Put/Write: Pass errors within client (not connected, ...) or from server

(no write access, other error reported by server) back up

Author: kasemir

core/pva/src/main/java/org/epics/pva/client/PutRequest.java

@@ -1,5 +1,5 @@
 /*******************************************************************************
- * Copyright (c) 2019-2020 Oak Ridge National Laboratory.
+ * Copyright (c) 2019-2022 Oak Ridge National Laboratory.
  * All rights reserved. This program and the accompanying materials
  * are made available under the terms of the Eclipse Public License v1.0
  * which accompanies this distribution, and is available at
@@ -153,7 +153,7 @@ public void handleResponse(final ByteBuffer buffer) throws Exception
         final byte subcmd = buffer.get();
         PVAStatus status = PVAStatus.decode(buffer);
         if (! status.isSuccess())
-            throw new Exception(channel + " Put Response for " + request + ": " + status);
+            fail(new Exception(channel + " Put Response for " + request + ": " + status));
 
         if (subcmd == PVAHeader.CMD_SUB_INIT)
         {
@@ -186,9 +186,15 @@ else if (subcmd == PVAHeader.CMD_SUB_DESTROY)
             complete(null);
         }
         else
-            throw new Exception("Cannot decode Put " + subcmd + " Reply #" + request_id);
+            fail(new Exception("Cannot decode Put " + subcmd + " Reply #" + request_id));
     }
 
+    /** Handle failure by both notifying whoever waits for this request to complete
+     *  and by throwing exception
+     *
+     *  @param ex Error description
+     *  @throws Exception
+     */
     private void fail(final Exception ex) throws Exception
     {
         completeExceptionally(ex);

core/pva/src/test/java/org/epics/pva/client/ClientDemo.java

@@ -1,5 +1,5 @@
 /*******************************************************************************
- * Copyright (c) 2019-2020 Oak Ridge National Laboratory.
+ * Copyright (c) 2019-2022 Oak Ridge National Laboratory.
  * All rights reserved. This program and the accompanying materials
  * are made available under the terms of the Eclipse Public License v1.0
  * which accompanies this distribution, and is available at
@@ -263,18 +263,39 @@ public void testStatic() throws Exception
         pva.close();
     }
 
+    /** Write ('put') test
+     * 
+     *  Includes a pause to allow manual stopping of the server.
+     *
+     *  May be used with read-only access security on IOC
+     *  to test failed write.
+     */
     @Test
     public void testPut() throws Exception
     {
         // Create a client
         final PVAClient pva = new PVAClient();
 
         // Connect to one or more channels
-        final PVAChannel channel = pva.getChannel("ramp");
+        final PVAChannel channel = pva.getChannel("saw");
         channel.connect().get(5, TimeUnit.SECONDS);
 
+
+        System.out.println("CONNECTED!");
+        System.out.println("Optionally stop the IOC within the next 10 seconds...");
+        TimeUnit.SECONDS.sleep(10);
+        System.out.println("Writing '2'...");
+
         // Write data
-        channel.write("value", 2.0).get(2, TimeUnit.SECONDS);
+        try
+        {
+            channel.write("value", 2.0).get(2, TimeUnit.SECONDS);
+        }
+        catch (Exception ex)
+        {
+            System.out.println("Write failed");
+            ex.printStackTrace();
+        }
 
         // Close channels
         channel.close();

core/pva/src/test/resources/demo.acf

@@ -0,0 +1,8 @@
+# Test read-only PVs:
+#
+# softIocPVA -m N='' -d demo.db -a demo.acf
+
+ASG(DEFAULT)
+{
+   RULE(1, READ)
+}