// @ts-ignore
import Validator from '@adobe/structured-data-validator';
import * as cheerio from 'cheerio';
/**
* Result of a structured data (schema) validation check.
*/
export interface ValidationResult {
/** Whether all schemas were found and valid. */
valid: boolean;
/** A list of validation errors found across all detected schemas. */
errors: any[];
/** The original JSON-LD schemas extracted from the input. */
schemas: any[];
}
/**
* Validates structured data (JSON-LD) from a URL, raw HTML, or a JSON string.
*
* @param input - The source to validate (URL, HTML string, or JSON string).
* @param type - The type of input being provided.
* @returns A result object indicating validity and listing any errors found.
*/
export async function validateSchema(
input: string,
type: 'url' | 'html' | 'json'
): Promise<ValidationResult> {
let schemas: any[] = [];
const errors: any[] = [];
try {
if (type === 'url') {
try {
const response = await fetch(input);
if (!response.ok) {
throw new Error(`Failed to fetch URL: ${response.status} ${response.statusText}`);
}
const html = await response.text();
schemas = extractSchemas(html);
} catch (e: any) {
return { valid: false, errors: [`Fetch error: ${e.message}`], schemas: [] };
}
} else if (type === 'html') {
schemas = extractSchemas(input);
} else if (type === 'json') {
try {
const parsed = JSON.parse(input);
schemas = Array.isArray(parsed) ? parsed : [parsed];
} catch (e: any) {
return { valid: false, errors: [`JSON Parse error: ${e.message}`], schemas: [] };
}
}
if (schemas.length === 0) {
return { valid: false, errors: ["No structured data (JSON-LD) found"], schemas: [] };
}
const validator = new Validator();
const validationPromises = schemas.map(async (schema) => {
try {
let type = schema['@type'];
if (Array.isArray(type)) {
type = type[0];
}
const wrapper = {
jsonld: {
[type || 'Thing']: [schema]
}
};
const result = await validator.validate(wrapper);
if (result && Array.isArray(result) && result.length > 0) {
// result is array of errors
return result.map((err: any) => ({
...err,
schemaType: schema['@type'] || 'Unknown'
}));
}
return [];
} catch (e: any) {
return [{ message: `Validation exception: ${e.message}`, schemaType: schema['@type'] || 'Unknown' }];
}
});
const results = await Promise.all(validationPromises);
errors.push(...results.flat());
return {
valid: errors.length === 0,
errors,
schemas
};
} catch (err: any) {
return { valid: false, errors: [err.message], schemas: [] };
}
}
function extractSchemas(html: string): any[] {
const $ = cheerio.load(html);
const schemas: any[] = [];
$('script[type="application/ld+json"]').each((_, el) => {
try {
const content = $(el).html();
if (content) {
const parsed = JSON.parse(content);
if (Array.isArray(parsed)) {
schemas.push(...parsed);
} else {
schemas.push(parsed);
}
}
} catch (e) {
// ignore invalid json blocks
}
});
return schemas;
}
