redstone_mapper_mongo is a MongoDB extension for redstone_mapper.
This package is a wrapper for the mongo_dart driver.
Create a MongoDbManager
to manage connections with the database:
var dbManager = new MongoDbManager("mongodb://localhost/dbname", poolSize: 3);
If you are using redstone_mapper as a Redstone.dart plugin, you can pass a MongoDbManager
to getMapperPlugin()
,
so a database connection will be available for every request:
import 'package:redstone/redstone.dart' as app;
import 'package:redstone_mapper/plugin.dart';
import 'package:redstone_mapper_mongo/manager.dart';
main() {
var dbManager = new MongoDbManager("mongodb://localhost/dbname", poolSize: 3);
app.addPlugin(getMapperPlugin(dbManager));
app.setupConsoleLog();
app.start();
}
//redstone_mapper will create a "dbConn" attribute
//for every request.
@app.Route("/services/users/list")
listUsers(@app.Attr() MongoDb dbConn) =>
dbConn.collection("users").find().toList();
//If you prefer, you can also create a getter to access the
//database connection of the current request, so
//you don't need to add an extra parameter for every route.
MongoDb get mongoDb => app.request.attributes.dbConn;
The MongoDb
object is a wrapper that provides helper functions for encoding and decoding objects:
import 'dart:async';
import 'package:redstone/redstone.dart' as app;
import 'package:redstone_mapper/mapper.dart';
import 'package:redstone_mapper/plugin.dart';
import 'package:redstone_mapper_mongo/manager.dart';
import 'package:redstone_mapper_mongo/metadata.dart';
class User {
//@Id is a special annotation to handle the "_id" document field,
//it instructs redstone_mapper to convert ObjectId values to String,
//and vice versa.
@Id()
String id;
@Field()
String username;
@Field()
String password;
}
MongoDb get mongoDb => app.request.attributes.dbConn;
@app.Route("/services/users/list")
@Encode()
Future<List<User>> listUsers() =>
//query documents from the "users" collection, and decode
//the result to List<User>.
mongoDb.find("users", User);
@app.Route("/services/users/add", methods: const[app.POST])
Future addUser(@Decode() User user) =>
//encode user, and insert it in the "users" collection.
mongoDb.insert("users", user);
However, the MongoDb
class doesn’t hide the mongo_dart
API. You can access a DbCollection
with the
MongoDb.collection()
method.
Also, you can access the original connection object with the MongoDb.innerConn
property.
Moreover, you can use a MongoDbService
to handle operations that concerns the same document type:
MongoDbService<User> userService = new MongoDbService<User>("users");
@app.Route("/services/users/list")
@Encode()
Future<List<User>> listUsers() => userService.find();
@app.Route("/services/users/add", methods: const[app.POST])
Future addUser(@Decode() User user) => userService.insert(user);
It’s also possible to inherit from MongoDbService
:
@app.Group("/services/users")
class UserService extends MongoDbService<User> {
UserService() : super("users");
@app.Route("/list")
@Encode()
Future<List<User>> list() => find();
@app.Route("/add")
Future add(@Decode() User user) => insert(user);
}
MongoDbService
will by default use the database connection associated with the current request. If you are not using
Redstone.dart, be sure to use the MongoDbService.fromConnection()
constructor to create a new service.