[HUDI-2911] Removing default value for PARTITIONPATH_FIELD_NAME resulting in incorrect KeyGenerator configuration (#4195)

hudi-common/src/main/java/org/apache/hudi/exception/ExceptionUtil.java

@@ -0,0 +1,42 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you 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.apache.hudi.exception;
+
+import javax.annotation.Nonnull;
+
+/**
+ * Class collecting common utilities helping in handling {@link Exception}s
+ */
+public final class ExceptionUtil {
+  private ExceptionUtil() {}
+
+  /**
+   * Fetches inner-most cause of the provided {@link Throwable}
+   */
+  @Nonnull
+  public static Throwable getRootCause(@Nonnull Throwable t) {
+    Throwable cause = t;
+    while (cause.getCause() != null) {
+      cause = cause.getCause();
+    }
+
+    return cause;
+  }
+
+}

hudi-common/src/main/java/org/apache/hudi/keygen/constant/KeyGeneratorOptions.java

@@ -52,7 +52,7 @@ public class KeyGeneratorOptions extends HoodieConfig {
 
   public static final ConfigProperty<String> PARTITIONPATH_FIELD_NAME = ConfigProperty
       .key("hoodie.datasource.write.partitionpath.field")
-      .defaultValue("partitionpath")
+      .noDefaultValue()
       .withDocumentation("Partition path field. Value to be used at the partitionPath component of HoodieKey. "
           + "Actual value ontained by invoking .toString()");