.
+	var price float64
+	var amount float64
+
+	if c.IsSet("price") {
+		price = c.Float64("price")
+	}
+	if c.IsSet("amount") {
+		amount = c.Float64("amount")
+	}
+	if price == 0 && amount == 0 {
+		return errors.New("either --price or --amount should be present")
+	}
+
+	// Setup gRPC, make a request and display response.
+	conn, err := setupClient()
+	if err != nil {
+		return err
+	}
+	defer conn.Close()
+
+	client := gctrpc.NewGoCryptoTraderClient(conn)
+	result, err := client.ModifyOrder(context.Background(), &gctrpc.ModifyOrderRequest{
+		Exchange: exchangeName,
+		OrderId:  orderID,
+		Pair: &gctrpc.CurrencyPair{
+			Delimiter: p.Delimiter,
+			Base:      p.Base.String(),
+			Quote:     p.Quote.String(),
+		},
+		Asset:  assetType,
+		Price:  price,
+		Amount: amount,
+	})
+	if err != nil {
+		return err
+	}
+
+	jsonOutput(result)
+	return nil
+}
+
 var getEventsCommand = &cli.Command{
 	Name:   "getevents",
 	Usage:  "gets all events",

cmd/gctcli/main.go

@@ -126,6 +126,7 @@ func main() {
 		cancelOrderCommand,
 		cancelBatchOrdersCommand,
 		cancelAllOrdersCommand,
+		modifyOrderCommand,
 		getEventsCommand,
 		addEventCommand,
 		removeEventCommand,