Github user liancheng commented on a diff in the pull request:
https://github.com/apache/spark/pull/2590#discussion_r18215533
--- Diff:
sql/hive/src/main/scala/org/apache/spark/sql/hive/ExtendedHiveQlParser.scala ---
@@ -0,0 +1,138 @@
+/*
+ * 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.hive
+
+import scala.language.implicitConversions
+import scala.util.parsing.combinator.syntactical.StandardTokenParsers
+import scala.util.parsing.combinator.PackratParsers
+import scala.util.parsing.input.CharArrayReader.EofCh
+import org.apache.spark.sql.catalyst.plans.logical._
+import org.apache.spark.sql.catalyst.SqlLexical
+import scala.util.parsing.combinator.lexical.StdLexical
+
+/**
+ * A parser that recognizes all HiveQL constructs together with several
Spark SQL specific
+ * extensions like CACHE TABLE and UNCACHE TABLE.
+ */
+class ExtendedHiveQlParser extends StandardTokenParsers with
PackratParsers {
+
+ def apply(input: String): LogicalPlan = {
+ // Special-case out set commands since the value fields can be
+ // complex to handle without RegexParsers. Also this approach
+ // is clearer for the several possible cases of set commands.
+ if (input.trim.toLowerCase.startsWith("set")) {
+ input.trim.drop(3).split("=", 2).map(_.trim) match {
+ case Array("") => // "set"
+ SetCommand(None, None)
+ case Array(key) => // "set key"
+ SetCommand(Some(key), None)
+ case Array(key, value) => // "set key=value"
+ SetCommand(Some(key), Some(value))
+ }
+ } else if (input.trim.startsWith("!")) {
+ ShellCommand(input.drop(1))
+ } else {
+ phrase(query)(new lexical.Scanner(input)) match {
+ case Success(r, x) => r
+ case x => sys.error(x.toString)
+ }
+ }
+ }
+
+ protected case class Keyword(str: String)
+
+ protected val CACHE = Keyword("CACHE")
+ protected val SET = Keyword("SET")
+ protected val ADD = Keyword("ADD")
+ protected val JAR = Keyword("JAR")
+ protected val TABLE = Keyword("TABLE")
+ protected val AS = Keyword("AS")
+ protected val UNCACHE = Keyword("UNCACHE")
+ protected val FILE = Keyword("FILE")
+ protected val DFS = Keyword("DFS")
+ protected val SOURCE = Keyword("SOURCE")
+
+ protected implicit def asParser(k: Keyword): Parser[String] =
+ lexical.allCaseVersions(k.str).map(x => x : Parser[String]).reduce(_ |
_)
+
+ protected def allCaseConverse(k: String): Parser[String] =
+ lexical.allCaseVersions(k).map(x => x : Parser[String]).reduce(_ | _)
+
+ protected val reservedWords =
+ this.getClass
+ .getMethods
+ .filter(_.getReturnType == classOf[Keyword])
+ .map(_.invoke(this).asInstanceOf[Keyword].str)
+
+ override val lexical = new SqlLexical(reservedWords)
+
+ protected lazy val query: Parser[LogicalPlan] = (
+ cache | uncache | addJar | addFile | dfs | source | hiveQl
+ )
+
+ protected lazy val hiveQl: Parser[LogicalPlan] =
+ remainingQuery ^^ {
+ case r => HiveQl.createPlan(r.trim())
+ }
+
+ /** It returns all remaining query */
+ protected lazy val remainingQuery: Parser[String] = new Parser[String] {
+ def apply(in: Input) = Success(in.source.subSequence(in.offset,
in.source.length).toString,
+ in.drop(in.source.length()))
+ }
+
+ /** It returns all query */
+ protected lazy val allQuery: Parser[String] = new Parser[String] {
+ def apply(in: Input) = Success(in.source.toString,
+ in.drop(in.source.length()))
+ }
+
+ protected lazy val cache: Parser[LogicalPlan] =
+ CACHE ~ TABLE ~> ident ~ opt(AS ~> hiveQl) ^^ {
+ case tableName ~ None => CacheCommand(tableName, true)
+ case tableName ~ Some(plan) =>
+ CacheTableAsSelectCommand(tableName, plan)
+ }
+
+ protected lazy val uncache: Parser[LogicalPlan] =
+ UNCACHE ~ TABLE ~> ident ^^ {
+ case tableName => CacheCommand(tableName, false)
+ }
+
+ protected lazy val addJar: Parser[LogicalPlan] =
+ ADD ~ JAR ~> remainingQuery ^^ {
+ case rq => AddJar(rq.trim())
+ }
+
+ protected lazy val addFile: Parser[LogicalPlan] =
+ ADD ~ FILE ~> remainingQuery ^^ {
+ case rq => AddFile(rq.trim())
+ }
+
+ protected lazy val dfs: Parser[LogicalPlan] =
+ DFS ~> allQuery ^^ {
+ case aq => NativeCommand(aq.trim())
+ }
+
+ protected lazy val source: Parser[LogicalPlan] =
+ SOURCE ~> remainingQuery ^^ {
+ case rq => SourceCommand(rq.trim())
+ }
+
+}
--- End diff --
Noticed lots of trailing spaces in this file, please remove them.
---
If your project is set up for it, you can reply to this email and have your
reply appear on GitHub as well. If your project does not have this feature
enabled and wishes so, or if the feature is enabled but not working, please
contact infrastructure at infrastruct...@apache.org or file a JIRA ticket
with INFRA.
---
---------------------------------------------------------------------
To unsubscribe, e-mail: reviews-unsubscr...@spark.apache.org
For additional commands, e-mail: reviews-h...@spark.apache.org
