👀 Views: 21 💬 Answers: 1 📅 Created: 2025-09-06

regex api validation JavaScript

I'm integrating two systems and I'm stuck on something that should probably be simple... Building an application that interfaces with several third-party APIs, I've come across the need to validate API keys before making requests. The API keys in question typically start with the prefix `API_` followed by a series of alphanumeric characters, which can vary in length but generally should be between 16 to 32 characters. The challenge I’m facing is constructing a regex pattern that handles both the presence of the `API_` prefix and the varying lengths of the key. My first attempt used the following regex: ```regex ^API_[A-Za-z0-9]{16,32}$ ``` However, this only matches keys that start with `API_`. I need to also account for cases where the key might not have this prefix. So, I modified my regex to: ```regex ^(API_)?[A-Za-z0-9]{16,32}$ ``` This change works for the prefix, but the requirement is that if the prefix is omitted, the key should still be between 16 to 32 characters long. To clarify further, I'm looking for a regex pattern that allows both of these formats: - `API_1234567890abcdef` - `1234567890abcdef12345678` I've also tried using `(?:API_)?` to make the prefix optional but that approach didn’t yield the expected results during testing. Additionally, after implementing this regex, performance becomes a concern as the application scales. I’d appreciate any recommendations on optimizing this further or any alternative patterns that might fit better. Lastly, if there are any tools or libraries in popular frameworks like Express.js that could complement regex validation for API keys, that would be helpful to know as well. For context: I'm using Javascript on Linux. What am I doing wrong? What's the best practice here? This is happening in both development and production on Windows 10. Thanks, I really appreciate it!