Using Spring Security with CXF in Grails

CXF plugin is super easy way to add SOAP web service to Grails application. It creates regular service class, with few specific parameters and voila - you have SOAP. But what if you want security?
REST web services are native citizens in Grails - they are just actions in controllers, so you can use Spring Security annotations to check permissions. But there is no annotations for services. There are two easy options.
First, you can restrict actions by defining static rules. This is very simple, but not very flexible as it does not allow to configure permissions on method level, you will have to create different services for different permissions. Also, old clients may not work if WSDL requires authentication.
Second method, is to check permissions manually. In practice this is similar to annotations, and can be converted to annotations easily. There is example:

  Secret secret(int id) {
    checkRights("VIEW_SECRET")
    return Secret.get(id)
  }

  void checkRights(String rights) {
    if (!SpringSecurityUtils.ifAllGranted(rights)) {
      throw new IllegalAccessException("You don't have permission")
    }
  }

Finding similar strings in Java

Finding equal strings in Java is very easy, as well as finding substrings. But what if you have strings that are almost similar (at least from human point of view). For example: "John Doe" and "Doo Jonh".
Recently, I had to do data migration for table with very poor data quality. There is a lot of theory and books on finding duplicates, but surprisingly, there is very little actual Java implementations that could help with such things. Fortunately, there is at least one good - Simmetrics, there is even example how to use it, but it is as simple as one can imagine:

import uk.ac.shef.wit.simmetrics.similaritymetrics.*;

AbstractStringMetric metric = new MongeElkan()
println ( ['John John', 'Doo Jonh', 'ddddddd', '7777777777'].max { metric.getSimilarity('John Doe', it) })

Doo Jonh

There is a bunch of different algorithms one can use, but I found MongeElkan to be best for my case.

Javamelody SQL monitoring with Grails plugin

Javamelody is amazing tool for live monitoring. It has great Grails plugin which makes it very easy to use. Only issue I had with it is SQL monitoring configuration.
According to documentation there are several ways to configure data sources:

1. magic - you don't have to do anything, it just works
2. javamelody.datasources property in GrailsMelodyConfig.groovy - you just specify datasources
3. replacing JDBC driver with Javamelody proxy
4. specifying java option - javamelody.datasources

Unfortunately, all internal configuration options (1, 2, 3) didn't worked. As I investigated (quickly) it looks like there is no dataSource bean available for BeanPostProcessor and it tries to proxy after all connections were already picked by application.
So only specifying java command line option worked for me. Otherwise - great tool. It is also possible to specify multiple data sources with command line like:

-Djavamelody.datasources=java:comp/env/ds1,java:comp/env/ds2

Getting object from calling method in Java

This is hardly production scenario, but at some point I wanted to find value of a variable from a caller class. Looks like this is not trivial task and is much more complicated than it should be (for some reason), however still possible.
Finding method and class name is easy via Thread class, but accessing real objects seems to be only possible with Java Debug Interface. For this purpose, application must be executed in debug mode (for grails it is with grails-debug command). There is no need for any additional library as everything is included into JDK and probably is used by JDK debugger.
General scenario is as folows:

• connect with debugger provided with JDI via socket (there are other options, but sockets seems default for most tools)
• spawn new thread where you will wait to do whatever you want to do with data on stack trace
• suspend application at point where you want to do it
• at the end of your work - continue application

There is example:

def att = com.sun.jdi.Bootstrap.virtualMachineManager().attachingConnectors().find{it instanceof com.sun.tools.jdi.SocketAttachingConnector}
Map arguments = att.defaultArguments()
com.sun.jdi.connect.Connector.Argument hostArg = arguments.get("hostname").setValue("localhost")
com.sun.jdi.connect.Connector.Argument portArg = arguments.get("port").setValue("5005")
com.sun.jdi.VirtualMachine vm = att.attach(arguments);
def thread = vm.allThreads().find {it.name()=='main'}
def runnable = new Runnable() {
  void run() {
 while (!thread.isSuspended() ) {
   Thread.sleep(100)
 }
 def frames = thread.frames().findAll {it.location().toString() =~ /grails.plugin.spock.test.listener.PerSpecRunListener:.*/}
 frames.each {frame->
   def res = frame.thisObject()
   def field = res.type().fieldByName("failureCount")
   if (field) {
       def countref = res.getValue(field).toString()
        ...
      }
   }
     thread.resume()
  }
}
new Thread(runnable).start()
thread.suspend() 

IntelliJ IDEA Select In view with specific view

Intellij IDEA has a lot of great shortcuts, but for some reason there is no special shortcut when you need to find file in specific view, for example Grails view. Normal way to do it, is to press shortcut for "Select In..." (Alt+F1) and select your view (or press number with this view). This is basically 2 shortcuts and not too convenient.
Fortunately it is possible to make it easier by recording a Macro, and assigning it new shortcut. Just go to Edit > Macros > Start Macro recording, press "Select In..." shortcut and select your view.

Downloading URL with login and password

In javadoc there is no clear way on how to download page that requires Basic Authentication, for example like:

  def result = new URL("http://www.requireslogin.com/").getText()

Fortunately, this is still very possible and not too complicated, just add this somewhere before calling URL:

  java.net.Authenticator.setDefault(new java.net.Authenticator() {
    protected java.net.PasswordAuthentication getPasswordAuthentication() {
      return new java.net.PasswordAuthentication("user", "password".toCharArray());
    }
  });

Possibly it would be better to have login and password as parameters, but this still works.

Adding Ant optional task to Grails

Since version 2 Grails does not include Sshexec with built-in Gant libs, so it broke some of my deployment scripts. Fortunately it is easy to fix with nothing more than few Grapes annotations added to your Gant script:

...

@Grapes([
  @Grab(group ="org.apache.ant", module = "ant-jsch", version ="1.8.1"),
  @Grab(group ="com.jcraft", module = "jsch", version ="0.1.48"),
  @GrabConfig(systemClassLoader = true)
])

...

Possibly, there are other options like adding libs to some magic folders, but I found this one best as it avoids additional configuration, is self explanatory and hard to skip or forget as it is in script itself.