1 files changed, 105 insertions, 0 deletions
diff --git a/sql/core/src/main/scala/org/apache/spark/sql/execution/command/functions.scala b/sql/core/src/main/scala/org/apache/spark/sql/execution/command/functions.scala
new file mode 100644
index 0000000000..c6e601799f
--- /dev/null
+++ b/sql/core/src/main/scala/org/apache/spark/sql/execution/command/functions.scala
@@ -0,0 +1,105 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.apache.spark.sql.execution.command
+
+import org.apache.spark.sql.{AnalysisException, Row, SQLContext}
+import org.apache.spark.sql.catalyst.FunctionIdentifier
+import org.apache.spark.sql.catalyst.catalog.CatalogFunction
+import org.apache.spark.sql.catalyst.expressions.ExpressionInfo
+
+
+/**
+ * The DDL command that creates a function.
+ * To create a temporary function, the syntax of using this command in SQL is:
+ * {{{
+ *    CREATE TEMPORARY FUNCTION functionName
+ *    AS className [USING JAR\FILE 'uri' [, JAR|FILE 'uri']]
+ * }}}
+ *
+ * To create a permanent function, the syntax in SQL is:
+ * {{{
+ *    CREATE FUNCTION [databaseName.]functionName
+ *    AS className [USING JAR\FILE 'uri' [, JAR|FILE 'uri']]
+ * }}}
+ */
+// TODO: Use Seq[FunctionResource] instead of Seq[(String, String)] for resources.
+case class CreateFunction(
+    databaseName: Option[String],
+    functionName: String,
+    className: String,
+    resources: Seq[(String, String)],
+    isTemp: Boolean)
+  extends RunnableCommand {
+
+  override def run(sqlContext: SQLContext): Seq[Row] = {
+    val catalog = sqlContext.sessionState.catalog
+    if (isTemp) {
+      if (databaseName.isDefined) {
+        throw new AnalysisException(
+          s"It is not allowed to provide database name when defining a temporary function. " +
+            s"However, database name ${databaseName.get} is provided.")
+      }
+      // We first load resources and then put the builder in the function registry.
+      // Please note that it is allowed to overwrite an existing temp function.
+      catalog.loadFunctionResources(resources)
+      val info = new ExpressionInfo(className, functionName)
+      val builder = catalog.makeFunctionBuilder(functionName, className)
+      catalog.createTempFunction(functionName, info, builder, ignoreIfExists = false)
+    } else {
+      // For a permanent, we will store the metadata into underlying external catalog.
+      // This function will be loaded into the FunctionRegistry when a query uses it.
+      // We do not load it into FunctionRegistry right now.
+      // TODO: should we also parse "IF NOT EXISTS"?
+      catalog.createFunction(
+        CatalogFunction(FunctionIdentifier(functionName, databaseName), className, resources),
+        ignoreIfExists = false)
+    }
+    Seq.empty[Row]
+  }
+}
+
+/**
+ * The DDL command that drops a function.
+ * ifExists: returns an error if the function doesn't exist, unless this is true.
+ * isTemp: indicates if it is a temporary function.
+ */
+case class DropFunction(
+    databaseName: Option[String],
+    functionName: String,
+    ifExists: Boolean,
+    isTemp: Boolean)
+  extends RunnableCommand {
+
+  override def run(sqlContext: SQLContext): Seq[Row] = {
+    val catalog = sqlContext.sessionState.catalog
+    if (isTemp) {
+      if (databaseName.isDefined) {
+        throw new AnalysisException(
+          s"It is not allowed to provide database name when dropping a temporary function. " +
+            s"However, database name ${databaseName.get} is provided.")
+      }
+      catalog.dropTempFunction(functionName, ifExists)
+    } else {
+      // We are dropping a permanent function.
+      catalog.dropFunction(
+        FunctionIdentifier(functionName, databaseName),
+        ignoreIfNotExists = ifExists)
+    }
+    Seq.empty[Row]
+  }
+}