Internal validator based on a JSON schema

Based on a JSON schema, ajv is used to create a validator object in Javascript that can be used to check a configuration. This is done in a QuickJS context (QuickJSR::JSContext), and stored inside the context property of the the object.

All YAML is parsed in R, so the validated data is what R reads:

• Files are read with yaml::read_yaml().

• S7schema objects are converted with to_yaml() and read back with yaml::yaml.load(), so the validated data matches what write_config() writes.

• list objects in validate_list() are validated as they are.

The resulting list is converted to JSON with jsonlite::toJSON() and validated by ajv. The JavaScript side never parses YAML. NA, NaN, and Inf values become null in the JSON sent to ajv. Numbers are sent with 17 significant digits, so numbers from files and lists are validated exactly. S7schema objects are validated as write_config() writes them, so numbers that need 17 significant digits (e.g. 0.1 + 0.2) are rounded.

See json-schema.org on how to specify a JSON schema.

Usage

validator(schema, call = rlang::caller_env())

Arguments

schema

character(1) path to a JSON schema.

call

The execution environment shown in error messages if the schema is invalid. See rlang::abort().

Value

New validator object

Properties

context

QuickJSR::JSContext with a validator object based on the schema