Introduce reusable QL plugin for SQL and EQL (elastic#50815)

Extract reusable functionality from SQL into its own dedicated project QL.
Implemented as a plugin, it provides common components across SQL and the upcoming EQL.

While this commit is fairly large, for the most part it's just a big file move from sql package to the newly introduced ql.

x-pack/plugin/ql/build.gradle

@@ -0,0 +1,36 @@
+evaluationDependsOn(xpackModule('core'))
+
+apply plugin: 'elasticsearch.esplugin'
+esplugin {
+  name 'x-pack-ql'
+  description 'Elasticsearch infrastructure plugin for EQL and SQL for Elasticsearch'
+  classname 'org.elasticsearch.xpack.ql.plugin.QlPlugin'
+  extendedPlugins = ['x-pack-core']
+}
+
+archivesBaseName = 'x-pack-ql'
+
+dependencies {
+  compileOnly project(path: xpackModule('core'), configuration: 'default')
+  testCompile project(':test:framework')
+  testCompile project(path: xpackModule('core'), configuration: 'testArtifacts')
+}
+
+configurations {
+  testArtifacts.extendsFrom testRuntime
+}
+
+task testJar(type: Jar) {
+  appendix 'test'
+  from sourceSets.test.output
+}
+
+artifacts {
+  // normal es plugins do not publish the jar but we need to since users need it for extensions
+  archives jar
+  testArtifacts testJar
+}
+
+
+// disable integration tests for now
+integTest.enabled = false

x-pack/plugin/ql/src/main/java/org/elasticsearch/xpack/ql/ParsingException.java

@@ -0,0 +1,61 @@
+/*
+ * Copyright Elasticsearch B.V. and/or licensed to Elasticsearch B.V. under one
+ * or more contributor license agreements. Licensed under the Elastic License;
+ * you may not use this file except in compliance with the Elastic License.
+ */
+
+package org.elasticsearch.xpack.ql;
+
+import org.elasticsearch.rest.RestStatus;
+import org.elasticsearch.xpack.ql.tree.Source;
+
+import static org.elasticsearch.common.logging.LoggerMessageFormat.format;
+
+public class ParsingException extends QlClientException {
+    private final int line;
+    private final int charPositionInLine;
+
+    public ParsingException(String message, Exception cause, int line, int charPositionInLine) {
+        super(message, cause);
+        this.line = line;
+        this.charPositionInLine = charPositionInLine;
+    }
+
+    public ParsingException(String message, Object... args) {
+        this(Source.EMPTY, message, args);
+    }
+
+    public ParsingException(Source source, String message, Object... args) {
+        super(message, args);
+        this.line = source.source().getLineNumber();
+        this.charPositionInLine = source.source().getColumnNumber();
+    }
+
+    public ParsingException(Exception cause, Source source, String message, Object... args) {
+        super(cause, message, args);
+        this.line = source.source().getLineNumber();
+        this.charPositionInLine = source.source().getColumnNumber();
+    }
+
+    public int getLineNumber() {
+        return line;
+    }
+
+    public int getColumnNumber() {
+        return charPositionInLine + 1;
+    }
+
+    public String getErrorMessage() {
+        return super.getMessage();
+    }
+
+    @Override
+    public RestStatus status() {
+        return RestStatus.BAD_REQUEST;
+    }
+
+    @Override
+    public String getMessage() {
+        return format("line {}:{}: {}", getLineNumber(), getColumnNumber(), getErrorMessage());
+    }
+}

x-pack/plugin/ql/src/main/java/org/elasticsearch/xpack/ql/QlClientException.java

@@ -0,0 +1,29 @@
+/*
+ * Copyright Elasticsearch B.V. and/or licensed to Elasticsearch B.V. under one
+ * or more contributor license agreements. Licensed under the Elastic License;
+ * you may not use this file except in compliance with the Elastic License.
+ */
+package org.elasticsearch.xpack.ql;
+
+public abstract class QlClientException extends QlException {
+
+    protected QlClientException(String message, Object... args) {
+        super(message, args);
+    }
+
+    protected QlClientException(String message, Throwable cause, boolean enableSuppression, boolean writableStackTrace) {
+        super(message, cause, enableSuppression, writableStackTrace);
+    }
+
+    protected QlClientException(String message, Throwable cause) {
+        super(message, cause);
+    }
+
+    protected QlClientException(Throwable cause, String message, Object... args) {
+        super(cause, message, args);
+    }
+
+    protected QlClientException(Throwable cause) {
+        super(cause);
+    }
+}

x-pack/plugin/sql/src/main/java/org/elasticsearch/xpack/sql/SqlException.java → x-pack/plugin/ql/src/main/java/org/elasticsearch/xpack/ql/QlException.java

@@ -3,28 +3,28 @@
  * or more contributor license agreements. Licensed under the Elastic License;
  * you may not use this file except in compliance with the Elastic License.
  */
-package org.elasticsearch.xpack.sql;
+package org.elasticsearch.xpack.ql;
 
 import org.elasticsearch.ElasticsearchException;
 
-public abstract class SqlException extends ElasticsearchException {
-    public SqlException(String message, Throwable cause, boolean enableSuppression, boolean writableStackTrace) {
+public abstract class QlException extends ElasticsearchException {
+    public QlException(String message, Throwable cause, boolean enableSuppression, boolean writableStackTrace) {
         super(message, cause, enableSuppression, writableStackTrace);
     }
 
-    public SqlException(String message, Throwable cause) {
+    public QlException(String message, Throwable cause) {
         super(message, cause);
     }
 
-    public SqlException(String message, Object... args) {
+    public QlException(String message, Object... args) {
         super(message, args);
     }
 
-    public SqlException(Throwable cause, String message, Object... args) {
+    public QlException(Throwable cause, String message, Object... args) {
         super(message, cause, args);
     }
 
-    public SqlException(Throwable cause) {
+    public QlException(Throwable cause) {
         super(cause);
     }
 }

x-pack/plugin/ql/src/main/java/org/elasticsearch/xpack/ql/QlIllegalArgumentException.java

@@ -0,0 +1,32 @@
+/*
+ * Copyright Elasticsearch B.V. and/or licensed to Elasticsearch B.V. under one
+ * or more contributor license agreements. Licensed under the Elastic License;
+ * you may not use this file except in compliance with the Elastic License.
+ */
+package org.elasticsearch.xpack.ql;
+
+public class QlIllegalArgumentException extends QlServerException {
+    public QlIllegalArgumentException(String message, Throwable cause, boolean enableSuppression, boolean writableStackTrace) {
+        super(message, cause, enableSuppression, writableStackTrace);
+    }
+
+    public QlIllegalArgumentException(String message, Throwable cause) {
+        super(message, cause);
+    }
+
+    public QlIllegalArgumentException(String message, Object... args) {
+        super(message, args);
+    }
+
+    public QlIllegalArgumentException(Throwable cause, String message, Object... args) {
+        super(cause, message, args);
+    }
+
+    public QlIllegalArgumentException(String message) {
+        super(message);
+    }
+
+    public QlIllegalArgumentException(Throwable cause) {
+        super(cause);
+    }
+}

x-pack/plugin/ql/src/main/java/org/elasticsearch/xpack/ql/QlServerException.java

@@ -0,0 +1,29 @@
+/*
+ * Copyright Elasticsearch B.V. and/or licensed to Elasticsearch B.V. under one
+ * or more contributor license agreements. Licensed under the Elastic License;
+ * you may not use this file except in compliance with the Elastic License.
+ */
+package org.elasticsearch.xpack.ql;
+
+public abstract class QlServerException extends QlException {
+
+    protected QlServerException(String message, Object... args) {
+        super(message, args);
+    }
+
+    protected QlServerException(String message, Throwable cause, boolean enableSuppression, boolean writableStackTrace) {
+        super(message, cause, enableSuppression, writableStackTrace);
+    }
+
+    protected QlServerException(String message, Throwable cause) {
+        super(message, cause);
+    }
+
+    protected QlServerException(Throwable cause, String message, Object... args) {
+        super(cause, message, args);
+    }
+
+    protected QlServerException(Throwable cause) {
+        super(cause);
+    }
+}

x-pack/plugin/sql/src/main/java/org/elasticsearch/xpack/sql/capabilities/Resolvable.java → x-pack/plugin/ql/src/main/java/org/elasticsearch/xpack/ql/capabilities/Resolvable.java

@@ -3,7 +3,7 @@
  * or more contributor license agreements. Licensed under the Elastic License;
  * you may not use this file except in compliance with the Elastic License.
  */
-package org.elasticsearch.xpack.sql.capabilities;
+package org.elasticsearch.xpack.ql.capabilities;
 
 public interface Resolvable {
 

x-pack/plugin/sql/src/main/java/org/elasticsearch/xpack/sql/capabilities/Resolvables.java → x-pack/plugin/ql/src/main/java/org/elasticsearch/xpack/ql/capabilities/Resolvables.java

@@ -3,7 +3,7 @@
  * or more contributor license agreements. Licensed under the Elastic License;
  * you may not use this file except in compliance with the Elastic License.
  */
-package org.elasticsearch.xpack.sql.capabilities;
+package org.elasticsearch.xpack.ql.capabilities;
 
 public abstract class Resolvables {
 

x-pack/plugin/sql/src/main/java/org/elasticsearch/xpack/sql/capabilities/Unresolvable.java → x-pack/plugin/ql/src/main/java/org/elasticsearch/xpack/ql/capabilities/Unresolvable.java

@@ -3,7 +3,7 @@
  * or more contributor license agreements. Licensed under the Elastic License;
  * you may not use this file except in compliance with the Elastic License.
  */
-package org.elasticsearch.xpack.sql.capabilities;
+package org.elasticsearch.xpack.ql.capabilities;
 
 
 public interface Unresolvable extends Resolvable {

x-pack/plugin/sql/src/main/java/org/elasticsearch/xpack/sql/capabilities/UnresolvedException.java → x-pack/plugin/ql/src/main/java/org/elasticsearch/xpack/ql/capabilities/UnresolvedException.java

@@ -3,15 +3,15 @@
  * or more contributor license agreements. Licensed under the Elastic License;
  * you may not use this file except in compliance with the Elastic License.
  */
-package org.elasticsearch.xpack.sql.capabilities;
+package org.elasticsearch.xpack.ql.capabilities;
 
-import org.elasticsearch.xpack.sql.ServerSqlException;
+import org.elasticsearch.xpack.ql.QlServerException;
 
 /**
  * Thrown when we accidentally attempt to resolve something on on an unresolved entity. Throwing this
  * is always a bug.
  */
-public class UnresolvedException extends ServerSqlException {
+public class UnresolvedException extends QlServerException {
     public UnresolvedException(String action, Object target) {
         super("Invalid call to {} on an unresolved object {}", action, target);
     }

x-pack/plugin/sql/src/main/java/org/elasticsearch/xpack/sql/execution/search/AggRef.java → x-pack/plugin/ql/src/main/java/org/elasticsearch/xpack/ql/execution/search/AggRef.java

@@ -3,15 +3,15 @@
  * or more contributor license agreements. Licensed under the Elastic License;
  * you may not use this file except in compliance with the Elastic License.
  */
-package org.elasticsearch.xpack.sql.execution.search;
+package org.elasticsearch.xpack.ql.execution.search;
 
 /**
  * Reference to a ES aggregation (which can be either a GROUP BY or Metric agg).
  */
 public abstract class AggRef implements FieldExtraction {
 
     @Override
-    public void collectFields(SqlSourceBuilder sourceBuilder) {
+    public void collectFields(QlSourceBuilder sourceBuilder) {
         // Aggregations do not need any special fields
     }
 

x-pack/plugin/sql/src/main/java/org/elasticsearch/xpack/sql/execution/search/FieldExtraction.java → x-pack/plugin/ql/src/main/java/org/elasticsearch/xpack/ql/execution/search/FieldExtraction.java

@@ -3,7 +3,7 @@
  * or more contributor license agreements. Licensed under the Elastic License;
  * you may not use this file except in compliance with the Elastic License.
  */
-package org.elasticsearch.xpack.sql.execution.search;
+package org.elasticsearch.xpack.ql.execution.search;
 
 import org.elasticsearch.search.builder.SearchSourceBuilder;
 
@@ -17,7 +17,7 @@ public interface FieldExtraction {
      * in order to fetch the field. This can include tracking the score,
      * {@code _source} fields, doc values fields, and script fields.
      */
-    void collectFields(SqlSourceBuilder sourceBuilder);
+    void collectFields(QlSourceBuilder sourceBuilder);
 
     /**
      * Is this aggregation supported in an "aggregation only" query

x-pack/plugin/sql/src/main/java/org/elasticsearch/xpack/sql/execution/search/SqlSourceBuilder.java → x-pack/plugin/ql/src/main/java/org/elasticsearch/xpack/ql/execution/search/QlSourceBuilder.java

@@ -3,7 +3,7 @@
  * or more contributor license agreements. Licensed under the Elastic License;
  * you may not use this file except in compliance with the Elastic License.
  */
-package org.elasticsearch.xpack.sql.execution.search;
+package org.elasticsearch.xpack.ql.execution.search;
 
 import org.elasticsearch.common.Strings;
 import org.elasticsearch.script.Script;
@@ -20,15 +20,15 @@
  * {@link FieldExtraction} that can "build" whatever needs to be extracted from
  * the resulting ES document as a field.
  */
-public class SqlSourceBuilder {
+public class QlSourceBuilder {
     // The LinkedHashMaps preserve the order of the fields in the response
-    final Set<String> sourceFields = new LinkedHashSet<>();
-    final Set<FieldAndFormat> docFields = new LinkedHashSet<>();
-    final Map<String, Script> scriptFields = new LinkedHashMap<>();
+    private final Set<String> sourceFields = new LinkedHashSet<>();
+    private final Set<FieldAndFormat> docFields = new LinkedHashSet<>();
+    private final Map<String, Script> scriptFields = new LinkedHashMap<>();
 
     boolean trackScores = false;
 
-    public SqlSourceBuilder() {
+    public QlSourceBuilder() {
     }
 
     /**
@@ -71,4 +71,8 @@ public void build(SearchSourceBuilder sourceBuilder) {
         docFields.forEach(field -> sourceBuilder.docValueField(field.field, field.format));
         scriptFields.forEach(sourceBuilder::scriptField);
     }
+
+    public boolean noSource() {
+        return sourceFields.isEmpty();
+    }
 }