Kinigopoulos opened a new issue #11267:
URL: https://github.com/apache/druid/issues/11267
Hello,
I am trying to make a new query type. I followed some of the other
extensions to get started with them but I had no luck. So I am asking what
should I do, to have a "boilerplate" extension query (Just return * from the
database).
**Extension loads successfully** but when I execute the query I get a
java.lang.NullPointerException error.
Specifically, according to the broker:
```
2021-05-18T01:56:04,595 WARN
[qtp1210856733-117[testQuery_[new-data-source]_queryId]]
org.apache.druid.server.QueryLifecycle - Exception while processing queryId
[queryId] (java.lang.NullPointerException: queryId)
2021-05-18T01:56:04,609 ERROR
[qtp1210856733-117[testQuery_[new-data-source]_queryId]]
org.apache.druid.server.QueryResource - Exception handling request:
{class=org.apache.druid.server.QueryResource, exceptionType=class
java.lang.NullPointerException, exceptionMessage=queryId,
query={"queryType":"testQuery","dataSource":{"type":"table","name":"new-data-source"},"intervals":{"type":"LegacySegmentSpec","intervals":["0000-01-01T00:00:00.000Z/3000-01-01T00:00:00.000Z"]},"context":{"queryId":"queryId"},"descending":false,"granularity":{"type":"all"}},
peer=127.0.0.1} (java.lang.NullPointerException: queryId)
```
### Affected Version
Tested on versions **0.21.0** and **0.20.1**
### Description
Configuration: micro-quickstart with the extension query loaded in the right
`_common` folder. Other configurations are untouched.
Java: 8 (openjdk 1.8.0_292)
Maven: 4.0.0
I am showing my code in case if I have done any silly mistake on my part:
##### TestQueryModule.java
```
public class TestQueryModule implements DruidModule {
public List<? extends Module> getJacksonModules() {
return ImmutableList.of(
new SimpleModule(getClass().getSimpleName())
.registerSubtypes(
new NamedType(TestQuery.class,
TestQuery.TEST_QUERY_TYPE)));
}
public void configure(Binder binder) {
DruidBinders.queryToolChestBinder(binder)
.addBinding(TestQuery.class)
.to(TestQueryQueryToolChest.class);
DruidBinders.queryRunnerFactoryBinder(binder)
.addBinding(TestQuery.class)
.to(TestQueryRunnerFactory.class);
}
}
```
##### TestQuery.java
```
public class TestQuery extends BaseQuery<Row> {
public static final String TEST_QUERY_TYPE = "testQuery";
@JsonCreator
public TestQuery(
@JsonProperty("dataSource") DataSource dataSource,
@JsonProperty("intervals") QuerySegmentSpec querySegmentSpec,
@JsonProperty("context") Map<String, Object> context
)
{
super(dataSource, querySegmentSpec, false, context);
}
public boolean hasFilters() {
return false;
}
public DimFilter getFilter() {
return null;
}
public String getType() {
return TEST_QUERY_TYPE;
}
public Query<Row> withOverriddenContext(Map<String, Object> map) {
return new TestQuery(getDataSource(), getQuerySegmentSpec(), map);
}
public Query<Row> withQuerySegmentSpec(QuerySegmentSpec
querySegmentSpec) {
return new TestQuery(getDataSource(), querySegmentSpec,
getContext());
}
public Query<Row> withDataSource(DataSource dataSource) {
return new TestQuery(dataSource, getQuerySegmentSpec(),
getContext());
}
}
```
##### TestQueryQueryToolChest.java
```
public class TestQueryQueryToolChest extends QueryToolChest<Row, TestQuery> {
public TestQueryQueryToolChest(){
System.out.println("TestQueryQueryToolChest created");
}
public QueryMetrics<? super TestQuery> makeMetrics(TestQuery testQuery) {
return new
DefaultGenericQueryMetricsFactory().makeMetrics(testQuery);
}
public Function<Row, Row> makePreComputeManipulatorFn(TestQuery
testQuery, MetricManipulationFn metricManipulationFn) {
return Functions.identity();
}
public TypeReference<Row> getResultTypeReference() {
return new TypeReference<Row>() {};
}
}
```
##### TestQueryRunnerFactory.java
```
public class TestQueryRunnerFactory implements QueryRunnerFactory<Row,
TestQuery> {
TestQueryQueryToolChest toolChest;
@Inject
public TestQueryRunnerFactory(TestQueryQueryToolChest toolChest){
System.out.println("TestQueryRunnerFactory created");
this.toolChest = toolChest;
}
public QueryRunner<Row> createRunner(Segment segment) {
System.out.println("Hello from runner factory: " + segment.getId());
return new QueryRunner<Row>() {
public Sequence<Row> run(QueryPlus<Row> queryPlus,
ResponseContext responseContext) {
return Sequences.empty();
}
};
}
public QueryRunner<Row> mergeRunners(ExecutorService executorService,
Iterable<QueryRunner<Row>> iterable) {
return new QueryRunner<Row>() {
public Sequence<Row> run(QueryPlus<Row> queryPlus,
ResponseContext responseContext) {
System.out.println("Hello from runner factory's merge
function");
return Sequences.empty();
}
};
}
public QueryToolChest<Row, TestQuery> getToolchest() {
return toolChest;
}
}
```
##### pom.xml
```
<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0";
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance";
xsi:schemaLocation="http://maven.apache.org/POM/4.0.0
http://maven.apache.org/xsd/maven-4.0.0.xsd";>
<modelVersion>4.0.0</modelVersion>
<groupId>org.example</groupId>
<artifactId>test-query</artifactId>
<version>1.0-SNAPSHOT</version>
<properties>
<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
<project.druid.version>0.21.0</project.druid.version>
</properties>
<dependencies>
<dependency>
<groupId>org.apache.druid</groupId>
<artifactId>druid-core</artifactId>
<version>${project.druid.version}</version>
<scope>provided</scope>
</dependency>
<dependency>
<groupId>org.apache.druid</groupId>
<artifactId>druid-processing</artifactId>
<version>${project.druid.version}</version>
<scope>provided</scope>
</dependency>
<dependency>
<groupId>org.apache.druid</groupId>
<artifactId>druid-server</artifactId>
<version>${project.druid.version}</version>
<scope>provided</scope>
</dependency>
</dependencies>
</project>
```
From some print outputs I've put in the classes it seems that
QueryRunnerFactory's methods don't execute (apart from the constructor).
Any help would be very much appreciated!
Thank you in advance!
--
This is an automated message from the Apache Git Service.
To respond to the message, please log on to GitHub and use the
URL above to go to the specific comment.
For queries about this service, please contact Infrastructure at:
[email protected]
---------------------------------------------------------------------
To unsubscribe, e-mail: [email protected]
For additional commands, e-mail: [email protected]
