@comyata/fe/Importer/FileImporter.js

Execute YAML and JSON files like programs and get clean data to work with as result.

import { convert } from '@comyata/fe/Converter';
import { extname } from '@comyata/fe/Helpers/extname';
import fs from 'node:fs';
import path from 'node:path';
import util from 'node:util';
import url from 'node:url';
import yaml from 'yaml';
export const fileImporter = ({
  basePath,
  converter,
  converterDefault,
  readFile = util.promisify(fs.readFile)
}) => {
  const importerId = 'file';
  const convertDefault = converterDefault ||= value => yaml.parse(value);
  const resolveContext = dir => {
    const absPath = url.fileURLToPath(dir);
    const relPath = path.relative(basePath, absPath);
    if (relPath.startsWith('../') || relPath.startsWith('..\\')) {
      throw new Error(`File import ${JSON.stringify(dir)} not relative to ${JSON.stringify(basePath)}`);
    }
    return {
      importer: importerId,
      resolveRelative: relPath => url.pathToFileURL(path.join(absPath, relPath)).href
    };
  };
  const resolveFileContext = fileUrl => {
    const filePath = url.fileURLToPath(fileUrl);
    const relPath = path.relative(basePath, filePath);
    if (relPath.startsWith('../') || relPath.startsWith('..\\')) {
      throw new Error(`File import ${JSON.stringify(fileUrl)} not relative to ${JSON.stringify(basePath)}`);
    }
    return {
      load: () => {
        return readFile(filePath).then(b => convert(converter, convertDefault, {
          ext: extname(relPath).toLowerCase(),
          url: fileUrl
        })(b.toString()));
      },
      ...resolveContext(url.pathToFileURL(path.dirname(filePath)).href)
    };
  };
  return {
    id: importerId,
    // todo: add base path to file scope??
    scopes: ['file://'],
    resolveDirectory: resolveContext,
    resolveFile: resolveFileContext
  };
};