fix: add support for ISO date/time format with offset in string to date converter (#3802)

* fix: add support for ISO date/time format in string to date converter

* fix: better test name

activiti-core/activiti-api-impl/activiti-api-process-model-impl/src/main/java/org/activiti/api/runtime/model/impl/StringToDateConverter.java

@@ -15,16 +15,29 @@
  */
 package org.activiti.api.runtime.model.impl;
 
-import java.time.Instant;
+import java.text.ParseException;
+import java.text.SimpleDateFormat;
+import java.time.format.DateTimeFormatter;
 import java.util.Date;
+import java.util.TimeZone;
 
 import org.springframework.core.convert.converter.Converter;
 
 @ProcessVariableTypeConverter
 public class StringToDateConverter implements Converter<String, Date> {
 
+    private static SimpleDateFormat ISO_DATE_TIME = new SimpleDateFormat("yyyy-MM-dd'T'HH:mm:ss.SSSXXX");
+
+    static {
+      ISO_DATE_TIME.setTimeZone(TimeZone.getTimeZone("UTC"));
+    }
+
     @Override
     public Date convert(String source) {
-        return Date.from(Instant.parse(source));
+        try {
+            return ISO_DATE_TIME.parse(source);
+        } catch (ParseException e) {
+            throw new RuntimeException(e);
+        }
     }
 }

activiti-core/activiti-api-impl/activiti-api-process-model-impl/src/test/java/org/activiti/api/runtime/model/impl/StringToDateConverterTest.java

+/*
+ * Copyright 2010-2020 Alfresco Software, Ltd.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.activiti.api.runtime.model.impl;
+
+import org.junit.jupiter.api.Test;
+
+import java.time.Instant;
+import java.util.Date;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+class StringToDateConverterTest {
+
+    private StringToDateConverter subject = new StringToDateConverter();
+
+    @Test
+    void convertISODateTimeUTC() {
+        //given
+        String source = "2022-01-17T00:00:00.000Z";
+
+        //when
+        Date result = subject.convert(source);
+
+        //then
+        assertThat(result).isEqualTo(Instant.parse(source));
+    }
+
+    @Test
+    void convertISODateTimeOffset() {
+        //given
+        String source = "2022-01-17T00:00:00.000-00:00";
+
+        //when
+        Date result = subject.convert(source);
+
+        //then
+        assertThat(result).isEqualTo(Date.from(Instant.parse("2022-01-17T00:00:00.000Z")));
+    }
+
+}