shelftest.handlers.dart

gistfile1.dart

library shelftest.handlers;

import 'dart:async';
import 'dart:convert';
import 'dart:io' show HttpHeaders;

import 'database.dart';
import 'user.dart';

import 'package:shelf_exception_response/exception.dart';
import 'package:shelf/shelf.dart' as shelf;
import 'package:shelf_path/shelf_path.dart';

const Map headers = const {HttpHeaders.CONTENT_TYPE: 'application/json'};

/**
 * Extract the 'name' value from the JSON decoded [body].
 *
 * Throw [BadRequestException] if [body] cannot decode to JSON.
 */
String _getUserName(String body) {
  try {
    return JSON.decode(body)['name'];
  } catch (_) {
    throw new BadRequestException({'error':'body malformed'});
  }
}

/**
 * Extract the 'userid' GET path parameter from [request].
 *
 * Throw [BadRequestException] if 'userid' is not an integer.
 */
int _getUserId(shelf.Request request) {
  try {
    return int.parse(getPathParameter(request, 'userid'));
  } catch(_) {
    throw new BadRequestException({'error': 'userid must be an integer'});
  }
}

/**
 * Return a [User] as JSON.
 *
 * Throw [NotFoundException] if the 'userid' GET path parameter doesn't exist.
 */
shelf.Response getUser(shelf.Request request) {
  final User user  = db.getUser(_getUserId(request));

  if(user != null) {
    return new shelf.Response.ok(JSON.encode(user), headers: headers);
  } else {
    throw new NotFoundException({'error': 'unknown userid'});
  }
}

/**
 * Set username for the 'userid' GET path parameter [User].
 *
 * The [request] body is expected to adhere to the following format:
 *
 *  {"name":"Some Name"}
 *
 * Throw [BadRequestException] if the body is malformed. Throw [NotFoundException]
 * if the 'userid' [User] doesn't exist.
 */
Future<shelf.Response> setUserName(shelf.Request request) {
  return request.readAsString().then((String content) {
    final int userId = _getUserId(request);
    db.setUserName(userId, _getUserName(content));
    return new shelf.Response.ok(JSON.encode(db.getUser(userId)), headers: headers);
  });
}