adds tests and guards against null values in some mutate methods

plugins/ingest/src/main/java/org/elasticsearch/ingest/processor/mutate/MutateProcessor.java

@@ -201,7 +201,9 @@ public final class MutateProcessor implements Processor {
     private void doSplit(Data data) {
         for(Map.Entry<String, String> entry : split.entrySet()) {
             Object oldVal = data.getProperty(entry.getKey());
-            if (oldVal instanceof String) {
+            if (oldVal == null) {
+                throw new IllegalArgumentException("Cannot split field. [" + entry.getKey() + "] is null.");
+            } else if (oldVal instanceof String) {
                 data.addField(entry.getKey(), Arrays.asList(((String) oldVal).split(entry.getValue())));
             } else {
                 throw new IllegalArgumentException("Cannot split a field that is not a String type");
@@ -247,7 +249,9 @@ public final class MutateProcessor implements Processor {
     private void doTrim(Data data) {
         for(String field : trim) {
             Object val = data.getProperty(field);
-            if (val instanceof String) {
+            if (val == null) {
+                throw new IllegalArgumentException("Cannot trim field. [" + field + "] is null.");
+            } else if (val instanceof String) {
                 data.addField(field, ((String) val).trim());
             } else {
                 throw new IllegalArgumentException("Cannot trim field:" + field + " with type: " + val.getClass());
@@ -258,7 +262,9 @@ public final class MutateProcessor implements Processor {
     private void doUppercase(Data data) {
         for(String field : uppercase) {
             Object val = data.getProperty(field);
-            if (val instanceof String) {
+            if (val == null) {
+                throw new IllegalArgumentException("Cannot uppercase field. [" + field + "] is null.");
+            } else if (val instanceof String) {
                 data.addField(field, ((String) val).toUpperCase(Locale.ROOT));
             } else {
                 throw new IllegalArgumentException("Cannot uppercase field:" + field + " with type: " + val.getClass());
@@ -269,7 +275,9 @@ public final class MutateProcessor implements Processor {
     private void doLowercase(Data data) {
         for(String field : lowercase) {
             Object val = data.getProperty(field);
-            if (val instanceof String) {
+            if (val == null) {
+                throw new IllegalArgumentException("Cannot lowercase field. [" + field + "] is null.");
+            } else if (val instanceof String) {
                 data.addField(field, ((String) val).toLowerCase(Locale.ROOT));
             } else {
                 throw new IllegalArgumentException("Cannot lowercase field:" + field + " with type: " + val.getClass());

plugins/ingest/src/test/java/org/elasticsearch/ingest/DataTests.java

@@ -28,6 +28,7 @@ import java.util.Map;
 
 import static org.hamcrest.Matchers.equalTo;
 import static org.hamcrest.Matchers.not;
+import static org.hamcrest.Matchers.nullValue;
 
 public class DataTests extends ESTestCase {
 
@@ -51,6 +52,11 @@ public class DataTests extends ESTestCase {
         assertThat(data.getProperty("fizz.buzz"), equalTo("hello world"));
     }
 
+    public void testGetPropertyNotFound() {
+        data.getProperty("not.here");
+        assertThat(data.getProperty("not.here"), nullValue());
+    }
+
     public void testContainsProperty() {
         assertTrue(data.containsProperty("fizz"));
     }

plugins/ingest/src/test/java/org/elasticsearch/ingest/processor/mutate/MutateProcessorTests.java

@@ -110,6 +110,18 @@ public class MutateProcessorTests extends ESTestCase {
         assertThat(data.getProperty("ip"), equalTo(Arrays.asList("127", "0", "0", "1")));
     }
 
+    public void testSplitNullValue() throws IOException {
+        Map<String, String> split = new HashMap<>();
+        split.put("not.found", "\\.");
+        Processor processor = new MutateProcessor(null, null, null, split, null, null, null, null, null, null);
+        try {
+            processor.execute(data);
+            fail();
+        } catch (IllegalArgumentException e) {
+            assertThat(e.getMessage(), equalTo("Cannot split field. [not.found] is null."));
+        }
+    }
+
     public void testGsub() throws IOException {
         List<GsubExpression> gsubExpressions = Collections.singletonList(new GsubExpression("ip", Pattern.compile("\\."), "-"));
         Processor processor = new MutateProcessor(null, null, null, null, gsubExpressions, null, null, null, null, null);
@@ -156,6 +168,17 @@ public class MutateProcessorTests extends ESTestCase {
         assertThat(data.getProperty("to_strip"), equalTo("clean"));
     }
 
+    public void testTrimNullValue() throws IOException {
+        List<String> trim = Collections.singletonList("not.found");
+        Processor processor = new MutateProcessor(null, null, null, null, null, null, null, trim, null, null);
+        try {
+            processor.execute(data);
+            fail();
+        } catch (IllegalArgumentException e) {
+            assertThat(e.getMessage(), equalTo("Cannot trim field. [not.found] is null."));
+        }
+    }
+
     public void testUppercase() throws IOException {
         List<String> uppercase = Collections.singletonList("foo");
         Processor processor = new MutateProcessor(null, null, null, null, null, null, null, null, uppercase, null);
@@ -164,6 +187,17 @@ public class MutateProcessorTests extends ESTestCase {
         assertThat(data.getProperty("foo"), equalTo("BAR"));
     }
 
+    public void testUppercaseNullValue() throws IOException {
+        List<String> uppercase = Collections.singletonList("not.found");
+        Processor processor = new MutateProcessor(null, null, null, null, null, null, null, null, uppercase, null);
+        try {
+            processor.execute(data);
+            fail();
+        } catch (IllegalArgumentException e) {
+            assertThat(e.getMessage(), equalTo("Cannot uppercase field. [not.found] is null."));
+        }
+    }
+
     public void testLowercase() throws IOException {
         List<String> lowercase = Collections.singletonList("alpha");
         Processor processor = new MutateProcessor(null, null, null, null, null, null, null, null, null, lowercase);
@@ -171,4 +205,15 @@ public class MutateProcessorTests extends ESTestCase {
         assertThat(data.getDocument().size(), equalTo(7));
         assertThat(data.getProperty("alpha"), equalTo("abcd"));
     }
+
+    public void testLowercaseNullValue() throws IOException {
+        List<String> lowercase = Collections.singletonList("not.found");
+        Processor processor = new MutateProcessor(null, null, null, null, null, null, null, null, null, lowercase);
+        try {
+            processor.execute(data);
+            fail();
+        } catch (IllegalArgumentException e) {
+            assertThat(e.getMessage(), equalTo("Cannot lowercase field. [not.found] is null."));
+        }
+    }
 }

plugins/ingest/src/test/resources/rest-api-spec/test/ingest/80_simulate.yaml

@@ -207,7 +207,7 @@
             ]
           }
   - length: { docs: 2 }
-  - match: { docs.0.error.type: "null_pointer_exception" }
+  - match: { docs.0.error.type: "illegal_argument_exception" }
   - is_true: docs.1.doc.modified
   - match: { docs.1.doc._source.foo: "BAR" }