Enhance CI: Adding ERB Linter For Robust Code Quality

Nov 30, 2025 by Alex Johnson 54 views

Enhancing CI Pipeline: Integrating ERB Linter for Improved Code Quality

In this article, we'll walk through the process of adding an ERB (Embedded Ruby) linter to our Continuous Integration (CI) pipeline. This enhancement is crucial for maintaining code quality and preventing common issues in ERB/HTML templates. We'll cover the importance of ERB linting, the steps taken to implement it, and the benefits it brings to the rubyforgood/stocks-in-the-future project. By integrating the ERB linter, we aim to automate the detection of malformed HTML tags, invalid ERB syntax, and other HTML violations, ensuring a more robust and reliable codebase.

Why ERB Linting is Essential

ERB linting is a critical practice in modern web development, particularly for projects that heavily rely on ERB templates. ERB, or Embedded Ruby, is a templating system that allows Ruby code to be embedded within HTML documents. While ERB offers great flexibility, it also introduces the potential for errors such as malformed HTML tags, invalid syntax, and other common HTML violations. These issues, if left unchecked, can lead to rendering problems, broken layouts, and even security vulnerabilities.

Catching these errors manually can be challenging and time-consuming. Developers often need to scrutinize code line by line, trying to identify subtle mistakes that can be easily overlooked. This process is not only inefficient but also prone to human error. An automated ERB linter, on the other hand, can automatically detect these issues, saving developers valuable time and effort. By integrating an ERB linter into our CI pipeline, we can ensure that every code change is automatically checked for these common problems, providing an additional layer of quality assurance.

Moreover, the benefits of ERB linting extend beyond just error detection. By enforcing consistent coding standards and best practices, an ERB linter helps to improve the overall maintainability and readability of the codebase. This is particularly important for collaborative projects, where multiple developers may be working on the same code. A consistent code style makes it easier to understand and modify the code, reducing the risk of introducing new errors. In the context of the rubyforgood/stocks-in-the-future project, which is a collaborative effort aimed at building financial tools for social good, maintaining a high level of code quality and consistency is paramount. By adding an ERB linter to our CI pipeline, we are taking a proactive step towards ensuring the long-term health and sustainability of the project.

Steps to Enable ERB Linting

Enabling ERB linting in our project involved a series of carefully planned steps. First, we added the ERB linter to our development environment, ensuring that it could be run locally by developers. This initial step was crucial for identifying any existing issues in our codebase and establishing a baseline for future development. The addition of the ERB linter was tracked in this GitHub issue.

Once the linter was added, the next step was to address all existing issues identified by the linter. This involved systematically reviewing the codebase and fixing any malformed HTML tags, invalid ERB syntax, or other violations of HTML standards. This was a significant undertaking, but it was essential for ensuring that the linter could be effectively integrated into our CI pipeline. The resolution of these initial issues was documented in this GitHub issue.

With the initial issues resolved, we were then ready to integrate the ERB linter into our CI pipeline. This involved configuring our CI system to automatically run the linter on every code change. By adding the linter to the CI pipeline, we ensure that new issues are caught early in the development process, before they can make their way into production. This proactive approach to quality assurance is key to maintaining a healthy and reliable codebase.

Implementation Details: How We Integrated the ERB Linter

To effectively integrate the ERB linter into our CI pipeline, we followed a specific set of steps, ensuring that the linter runs smoothly and provides valuable feedback on our code. The first step was to understand how to run the ERB linter locally. This is crucial for developers to be able to test their code before pushing it to the repository. Detailed instructions on how to run the ERB linter can be found in our CONTRIBUTING.md file. This documentation provides a clear and concise guide for developers, ensuring that everyone on the team can easily run the linter.

Next, we examined our existing CI linter script to determine the best place to add the ERB linter check. The CI linter script, located in our repository, is responsible for running various checks on our code, including RuboCop and security audits. To ensure that the ERB linter provides the most value, we decided to add it after RuboCop and before the security audits. This placement allows us to catch ERB-related issues before more intensive security checks are performed, streamlining the CI process.

The specific line in our CI linter script where the ERB linter is invoked can be found here. By adding the ERB linter to this location, we ensure that it is automatically run as part of our CI pipeline, providing continuous feedback on the quality of our ERB templates. This integration is a key step in our commitment to maintaining a high-quality codebase.

To summarize, the implementation involved:

Understanding how to run the ERB linter locally.
Locating the CI linter script.
Adding the ERB linter check in the appropriate sequence (after RuboCop and before security audits).

Acceptance Tests: Ensuring the ERB Linter Works as Expected

To ensure that the ERB linter is functioning correctly within our CI pipeline, we established a set of acceptance tests. These tests are designed to verify that the linter runs in the correct order, flags ERB/HTML errors, and allows the CI pipeline to pass when no errors are present. These tests provide confidence in the linter's functionality and ensure that it is effectively contributing to our code quality efforts.

The first acceptance test verifies that the ERB linter runs in CI after RuboCop and before the security audits. This is crucial for ensuring that the linter is integrated into the pipeline in the correct sequence. By running the linter in this order, we can catch ERB-related issues early in the process, before more intensive security checks are performed. This helps to streamline the CI process and provide timely feedback to developers.

The second acceptance test focuses on error detection. Specifically, this test ensures that when an ERB/HTML error is introduced, the CI build fails with a clear error message from the ERB linter. This is a critical test, as it verifies that the linter is effectively flagging issues in our codebase. The clear error message is also important, as it provides developers with the information they need to quickly identify and fix the problem.

The final acceptance test checks for the absence of errors. This test ensures that the CI pipeline passes when no ERB/HTML errors are present. This is an important test, as it verifies that the linter is not generating false positives and that our codebase is free from ERB-related issues. By passing this test, we can have confidence in the quality of our ERB templates and the overall health of our codebase.

Conclusion

Integrating an ERB linter into our CI pipeline is a significant step towards maintaining code quality and preventing common ERB/HTML issues. By automating the detection of malformed HTML tags, invalid ERB syntax, and other HTML violations, we can save valuable time and effort while ensuring a more robust and reliable codebase. The steps we took, from adding the ERB linter to addressing existing issues and configuring the CI pipeline, demonstrate our commitment to code quality and best practices. The acceptance tests we established further validate the linter's functionality and provide confidence in its ongoing contribution to our project.

For more information on ERB linting and best practices in Ruby development, consider exploring resources like the Ruby Style Guide. This guide offers valuable insights into writing clean, maintainable, and high-quality Ruby code, complementing the benefits of ERB linting and enhancing overall code quality.