Avoid Public Event publisher

community/knowledge/events/declare-event-publishers-local-or-internal.bad.al

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+// Demonstration only. Shows the wrong pattern: the publisher carries no access modifier, so it is
+// public - which never was what lets extensions subscribe.
+
+codeunit 50100 "Loyalty Points Mgt Bad"
+{
+    procedure AwardPoints(CustomerNo: Code[20]; SalesAmount: Decimal)
+    var
+        Points: Decimal;
+        IsHandled: Boolean;
+    begin
+        Points := SalesAmount / 10;
+
+        IsHandled := false;
+        OnBeforeAwardPoints(CustomerNo, Points, IsHandled);
+        if IsHandled then
+            exit;
+
+        // ... insert the loyalty entry ...
+    end;
+
+    // BAD: no access modifier, so this publisher is public. Public access does not enable
+    // subscription - it enables raising. Narrowing it to internal after release breaks callers,
+    // so the widening cannot be walked back cheaply.
+    [IntegrationEvent(false, false)]
+    procedure OnBeforeAwardPoints(CustomerNo: Code[20]; var Points: Decimal; var IsHandled: Boolean)
+    begin
+    end;
+}
+
+codeunit 50101 "Loyalty Points Caller Bad"
+{
+    procedure FirePublisherDirectly(CustomerNo: Code[20])
+    var
+        LoyaltyPointsMgt: Codeunit "Loyalty Points Mgt Bad";
+        Points: Decimal;
+        IsHandled: Boolean;
+    begin
+        // Compiles only because the publisher is public. Every subscriber runs although no points
+        // were ever awarded, on a Points value nobody computed, and the IsHandled answer the
+        // subscribers write is read by no one.
+        LoyaltyPointsMgt.OnBeforeAwardPoints(CustomerNo, Points, IsHandled);
+    end;
+}