Epicor REST API Integration Specialist

REST v2 & OData v4 Architecture

Epicor Kinetic's REST API v2 uses the standard OData v4 framework. This allows external systems to interact with standard Business Objects (such as SalesOrder, Customer, or JobEntry) using standardized JSON payloads and HTTPS verbs (GET, POST, PATCH, DELETE).

Unlike REST v1, v2 enforces a double authentication model:

• X-API-Key: A static GUID generated in Epicor's API Key Maintenance. This authenticates the external client application calling the server.
• Authorization Header: A standard OAuth2 bearer token or Base64 encoded Basic credentials. This establishes the security privileges of the active system user.

C# HttpClient Request Implementation

When interfacing Epicor with third-party portals, I write optimized, asynchronous C# classes using HttpClient. This prevents client freeze-ups and ensures clean JSON serialization.

Here is an example structure of a secure GET query that retrieves active client records with OData pagination parameters ($top and $filter):

// Configured OData call using HttpClient in C#
using (var client = new HttpClient()) {
    client.DefaultRequestHeaders.Clear();
    client.DefaultRequestHeaders.Add("X-API-Key", erpApiKey);
    client.DefaultRequestHeaders.Authorization = new AuthenticationHeaderValue("Bearer", oauthToken);
    
    // Request active customers limited to top 100 rows
    string endpoint = "https://server/SaaS/api/v2/odata/company/Erp.BO.CustomerSvc/Customers?$filter=Active eq true&$top=100";
    HttpResponseMessage response = await client.GetAsync(endpoint);
    
    if (response.IsSuccessStatusCode) {
        string jsonResult = await response.Content.ReadAsStringAsync();
        // Parse JSON customer record collection...
    }
}

By employing server-side filters and paging controls, we prevent network overhead and keep database transactions lightweight.