Can Togglz more than one activation strategy be associated with a feature?

[Chris]

Here is an example scenario that would be common for our product:
- To allow for beta testing turn on a specific feature to a select set of tenants
- If beta testing goes well continue to allow the beta tenants to have access and progressively roll out on a percentage basis to everyone else

First use a custom strategy that allows for the selection of tenants would need to be associated.  Then later add a second custom strategy would need to be added which would allow for a percentage based roll out.

[Steele, Richard]

I agree this would be great to have.  In fact, I implemented a composite activation strategy as a custom class.  It wasn't too hard, but the biggest problem is that the configuration (using properties files) is....messy.

[Christian Kaltepoth]

Sorry for the delayed response.

It's correct that Togglz currently only supports one activation strategy for each feature. To be honest I'm not convinced yet that adding support for multiple strategies is a good idea. It would be a major API break I guess.

My recommendation is to follow Richard's idea and implement a composite strategy for that. That should really be very easy. I think we could perhaps provide some base class that simplifies creating it even further.

Christian

--

Christian Kaltepoth

Blog: http://blog.kaltepoth.de/

Twitter: http://twitter.com/chkal

GitHub: https://github.com/chkal

[Charith De Silva]

Hi Chris 

I'm in the similar need of having overloaded strategies for a given feature. Can you please elaborate how I can implement this with minimum effort and having console to reflect the selected strategies too. 

cheers

Charith 

[Christian Kaltepoth]

Hey,

Basically you just have to create a custom strategy like described in the documentation:

http://www.togglz.org/documentation/activation-strategies.html#custom

And the implementation should basically combine two "child" strategies like this:

• isActive(): Call isActive() on both "child" strategies. Return true if both return true.
• getParameters(): Call isParameters() on both child strategies and return a list containing all parameters.

That's all. ;-)

Christian

[Charith De Silva]

Hi Christian 

Thanks for your reply. Heading into my next issue. I have EAR packaging. I've Togglz working perfectly for web context(WAR). Now I need to make this available for application context too. Application is written is wired through spring. No EJBs though. Can you please let me know the best approach to use togglz in such structure? 

Thanks 
Charith 

[Christian Kaltepoth]

I'm not very familiar with Spring to be honest. The question is if you can define a Spring managed bean in some global context for the EAR. Is there a global application context in your setup?

[Charith De Silva]

Thanks Christian. I've got it working in EAR. Basically I've followed the standalone way to trigger this on the application context. You need to make sure to exclude the servlet, core from the web context ( i.e. through web pom file). Using spi i've loaded my spring togglzConfiguration through feature manager builder and I'm back online again for the entire application ;) 

Thanks again for help. 

public class SingletonFeatureManagerProvider implements FeatureManagerProvider {

    private static FeatureManager featureManager;

    @Override

    public int priority() {

        return 30;

    }

    @Override

    public synchronized FeatureManager getFeatureManager() {

   

        TogglzConfig togglzConfig = ContextAware.getBean(TogglzConfiguration.class); // initialize spring bean 

        

        if (featureManager == null) {

            featureManager = new FeatureManagerBuilder().togglzConfig(togglzConfig).build();

        }

        return featureManager;

    }

}

[Charith De Silva]

Hi Christian 

Thanks for the post. I've done a base strategy class that can mix and match strategies through spring config. So if you are on spring, you can create many composite strategies as possible without touching java code. Sharing configuration for future users. cheers!

  <!-- Togglz composite strategies -->

<bean id="demoCuzStrategy1" class="myservice.togglz.ActivationStrategyBase">

<property name="name" value="Demo Strategy 1" />

<property name="id" value="demo1" />

   <property name="activationStrategies">

       <list value-type="org.togglz.core.spi.ActivationStrategy">

           <ref bean="myTestActivationStrategy"/>

           <ref bean="usernameActivationStrategy"/>

       </list>

    </property>

</bean>

 

import java.util.ArrayList;

import java.util.Arrays;

import java.util.List;

import org.togglz.core.activation.Parameter;

import org.togglz.core.repository.FeatureState;

import org.togglz.core.spi.ActivationStrategy;

import org.togglz.core.user.FeatureUser;

/**

 * <p>

 * This Base activation strategy implementation can be used to composite custom strategies through spring application context.

 * You can mix-match both custom strategies and togglz built-in strategies to build up custom strategies without touching java code.  

 * </p>

 * 

 * @author cdesilva

 */

public class ActivationStrategyBase implements ActivationStrategy{

    public String id;

    public String name;

    

private List<ActivationStrategy> activationStrategies;

    

    @Override

    public String getId() {

        return id;

    }

    @Override

    public String getName() {

        return name;

    }

    @Override

    public boolean isActive(FeatureState featureState, FeatureUser user) {

   

    boolean isActive = true; 

    // Validate all composite strategies. 

    for (ActivationStrategy strategy : activationStrategies) {

    if (!strategy.isActive(featureState, user)) {

    isActive = false;

    break; 

    }

    }

        return isActive;

    }

    @Override

    public Parameter[] getParameters() {

    List<Parameter> parametersList = new ArrayList<>();

   

    // Collect parameters from composite strategies.

    for (ActivationStrategy strategy : activationStrategies) {

    parametersList.addAll(new ArrayList<Parameter>(

    Arrays.asList(strategy.getParameters())));

    }

   

    return parametersList.toArray(new Parameter[parametersList.size()]);

    }

public List<ActivationStrategy> getActivationStrategies() {

return activationStrategies;

}

public void setActivationStrategies(

List<ActivationStrategy> activationStrategies) {

this.activationStrategies = activationStrategies;

}

public void setId(String id) {

this.id = id;

}

public void setName(String name) {

this.name = name;

}

}

[Christian Kaltepoth]

Great, thanks for sharing! :-)