Skip to main content

Deployer Extension - Handle Binary Unpublish

In case you have written any SDL Tridion Content Delivery Deployer extensions, you have noticed there is no easy way in intercepting the unpublish/undeploy of a binary. This blog post shows how to intercept such an action and execute your custom code on it.

The reason why it is hard to intercept a binary undeploy is because in fact the binary remove does not happen at Deployer level; rather, it takes place in the storage level. So the extension point to be used in not a Deployer extension, but a storage FileSystem or JPA extension.

File System

The following code implements a storage extension that intercepts the removal of a binary from the File System Content Data Storage (fka the File system broker):

package com.tridion.storage.toolkit;

@Component("FSBinaryDAOExtension")
@Scope("prototype")
public class FSBinaryDAOExtension extends FSBinaryContentDAO implements BinaryContentDAO {

    @Override
    public void remove(int publicationId, int binaryId, String variantId,
            String relativePath) throws StorageException {
        // Your custom code goes here

        super.remove(publicationId, binaryId, variantId, relativePath);

        // or here
    }
}

Notice the package must start with com.tridion.storage. Without it, it will not be found during the storage module initialization.

Depending on the requirement, you can place your custom code before or after the call to super.remove.

Database Storage (JPA)

The code below implements a storage extension that uses the Database storage for Content Delivery:

package com.tridion.storage.toolkit;

@Component("JPABinaryDAOExtension")
@Scope("prototype")
public class JPABinaryDAOExtension extends JPABinaryContentDAO implements BinaryContentDAO {

    @Override
    public void remove(int publicationId, int binaryId, String variantId,
            String relativePath) throws StorageException {
        // your custom code goes here

        super.remove(publicationId, binaryId, variantId, relativePath);

        // or here
    }
}

Also note the package must start with com.tridion.storage.

Bundle XML Descriptor

We must configure the custom classes in a bundle XML descriptor file. Below is such a file, in my case called toolkit_dao_bundle.xml:

<?xml version="1.0" encoding="UTF-8"?>
<StorageDAOBundles>
    <!-- Filesystem mappings -->
    <StorageDAOBundle type="filesystem">
        <StorageDAO typeMapping="Binary" 
                    class="com.tridion.storage.toolkit.FSBinaryDAOExtension"/>
    </StorageDAOBundle>

    <!-- Java Persistence API mappings -->
    <StorageDAOBundle type="persistence">
        <StorageDAO typeMapping="Binary" 
                    class="com.tridion.storage.toolkit.JPABinaryDAOExtension"/>
    </StorageDAOBundle>
</StorageDAOBundles>

Place the bundle configuration XML file either on the class-path of your Deployer, or package it in the root position inside your extension JAR.

Final Configuration

The final configuration must be made in cd_storage_conf.xml of you Deployer. Add the following line inside node Global / Storages / StorageBindings:

<Storages>
    <StorageBindings>
        <Bundle src="toolkit_dao_bundle.xml"/>
    </StorageBindings>
...

Restart the Deployer.

With all these configuration and code in place, your custom binary handling code should be called when a Binary is unpublished/undeployed. Remember that in Tridion binaries are only unpublished when they are not referenced anymore by any published Component.



Comments

Popular posts from this blog

Running sp_updatestats on AWS RDS database

Part of the maintenance tasks that I perform on a MSSQL Content Manager database is to run stored procedure sp_updatestats . exec sp_updatestats However, that is not supported on an AWS RDS instance. The error message below indicates that only the sa  account can perform this: Msg 15247 , Level 16 , State 1 , Procedure sp_updatestats, Line 15 [Batch Start Line 0 ] User does not have permission to perform this action. Instead there are several posts that suggest using UPDATE STATISTICS instead: https://dba.stackexchange.com/questions/145982/sp-updatestats-vs-update-statistics I stumbled upon the following post from 2008 (!!!), https://social.msdn.microsoft.com/Forums/sqlserver/en-US/186e3db0-fe37-4c31-b017-8e7c24d19697/spupdatestats-fails-to-run-with-permission-error-under-dbopriveleged-user , which describes a way to wrap the call to sp_updatestats and execute it under a different user: create procedure dbo.sp_updstats with execute as 'dbo' as

Content Delivery Monitoring in AWS with CloudWatch

This post describes a way of monitoring a Tridion 9 combined Deployer by sending the health checks into a custom metric in CloudWatch in AWS. The same approach can also be used for other Content Delivery services. Once the metric is available in CloudWatch, we can create alarms in case the service errors out or becomes unresponsive. The overall architecture is as follows: Content Delivery service sends heartbeat (or exposes HTTP endpoint) for monitoring Monitoring Agent checks heartbeat (or HTTP health check) regularly and stores health state AWS lambda function: runs regularly reads the health state from Monitoring Agent pushes custom metrics into CloudWatch I am running the Deployer ( installation docs ) and Monitoring Agent ( installation docs ) on a t2.medium EC2 instance running CentOS on which I also installed the Systems Manager Agent (SSM Agent) ( installation docs ). In my case I have a combined Deployer that I want to monitor. This consists of an Endpoint and a

Debugging a Tridion 2011 Event System

OK, so you wrote your Tridion Event System. Now it's time to debug it. I know this is a hypothetical situtation -- your code never needs any kind of debugging ;) but indulge me... Recently, Alvin Reyes ( @nivlong ) blogged about being difficult to know how exactly to debug a Tridion Event System. More exactly, the question was " What process do I attach to for debugging even system code? ". Unfortunately, there is no simple or generic answer for it. Different events are fired by different Tridion CM modules. These modules run as different programs (or services) or run inside other programs (e.g. IIS). This means that you will need to monitor (or debug) different processes, based on which events your code handles. So the usual suspects are: dllhost.exe (or dllhost3g.exe ) - running as the MTSUser is the SDL Tridion Content Manager COM+ application and it fires events on generic TOM objects (e.g. events based on Tridion.ContentManager.Extensibility.Events.CrudEven