dex/client/go

LX Trading Client

Multi-protocol programmatic trading client for LX. Default build is WebSocket-only; gRPC is opt-in via a build tag.

Features

• WebSocket transport (always available, default)
• gRPC transport (opt-in, behind the grpc build tag)
• Unified Interface: Same API across both transports
• Multiple Usage Modes: Package import, CLI commands, or interactive shell
• Real-time Streaming: Market data subscriptions via WebSocket or gRPC streams

Installation

# Default build — WebSocket only, zero gRPC code compiled in.
go build -o lx-client .

# With gRPC support (adds google.golang.org/grpc to the binary).
go build -tags=grpc -o lx-client .

Without the grpc build tag, -protocol=grpc, the switch grpc interactive command, and the ping / info commands report that gRPC is not compiled in. WebSocket-only consumers ship a smaller binary with no gRPC runtime.

Quick Start

WebSocket (Default)

# Interactive mode
./lx-client -i

# Single command
./lx-client place_order BTC-USD buy limit 50000 0.1

# With authentication
./lx-client -key mykey -secret mysecret -i

gRPC (requires -tags=grpc build)

# Rebuild with the grpc tag first.
go build -tags=grpc -o lx-client .

# Interactive mode via gRPC
./lx-client -protocol grpc -i

# Single command via gRPC
./lx-client -protocol grpc get_positions

# Custom gRPC endpoint
./lx-client -protocol grpc -grpc-addr exchange.lux.network:9090 ping

Command-Line Options

Flag	Default	Description
-protocol	ws	Protocol: ws or grpc
-ws-url	ws://localhost:8081	WebSocket server URL
-grpc-addr	localhost:9090	gRPC server address
-key		API key for authentication
-secret		API secret for authentication
-i	false	Interactive mode
-v	false	Verbose output

Commands

Trading

Command	Description
place_order <symbol> <side> <type> <price> <size>	Place a new order
cancel_order <order_id>	Cancel an existing order
get_orders	List all open orders
get_positions	List all positions

Market Data

Command	Description
subscribe <symbol>	Subscribe to orderbook updates
get_orderbook <symbol>	Get orderbook snapshot

Connection

Command	Description
auth <key> <secret>	Authenticate (WebSocket only)
switch <ws|grpc>	Switch active protocol
protocol	Show current protocol
ping	Test connectivity (gRPC only)
info	Show node info (gRPC only)

Programmatic Usage

Import the client package for programmatic trading:

package main

import (
    "context"
    "fmt"
    "log"

    client "github.com/luxfi/dex/client/go"
)

func main() {
    ctx := context.Background()

    // --- WebSocket Client ---
    wsClient, err := client.NewWsClient("ws://localhost:8081", false)
    if err != nil {
        log.Fatal(err)
    }
    defer wsClient.Close()

    // Wait for connection
    if err := wsClient.WaitConnected(5 * time.Second); err != nil {
        log.Fatal(err)
    }

    // Authenticate
    if err := wsClient.Auth("api_key", "api_secret"); err != nil {
        log.Fatal(err)
    }

    // Place order
    order := &client.Order{
        Symbol: "BTC-USD",
        Side:   "buy",
        Type:   "limit",
        Price:  50000,
        Size:   0.1,
    }
    resp, err := wsClient.PlaceOrder(ctx, order)
    if err != nil {
        log.Fatal(err)
    }
    fmt.Printf("Order placed: %d\n", resp.OrderID)

    // --- gRPC Client ---
    grpcClient, err := client.NewGrpcClient("localhost:9090", false)
    if err != nil {
        log.Fatal(err)
    }
    defer grpcClient.Close()

    // Test connectivity
    latency, err := grpcClient.Ping(ctx)
    if err != nil {
        log.Fatal(err)
    }
    fmt.Printf("Latency: %v\n", latency)

    // Get positions
    positions, err := grpcClient.GetPositions(ctx)
    if err != nil {
        log.Fatal(err)
    }
    for _, pos := range positions {
        fmt.Printf("Position: %s %.4f @ %.2f\n", pos.Symbol, pos.Size, pos.EntryPrice)
    }
}

Using the Client Interface

Both WsClient and GrpcClient implement the Client interface for protocol-agnostic code:

package main

import (
    "context"
    "log"

    client "github.com/luxfi/dex/client/go"
)

func trade(c client.Client) error {
    ctx := context.Background()

    // Works with either WebSocket or gRPC
    positions, err := c.GetPositions(ctx)
    if err != nil {
        return err
    }

    for _, pos := range positions {
        log.Printf("[%s] Position: %s %.4f", c.Protocol(), pos.Symbol, pos.Size)
    }
    return nil
}

func main() {
    // WebSocket
    ws, _ := client.NewWsClient("ws://localhost:8081", false)
    defer ws.Close()
    trade(ws)

    // gRPC
    grpc, _ := client.NewGrpcClient("localhost:9090", false)
    defer grpc.Close()
    trade(grpc)
}

Client Manager for Multi-Protocol

Use ClientManager to manage multiple connections and switch protocols at runtime:

package main

import (
    "context"
    "log"

    client "github.com/luxfi/dex/client/go"
)

func main() {
    ctx := context.Background()
    mgr := client.NewClientManager()

    // Connect both protocols
    mgr.ConnectWs("ws://localhost:8081", false)
    mgr.ConnectGrpc("localhost:9090", false)
    defer mgr.Close()

    // Use WebSocket by default
    orders, _ := mgr.Active().GetOrders(ctx)
    log.Printf("Orders via %s: %d", mgr.Active().Protocol(), len(orders))

    // Switch to gRPC
    mgr.SwitchProtocol(client.ProtocolGRPC)
    orders, _ = mgr.Active().GetOrders(ctx)
    log.Printf("Orders via %s: %d", mgr.Active().Protocol(), len(orders))
}

Protocol Comparison

Feature	WebSocket	gRPC
Connection	Persistent	Per-call or streaming
Auth	API key/secret	Metadata (extensible)
Streaming	Native	Server-side streaming
Latency	Low	Very low
Best for	Real-time updates	High-throughput RPC

Examples

Place and Monitor Order

# Place order and watch for updates
./lx-client -i
> subscribe BTC-USD
> place_order BTC-USD buy limit 50000 0.1
> get_orders

High-Frequency Trading Setup

# Use gRPC for lowest latency
./lx-client -protocol grpc -grpc-addr exchange.lux.network:9090 -v ping

Protocol Switching

./lx-client -i
> protocol
Active protocol: ws
> switch grpc
Switch failed: grpc client not connected
# Must connect to both protocols for runtime switching

Order Types

• limit - Limit order
• market - Market order
• stop - Stop order
• stop_limit - Stop-limit order

Order Sides

• buy - Buy order
• sell - Sell order

Server Endpoints

Protocol	Default	Environment
WebSocket	ws://localhost:8081	Development
WebSocket	wss://api.lux.exchange	Production
gRPC	localhost:9090	Development
gRPC	grpc.lux.exchange:443	Production

Error Handling

The client returns descriptive errors for common issues:

resp, err := client.PlaceOrder(ctx, order)
if err != nil {
    // Check error type
    switch {
    case strings.Contains(err.Error(), "connection closed"):
        // Reconnect
    case strings.Contains(err.Error(), "timeout"):
        // Retry
    default:
        log.Printf("Order failed: %v", err)
    }
}

Building from Source

cd /path/to/lx/dex/client/go
go mod tidy

# Default — WebSocket only.
go build -o lx-client .

# With gRPC support.
go build -tags=grpc -o lx-client .

Testing

go test -v ./...