Merge pull request #1543 from loxp/antlr-parser

add ANTLR PostgreSQL DAL parser

sharding-core/src/main/antlr4/imports/PostgreSQLDALStatement.g4

@@ -3,10 +3,26 @@ grammar PostgreSQLDALStatement;
 import PostgreSQLKeyword, Keyword, BaseRule, DataType, Symbol;
 
 show
-    : SHOW showParam
+    : SHOW (ALL | ID)
+    ;
+
+setParam
+    : SET scope? setClause
+    ;
+
+scope
+    : SESSION | LOCAL
     ;
 
-showParam
-    : ALL
-    | ID
+setClause
+    : TIME ZONE timeZoneType
+    | ID (TO | EQ_) (STRING | DEFAULT)
     ;
+
+timeZoneType
+    : NUMBER | LOCAL | DEFAULT
+    ;
+
+resetParam
+    : RESET (ALL | ID)
+    ;

sharding-core/src/main/antlr4/io/shardingsphere/core/parsing/antlr/autogen/PostgreSQLStatement.g4

@@ -35,4 +35,6 @@ execute
     | alterRoleResetConfig
     | dropRole
     | show
+    | setParam
+    | resetParam
     ;

sharding-core/src/main/java/io/shardingsphere/core/parsing/SQLParsingEngine.java

@@ -62,28 +62,7 @@ public SQLStatement parse(final boolean useCache) {
             return cachedSQLStatement.get();
         }
         LexerEngine lexerEngine = LexerEngineFactory.newInstance(dbType, sql);
-        lexerEngine.nextToken();
-        Token firstToken = lexerEngine.getCurrentToken();
-        SQLStatement result;
-
-        if (PostgreSQLKeyword.SHOW == lexerEngine.getCurrentToken().getType()) {
-            result = AntlrParsingEngine.parse(dbType, sql, shardingRule, shardingTableMetaData);
-            return result;
-        }
-
-        SQLParser sqlParser = SQLParserFactory.newInstance(dbType, lexerEngine.getCurrentToken().getType(), shardingRule, lexerEngine, shardingTableMetaData);
-        Token currentToken = lexerEngine.getCurrentToken();
-        if (firstToken != currentToken) {
-            if (DDLStatement.isDDL(firstToken.getType(), currentToken.getType())) {
-                result = AntlrParsingEngine.parse(dbType, sql, shardingRule, shardingTableMetaData);
-            } else {
-                result = sqlParser.parse();
-            }
-        } else if (TCLStatement.isTCL(firstToken.getType())) {
-            result = AntlrParsingEngine.parse(dbType, sql, shardingRule, shardingTableMetaData);
-        } else {
-            result = sqlParser.parse();
-        }
+        SQLStatement result = SQLParserFactory.newInstance(dbType, shardingRule, lexerEngine, shardingTableMetaData, sql).parse();
         if (useCache) {
             ParsingResultCache.getInstance().put(sql, result);
         }

sharding-core/src/main/java/io/shardingsphere/core/parsing/antlr/AntlrParsingEngine.java

@@ -24,30 +24,30 @@
 import io.shardingsphere.core.parsing.antlr.extractor.statement.SQLStatementExtractorFactory;
 import io.shardingsphere.core.parsing.antlr.extractor.statement.SQLStatementType;
 import io.shardingsphere.core.parsing.parser.exception.SQLParsingUnsupportedException;
+import io.shardingsphere.core.parsing.parser.sql.SQLParser;
 import io.shardingsphere.core.parsing.parser.sql.SQLStatement;
 import io.shardingsphere.core.rule.ShardingRule;
-import lombok.AccessLevel;
-import lombok.NoArgsConstructor;
+import lombok.AllArgsConstructor;
 import org.antlr.v4.runtime.ParserRuleContext;
 
 /**
  * Parsing engine for Antlr.
  *
  * @author duhongjun
  */
-@NoArgsConstructor(access = AccessLevel.PRIVATE)
-public final class AntlrParsingEngine {
+@AllArgsConstructor
+public final class AntlrParsingEngine implements SQLParser {
 
-    /**
-     * Parse SQL.
-     *
-     * @param dbType database type
-     * @param sql SQL
-     * @param shardingRule sharding rule
-     * @param shardingTableMetaData sharding table meta data
-     * @return SQL statement
-     */
-    public static SQLStatement parse(final DatabaseType dbType, final String sql, final ShardingRule shardingRule, final ShardingTableMetaData shardingTableMetaData) {
+    private DatabaseType dbType;
+
+    private String sql;
+
+    private ShardingRule shardingRule;
+
+    private ShardingTableMetaData shardingTableMetaData;
+
+    @Override
+    public SQLStatement parse() {
         ParserRuleContext rootContext = SQLASTParserFactory.newInstance(dbType, sql).execute();
         if (null == rootContext) {
             throw new SQLParsingUnsupportedException(String.format("Unsupported SQL of `%s`", sql));

sharding-core/src/main/java/io/shardingsphere/core/parsing/antlr/extractor/segment/engine/dialect/postgresql/ShowParamExtractor.java

@@ -1,3 +1,20 @@
+/*
+ * Copyright 2016-2018 shardingsphere.io.
+ * <p>
+ * Licensed 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.
+ * </p>
+ */
+
 package io.shardingsphere.core.parsing.antlr.extractor.segment.engine.dialect.postgresql;
 
 import com.google.common.base.Optional;
@@ -8,6 +25,11 @@
 import io.shardingsphere.core.parsing.antlr.sql.segment.ShowParamSegment;
 import org.antlr.v4.runtime.ParserRuleContext;
 
+/**
+ * PostgreSQL show param extractor.
+ *
+ * @author loxp
+ */
 public class ShowParamExtractor implements OptionalSQLSegmentExtractor {
 
     @Override

sharding-core/src/main/java/io/shardingsphere/core/parsing/antlr/extractor/statement/SQLStatementType.java

@@ -53,6 +53,10 @@ public enum SQLStatementType {
 
     SET_VARIABLE("SetVariable"),
 
+    SET_PARAM("SetParam"), // PostgreSQL SET statement
+
+    RESET_PARAM("ResetParam"),
+
     SHOW("Show");
 
     private final String name;

sharding-core/src/main/java/io/shardingsphere/core/parsing/antlr/extractor/statement/engine/dal/DALStatementExtractor.java

@@ -1,9 +1,31 @@
+/*
+ * Copyright 2016-2018 shardingsphere.io.
+ * <p>
+ * Licensed 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.
+ * </p>
+ */
+
 package io.shardingsphere.core.parsing.antlr.extractor.statement.engine.dal;
 
 import io.shardingsphere.core.parsing.antlr.extractor.statement.engine.AbstractSQLStatementExtractor;
 import io.shardingsphere.core.parsing.parser.sql.SQLStatement;
 import io.shardingsphere.core.parsing.parser.sql.dal.DALStatement;
 
+/**
+ * DAL statement extractor.
+ *
+ * @author loxp
+ */
 public abstract class DALStatementExtractor extends AbstractSQLStatementExtractor {
 
     @Override

sharding-core/src/main/java/io/shardingsphere/core/parsing/antlr/extractor/statement/engine/dal/dialect/postgresql/PostgreSQLResetParamExtractor.java

@@ -0,0 +1,35 @@
+/*
+ * Copyright 2016-2018 shardingsphere.io.
+ * <p>
+ * Licensed 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.
+ * </p>
+ */
+
+package io.shardingsphere.core.parsing.antlr.extractor.statement.engine.dal.dialect.postgresql;
+
+import io.shardingsphere.core.parsing.antlr.extractor.statement.engine.dal.DALStatementExtractor;
+import io.shardingsphere.core.parsing.parser.dialect.postgresql.statement.ResetParamStatement;
+import io.shardingsphere.core.parsing.parser.sql.SQLStatement;
+
+/**
+ * PostgreSQL reset param statement extractor.
+ *
+ * @author loxp
+ */
+public class PostgreSQLResetParamExtractor extends DALStatementExtractor {
+
+    @Override
+    protected SQLStatement createStatement() {
+        return new ResetParamStatement();
+    }
+}

sharding-core/src/main/java/io/shardingsphere/core/parsing/antlr/extractor/statement/engine/dal/dialect/postgresql/PostgreSQLSetParamExtractor.java

@@ -0,0 +1,37 @@
+/*
+ * Copyright 2016-2018 shardingsphere.io.
+ * <p>
+ * Licensed 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.
+ * </p>
+ */
+
+package io.shardingsphere.core.parsing.antlr.extractor.statement.engine.dal.dialect.postgresql;
+
+import io.shardingsphere.core.parsing.antlr.extractor.statement.engine.dal.DALStatementExtractor;
+import io.shardingsphere.core.parsing.parser.dialect.postgresql.statement.SetParamStatement;
+import io.shardingsphere.core.parsing.parser.sql.SQLStatement;
+import lombok.NoArgsConstructor;
+
+/**
+ * PostgreSQL set param statement extractor.
+ *
+ * @author loxp
+ */
+@NoArgsConstructor
+public class PostgreSQLSetParamExtractor extends DALStatementExtractor {
+
+    @Override
+    protected SQLStatement createStatement() {
+        return new SetParamStatement();
+    }
+}

sharding-core/src/main/java/io/shardingsphere/core/parsing/antlr/extractor/statement/engine/dal/dialect/postgresql/PostgreSQLShowExtractor.java

@@ -1,10 +1,32 @@
+/*
+ * Copyright 2016-2018 shardingsphere.io.
+ * <p>
+ * Licensed 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.
+ * </p>
+ */
+
 package io.shardingsphere.core.parsing.antlr.extractor.statement.engine.dal.dialect.postgresql;
 
 import io.shardingsphere.core.parsing.antlr.extractor.segment.engine.dialect.postgresql.ShowParamExtractor;
 import io.shardingsphere.core.parsing.antlr.extractor.statement.engine.dal.DALStatementExtractor;
 import io.shardingsphere.core.parsing.parser.dialect.postgresql.statement.ShowStatement;
 import io.shardingsphere.core.parsing.parser.sql.SQLStatement;
 
+/**
+ * PostgreSQL show statement extractor.
+ *
+ * @author loxp
+ */
 public final class PostgreSQLShowExtractor extends DALStatementExtractor {
 
     public PostgreSQLShowExtractor() {

sharding-core/src/main/java/io/shardingsphere/core/parsing/antlr/extractor/statement/registry/dialect/PostgreSQLStatementExtractorRegistry.java

@@ -19,6 +19,8 @@
 
 import io.shardingsphere.core.parsing.antlr.extractor.statement.SQLStatementExtractor;
 import io.shardingsphere.core.parsing.antlr.extractor.statement.SQLStatementType;
+import io.shardingsphere.core.parsing.antlr.extractor.statement.engine.dal.dialect.postgresql.PostgreSQLResetParamExtractor;
+import io.shardingsphere.core.parsing.antlr.extractor.statement.engine.dal.dialect.postgresql.PostgreSQLSetParamExtractor;
 import io.shardingsphere.core.parsing.antlr.extractor.statement.engine.dal.dialect.postgresql.PostgreSQLShowExtractor;
 import io.shardingsphere.core.parsing.antlr.extractor.statement.engine.ddl.CreateIndexExtractor;
 import io.shardingsphere.core.parsing.antlr.extractor.statement.engine.ddl.CreateTableExtractor;
@@ -65,6 +67,8 @@ private static void registerTCL() {
 
     private static void registerDAL() {
         EXTRACTORS.put(SQLStatementType.SHOW, new PostgreSQLShowExtractor());
+        EXTRACTORS.put(SQLStatementType.SET_PARAM, new PostgreSQLSetParamExtractor());
+        EXTRACTORS.put(SQLStatementType.RESET_PARAM, new PostgreSQLResetParamExtractor());
     }
 
     @Override

sharding-core/src/main/java/io/shardingsphere/core/parsing/antlr/filler/engnie/ShowParamSegmentFiller.java

@@ -1,3 +1,20 @@
+/*
+ * Copyright 2016-2018 shardingsphere.io.
+ * <p>
+ * Licensed 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.
+ * </p>
+ */
+
 package io.shardingsphere.core.parsing.antlr.filler.engnie;
 
 import io.shardingsphere.core.metadata.table.ShardingTableMetaData;
@@ -7,6 +24,11 @@
 import io.shardingsphere.core.parsing.parser.dialect.postgresql.statement.ShowStatement;
 import io.shardingsphere.core.parsing.parser.sql.SQLStatement;
 
+/**
+ * Show param segment filler.
+ *
+ * @author loxp
+ */
 public class ShowParamSegmentFiller implements SQLSegmentFiller {
     @Override
     public void fill(SQLSegment sqlSegment, SQLStatement sqlStatement, ShardingTableMetaData shardingTableMetaData) {

sharding-core/src/main/java/io/shardingsphere/core/parsing/antlr/sql/segment/ShowParamSegment.java

@@ -1,9 +1,31 @@
+/*
+ * Copyright 2016-2018 shardingsphere.io.
+ * <p>
+ * Licensed 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.
+ * </p>
+ */
+
 package io.shardingsphere.core.parsing.antlr.sql.segment;
 
 import lombok.Getter;
 import lombok.RequiredArgsConstructor;
 import lombok.Setter;
 
+/**
+ * Show param segment.
+ *
+ * @author loxp
+ */
 @RequiredArgsConstructor
 @Getter
 @Setter

sharding-core/src/main/java/io/shardingsphere/core/parsing/lexer/dialect/postgresql/PostgreSQLKeyword.java

@@ -65,5 +65,6 @@ public enum PostgreSQLKeyword implements Keyword {
     INITIALLY,
     DEFERRED,
     IMMEDIATE,
-    EXTRACT
+    EXTRACT,
+    CONSTRAINTS
 }

sharding-core/src/main/java/io/shardingsphere/core/parsing/lexer/token/DefaultKeyword.java

@@ -156,7 +156,8 @@ public enum DefaultKeyword implements Keyword {
     COMMIT,
     ROLLBACK,
     SAVEPOINT,
-    BEGIN, 
+    BEGIN,
+    TRANSACTION,
 
     /*
     Other Command