From 2bc60df11c0daa25c68a868342de823c348ed3c7 Mon Sep 17 00:00:00 2001
From: Marc Baloup <marc.baloup@laposte.net>
Date: Sun, 19 Mar 2023 17:25:14 +0100
Subject: [PATCH] Handle reception of ErrorPayload in WS.

---
 .../java/fr/pandacube/lib/ws/AbstractWS.java  | 36 ++++++++++++++-----
 .../fr/pandacube/lib/ws/PayloadRegistry.java  |  4 +--
 2 files changed, 30 insertions(+), 10 deletions(-)

diff --git a/pandalib-ws/src/main/java/fr/pandacube/lib/ws/AbstractWS.java b/pandalib-ws/src/main/java/fr/pandacube/lib/ws/AbstractWS.java
index 84888ff..4067d12 100644
--- a/pandalib-ws/src/main/java/fr/pandacube/lib/ws/AbstractWS.java
+++ b/pandalib-ws/src/main/java/fr/pandacube/lib/ws/AbstractWS.java
@@ -32,15 +32,26 @@ public interface AbstractWS {
             return;
         }
 
-        try {
-            onReceivePayload(payload);
-        } catch (Throwable t) {
-            trySendAsJson(new ErrorPayload("Error handling payload: " + t));
-            if (t instanceof Exception)
-                logError("Error handling payload", t);
-            else
-                throw t;
+        if (payload instanceof ErrorPayload errorPayload) {
+            try {
+                onReceiveErrorPayload(errorPayload);
+            } catch(Exception e) {
+                logError("Error while handling received error payload", e);
+            }
         }
+        else {
+            try {
+                onReceivePayload(payload);
+            } catch (Throwable t) {
+                trySendAsJson(new ErrorPayload("Error while handling your payload: " + t));
+                if (t instanceof Exception)
+                    logError("Error while handling received payload", t);
+                else
+                    throw t;
+            }
+        }
+
+
     }
 
     /**
@@ -62,6 +73,15 @@ public interface AbstractWS {
      */
     void onReceivePayload(Payload payload);
 
+    /**
+     * Called on reception of a valid {@link ErrorPayload}.
+     * @param error the received {@link ErrorPayload}.
+     * @implNote default implementation will log the received error.
+     */
+    default void onReceiveErrorPayload(ErrorPayload error) {
+        logError("Received the following error from the remote side: " + error.message, error.throwable);
+    }
+
     /**
      * Called on reception of a websocket Close packet.
      * The connection is closed after this method call.
diff --git a/pandalib-ws/src/main/java/fr/pandacube/lib/ws/PayloadRegistry.java b/pandalib-ws/src/main/java/fr/pandacube/lib/ws/PayloadRegistry.java
index ecf7a51..ad922a7 100644
--- a/pandalib-ws/src/main/java/fr/pandacube/lib/ws/PayloadRegistry.java
+++ b/pandalib-ws/src/main/java/fr/pandacube/lib/ws/PayloadRegistry.java
@@ -49,12 +49,12 @@ public class PayloadRegistry {
     public static Payload fromString(String message) {
         String[] split = message.split(Pattern.quote(PAYLOAD_TYPE_SEPARATOR), 2);
         if (split.length != 2) {
-            throw new IllegalArgumentException("Malformed message: does not respect format '<type>" + PAYLOAD_TYPE_SEPARATOR + "<jsonObject>'.");
+            throw new IllegalArgumentException("Malformed message: does not respect format ‘<type>" + PAYLOAD_TYPE_SEPARATOR + "<jsonObject>’.");
         }
 
         Class<? extends Payload> detectedClass = payloadClasses.get(split[0]);
         if (detectedClass == null) {
-            throw new IllegalArgumentException("Unrecognized data type '" + split[0] + "'.");
+            throw new IllegalArgumentException("Unrecognized data type ‘" + split[0] + "’.");
         }
 
         try {