NIFI-4340 - fix record path evaluation when array is [ null ]

This closes #2122.

nifi-commons/nifi-record-path/src/main/java/org/apache/nifi/record/path/StandardFieldValue.java

@@ -122,6 +122,8 @@ public class StandardFieldValue implements FieldValue {
             if (value instanceof Record) {
                 ((Record) value).setValue(getField().getFieldName(), newValue);
                 return;
+            } else if (value == null) {
+                return; // value is null, nothing to update
             } else {
                 throw new UnsupportedOperationException("Cannot update the field value because the value is not associated with any record");
             }

nifi-commons/nifi-record-path/src/main/java/org/apache/nifi/record/path/paths/ChildFieldPath.java

@@ -47,6 +47,10 @@ public class ChildFieldPath extends RecordPathSegment {
         }
 
         final Record record = (Record) fieldValue.getValue();
+        if(record == null) {
+            return missingChild(fieldValue);
+        }
+
         final Object value = record.getValue(childName);
         if (value == null) {
             return missingChild(fieldValue);

nifi-nar-bundles/nifi-standard-bundle/nifi-standard-processors/pom.xml

@@ -498,11 +498,16 @@
                         <exclude>src/test/resources/TestExtractGrok/simple_text.log</exclude>
                         <exclude>src/test/resources/TestExtractGrok/patterns</exclude>
                         <exclude>src/test/resources/TestUpdateRecord/input/person.json</exclude>
+                        <exclude>src/test/resources/TestUpdateRecord/input/person-address.json</exclude>
+                        <exclude>src/test/resources/TestUpdateRecord/input/person-with-null-array.json</exclude>
+                        <exclude>src/test/resources/TestUpdateRecord/output/person-with-null-array.json</exclude>
                         <exclude>src/test/resources/TestUpdateRecord/output/person-with-firstname.json</exclude>
                         <exclude>src/test/resources/TestUpdateRecord/output/person-with-firstname-lastname.json</exclude>
                         <exclude>src/test/resources/TestUpdateRecord/output/person-with-capital-lastname.json</exclude>
                         <exclude>src/test/resources/TestUpdateRecord/output/name-fields-only.json</exclude>
                         <exclude>src/test/resources/TestUpdateRecord/output/name-and-mother-same.json</exclude>
+                        <exclude>src/test/resources/TestUpdateRecord/output/person-with-new-city.json</exclude>
+                        <exclude>src/test/resources/TestUpdateRecord/schema/person-with-address.avsc</exclude>
                         <exclude>src/test/resources/TestUpdateRecord/schema/person-with-name-record.avsc</exclude>
                         <exclude>src/test/resources/TestUpdateRecord/schema/person-with-name-string.avsc</exclude>
                         <exclude>src/test/resources/TestUpdateRecord/schema/person-with-name-string-fields.avsc</exclude>

nifi-nar-bundles/nifi-standard-bundle/nifi-standard-processors/src/test/java/org/apache/nifi/processors/standard/TestUpdateRecord.java

@@ -184,6 +184,66 @@ public class TestUpdateRecord {
         runner.getFlowFilesForRelationship(UpdateRecord.REL_SUCCESS).get(0).assertContentEquals(expectedOutput);
     }
 
+    @Test
+    public void testUpdateInArray() throws InitializationException, IOException {
+        final JsonTreeReader jsonReader = new JsonTreeReader();
+        runner.addControllerService("reader", jsonReader);
+
+        final String inputSchemaText = new String(Files.readAllBytes(Paths.get("src/test/resources/TestUpdateRecord/schema/person-with-address.avsc")));
+        final String outputSchemaText = new String(Files.readAllBytes(Paths.get("src/test/resources/TestUpdateRecord/schema/person-with-address.avsc")));
+
+        runner.setProperty(jsonReader, SchemaAccessUtils.SCHEMA_ACCESS_STRATEGY, SchemaAccessUtils.SCHEMA_TEXT_PROPERTY);
+        runner.setProperty(jsonReader, SchemaAccessUtils.SCHEMA_TEXT, inputSchemaText);
+        runner.enableControllerService(jsonReader);
+
+        final JsonRecordSetWriter jsonWriter = new JsonRecordSetWriter();
+        runner.addControllerService("writer", jsonWriter);
+        runner.setProperty(jsonWriter, SchemaAccessUtils.SCHEMA_ACCESS_STRATEGY, SchemaAccessUtils.SCHEMA_TEXT_PROPERTY);
+        runner.setProperty(jsonWriter, SchemaAccessUtils.SCHEMA_TEXT, outputSchemaText);
+        runner.setProperty(jsonWriter, "Pretty Print JSON", "true");
+        runner.setProperty(jsonWriter, "Schema Write Strategy", "full-schema-attribute");
+        runner.enableControllerService(jsonWriter);
+
+        runner.enqueue(Paths.get("src/test/resources/TestUpdateRecord/input/person-address.json"));
+        runner.setProperty("/address[*]/city", "newCity");
+        runner.setProperty(UpdateRecord.REPLACEMENT_VALUE_STRATEGY, UpdateRecord.LITERAL_VALUES);
+
+        runner.run();
+        runner.assertAllFlowFilesTransferred(UpdateRecord.REL_SUCCESS, 1);
+        final String expectedOutput = new String(Files.readAllBytes(Paths.get("src/test/resources/TestUpdateRecord/output/person-with-new-city.json")));
+        runner.getFlowFilesForRelationship(UpdateRecord.REL_SUCCESS).get(0).assertContentEquals(expectedOutput);
+    }
+
+    @Test
+    public void testUpdateInNullArray() throws InitializationException, IOException {
+        final JsonTreeReader jsonReader = new JsonTreeReader();
+        runner.addControllerService("reader", jsonReader);
+
+        final String inputSchemaText = new String(Files.readAllBytes(Paths.get("src/test/resources/TestUpdateRecord/schema/person-with-address.avsc")));
+        final String outputSchemaText = new String(Files.readAllBytes(Paths.get("src/test/resources/TestUpdateRecord/schema/person-with-address.avsc")));
+
+        runner.setProperty(jsonReader, SchemaAccessUtils.SCHEMA_ACCESS_STRATEGY, SchemaAccessUtils.SCHEMA_TEXT_PROPERTY);
+        runner.setProperty(jsonReader, SchemaAccessUtils.SCHEMA_TEXT, inputSchemaText);
+        runner.enableControllerService(jsonReader);
+
+        final JsonRecordSetWriter jsonWriter = new JsonRecordSetWriter();
+        runner.addControllerService("writer", jsonWriter);
+        runner.setProperty(jsonWriter, SchemaAccessUtils.SCHEMA_ACCESS_STRATEGY, SchemaAccessUtils.SCHEMA_TEXT_PROPERTY);
+        runner.setProperty(jsonWriter, SchemaAccessUtils.SCHEMA_TEXT, outputSchemaText);
+        runner.setProperty(jsonWriter, "Pretty Print JSON", "true");
+        runner.setProperty(jsonWriter, "Schema Write Strategy", "full-schema-attribute");
+        runner.enableControllerService(jsonWriter);
+
+        runner.enqueue(Paths.get("src/test/resources/TestUpdateRecord/input/person-with-null-array.json"));
+        runner.setProperty("/address[*]/city", "newCity");
+        runner.setProperty(UpdateRecord.REPLACEMENT_VALUE_STRATEGY, UpdateRecord.LITERAL_VALUES);
+
+        runner.run();
+        runner.assertAllFlowFilesTransferred(UpdateRecord.REL_SUCCESS, 1);
+        final String expectedOutput = new String(Files.readAllBytes(Paths.get("src/test/resources/TestUpdateRecord/output/person-with-null-array.json")));
+        runner.getFlowFilesForRelationship(UpdateRecord.REL_SUCCESS).get(0).assertContentEquals(expectedOutput);
+    }
+
     @Test
     public void testAddFieldNotInInputRecord() throws InitializationException, IOException {
         final JsonTreeReader jsonReader = new JsonTreeReader();

nifi-nar-bundles/nifi-standard-bundle/nifi-standard-processors/src/test/resources/TestUpdateRecord/input/person-address.json

@@ -0,0 +1,13 @@
+{
+	"id": 485,
+	"name": {
+		"last": "Doe",
+		"first": "John"
+	},
+	"address": [
+		{
+			"street": "1 nifi stree",
+			"city": "nifi"
+		}
+	]
+}

nifi-nar-bundles/nifi-standard-bundle/nifi-standard-processors/src/test/resources/TestUpdateRecord/input/person-with-null-array.json

@@ -0,0 +1,8 @@
+[ {
+  "id" : 485,
+  "name" : {
+    "last" : "Doe",
+    "first" : "John"
+  },
+  "address" : [ null ]
+} ]

nifi-nar-bundles/nifi-standard-bundle/nifi-standard-processors/src/test/resources/TestUpdateRecord/output/person-with-new-city.json

@@ -0,0 +1,11 @@
+[ {
+  "id" : 485,
+  "name" : {
+    "last" : "Doe",
+    "first" : "John"
+  },
+  "address" : [ {
+    "street" : "1 nifi stree",
+    "city" : "newCity"
+  } ]
+} ]

nifi-nar-bundles/nifi-standard-bundle/nifi-standard-processors/src/test/resources/TestUpdateRecord/output/person-with-null-array.json

@@ -0,0 +1,8 @@
+[ {
+  "id" : 485,
+  "name" : {
+    "last" : "Doe",
+    "first" : "John"
+  },
+  "address" : [ null ]
+} ]

nifi-nar-bundles/nifi-standard-bundle/nifi-standard-processors/src/test/resources/TestUpdateRecord/schema/person-with-address.avsc

@@ -0,0 +1,29 @@
+{
+	"name": "personWithNameRecord",
+	"namespace": "nifi",
+	"type": "record",
+	"fields": [
+		{ "name": "id", "type": "int" },
+		{ "name": "name", "type": {
+			"type": "record",
+			"name": "nameRecord",
+			"fields": [
+					{ "name": "last", "type": "string" },
+					{ "name": "first", "type": "string" }
+				]
+			}
+		},
+		{ "name" : "address", "type": ["null",
+										{ "type" : "array", "items" : {
+                              									"type" : "record",
+                              									"name" : "Person",
+                              									"fields" : [
+                              										{ "name" : "street", "type": "string" },
+                              										{ "name" : "city", "type": "string" }
+                              										]
+                              									}
+                              			}
+                              		]
+        }
+	]
+}