The expected configuration file format by default is json, but KrakenD can parse different formats if one of the following extensions is found:
.json.toml.yaml.yml.properties.props.prop.hcl
Nevertheless, our recommendation is to choose JSON.
Validate the syntax (not the logic) with krakend check
Why choosing json?
You are free to choose YAML, TOML or any of the other formats at your best convenience. But have in mind the following logic when choosing a file format other than json.
Using the UI: If you intend to generate or edit your configuration file using the KrakenDesigner, the input and output are always a .json file.
Flexible Configuration: If you want to split the configuration file into different pieces or use variables inside the configuration, the flexible configuration needs JSON.
Documentation: All our examples in the documentation and repositories are today shown in JSON format, so it’s always more convenient to reuse snippets of code.