Add support for custom headers in HTTP requests

Enhanced HTTP request handling by adding support for dynamically including custom headers from the `request.Headers` collection. Implemented a null check to ensure robustness and prevent null reference exceptions when processing headers. This change improves flexibility and customization of HTTP requests.

src/ReC.Application/Common/Behaviors/BodyQueryBehavior.cs

@@ -9,12 +9,18 @@ public class BodyQueryBehavior<TRecAction>(IRecDbContext dbContext) : IPipelineB
     where TRecAction : RecActionDto
 {
     public async Task<Unit> Handle(TRecAction action, RequestHandlerDelegate<Unit> next, CancellationToken cancel)
-    {
+    {   
         if (action.BodyQuery is null)
             return await next(cancel);
-
+        
         var result = await dbContext.BodyQueryResults.FromSqlRaw(action.BodyQuery).FirstOrDefaultAsync(cancel);
-        action.Body = result?.RawBody;
+
+        if (result?.RawBody is null)
+            throw new InvalidOperationException(
+                $"Body query did not return a result or returned a null REQUEST_BODY. " +
+                $"ProfileId: {action.ProfileId}, ActionId: {action.ActionId}.");
+
+        action.Body = result.RawBody;
 
         return await next(cancel);
     }

src/ReC.Application/Common/Behaviors/HeaderQueryBehavior.cs

@@ -18,13 +18,24 @@ public class HeaderQueryBehavior<TRecAction>(IRecDbContext dbContext, ILogger<He
         var result = await dbContext.HeaderQueryResults.FromSqlRaw(action.HeaderQuery).FirstOrDefaultAsync(cancel);
 
         if(result?.RawHeader is null)
+        {
+            logger?.LogWarning("Header query did not return a result or returned a null REQUEST_HEADER. Profile ID: {ProfileId}, Action ID: {ActionId}", action.ProfileId, action.ActionId);
+
+            action.IsReturnedNoData.HeaderQuery = true;
+
             return await next(cancel);
+        }
 
         var headerDict = JsonSerializer.Deserialize<Dictionary<string, JsonElement>>(result.RawHeader);
 
         if(headerDict is null)
         {
-            logger?.LogWarning("Failed to deserialize header query result: {RawHeader}. Profile ID: {ProfileId}, Action ID: {ActionId}", result.RawHeader, action.ProfileId, action.ActionId);
+            logger?.LogWarning(
+                "Header JSON deserialization returned null. RawHeader: {RawHeader}, ProfileId: {ProfileId}, ActionId: {ActionId}",
+                result.RawHeader, action.ProfileId, action.ActionId);
+
+            action.IsReturnedNoData.HeaderQuery = true;
+
             return await next(cancel);
         }
 

src/ReC.Application/Common/Dto/RecActionDto.cs

@@ -60,6 +60,8 @@ public record RecActionDto
 
     public string? Body { get; set; }
 
+    public (bool BodyQuery, bool HeaderQuery) IsReturnedNoData = (false, false);
+
     public string? PostprocessingQuery { get; init; }
 
     public UriBuilder ToEndpointUriBuilder()

src/ReC.Application/RecActions/Commands/InvokeRecActionCommand.cs

@@ -40,6 +40,27 @@ public class InvokeRecActionCommandHandler(
             .ToHttpMethod()
             .ToHttpRequestMessage(request.EndpointUri);
 
+        if(request.Body is not null)
+        {
+            using var reqBody = new StringContent(request.Body);
+            httpReq.Content = reqBody;
+        }
+        else if(request.BodyQuery is not null && !request.IsReturnedNoData.BodyQuery)
+        {
+            logger?.LogWarning(
+               "Although BodyQuery returns null, the IsReturnedNoData variable has not been set to TRUE. " +
+               "This indicates that BodyQueryBehavior has not been executed or that the relevant control step has been skipped. " +
+               "The relevant behavior must be verified to ensure that the process does not produce unexpected conditions. " +
+               "ProfileId: {ProfileId}, ActionId: {ActionId}",
+               request.ProfileId,
+               request.ActionId
+            );
+        }
+
+        if (request.Headers is not null)
+            foreach (var header in request.Headers)
+                httpReq.Headers.Add(header.Key, header.Value);
+
         using var response = await http.SendAsync(httpReq, cancel);
         var body = await response.Content.ReadAsStringAsync(cancel);
         var headers = response.Headers.ToDictionary();