JiriChara/krtek

import path from 'path';

import readFile from '../readFile';
import writeFile from '../writeFile';

/**
 * FileProvider stores a given string in the file on Linux file system.
 */
export default class FileProvider {
  constructor({
    folder = '/tmp'
  } = {}) {
    this.folder = folder;
  }

  /*
   * Get path to the file based on unique hash that is generated by Cache class based on JavaScript
   * string, query parameters and options passed to Krtek. Files will be stored in folder that is
   * passed to the constructor of FileProvider.
   */
  getFilePath(hash) {
    return path.resolve(
      this.folder,
      `krtek-${hash}.cache`
    );
  }

  /**
   * Cache given string in a file and call callback function when done.
   */
  set(hash, code) {
    const file = this.getFilePath(hash);

    return writeFile(file, code);
  }

  /**
   * Read content of the cached file.
   */
  get(hash) {
    const file = this.getFilePath(hash);

    return readFile(file);
  }
}