Refactor file attachment handling: update documentation for file download endpoint; improve response descriptions; correct max file attachment size in configuration files.

Author: mm-omdi

source/AAS.TwinEngine.DataEngine/Api/SubmodelRepository/SubmodelRepositoryController.cs

@@ -153,14 +153,13 @@ public async Task<ActionResult<JsonObject>> GetSubmodelElementAsync([FromRoute]
     }
 
     /// <summary>
-    /// Downloads the binary file content of a File SubmodelElement.
-    /// The Content-Type header is derived from the element's contentType attribute.
+    /// Downloads file content from a specific submodel element from the Submodel at a specified path.
     /// </summary>
     /// <param name="submodelIdentifier">The Submodel's unique id (UTF8-BASE64-URL-encoded)</param>
     /// <param name="idShortPath">The IdShort path to the File SubmodelElement (dot-separated)</param>
-    /// <response code="200">Binary file content streamed from the plugin.</response>
-    /// <response code="400">The element at idShortPath is not a File SubmodelElement, or the request is malformed.</response>
-    /// <response code="404">Submodel or element not found.</response>
+    /// <response code="200">Requested File.</response>
+    /// <response code="400">Bad Request, e.g. the request parameters of the format of the request body is wrong.</response>
+    /// <response code="404">Not Found</response>
     /// <response code="500">Internal Server Error</response>
     [HttpGet("{submodelIdentifier}/submodel-elements/{idShortPath}/attachment")]
     [ProducesResponseType(typeof(FileResult), (int)HttpStatusCode.OK)]

source/AAS.TwinEngine.DataEngine/ServiceConfiguration/Config/GeneralConfig.cs

@@ -17,7 +17,7 @@ public class GeneralConfig
     public OpenTelemetrySettings OpenTelemetry { get; set; } = new();
     public CacheConfig Cache { get; set; } = new();
 
-    public long MaxFileAttachmentSizeBytes { get; set; } = 100 * 1024 * 1024; // 100 MB
+    public long MaxFileAttachmentSizeBytes { get; set; } = 104857600; // 100 MB
 
     /// <summary>
     /// Domain URL of the customer environment (V2: direct property; V1: was AasEnvironment:CustomerDomainUrl).

source/AAS.TwinEngine.DataEngine/appsettings.development.json

@@ -17,7 +17,7 @@
       },
       "BlockedPatterns": ["\\r|\\n", "\\x00", "<script"]
     },
-    "MaxFileAttachmentSizeBytes": 204857600,
+    "MaxFileAttachmentSizeBytes": 104857600,
     "AllowedHosts": "*",
     "OpenTelemetry": {
       "OtlpEndpoint": "http://localhost:4317",