const form = formidable({
  multiples: false,
  uploadDir: environment.tmp_dir_avatars,
  maxFileSize: environment.max_avatar_size
});

async function validFile(req, res, next) {
  try {
    console.log("validFile");
    const file = await new Promise((resolve, reject) => {
      form.parse(req, (err, fields, decodedObject) => {
        if (err) {
          return reject(err);
        }
        const file = decodedObject.avatar;
        if (!file.type) {
          return reject({
            message: "File format doesnt exist " + file.type,
            file: file
          });
        }
        // image/x-png, image/png, image/gif, image/jpeg
        const fileType = file.type.toLowerCase();
        if (
          fileType === "image/x-png" ||
          fileType === "image/png" ||
          fileType === "image/gif" ||
          fileType === "image/jpeg"
        ) {
          console.log("readed file", file.name, "to", file.path);
          resolve(file);
        } else {
          reject({ message: "Wrong file format " + fileType, file: file });
        }
      });
    });
    res.locals.file = file;
    return next();
  } catch (err) {
    if (err.file && err.file.path) {
      // Delete file
      fs.unlink(err.file.path, err => {
        if (err) {
          console.error(err);
          return;
        }
      });
    }
    console.error("error validFile userId:", req.user.id, err.message);
    return res.json(requester.createError());
  }
}