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At WSO2, we provide middleware solutions for Integration, API Management, Identity Management, IoT and Analytics. Running our products on a local machine is quite straightforward: one just needs to install Java, download the required WSO2 distribution, extract the zip file and run the executable.
This provides a middleware testbed for the user in no time. If the solution needs multiple WSO2 products, those can be run on the same machine by changing the port-offsets and configuring the integrations accordingly.
This works very well for trying out product features and implementing quick PoCs. However, once the preliminary implementation of the project is done, a proper deployment process is needed for moving the system to production.
Any software project needs at least three environments for managing development, testing, and the live deployments. More importantly, a software governance model would be needed for delivering new features, improvement, bug fixes and managing the overall development process.
This becomes crucial when the project implements the system on top of a middleware solution. Both middleware and application changes will need to be delivered. There might be considerable amounts of prerequisites, artifacts and configurations. Without having a well-defined process, it would be difficult to manage such projects efficiently.
A High-Level Examination
One would have to consider the following points would need to be considered when implementing an effective deployment process:
WSO2 middleware can be deployed on physical machines, virtual machines and on containers. Up to now most deployments have been done on virtual machines.
Around 2015, WSO2 users started moving towards container-based deployments using Docker, Kubernetes and Mesos DC/OS. As containers do not need a dedicated operating system instance, this cuts down resource requirements for running an application – in contrast to a VM. In addition, the container ecosystem makes the deployment process much easier using lightweight container images and container image registries.
We provide Puppet Modules, Dockerfiles, Docker Compose, Kubernetes and Mesos (DC/OS) artifacts for automating such deployments.
The configuration for any WSO2 product can be found inside the relevant repository/conf folder. This folder contains a collection of configuration files corresponding to the features that the product provides.
The simplest solution is to maintain these files in a version control system (VCS) such as Git. If the deployment has multiple environments and a collection of products, it might be better to consider using a configuration management system such as Ansible, Puppet, Chef or Salt Stack for reducing configuration value duplication.
We ship Puppet modules for all WSO2 products for this purpose.
WSO2 middleware provides extension points in all WSO2 products for plugging in required features.
For example, in WSO2 Identity Server a custom user store manager can be implemented for connecting to external user stores. In the WSO2 Integration products, handlers or class mediators can be implemented for executing custom mediation logic. Almost all of these extensions are written in Java and deployed as JAR files. These files will simply need to be copied to the repository/components/lib folder or the repository/components/dropins folder if they are OSGi compliant.
Deployable Artifact Management
Artifacts that can be deployed in repository/deployment/server folder fall under this category. For, example, in the ESB, proxy services, REST APIs, inbound endpoints, sequences, security policies can be deployed in runtime via the above folder.
We recommend that you create these artifacts in WSO2 Developer Studio (DevStudio) and package them into Carbon Archive (CAR) files for deploying them as collections. WSO2 DevStudio provides a collection of project templates for managing deployable files of all WSO2 products. These files can be effectively maintained using a VCS.
These files can be effectively maintained using a Version Control System.
Patches were applied to a WSO2 product by copying the patch<number> folder which is found inside the patch zip file to the repository/deployment/patches/ folder.
We recently introduced a new way of applying patches for WSO2 products with WSO2 Update Manager (WUM). The main difference of updates, in contrast to the previous patch model, is that fixes/improvements cannot be applied selectively; it applies all the fixes issued up to a given point using a CLI. This is the main intention of this approach.
In any software project it is important to have at least three environments – one for managing development, one for testing and one for production deployments. New features, bug fixes or improvements need to be first done in the development environment and then moved to the testing environment for verification. Once the functionality and performance are verified the changes can be applied in production (as explained in the “Rolling Out Changes”) section.
The performance verification step might need to have resources identical to the production environment for executing load tests. This is vital for deployments where performance is critical.
With our products, changes can be moved from one environment to the other as a delivery. Deliveries can be numbered and managed via tags in Git.
The key advantage of using this approach is the ability to track, apply and roll back updates at any given time.
Rolling Out Changes
Changes to the existing solution can be rolled out in two main methods:
1. Incremental Deployment (also known as Canary Release).
The idea of this approach is to incrementally apply changes to the existing solution without having to completely switch the entire deployment to the new solution version. This gives the ability to verify the delivery in the production environment using a small portion of the users before propagating it to everyone.
2. Blue-Green Deployment
In Blue-Green deployment method, the deployment is switched to the newer version of the solution at once. It would need an identical set of resources for running the newer version of the solution in parallel to the existing deployment until the newer version is verified. In case of failure, the system can be switched back to the previous version via the router. Taking such approach might need a far more thorough testing procedure compared to the first approach.
Deployment Process Approach 1
This illustrates the simplest form of executing a WSO2 deployment effectively.
In this model the configuration files, deployable artifacts and extension source code are maintained in a version control system. WSO2 product distributions are maintained separately in a file server. Patches/updates are directly applied to the product distributions and new distributions are created. The separation of distributions and artifacts allows product distributions to be updated without losing any project content.
As shown by the green box in the middle, a deployable product distribution is created, combining the latest product distributions, configuration files, deployable artifacts and extensions. Deployable distributions can be extracted on physical, virtual machines or containers and run. Depending on the selected deployment pattern, multiple deployable distributions will need to be created for a product.
In a containerized deployment, each deployable product distribution will have a container image. Depending on the containerized platform, a set of orchestration and load balancing artifacts might also be used.
Deployment Process Approach 2
In the second approach, a configuration management system has been used for reducing the duplication of the configuration data and automating the installation process.
Similar to the first approach, deployable artifacts, configuration data and extension source code are managed in a version control system. Configuration data needs to be stored in a format that is supported by the configuration management system.
For an example, in a Puppet configuration, data is either stored in manifest files or Hiera YAML files. Deployable WSO2 product distributions are not created. Rather, that process is executed by the configuration management system inside a physical machine, virtual machine or in a container at the container build time.
Any of the deployment approaches we’ve spoken about above can be followed with any infrastructure. If a configuration management system is used, it can be used for installing and configuring the solution on virtual machines and as well as on containers. The main difference with containers is that configuration management agent will only be triggered at the container image build time. It may not be run in the when the container is running.
If a configuration management system is used, it can be used for installing and configuring the solution on virtual machines and as well as on containers. The main difference with containers is that configuration management agent will only be triggered at the container image build time. It may not be run in the when the container is running.
At the end of the day, a proper deployment process is essential. For more information and support, please reach out to us. We’d be happy to help.