better error messaging when parseSpec is missing timestampSpec or dimensionSpec (#5439)

api/src/main/java/io/druid/data/input/impl/ParseSpec.java

@@ -22,6 +22,7 @@ package io.druid.data.input.impl;
 import com.fasterxml.jackson.annotation.JsonProperty;
 import com.fasterxml.jackson.annotation.JsonSubTypes;
 import com.fasterxml.jackson.annotation.JsonTypeInfo;
+import com.google.common.base.Preconditions;
 import io.druid.guice.annotations.ExtensionPoint;
 import io.druid.guice.annotations.PublicApi;
 import io.druid.java.util.common.parsers.Parser;
@@ -47,8 +48,8 @@ public abstract class ParseSpec
 
   protected ParseSpec(TimestampSpec timestampSpec, DimensionsSpec dimensionsSpec)
   {
-    this.timestampSpec = timestampSpec;
-    this.dimensionsSpec = dimensionsSpec;
+    this.timestampSpec = Preconditions.checkNotNull(timestampSpec, "parseSpec requires timestampSpec");
+    this.dimensionsSpec = Preconditions.checkNotNull(dimensionsSpec, "parseSpec requires dimensionSpec");
   }
 
   @JsonProperty

api/src/test/java/io/druid/data/input/impl/ParseSpecTest.java

@@ -21,13 +21,18 @@ package io.druid.data.input.impl;
 
 import com.google.common.collect.Lists;
 import io.druid.java.util.common.parsers.ParseException;
+import org.junit.Rule;
 import org.junit.Test;
+import org.junit.rules.ExpectedException;
 
 import java.util.Arrays;
 import java.util.Collections;
 
 public class ParseSpecTest
 {
+  @Rule
+  public ExpectedException expectedException = ExpectedException.none();
+
   @Test(expected = ParseException.class)
   public void testDuplicateNames() throws Exception
   {
@@ -96,4 +101,46 @@ public class ParseSpecTest
         0
     );
   }
+
+  @Test
+  public void testDefaultTimestampSpec() throws Exception
+  {
+    expectedException.expect(NullPointerException.class);
+    expectedException.expectMessage("parseSpec requires timestampSpec");
+    @SuppressWarnings("unused") // expected exception
+    final ParseSpec spec = new DelimitedParseSpec(
+        null,
+        new DimensionsSpec(
+            DimensionsSpec.getDefaultSchemas(Collections.singletonList("a")),
+            Lists.newArrayList("B", "B"),
+            Lists.<SpatialDimensionSchema>newArrayList()
+        ),
+        ",",
+        null,
+        Arrays.asList("a", "B"),
+        false,
+        0
+    );
+  }
+
+  @Test
+  public void testDimensionSpecRequired() throws Exception
+  {
+    expectedException.expect(NullPointerException.class);
+    expectedException.expectMessage("parseSpec requires dimensionSpec");
+    @SuppressWarnings("unused") // expected exception
+    final ParseSpec spec = new DelimitedParseSpec(
+        new TimestampSpec(
+            "timestamp",
+            "auto",
+            null
+        ),
+        null,
+        ",",
+        null,
+        Arrays.asList("a", "B"),
+        false,
+        0
+    );
+  }
 }