Tested and fixed ModbusSerializationCatcher

client/src/main/java/me/retrodaredevil/solarthing/program/check/ModbusSerializationCatcher.java

@@ -23,10 +23,21 @@ public ModbusSerializationCatcher(BeanPropertyWriter base) {
 	@Override
 	public void serializeAsField(Object bean, JsonGenerator gen, SerializerProvider prov) throws Exception {
 		try {
+			System.out.println("Serializing: " + _name);
 			super.serializeAsField(bean, gen, prov);
-		} catch (ErrorCodeException ex) {
+		} catch (Exception ex) { // likely an InvocationTargetException, but catch exception in case it is anything else
+			final ErrorCodeException actual;
+			if (ex instanceof ErrorCodeException) {
+				actual = (ErrorCodeException) ex;
+			} else {
+				if (ex.getCause() instanceof ErrorCodeException) {
+					actual = (ErrorCodeException) ex.getCause();
+				} else {
+					throw ex;
+				}
+			}
 			gen.writeFieldName(_name);
-			gen.writeString("Modbus Exception: " + ex.getExceptionCode());
+			gen.writeString("Modbus Exception: " + actual.getExceptionCode());
 		}
 	}
 

client/src/test/java/me/retrodaredevil/solarthing/program/check/ModbusSerializationCatcherTest.java

@@ -0,0 +1,33 @@
+package me.retrodaredevil.solarthing.program.check;
+
+import com.fasterxml.jackson.annotation.JsonProperty;
+import com.fasterxml.jackson.core.JsonProcessingException;
+import com.fasterxml.jackson.databind.ObjectMapper;
+import me.retrodaredevil.io.modbus.ModbusMessages;
+import me.retrodaredevil.io.modbus.handling.ErrorCodeException;
+import me.retrodaredevil.solarthing.util.JacksonUtil;
+import org.junit.jupiter.api.Test;
+
+import static org.junit.jupiter.api.Assertions.*;
+
+class ModbusSerializationCatcherTest {
+
+	@Test
+	void test() throws JsonProcessingException {
+		ObjectMapper modbusCatchingMapper = JacksonUtil.defaultMapper();
+		modbusCatchingMapper.registerModule(ModbusSerializationCatcher.createModule(TestObject.class));
+		assertEquals("{\"test1\":5,\"test2\":5,\"test3\":\"Modbus Exception: 2\"}", modbusCatchingMapper.writeValueAsString(new TestObject()));
+	}
+
+	private static class TestObject {
+		@JsonProperty
+		private int test1 = 5;
+		@JsonProperty
+		private int test2 = 5;
+
+		@JsonProperty
+		private int getTest3() {
+			throw new ErrorCodeException(ModbusMessages.createMessage(131, new int[0]), 3, 2);
+		}
+	}
+}