If you’re working with YAML files, you’ll instinctively hit tab even though it is strictly forbidden. Apps will often choke on malformed YAML and debugging borked configuration settings (staring at you here, symfony) isn’t a picnic either. Luckily, there’s a solution: the wonderful online YAML parser!
Oddly, the YAML homepage does not have a built in YAML validator, at least none that I can see. A search for a working YAML Validator will yield this very helpful Stack Overflow page asking for YAML validation. One of the suggestions, by Paul Tarjan is the excellent Online YAML Parser!
The Online YAML Parser gives you three options: converting YAML to json, python or canonical yaml. My perference is JSON, but any of them succeeding in converting the YAML will do. If there is an error (like a hidden tab, or an unclosed bracket) there will be an alert with the line and column numbers. Here’s an example of the converted YAML from one my config-files for an app.
So if you need to validate your YAML before you try to give it to your application – and you’re writing it by hand, checkout the YAML validator, well, parser!