Simple C# 1Brocker API Program — Step-by-Step Guide

Overview

A Simple C# 1Brocker API Program shows how to connect to the 1Brocker trading/API service (assumed REST or WebSocket), authenticate, make basic requests (get market data, place an order, check order status), and handle responses and errors. The guide below assumes a REST API with JSON over HTTPS and uses HttpClient in .NET.

Prerequisites

Tooling: .NET 6+ SDK, IDE (Visual Studio / VS Code).
Libraries: System.Net.Http (built-in). Optionally Newtonsoft.Json or System.Text.Json for JSON.
Credentials: API key and secret from 1Brocker (store securely; don’t hardcode).

Project setup

Create a console app:

bash
dotnet new console -n OneBrockerClient cd OneBrockerClient

Add JSON library (optional):

bash
dotnet add package Newtonsoft.Json

Authentication pattern (example)

Many trading APIs use API key + secret with HMAC signature or Bearer tokens.
Example HMAC header creation (pseudocode):
- Create message = method + path + timestamp + body
- signature = HMACSHA256(secret, message)

Example C# code (REST, synchronous flow)

csharp
using System; using System.Net.Http; using System.Net.Http.Headers; using System.Security.Cryptography; using System.Text; using System.Threading.Tasks; using Newtonsoft.Json; class OneBrockerClient { private readonly HttpClient _http; private readonly string _apiKey; private readonly string _apiSecret; private readonly string _baseUrl = “https://api.1brocker.example”; // replace with real base public OneBrockerClient(string apiKey, string apiSecret) { _apiKey = apiKey; _apiSecret = apiSecret; _http = new HttpClient(); _http.BaseAddress = new Uri(_baseUrl); _http.DefaultRequestHeaders.Accept.Add(new MediaTypeWithQualityHeaderValue(“application/json”)); } private string Sign(string method, string path, string timestamp, string body) { var message = \("{method}{path}{timestamp}{body}"; using var hmac = new HMACSHA256(Encoding.UTF8.GetBytes(_apiSecret)); var sig = hmac.ComputeHash(Encoding.UTF8.GetBytes(message)); return Convert.ToBase64String(sig); } private void AddAuthHeaders(HttpRequestMessage req, string body = "") { var ts = DateTimeOffset.UtcNow.ToUnixTimeSeconds().ToString(); var sig = Sign(req.Method.Method, req.RequestUri.PathAndQuery, ts, body); req.Headers.Add("API-Key", _apiKey); req.Headers.Add("Timestamp", ts); req.Headers.Add("Signature", sig); } public async Task<string> GetTickerAsync(string symbol) { var path = \)”/v1/market/ticker?symbol={symbol}“; var req = new HttpRequestMessage(HttpMethod.Get, path); AddAuthHeaders(req); var resp = await _http.SendAsync(req); resp.EnsureSuccessStatusCode(); return await resp.Content.ReadAsStringAsync(); } public async Task<string> PlaceOrderAsync(string symbol, string side, decimal quantity, decimal price) { var path = ”/v1/order”; var bodyObj = new { symbol, side, quantity, price }; var body = JsonConvert.SerializeObject(bodyObj); var req = new HttpRequestMessage(HttpMethod.Post, path) { Content = new StringContent(body, Encoding.UTF8, “application/json”) }; AddAuthHeaders(req, body); var resp = await http.SendAsync(req); resp.EnsureSuccessStatusCode(); return await resp.Content.ReadAsStringAsync(); } }

Usage example

csharp
static async Task Main() { var apiKey = Environment.GetEnvironmentVariable(“OB_API_KEY”); var apiSecret = Environment.GetEnvironmentVariable(“OB_API_SECRET”); var client = new OneBrockerClient(apiKey, apiSecret); var ticker = await client.GetTickerAsync(“BTCUSD”); Console.WriteLine(“Ticker: “ + ticker); var order = await client.PlaceOrderAsync(“BTCUSD”, “buy”, 0.001m, 45000m); Console.WriteLine(“Order response: “ + order); }

Error handling and retries

Check HTTP status codes; handle 4xx (client) vs 5xx (server).

Implement exponential backoff for transient failures.

Log and surface API error messages.

Security best practices

Store API secrets in environment variables or a secure vault.

Use TLS (HTTPS) and validate certificates.

Limit API key permissions and rotate keys periodically.

Testing and debugging

Use a sandbox/test API endpoint if provided.

Log request/response (without secrets) for debugging.

Write unit tests by mocking HttpClient (e.g., using HttpMessageHandler).

Next steps

Add WebSocket handling for real-time data if 1Brocker supports it.

Implement order book management, position tracking, and persistence.

Add rate-limit handling and connection pooling.

Simple C# 1Brocker API Program — Step-by-Step Guide