@sinclair/typebox
Version:
Json Schema Type Builder with Static Type Resolution for TypeScript
173 lines (172 loc) • 7.53 kB
JavaScript
import { Check } from '../check/index.mjs';
import { Clone } from '../clone/index.mjs';
import { Deref, Pushref } from '../deref/index.mjs';
import { Kind } from '../../type/symbols/index.mjs';
// ------------------------------------------------------------------
// ValueGuard
// ------------------------------------------------------------------
import { IsArray, IsDate, IsFunction, IsObject, IsUndefined, HasPropertyKey } from '../guard/index.mjs';
// ------------------------------------------------------------------
// TypeGuard
// ------------------------------------------------------------------
import { IsKind } from '../../type/guard/kind.mjs';
// ------------------------------------------------------------------
// ValueOrDefault
// ------------------------------------------------------------------
function ValueOrDefault(schema, value) {
const defaultValue = HasPropertyKey(schema, 'default') ? schema.default : undefined;
const clone = IsFunction(defaultValue) ? defaultValue() : Clone(defaultValue);
return IsUndefined(value) ? clone : IsObject(value) && IsObject(clone) ? Object.assign(clone, value) : value;
}
// ------------------------------------------------------------------
// HasDefaultProperty
// ------------------------------------------------------------------
function HasDefaultProperty(schema) {
return IsKind(schema) && 'default' in schema;
}
// ------------------------------------------------------------------
// Types
// ------------------------------------------------------------------
function FromArray(schema, references, value) {
// if the value is an array, we attempt to initialize it's elements
if (IsArray(value)) {
for (let i = 0; i < value.length; i++) {
value[i] = Visit(schema.items, references, value[i]);
}
return value;
}
// ... otherwise use default initialization
const defaulted = ValueOrDefault(schema, value);
if (!IsArray(defaulted))
return defaulted;
for (let i = 0; i < defaulted.length; i++) {
defaulted[i] = Visit(schema.items, references, defaulted[i]);
}
return defaulted;
}
function FromDate(schema, references, value) {
// special case intercept for dates
return IsDate(value) ? value : ValueOrDefault(schema, value);
}
function FromImport(schema, references, value) {
const definitions = globalThis.Object.values(schema.$defs);
const target = schema.$defs[schema.$ref];
return Visit(target, [...references, ...definitions], value);
}
function FromIntersect(schema, references, value) {
const defaulted = ValueOrDefault(schema, value);
return schema.allOf.reduce((acc, schema) => {
const next = Visit(schema, references, defaulted);
return IsObject(next) ? { ...acc, ...next } : next;
}, {});
}
function FromObject(schema, references, value) {
const defaulted = ValueOrDefault(schema, value);
// return defaulted
if (!IsObject(defaulted))
return defaulted;
const knownPropertyKeys = Object.getOwnPropertyNames(schema.properties);
// properties
for (const key of knownPropertyKeys) {
// note: we need to traverse into the object and test if the return value
// yielded a non undefined result. Here we interpret an undefined result as
// a non assignable property and continue.
const propertyValue = Visit(schema.properties[key], references, defaulted[key]);
if (IsUndefined(propertyValue))
continue;
defaulted[key] = Visit(schema.properties[key], references, defaulted[key]);
}
// return if not additional properties
if (!HasDefaultProperty(schema.additionalProperties))
return defaulted;
// additional properties
for (const key of Object.getOwnPropertyNames(defaulted)) {
if (knownPropertyKeys.includes(key))
continue;
defaulted[key] = Visit(schema.additionalProperties, references, defaulted[key]);
}
return defaulted;
}
function FromRecord(schema, references, value) {
const defaulted = ValueOrDefault(schema, value);
if (!IsObject(defaulted))
return defaulted;
const additionalPropertiesSchema = schema.additionalProperties;
const [propertyKeyPattern, propertySchema] = Object.entries(schema.patternProperties)[0];
const knownPropertyKey = new RegExp(propertyKeyPattern);
// properties
for (const key of Object.getOwnPropertyNames(defaulted)) {
if (!(knownPropertyKey.test(key) && HasDefaultProperty(propertySchema)))
continue;
defaulted[key] = Visit(propertySchema, references, defaulted[key]);
}
// return if not additional properties
if (!HasDefaultProperty(additionalPropertiesSchema))
return defaulted;
// additional properties
for (const key of Object.getOwnPropertyNames(defaulted)) {
if (knownPropertyKey.test(key))
continue;
defaulted[key] = Visit(additionalPropertiesSchema, references, defaulted[key]);
}
return defaulted;
}
function FromRef(schema, references, value) {
return Visit(Deref(schema, references), references, ValueOrDefault(schema, value));
}
function FromThis(schema, references, value) {
return Visit(Deref(schema, references), references, value);
}
function FromTuple(schema, references, value) {
const defaulted = ValueOrDefault(schema, value);
if (!IsArray(defaulted) || IsUndefined(schema.items))
return defaulted;
const [items, max] = [schema.items, Math.max(schema.items.length, defaulted.length)];
for (let i = 0; i < max; i++) {
if (i < items.length)
defaulted[i] = Visit(items[i], references, defaulted[i]);
}
return defaulted;
}
function FromUnion(schema, references, value) {
const defaulted = ValueOrDefault(schema, value);
for (const inner of schema.anyOf) {
const result = Visit(inner, references, Clone(defaulted));
if (Check(inner, references, result)) {
return result;
}
}
return defaulted;
}
function Visit(schema, references, value) {
const references_ = Pushref(schema, references);
const schema_ = schema;
switch (schema_[Kind]) {
case 'Array':
return FromArray(schema_, references_, value);
case 'Date':
return FromDate(schema_, references_, value);
case 'Import':
return FromImport(schema_, references_, value);
case 'Intersect':
return FromIntersect(schema_, references_, value);
case 'Object':
return FromObject(schema_, references_, value);
case 'Record':
return FromRecord(schema_, references_, value);
case 'Ref':
return FromRef(schema_, references_, value);
case 'This':
return FromThis(schema_, references_, value);
case 'Tuple':
return FromTuple(schema_, references_, value);
case 'Union':
return FromUnion(schema_, references_, value);
default:
return ValueOrDefault(schema_, value);
}
}
/** `[Mutable]` Generates missing properties on a value using default schema annotations if available. This function does not check the value and returns an unknown type. You should Check the result before use. Default is a mutable operation. To avoid mutation, Clone the value first. */
export function Default(...args) {
return args.length === 3 ? Visit(args[0], args[1], args[2]) : Visit(args[0], [], args[1]);
}