ZDDC/zddc/internal/jsonschema/schema.go
2026-06-11 13:32:31 -05:00

63 lines
3.7 KiB
Go

// Package jsonschema is a focused JSON Schema 2020-12 validator covering only
// the subset of keywords used by the form-data system. See validate.go for the
// supported keyword list. Unsupported keywords are silently ignored — the
// form-spec meta-schema enforces that authors only use the supported subset.
//
// This package is intentionally smaller than a full JSON Schema implementation
// (e.g. github.com/santhosh-tekuri/jsonschema). Match-implementation-cost-to-
// surface-used: the form system never needs $ref, oneOf/anyOf, if/then/else,
// or remote schema fetch in v0; reimplementing that machinery would be more
// code than the entire validator we ship here.
//
// When the v1+ form-spec adds those features, revisit this trade-off.
package jsonschema
// Schema is the in-memory representation of a JSON Schema. Fields use both
// YAML and JSON tags so the same struct round-trips through either encoding —
// form specs are authored in YAML, but data submissions arrive as JSON.
//
// Pointer-typed fields (Minimum, Maximum, MinLength, MaxLength) distinguish
// "unset" from "set to zero", which matters because zero is a valid bound.
//
// AdditionalProperties is `any` to accept either a bool (the v0-supported
// shape — only `false` is enforced; `true` and unset are both "allow") or a
// nested schema (parsed but not enforced in v0).
type Schema struct {
Type string `yaml:"type" json:"type,omitempty"`
Properties map[string]*Schema `yaml:"properties" json:"properties,omitempty"`
Required []string `yaml:"required" json:"required,omitempty"`
Items *Schema `yaml:"items" json:"items,omitempty"`
Enum []any `yaml:"enum" json:"enum,omitempty"`
Minimum *float64 `yaml:"minimum" json:"minimum,omitempty"`
Maximum *float64 `yaml:"maximum" json:"maximum,omitempty"`
MinLength *int `yaml:"minLength" json:"minLength,omitempty"`
MaxLength *int `yaml:"maxLength" json:"maxLength,omitempty"`
Pattern string `yaml:"pattern,omitempty" json:"pattern,omitempty"`
Format string `yaml:"format" json:"format,omitempty"`
AdditionalProperties any `yaml:"additionalProperties" json:"additionalProperties,omitempty"`
Title string `yaml:"title" json:"title,omitempty"`
Description string `yaml:"description" json:"description,omitempty"`
Default any `yaml:"default" json:"default,omitempty"`
// ReadOnly: if true, clients render this property as disabled and
// suppress edit affordances. Not enforced by the validator (a
// rejected write is the wrong UX for a read-only field — the
// server strips the value instead). Surface to clients via JSON.
ReadOnly bool `yaml:"readOnly,omitempty" json:"readOnly,omitempty"`
// Labels is an extension used by the form renderer to display a
// human label next to a code in enum-with-labels dropdowns. The
// key matches an entry in Enum; the value is the display label
// (e.g. {"ACM": "Acme Inc"}). Server-injected from the cascade's
// field_codes:codes map; not enforced by the validator.
Labels map[string]string `yaml:"x-labels,omitempty" json:"x-labels,omitempty"`
}
// Error reports a single validation failure. Path is a JSON Pointer (RFC 6901)
// pointing at the offending value within the validated document. Both fields
// flow through the form handler unchanged into the JSON response, so the
// browser-side renderer can locate and highlight the right widget.
type Error struct {
Path string `json:"path"`
Message string `json:"message"`
}