[ZEPPELIN-3377] Passing Z variables to JDBC interpreter

docs/interpreter/jdbc.md

@@ -192,6 +192,10 @@ There are more JDBC interpreter properties you can specify like below.
     <td>default.jceks.credentialKey</td>
     <td>jceks credential key</td>
   </tr>
+  <tr>
+    <td>zeppelin.jdbc.interpolation</td>
+    <td>Enables ZeppelinContext variable interpolation into paragraph text. Default value is false.</td>
+  </tr>
 </table>
 
 You can also add more properties by using this [method](http://docs.oracle.com/javase/7/docs/api/java/sql/DriverManager.html#getConnection%28java.lang.String,%20java.util.Properties%29).
@@ -240,7 +244,7 @@ You can leverage [Zeppelin Dynamic Form](../usage/dynamic_form/intro.html) insid
 %jdbc_interpreter_name
 SELECT name, country, performer
 FROM demo.performers
-WHERE name='{{"{{performer=Sheryl Crow|Doof|Fanfarlo|Los Paranoia"}}}}'
+WHERE name='${performer=Sheryl Crow|Doof|Fanfarlo|Los Paranoia}'
 ```
 ### Usage *precode*
 You can set *precode* for each data source. Code runs once while opening the connection.
@@ -724,5 +728,27 @@ Before Adding one of the below dependencies, check the Phoenix version first.
 
 [Maven Repository: org.apache.tajo:tajo-jdbc](https://mvnrepository.com/artifact/org.apache.tajo/tajo-jdbc)
 
+## Object Interpolation
+The JDBC interpreter also supports interpolation of `ZeppelinContext` objects into the paragraph text.
+The following example shows one use of this facility:
+
+####In Scala cell:
+```
+z.put("country_code", "KR")
+    // ...
+```
+
+####In later JDBC cell:
+```sql
+%jdbc_interpreter_name
+    select * from patents_list where 
+    priority_country = '{country_code}' and filing_date like '2015-%'
+```
+
+Object interpolation is disabled by default, and can be enabled for all instances of the JDBC interpreter by 
+setting the value of the property `zeppelin.jdbc.interpolation` to `true` (see _More Properties_ above). 
+More details of this feature can be found in the Spark interpreter documentation under 
+[Object Interpolation](spark.html#object-interpolation)
+
 ## Bug reporting
 If you find a bug using JDBC interpreter, please create a [JIRA](https://issues.apache.org/jira/browse/ZEPPELIN) ticket.

jdbc/src/main/java/org/apache/zeppelin/jdbc/JDBCInterpreter.java

@@ -782,7 +782,9 @@ private String replaceReservedChars(String str) {
   }
 
   @Override
-  public InterpreterResult interpret(String cmd, InterpreterContext contextInterpreter) {
+  public InterpreterResult interpret(String originalCmd, InterpreterContext contextInterpreter) {
+    String cmd = Boolean.parseBoolean(getProperty("zeppelin.jdbc.interpolation")) ?
+            interpolate(originalCmd, contextInterpreter.getResourcePool()) : originalCmd;
     logger.debug("Run SQL command '{}'", cmd);
     String propertyKey = getPropertyKey(cmd);
 

jdbc/src/main/resources/interpreter-setting.json

@@ -101,6 +101,13 @@
         "defaultValue": "",
         "description": "Kerberos principal",
         "type": "string"
+      },
+      "zeppelin.jdbc.interpolation": {
+        "envName": null,
+        "propertyName": "zeppelin.jdbc.interpolation",
+        "defaultValue": false,
+        "description": "Enable ZeppelinContext variable interpolation into paragraph text",
+        "type": "checkbox"
       }
     },
     "editor": {

jdbc/src/test/java/org/apache/zeppelin/jdbc/JDBCInterpreterInterpolationTest.java

@@ -0,0 +1,181 @@
+/**
+ * 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.zeppelin.jdbc;
+
+import com.mockrunner.jdbc.BasicJDBCTestCaseAdapter;
+import org.apache.zeppelin.interpreter.InterpreterContext;
+import org.apache.zeppelin.interpreter.InterpreterResult;
+import org.apache.zeppelin.resource.LocalResourcePool;
+import org.apache.zeppelin.resource.ResourcePool;
+import org.apache.zeppelin.user.AuthenticationInfo;
+import org.junit.Before;
+import org.junit.Test;
+
+import java.io.IOException;
+import java.nio.file.Files;
+import java.nio.file.Path;
+import java.sql.Connection;
+import java.sql.DriverManager;
+import java.sql.Statement;
+import java.util.Properties;
+
+import static java.lang.String.format;
+import static org.junit.Assert.assertEquals;
+
+/**
+ * JDBC interpreter Z-variable interpolation unit tests.
+ */
+public class JDBCInterpreterInterpolationTest extends BasicJDBCTestCaseAdapter {
+
+  private static String jdbcConnection;
+  private InterpreterContext interpreterContext;
+  private ResourcePool resourcePool;
+
+  private String getJdbcConnection() throws IOException {
+    if (null == jdbcConnection) {
+      Path tmpDir = Files.createTempDirectory("h2-test-");
+      tmpDir.toFile().deleteOnExit();
+      jdbcConnection = format("jdbc:h2:%s", tmpDir);
+    }
+    return jdbcConnection;
+  }
+
+  @Before
+  public void setUp() throws Exception {
+    Class.forName("org.h2.Driver");
+    Connection connection = DriverManager.getConnection(getJdbcConnection());
+    Statement statement = connection.createStatement();
+    statement.execute(
+          "DROP TABLE IF EXISTS test_table; " +
+          "CREATE TABLE test_table(id varchar(255), name varchar(255));");
+
+    Statement insertStatement = connection.createStatement();
+    insertStatement.execute("insert into test_table(id, name) values " +
+                "('pro', 'processor')," +
+                "('mem', 'memory')," +
+                "('key', 'keyboard')," +
+                "('mou', 'mouse');");
+    resourcePool = new LocalResourcePool("JdbcInterpolationTest");
+
+    interpreterContext = new InterpreterContext("", "1", null, "", "",
+            new AuthenticationInfo("testUser"), null, null, null, null, resourcePool, null, null);
+  }
+
+  @Test
+  public void testEnableDisableProperty() throws IOException {
+    Properties properties = new Properties();
+    properties.setProperty("common.max_count", "1000");
+    properties.setProperty("common.max_retry", "3");
+    properties.setProperty("default.driver", "org.h2.Driver");
+    properties.setProperty("default.url", getJdbcConnection());
+    properties.setProperty("default.user", "");
+    properties.setProperty("default.password", "");
+
+    resourcePool.put("zid", "mem");
+    String sqlQuery = "select * from test_table where id = '{zid}'";
+
+    //
+    // Empty result expected because "zeppelin.jdbc.interpolation" is false by default ...
+    //
+    JDBCInterpreter t = new JDBCInterpreter(properties);
+    t.open();
+    InterpreterResult interpreterResult = t.interpret(sqlQuery, interpreterContext);
+    assertEquals(InterpreterResult.Code.SUCCESS, interpreterResult.code());
+    assertEquals(InterpreterResult.Type.TABLE, interpreterResult.message().get(0).getType());
+    assertEquals(1, interpreterResult.message().size());
+    assertEquals("ID\tNAME\n", interpreterResult.message().get(0).getData());
+
+    //
+    // 1 result expected because "zeppelin.jdbc.interpolation" set to "true" ...
+    //
+    properties.setProperty("zeppelin.jdbc.interpolation", "true");
+    t = new JDBCInterpreter(properties);
+    t.open();
+    interpreterResult = t.interpret(sqlQuery, interpreterContext);
+    assertEquals(InterpreterResult.Code.SUCCESS, interpreterResult.code());
+    assertEquals(InterpreterResult.Type.TABLE, interpreterResult.message().get(0).getType());
+    assertEquals(1, interpreterResult.message().size());
+    assertEquals("ID\tNAME\nmem\tmemory\n",
+            interpreterResult.message().get(0).getData());
+  }
+
+  @Test
+  public void testNormalQueryInterpolation() throws IOException {
+    Properties properties = new Properties();
+    properties.setProperty("common.max_count", "1000");
+    properties.setProperty("common.max_retry", "3");
+    properties.setProperty("default.driver", "org.h2.Driver");
+    properties.setProperty("default.url", getJdbcConnection());
+    properties.setProperty("default.user", "");
+    properties.setProperty("default.password", "");
+
+    properties.setProperty("zeppelin.jdbc.interpolation", "true");
+
+    JDBCInterpreter t = new JDBCInterpreter(properties);
+    t.open();
+
+    //
+    // Empty result expected because "kbd" is not defined ...
+    //
+    String sqlQuery = "select * from test_table where id = '{kbd}'";
+    InterpreterResult interpreterResult = t.interpret(sqlQuery, interpreterContext);
+    assertEquals(InterpreterResult.Code.SUCCESS, interpreterResult.code());
+    assertEquals(InterpreterResult.Type.TABLE, interpreterResult.message().get(0).getType());
+    assertEquals(1, interpreterResult.message().size());
+    assertEquals("ID\tNAME\n", interpreterResult.message().get(0).getData());
+
+    resourcePool.put("itemId", "key");
+
+    //
+    // 1 result expected because z-variable 'item' is 'key' ...
+    //
+    sqlQuery = "select * from test_table where id = '{itemId}'";
+    interpreterResult = t.interpret(sqlQuery, interpreterContext);
+    assertEquals(InterpreterResult.Code.SUCCESS, interpreterResult.code());
+    assertEquals(InterpreterResult.Type.TABLE, interpreterResult.message().get(0).getType());
+    assertEquals(1, interpreterResult.message().size());
+    assertEquals("ID\tNAME\nkey\tkeyboard\n",
+            interpreterResult.message().get(0).getData());
+  }
+
+  @Test
+  public void testEscapedInterpolationPattern() throws IOException {
+    Properties properties = new Properties();
+    properties.setProperty("common.max_count", "1000");
+    properties.setProperty("common.max_retry", "3");
+    properties.setProperty("default.driver", "org.h2.Driver");
+    properties.setProperty("default.url", getJdbcConnection());
+    properties.setProperty("default.user", "");
+    properties.setProperty("default.password", "");
+
+    properties.setProperty("zeppelin.jdbc.interpolation", "true");
+
+    JDBCInterpreter t = new JDBCInterpreter(properties);
+    t.open();
+
+    //
+    // 2 rows (keyboard and mouse) expected when searching names with 2 consecutive vowels ...
+    // The 'regexp' keyword is specific to H2 database
+    //
+    String sqlQuery = "select * from test_table where name regexp '[aeiou]{{2}}'";
+    InterpreterResult interpreterResult = t.interpret(sqlQuery, interpreterContext);
+    assertEquals(InterpreterResult.Code.SUCCESS, interpreterResult.code());
+    assertEquals(InterpreterResult.Type.TABLE, interpreterResult.message().get(0).getType());
+    assertEquals(1, interpreterResult.message().size());
+    assertEquals("ID\tNAME\nkey\tkeyboard\nmou\tmouse\n", 
+                 interpreterResult.message().get(0).getData());
+  }
+
+}