Add best practices and anti-patterns for Azure integration batching and error classification

custom/knowledge/integration/batch-outbound-work-only-when-the-remote-supports-it.bad.al

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+// Anti-pattern: "batching" by chaining single calls in one Job Queue run, and
+// a real batch with no per-item status. Both strand work on one failure.
+
+codeunit 50150 "WMS Sender (bad)"
+{
+    TableNo = "Job Queue Entry";
+
+    trigger OnRun()
+    var
+        IntegrationMessage: Record "Integration Message";
+        Client: HttpClient;
+        Request: HttpRequestMessage;
+        Response: HttpResponseMessage;
+    begin
+        IntegrationMessage.SetRange(Status, IntegrationMessage.Status::New);
+        if IntegrationMessage.FindSet() then
+            repeat
+                // BAD: fifty serial round trips inside one task. This is a wait
+                // loop with extra steps: one task and its locks are pinned for the
+                // whole sequence, and a slow remote slows every other queued job.
+                BuildRequest(IntegrationMessage, Request);
+                Client.Send(Request, Response);
+            until IntegrationMessage.Next() = 0;
+    end;
+
+    // BAD alternative: a genuine batch POST whose response is a single status.
+    procedure SendBlindBatch(var Request: HttpRequestMessage; Items: List of [Guid])
+    var
+        Client: HttpClient;
+        Response: HttpResponseMessage;
+        IntegrationMessage: Record "Integration Message";
+        Id: Guid;
+    begin
+        Client.Send(Request, Response);
+        // BAD: one IsSuccessStatusCode for the whole batch. One invalid item
+        // fails all fifty, and we cannot tell which item to fix or retry. A retry
+        // re-sends the items that already succeeded.
+        foreach Id in Items do begin
+            IntegrationMessage.Get(Id);
+            if Response.IsSuccessStatusCode() then
+                IntegrationMessage.Status := IntegrationMessage.Status::Resolved
+            else
+                IntegrationMessage.Status := IntegrationMessage.Status::Failed;
+            IntegrationMessage.Modify(true);
+        end;
+    end;
+}