compileAsync does not loadSchema a schema that is $ref’d by a oneOf with a discriminator #2427
Description
What version of Ajv are you using? Does the issue happen if you use the latest version?
latest (8.13.0)
Ajv options object
const options = {
discriminator: true,
async loadSchema(url) {
console.log('loadSchema', url)
const name = url.substring("scheme://".length)
return schemas[name]
},
};JSON Schema
const schemas = {
main: {
type: "object",
discriminator: {propertyName: "foo"},
required: ["foo"],
oneOf: [
{
$ref: "scheme://schema1",
},
{
$ref: "scheme://schema2",
},
],
},
schema1: {
type: "object",
properties: {
foo: {const: "x"},
},
},
schema2: {
type: "object",
properties: {
foo: {enum: ["y", "z"]},
},
},
};Sample data
{"foo": "x"}Your code
const Ajv = require("ajv");
const ajv = new Ajv(options);
// If you uncomment this, then there is no error
// Object.entries(schemas).forEach(([id, schema]) => {
// ajv.addSchema(schema, 'scheme://' + id)
// })
async function main() {
const validate = await ajv.compileAsync(schemas.main)
validate(data)
}
main().catch((err) => console.log(err))Validation result, data AFTER validation, error messages
Error: discriminator: oneOf subschemas (or referenced schemas) must have "properties/foo"
What results did you expect?
No error
Are you going to resolve the issue?
Maybe if it is easy
Notes:
-
If you call
ajv.addSchema(i.e., uncomment the commented code), then the error goes away. Therefore, it is the resolving of the$refthat is the issue -
When
discriminator: true, thenloadSchemais not called. -
But if you set
discriminator: falseand remove thediscriminatorfromschema.main, thenloadSchemais called.loadSchema scheme://schema1 loadSchema scheme://schema2
My guess is that lib/vocabularies/discriminator/index.ts’s getMapping() needs to throw new MissingRefError so that _compileAsync can catch the error and load the missing schemas.