Contributing to JMeter

As part of my using JMeter for the purpose of testing a new Transactional storage engine PBXT for MySQL, I’ve been investigating the best approach for handling transactions. Read more about earlier decisions at my earlier post Testing a new MySQL Transactional Storage Engine .

I found that the JMeter JDBC Sampler only supports SELECT and UPDATE Statements, and not calls to stored procedures. This is just one approach I’m considering taking.

Well, I guess it’s time to contribute code to an Apache Project. I’ve modified code and logged bugs before for Tomcat, but this will be my first attempt of modify code and submit.

A summary of what I did (really for my own short term memory):

Now I just have to wait to see if it’s accepted. Regardless, it works for me. And that’s Open Source. FREEDOM
<br /> svn checkout http://svn.apache.org/repos/asf/jakarta/jmeter/trunk/ jmeter<br />

$ svn diff JDBCSampler.java > JDBCSampler.java.patch
$ cat  JDBCSampler.java.patch
Index: JDBCSampler.java
===================================================================
--- JDBCSampler.java    (revision 388876)
+++ JDBCSampler.java    (working copy)
@@ -23,6 +23,7 @@
 import java.sql.ResultSetMetaData;
 import java.sql.SQLException;
 import java.sql.Statement;
+import java.sql.CallableStatement;

 import org.apache.avalon.excalibur.datasource.DataSourceComponent;
 import org.apache.jmeter.samplers.Entry;
@@ -45,6 +46,8 @@

        public static final String QUERY = "query";
        public static final String SELECT = "Select Statement";
+       public static final String UPDATE = "Update Statement";
+       public static final String STATEMENT = "Call Statement";

        public String query = "";

@@ -69,6 +72,7 @@
                log.debug("DataSourceComponent: " + pool);
                Connection conn = null;
                Statement stmt = null;
+               CallableStatement cs = null;

                try {

@@ -88,14 +92,19 @@
                                        Data data = getDataFromResultSet(rs);
                                        res.setResponseData(data.toString().getBytes());
                                } finally {
-                                       if (rs != null) {
-                                               try {
-                                                       rs.close();
-                                               } catch (SQLException exc) {
-                                                       log.warn("Error closing ResultSet", exc);
-                                               }
-                                       }
+                                       close(rs);
                                }
+                       // execute stored procedure
+                       } else if (STATEMENT.equals(getQueryType())) {
+                               try {
+                                       cs = conn.prepareCall(getQuery());
+                                       cs.execute();
+                                       String results = "Executed";
+                                       res.setResponseData(results.getBytes());
+                               } finally {
+                                       close(cs);
+                               }
+                       // Insert/Update/Delete statement
                        } else {
                                stmt.execute(getQuery());
                                int updateCount = stmt.getUpdateCount();
@@ -112,20 +121,8 @@
                        res.setResponseMessage(ex.toString());
                        res.setSuccessful(false);
                } finally {
-                       if (stmt != null) {
-                               try {
-                                       stmt.close();
-                               } catch (SQLException ex) {
-                                       log.warn("Error closing statement", ex);
-                               }
-                       }
-                       if (conn != null) {
-                               try {
-                                       conn.close();
-                               } catch (SQLException ex) {
-                                       log.warn("Error closing connection", ex);
-                               }
-                       }
+                       close(stmt);
+                       close(conn);
                }

                res.sampleEnd();
@@ -164,6 +161,38 @@
                return data;
        }

+       public static void close(Connection c) {
+               try {
+                       if (c != null) c.close();
+               } catch (SQLException e) {
+                       log.warn("Error closing Connection", e);
+               }
+       }
+
+       public static void close(Statement s) {
+               try {
+                       if (s != null) s.close();
+               } catch (SQLException e) {
+                       log.warn("Error closing Statement", e);
+               }
+       }
+
+       public static void close(CallableStatement cs) {
+               try {
+                       if (cs != null) cs.close();
+               } catch (SQLException e) {
+                       log.warn("Error closing CallableStatement", e);
+               }
+       }
+
+       public static void close(ResultSet rs) {
+               try {
+                       if (rs != null) rs.close();
+               } catch (SQLException e) {
+                       log.warn("Error closing ResultSet", e);
+               }
+       }
+
        public String getQuery() {
                return query;
        }

$ svn diff JDBCSamplerBeanInfo.java > JDBCSamplerBeanInfo.java.patch
$ cat JDBCSamplerBeanInfo.java.patch
Index: JDBCSamplerBeanInfo.java
===================================================================
--- JDBCSamplerBeanInfo.java    (revision 388876)
+++ JDBCSamplerBeanInfo.java    (working copy)
@@ -50,7 +50,7 @@
                p.setValue(NOT_UNDEFINED, Boolean.TRUE);
                p.setValue(DEFAULT, JDBCSampler.SELECT);
                p.setValue(NOT_OTHER,Boolean.TRUE);
-               p.setValue(TAGS,new String[]{JDBCSampler.SELECT,"Update Statement"});
+               p.setValue(TAGS,new String[]{JDBCSampler.SELECT,JDBCSampler.UPDATE,JDBCSampler.STATEMENT});

                p = property("query");
                p.setValue(NOT_UNDEFINED, Boolean.TRUE);

Update

Good to know somebody read my post, and responded positively. The quickest way for patches is to log a Bugzilla request. Seemed somebody already had, so it was easy for me to just to contribute to Bug #38682

Tagged with: Databases General Java MySQL Open Source PBXT

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