Fixing Deprecated Functionality In EndpointAbstract.php Mollie Magento

July 27, 2025 by StackCamp Team 71 views

EndpointAbstract.php - Deprecated Functionality Discussion

Hey guys,

I ran into a bit of a snag with the Mollie integration in Magento and wanted to share the issue and the fix I implemented. Hopefully, this can help someone else out there and maybe even make its way into a future release! We're talking about a deprecated functionality error in EndpointAbstract.php, so let's dive right in.

The Issue: Deprecated Functionality

So, the error I was getting looks like this:

2025-07-27T08:19:03+00:00 ERR (3): Deprecated functionality: Optional parameter $from declared before required parameter $filters is implicitly treated as a required parameter in /lib/Mollie/Mollie/src/Endpoints/EndpointAbstract.php on line 144
2025-07-27T08:19:03+00:00 ERR (3): Deprecated functionality: Optional parameter $limit declared before required parameter $filters is implicitly treated as a required parameter in /lib/Mollie/Mollie/src/Endpoints/EndpointAbstract.php on line 0

Basically, PHP is telling us that the way the $from and $limit parameters are defined in the rest_list function within EndpointAbstract.php is deprecated. This is because they are optional parameters declared before the required $filters parameter. PHP implicitly treats these optional parameters as required, which can lead to unexpected behavior and, well, deprecated functionality warnings!

Understanding Deprecated Functionality

Before we get into the fix, let's quickly touch on what "deprecated" means. When something is deprecated in programming, it means it's still working for now, but it's essentially on its way out. The developers are signaling that this particular feature or function is no longer the preferred way of doing things and might be removed entirely in a future version. Ignoring deprecation warnings can lead to headaches down the line when you upgrade your software and things suddenly break. So, it's always best to address them when you see them.

Digging into the Code

The error messages point us directly to EndpointAbstract.php, which is a core part of the Mollie API client library. This library is what allows Magento (or any other PHP application) to communicate with Mollie's payment processing platform. The EndpointAbstract.php file likely contains abstract methods or base implementations for various API endpoints, like retrieving lists of payments, refunds, or customers. The rest_list function, in particular, seems to be responsible for fetching collections of objects from the Mollie REST API.

The Importance of Proper Parameter Ordering

In PHP, the order in which you define function parameters matters. Required parameters (those without default values) must come after optional parameters (those with default values). This is because when you call a function, PHP fills in the parameters from left to right. If you have an optional parameter before a required one, PHP might get confused about which arguments you're actually passing.

In our case, the original function signature probably looked something like this:

protected function rest_list($from = null, $limit = null, array $filters)
{
    // ...
}

See the problem? $from and $limit are optional (they have default values of null), but $filters is required. This is a no-no in PHP land!

The Solution: Reordering and Merging Parameters

Okay, so how did I fix it? Here's the code snippet I used:

/**
 * Get a collection of objects from the REST API.
 *
 * @param string $from The first resource ID you want to include in your list.
 * @param int $limit
 * @param array $filters
 *
 * @return BaseCollection
 * @throws ApiException
 */
protected function rest_list($from = null, $limit = null, array $filters = [])
{
    $filters = array_merge(["from" => $from, "limit" => $limit], $filters);

    $apiPath = $this->getResourcePath() . $this->buildQueryString($filters);

    $result = $this->client->performHttpCall(self::REST_LIST, $apiPath);

    /** @var BaseCollection $collection */
    $collection = $this->getResourceCollectionObject($result->count, $result->_links);

    foreach ($result->_embedded->{$collection->getCollectionResourceName()} as $dataResult) {
        $collection[] = ResourceFactory::createFromApiResult($dataResult, $this->getResourceObject());
    }

    return $collection;
}

Let's break down what's happening here:

Made $filters Optional: The most crucial change is adding a default value ([], an empty array) to the $filters parameter. This makes it an optional parameter, which is perfectly fine since it's the last parameter in the list. The function definition now looks like this:
```
protected function rest_list($from = null, $limit = null, array $filters = [])
```
Merging Parameters: Inside the function, I'm using array_merge to combine the $from and $limit parameters into the $filters array. This is a neat way to handle these optional parameters. We're essentially taking the $from and $limit values (if they're provided) and adding them as key-value pairs to the $filters array.
```
$filters = array_merge(["from" => $from, "limit" => $limit], $filters);
```
For example, if $from was "resource123" and $limit was 5, the $filters array would become something like ["from" => "resource123", "limit" => 5, ...other filters...].
Building the API Path: The rest of the function logic remains the same. We're building the API path using the (now combined) $filters array, making the HTTP call to the Mollie API, and processing the results.

Why This Works

This solution addresses the deprecated functionality issue by ensuring that optional parameters are declared after required parameters. It also provides a clean way to handle the $from and $limit parameters by merging them into the $filters array. This makes the function more flexible and easier to use, as you can now pass $from and $limit directly as separate arguments or include them within the $filters array – whatever suits your needs!

Why This Matters: Clean Code and Future-Proofing

Fixing deprecated functionality might seem like a small thing, but it's crucial for maintaining clean, maintainable code. By addressing these warnings, we're ensuring that our code is compatible with future versions of PHP and the Mollie API client library. We're also making our code more readable and easier to understand, which is a huge win for collaboration and long-term project health.

The Importance of Staying Up-to-Date

In the world of software development, things are constantly evolving. New versions of programming languages, libraries, and frameworks are released regularly, often with improvements, bug fixes, and yes, deprecations. Staying up-to-date with these changes is essential for security, performance, and compatibility. Ignoring deprecation warnings is like ignoring the check engine light in your car – it might run for a while, but eventually, something's going to break down.

Contributing to Open Source

I'm sharing this solution not just to help others who might be facing the same issue, but also to highlight the importance of contributing to open-source projects. If you find a bug or a way to improve a library, don't hesitate to share your solution! Submitting a pull request (PR) with your fix is a fantastic way to give back to the community and help make the software we all rely on even better. Who knows, maybe my fix will make it into the next release of the Mollie API client library!

The Call to Action: Implementation in a New Release

So, this is where I'm hoping the Mollie team (or anyone else maintaining the library) might take notice. This fix seems to resolve the deprecated functionality warning without breaking any existing functionality. It would be fantastic to see this implemented in a new release of the Mollie API client library for Magento. This would help ensure that everyone using the library is running on code that's up-to-date and free of deprecation warnings.

How to Submit a Pull Request

If you're not familiar with submitting pull requests, it's a valuable skill to learn! Most open-source projects use platforms like GitHub or GitLab for code management and collaboration. Here's a general overview of the process:

Fork the Repository: Create your own copy of the repository on the platform (e.g., GitHub). This allows you to make changes without affecting the original project.
Create a Branch: Create a new branch in your forked repository for your changes. This keeps your changes isolated and makes it easier to submit a PR.
Make Your Changes: Implement your fix or feature in your branch.
Commit Your Changes: Commit your changes with clear and concise commit messages.
Push Your Branch: Push your branch to your forked repository.
Create a Pull Request: On the platform, create a pull request from your branch to the main repository. This notifies the project maintainers that you have changes to contribute.
Review and Discussion: The project maintainers will review your PR and might provide feedback or ask for changes. Be prepared to discuss your changes and make adjustments as needed.
Merge: If your PR is approved, the maintainers will merge your changes into the main repository.

Submitting a PR can seem daunting at first, but it's a rewarding experience! You're not only helping to improve the software, but you're also learning valuable skills and contributing to the open-source community.

Conclusion: Let's Keep Things Up-to-Date

This little adventure with the deprecated functionality in EndpointAbstract.php highlights the importance of staying vigilant about code quality and keeping our software up-to-date. By addressing these warnings and contributing to open-source projects, we can all help create a more robust and reliable software ecosystem. Hopefully, this fix will make its way into a future release, and we can all breathe a little easier knowing our Mollie integrations are running smoothly!

The Power of Community

Ultimately, the strength of the open-source community lies in collaboration and shared knowledge. By sharing our experiences, solutions, and insights, we can collectively overcome challenges and build better software. So, if you encounter a similar issue or have a fix to share, don't hesitate to speak up! Your contribution, no matter how small, can make a big difference.

Let me know if you guys have run into this issue or have any other thoughts on it!