Working with YAML files

Makefile.yaml has checked syntax before it is parsed by RKD. A jsonschema library was used to validate YAML files against a JSON formatted schema file.

This gives the early validation of typing inside of YAML files, and a clear message to the user about place where the typo is.

YAML parsing API

Schema validation is a part of YAML parsing, the preferred way of working with YAML files is to not only parse the schema but also validate. In result of this there is a class that wraps yaml library - rkd.yaml_parser.YamlFileLoader, use it instead of plain yaml library.

Notice: The YAML and schema files are automatically searched in .rkd, .rkd/schema directories, including RKD_PATH

Example usage:

from rkd.yaml_parser import YamlFileLoader

parsed = YamlFileLoader([]).load_from_file('deployment.yml', 'org.riotkit.harbor/deployment/v1')

FAQ

  1. FileNotFoundError: Schema “my-schema-name.json” cannot be found, looked in: [’…/riotkit-harbor’, ‘/…/riotkit-harbor/schema’, ‘/…/riotkit-harbor/.rkd/schema’, ‘/home/…/.rkd/schema’, ‘/usr/lib/rkd/schema’, ‘/usr/lib/python3.8/site-packages/rkd/internal/schema’]

The schema file cannot be found, the name is invalid or file missing. The schema should be placed somewhere in the .rkd/schema directory - in global, in home directory or in project.

  1. rkd.exception.YAMLFileValidationError: YAML schema validation failed at path “tasks” with error: [] is not of type ‘object’

It means you created a list (starts with “-”) instead of dictionary at “tasks” path.

Example what went wrong:

tasks:
    - description: first
    - description: second

Example how it should be as an ‘object’:

tasks:
    first:
        description: first

    second:
        description: second

API

class rkd.yaml_parser.YamlFileLoader(paths: List[str])

YAML loader extended by schema validation support

YAML schema is stored as JSON files in .rkd/schema directories. The Loader looks in all paths defined in RKD_PATH as well as in paths provided by ApplicationContext

find_path_by_name(filename: str, subdir: str) → str

Find schema in one of RKD directories or in current path

load(stream, schema_name: str)

Loads a YAML, validates and return parsed as dict/list

load_from_file(filename: str, schema_name: str)

Loads a YAML file from given path, a wrapper to load()