com.blockether.skjema.core — com.blockether/skjema 0.3.0

JSON Schema 2020-12 evaluation.

The evaluator answers ANNOTATIONS as well as errors, from the first line and not as a later addition: unevaluatedProperties and unevaluatedItems are defined in terms of what the ADJACENT keywords and the in-place applicators already evaluated, so a validator that answers only true/false cannot grow them without being rewritten. Every evaluation therefore returns {:valid? :props :items :errors} - the property names and item indices that were evaluated AT THIS INSTANCE LOCATION, plus every fault found underneath.

Two kinds of applicator, and the difference is the whole design:

• IN PLACE ($ref, $dynamicRef, allOf, anyOf, oneOf, if/then/ else, dependentSchemas) apply another schema to the SAME instance location, so their annotations belong to this location and bubble up.
• CHILD (properties, patternProperties, additionalProperties, items, prefixItems, contains, propertyNames) apply to a location BELOW, so their annotations stay there and this location records only which member was covered.

Identifiers are resolved once, when the schema is compiled: $id moves the base URI, $anchor and $dynamicAnchor name a place inside it, and the index that comes out is what $ref and $dynamicRef read. Nothing is fetched over the network, ever - a schema that references a document the caller did not supply is a compile error, not a silent pass.

compile-schema clj

(compile-schema schema)

(compile-schema schema opts)

Compile and index a schema once so repeated validation does not walk its structure. Options: :base, :registry, and :format-assertion. Referenced documents are resolved only from the supplied registry.

compiled-schema? clj

(compiled-schema? x)

explain clj

(explain schema instance)

(explain schema instance opts)

Nil when instance satisfies the schema, otherwise JSON Schema BASIC output - {:valid false :errors [...]} - where every error keeps its instance and keyword locations and adds :keyword plus keyword-specific :params, so a caller can render or act on it without parsing the human :error string. The entire answer is a JSON value.

explainer clj

(explainer schema)

(explainer schema opts)

The reasons as a bare function of the instance: nil when it validates, else JSON Schema BASIC output. The counterpart of validator for the same schema.

read-schema clj

(read-schema source)

Read a JSON Schema from JSON text, a Path, File, URL/resource, InputStream, or Reader. Objects keep their JSON string keys.

validate clj

(validate schema instance)

(validate schema instance opts)

True when instance satisfies the schema. validator is the same answer without the per-call dispatch.

validator clj

(validator schema)

(validator schema opts)

The verdict as a bare function of the instance. It closes over the compiled predicate, so a call reaches it without a map lookup - take this when the same schema validates more than once. Evaluation stops at the first keyword that refuses and no error is built on the way.

write-schema clj

(write-schema value)

Render a schema or validation result as compact JSON.