@nu-art/schema-to-types/schema-to-types.js

schema-to-types - Express & Typescript based backend framework

// schema-to-types.ts
import * as fs from 'node:fs';
import * as path from 'node:path';
import $RefParser from '@apidevtools/json-schema-ref-parser';
import { FetchingJSONSchemaStore, InputData, JSONSchemaInput, quicktype, TypeScriptTargetLanguage, } from 'quicktype-core';
/**
 * Generate TypeScript defs from a JSON Schema file.
 * - Bundles all external $refs into a single schema object
 * - Emits only type/interface declarations (no runtime helpers)
 */
const generateTypeScriptType = async (inputPath, outputPath) => {
    // Inline external refs but keep internal $ref to avoid cycles
    const bundledSchema = await $RefParser.bundle(path.resolve(inputPath));
    const topLevelName = inferTopLevelName(outputPath, inputPath);
    const schemaInput = new JSONSchemaInput(new FetchingJSONSchemaStore());
    await schemaInput.addSource({
        name: topLevelName,
        schema: JSON.stringify(bundledSchema),
    });
    const inputData = new InputData();
    inputData.addInput(schemaInput);
    const { lines } = await quicktype({
        inputData,
        lang: new TypeScriptTargetLanguage(),
        rendererOptions: { 'just-types': 'true' }, // <= only types/interfaces
    });
    const ts = [
        `// Generated from ${path.basename(inputPath)} — do not edit by hand.`,
        `// ${new Date().toISOString()}`,
        '',
        ...lines,
        '',
    ].join('\n');
    const outputDir = path.dirname(outputPath);
    if (!fs.existsSync(outputDir))
        fs.mkdirSync(outputDir, { recursive: true });
    fs.writeFileSync(outputPath, ts, 'utf8');
};
function inferTopLevelName(outputPath, fallbackPath) {
    const base = path.basename(outputPath || fallbackPath).replace(/\.(d\.)?tsx?$/i, '').trim();
    const name = base.replace(/[^A-Za-z0-9_$]/g, '_'); // best-effort valid TS identifier
    return name.length ? name : 'Schema';
}
export const processConfig = async (configPath) => {
    const config = JSON.parse(fs.readFileSync(configPath, 'utf8'));
    for (const { input, output } of config) {
        await generateTypeScriptType(input, output);
    }
};