HeaderParameters

Namespace: RA.Utilities.Core.Constants

The HeaderParameters class acts as a central repository for common HTTP header names used throughout your services. It is part of the RA.Utilities.Core.Constants package.

Its purpose is to eliminate "magic strings" from your code. Instead of hard-coding header names like "x-request-id" or "Authorization" directly in your middleware, API endpoints, or HTTP clients, you use a named read-only field like HeaderParameters.XRequestId.

This simple practice provides several key benefits:

Readability: The code becomes more self-documenting and easier to understand. Request.Headers[HeaderParameters.XRequestId] is much clearer than Request.Headers["x-request-id"].
Consistency: It guarantees that every part of your application ecosystem uses the exact same string for a given header, preventing subtle inconsistencies.
Maintainability: If you ever need to change a header name (e.g., for compliance with a new standard), you only need to update it in this one central file.
Reduced Errors: It prevents typos in string literals, which can lead to bugs that are often difficult to track down.

This class is used across the RA.Utilities packages — for example, by DefaultHeadersMiddleware and the Integrations delegating handlers to read or write correlation IDs and authorization tokens, and by the OpenAPI HeadersParameterTransformer to document headers.

Read-only, not const: Since v10.0.4 these fields are static readonly, not compile-time constants. Read them directly at runtime, but do not use them where C# requires a constant expression — attribute arguments, default parameter values, case labels, or const declarations. See the migration guide for replacements.

Values

Field Name	Value	Description
XRequestId	`"x-request-id"`	Used for request correlation and tracing.
TraceId	`"trace-id"`	Used for internal tracing, often associated with a distributed trace.
Location	`"location"`	Used in `201 Created` responses to point to the new resource's URL.
Authorization	`"Authorization"`	Used for sending authentication credentials (e.g., a Bearer token).

Header lookups are case-insensitive. HTTP header names compare case-insensitively, so HeaderParameters.Location ("location") and HeaderParameters.Authorization ("Authorization") both work regardless of casing. The constants preserve the casing the ecosystem emits on the wire.

using Microsoft.AspNetCore.Mvc;
using RA.Utilities.Core.Constants;

[ApiController]
[Route("api/[controller]")]
public class ExampleController : ControllerBase
{
    [HttpGet("{id}")]
    public IActionResult GetProduct(int id)
    {
        return Ok(product);
    }

    [HttpGet("whoami")]
    public IActionResult GetUserFromHeader()
    {
        // Use a named value to safely access a header
        if (Request.Headers.TryGetValue(HeaderParameters.Authorization, out var authHeader))
        {
            // Logic to parse the token...
            return Ok($"Authorization header found: {authHeader}");
        }

        return Unauthorized(BaseResponseMessages.Unauthorized);
    }
}

Values​

Values