There are several Magento 2 plugins and observers available over time. However, many Magento users and developers are unaware of the core differences between both options and which one should be used under which condition. In this article, we will compare Magento 2 plugins vs Observers to see which one suits best for your Magento 2 store.
Over the years, we have optimized numerous third-party extensions and customizations where unseasoned developers implemented poor development techniques rather than researching whether they should go with Magento 2 plugins or observers for what they were looking to build.
Now, let’s look at the differences between Magento 2 plugins vs observers and see how effective these development tools are in real-world cases.
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Magento 2 Plugins vs Observers – Which One to Prefer?
As a leading Magento eCommerce website development company, we are here to help you with top-notch Magento 2 module development services to extend the functionalities of your Magento 2 store.
Some Magento 2 extension developers do not make a great deal out of user preferences. However, the way the Magento platform manages preferences prevents us from using them as a practical solution.
We see that preferences are not reliable enough in Magento. Suppose that preferences are used by two different extensions to set the same value. The platform replaces the value using the preference that was loaded last because of the way Magento loads extensions.
So, if two different extensions make use of the same preference to change anything, the preference that gets loaded last will override everyone else’s modifications. This clash will cause huge bugs in extensions that are loaded first, which is intolerable.
If you’re redefining more often, you need to prepare yourself for extensive compatibility testing the next time you opt for Magento 2 store migration and upgrade. This problem arises because if anything is added to the constructor, the impacted class will compel you to add the same code to your own class.
Besides changing the structure, adding new features to the Magento 2 store is another consideration. It leads to slow performance because when Magento gets new features, you need to port them over to your rewritten code. Moreover, even the slightest alteration in the class you have redefined can make your code fail.
Run the command bin/magento setup:di:compile to scan your code for this issue. Even after this, you will not be free from the task of evaluating the source of this change and making your code compatible with the new modifications in the redefined file.
You could use preferences for your Magento store customization if you’re the only one responsible for customizing the store and you’re certain they won’t conflict with each other. In any other scenarios, we advise not using preferences for customization.
Are Event Observers Relevant Anymore?
After removing preferences from the equation, we are left with observers and plugins. Observers are one of the premier options to make changes to the code logic, however, dependency injections and plugins now handle it. Event observers are outdated elements from the Magento 1 time, and their usage is critically limited.
However, many Magento developers use event observers in Magento 2 module development but are unable to implement them correctly. For example, an event observer can be used as an extension to accelerate Checkout.
A poorly constructed observer can significantly affect the entire store’s performance. If you connect the observer to the model load after the event and create a poorly optimized function there, the Magento store can become extremely slow.
If you’re involved in Magento eCommerce website development, we recommend you to remove unwanted plugins and event observers to optimize Magento 2 speed.
However, event observers are not entirely useless as they still have a good number of uses. One good example of its uses is the creation of extension points within private or protected Magento methods.
You can also use observers if you need to log something specific, clean the cache, or transfer data to another system. They are ideal for tracking changes/creation/removal/initialization of specific models inherited from \Magento\Framework\Model\AbstractModel.
However, there is one critical factor to consider. For example, we need to track every new model ID in a log file. You need to write a plugin for each model in the system that supports AbstractModel inheritance if you wanted to use one.
At the same time, because the AbstractModel contains a regular save function, you can’t directly integrate this plugin into it. The function is suitable for any model that fires the model save after an event, which is used to track changes in every inheritance that utilizes it.
Observers are also advantageous if you want to push a plugin’s limits. It will not work if you integrate a plugin to the parent class from which many additional classes are derived.
However, if the parent class creates an event, any entities derived from the event can take an action.
How Are Magento 2 Plugins Useful?
When comparing Magento 2 plugins vs observers, we find that Magento 2 plugins are more versatile than observers. They can modify the function of any Magento public method, except for virtual and final classes, final, static and non-public methods, constructors, and objects instantiated before bootstrapping Magento\Framework\Interception.
Unlike event observers, plugins can function everywhere in the system. They can be leveraged to change or override any Magento public method. Plugins are a core part of custom Magento eCommerce website development. New Magento updates do not have any effect on them.
Developers can write plugin-based code resistant to new Magento patches and provide all three methods, before, after, and around, to replace the original Magento 2 behavior when employed in conjunction with a stable public API, with the @api mark.
Since plugins can intercept the function before, during, and after the call, they are also known as interceptors. Using a plugin, you can change almost any function.
Magento developers can:
- Use Before plugins to edit input arguments
- Use After plugins to modify the function’s result
- Use Around plugins to completely change the function’s logic
In simple words, this means that plugins do not interfere with each other. They are typically called individually in a pre-set order, which prevents mutual disputes.
Moreover, plugins are used throughout the platform and can be applied for any public function. They are beneficial for extensions that need to intercept and modify public method behavior. However, using numerous plugins around a call leads to the growth of stack traces and poor site performance.
You can always hire Magento 2 developers if you face any Magento speed and performance optimization issues.
Which is the Right Tool for the Task?
Magento 1 offered limited possibilities for developers. If they needed to modify the behavior of the original code, they had to either construct observers to listen to specific events or manage with a clutter of preferences that could mess with each other’s values if the developer wasn’t careful enough.
However, with Magento 1 end of life, the era of event observers has passed. In Magento development services, observers are mainly used as a part of old code or in small applications.
There are a few drawbacks of being an event observer. Because Magento creates a minimum of three objects in response to the trigger event, observers are much slower than plugins. Observers offer less flexibility when adding platform-wide functionality. Event observers have key limits in that they must not change the objects they affect.
Remember that even with Magento 2 development, observers can still be useful. Setting up observers, just like in Magento 1, can be valuable if you want to add store-wide features like a reward system or bonus points for increasing sales.
However, it’s good to rely on plugins to accomplish the task. Individual event observers can be implemented for the front-end and adminhtml (with an events.xml file defining their field of application).
What and When to Use?
There are several areas in Magento 2’s core where observers play a vital role in changing the app’s behavior. Seeing the number of areas where observers work within Magento, getting rid of them will be very difficult.
However, observers will soon become outdated in the developer community in the future. But, that won’t happen until Magento 2 completely eliminates inheritance in favor of composition.
Here’s how you can choose a suitable tool for your task (ranked from best to worst):
- You should prefer plugins using @api methods over simple plugins. The Magento core development team will not often update @api methods, making them more reliable and future-ready.
- The next best option is to use event observers, especially if you know them from the Magento 1 development period.
- You should use non-@api plugins at last. They are less reliable than observers and do not have the advantages of @api plugins.
Wrapping Up
Are you finding it difficult to convert your third-party extensions from observers to plugins? Do you want to increase the performance and reliability of your Magento store? You can contact hire Magento 2 developers from us for custom Magento 2 module development services.
Being a leading provider of Magento development services, Magento India can help you scale your business in the competitive eCommerce landscape and update your Magento extensions with the right use of plugins. Get in touch with us to accelerate your eCommerce journey today.
FAQs
Q.1. Where can I find the best Magento extensions?
Ans. You can find reliable Magento extensions from the Magento marketplace. There are also some third-party Magento 2 module development companies that develop stable Magento extensions/modules.
Q.2. Can you add custom functionalities to my Magento store?
Ans. Yes, we can. We specialize in custom Magento extension development services and solutions to make your store stand out.
Q.3. I need to migrate my existing online store, on another platform, to Magento. Can you help?
Ans. Yes, of course. You can reach out to our experts for professional Magento 2 store migration services today!
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