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I have a problematic here:
I'm builing a mobile app with ionic frmaework who needs to be able to work offline.
I'd like to adopt the CouchDB / PouchDB solution. But to do that i need to know how to put my data in the noSQl datatbase (MySQL user before ...). So, nosql is new to me but it seems interesting.
So my app has a connection part so a user database. And each user has documents who are attached to him. But many users can have many documents (sharing documents). And I want to replicate the data of one user (so his information + his documents on the mobile app).
What I thought is this:
One database per. One database for all Document with a server filtering to send only the documents that belongs to the user.
And on the client side I'd juste have to call :
var localDB = new PouchDB("myuser");
var remoteDB = new PouchDB("http://128.199.48.178:5984/myuser");
localDB.sync(remoteDB, {
live: true
});
And like that on the client side I'd have something like that :
{
username: "myuser",
birthday : "Date",
documents : [{
"_id": "2",
"szObject": "My Document",
},
{
"_id": "85",
"szObject": "My Document",
}]
}
Do you think something like that is possible using Couchdb and pouchdb, and if yes, am I thinking about it the right way?
I read it's not a problem to have one database per document, but I don't know if the replication will work like I imagine it
Plain CouchDB doesn't have any per-document access options, but these could be your solutions:
A. Create a View, then sync Pouch-To-Couch with a filter. But although this will only sync the documents that the user is supposed to see, anyone with enough knowledge could alter the code and view someone else's documents or just do anything with the database actually (probably not what you're looking for).
B. Create a master DB with all documents, then a database for each user, and a filtered replication between the master & per-user-dbs. Probably the simplest and most proper way to handle this.
C. Unfortunately there isn't a validate_doc_read (as there is a validate_doc_update) but perhaps you could make a simple HTTP proxy, which would parse out incoming JSON, check if a particular user can view it and if not, throw a 403 Forbidden. Well you'd also have to catch any views that query with include_docs=true.
(late reply, I hope it's still useful - or if not, that you found a good solution for your problem)
I'm trying to automate a Meteor app available online (namely, Meteor.com's account management - to add a collaborator to all 170+ organizations I'm a member of).
I've researched reverse engineering Meteor apps but haven't been able to figure out correctly from DDP messages what methods are available on the server.
Meteor methods can be seen among the WebSocket frames by looking for "msg":"method". For example, if you log into https://meteor.com, go to Organizations, and add a username to an organization in your Meteor account, you can see this in the WebSocket frame:
{
"msg":"method",
"method":"addOrganizationMember",
"params":["jspdf", "splendido"],
"id": "2"
}
(If the output looks uglier than that, vote for the Chrome team to implement this feature request for prettifying WebSocket frame dumps.) That method name, however, failed when running Meteor.call('addOrganizationMember', 'jspdf', 'splendido') in the console, with an error that the method wasn't found (404).
So you just want to check if the method exists first & then if it does, make the call?
I think you'd want something like:
if (Meteor.server.method_handlers.addOrganizationMember) {
Meteor.call('addOrganizationMember', 'jspdf', 'splendido')
})
For client methods, it'd be Meteor.connection._methodHandlers
Hopefully I understood, set me straight if I didn't.
I am using Parse.com with my iPhone app.
I ran into a problem earlier where I was trying to add the currently logged in user to another user's PFRelation key/column called "friendsRelation" which is basically the friends list.
The only problem, is that you are not allowed to save changes to any other users besides the one that is currently logged in.
I then learned, that there is a workaround you can use, using the "master key" with Parse Cloud Code.
I ended up adding the code here to my Parse Cloud Code: https://stackoverflow.com/a/18651564/3344977
This works great and I can successfully test this and add an NSString to a string column/key in the Parse database.
However, I do not know how to modify the Parse Cloud Code to let me add a user to another user's PFRelation column/key.
I have been trying everything for the past 2 hours with the above Parse Cloud Code I linked to and could not get anything to work, and then I realized that my problem is with the actual cloud code, not with how I'm trying to use it in xcode, because like I said I can get it to successfully add an NSString object for testing purposes.
My problem is that I do not know javascript and don't understand the syntax, so I don't know how to change the Cloud Code which is written in javascript.
I need to edit the Parse Cloud Code that I linked to above, which I will also paste below at the end of this question, so that I can add the currently logged in PFUser object to another user's PFRelation key/column.
The code that I would use to do this in objective-c would be:
[friendsRelation addObject:user];
So I am pretty sure it is the same as just adding an object to an array, but like I said I don't know how to modify the Parse Cloud Code because it's in javascript.
Here is the Parse Cloud Code:
Parse.Cloud.define('editUser', function(request, response) {
var userId = request.params.userId,
newColText = request.params.newColText;
var User = Parse.Object.extend('_User'),
user = new User({ objectId: userId });
user.set('new_col', newColText);
Parse.Cloud.useMasterKey();
user.save().then(function(user) {
response.success(user);
}, function(error) {
response.error(error)
});
});
And then here is how I would use it in xcode using objective-c:
[PFCloud callFunction:#"editUser" withParameters:#{
#"userId": #"someuseridhere",
#"newColText": #"new text!"
}];
Now it just needs to be modified for adding the current PFUser to another user's PFRelation column/key, which I am pretty sure is technically just adding an object to an array.
This should be fairly simple for someone familiar with javascript, so I really appreciate the help.
Thank you.
I would recommend that you rethink your data model, and extract the followings out of the user table. When you plan a data model, especially for a NoSQL database, you should think about your queries first and plan your structure around that. This is especially true for mobile applications, as server connections are costly and often introduces latency issues if your app performs lots of connections.
Storing followings in the user class makes it easy to find who a person is following. But how would you solve the task of finding all users who follow YOU? You would have to check all users if you are in their followings relation. That would not be an efficient query, and it does not scale well.
When planning a social application, you should build for scalabilty. I don't know what kind of social app you are building, but imagine if the app went ballistic and became a rapidly growing success. If you didn't build for scalability, it would quickly fall apart, and you stood the chance of losing everything because the app suddenly became sluggish and therefore unusable (people have almost zero tolerance for waiting on mobile apps).
Forget all previous prioities about consistency and normalization, and design for scalability.
For storing followings and followers, use a separate "table" (Parse class) for each of those two. For each user, store an array of all usernames (or their objectId) they follow. Do the same for followers. This means that when YOU choose to follow someone, TWO tables need to be updated: you add the other user's username to the array of who you follow (in the followings table), and you also add YOUR username to the array of the other user's followers table.
Using this method, getting a list of followers and followings is extremely fast.
Have a look at this example implementation of Twitter for the Cassandra NoSQL database:
https://github.com/twissandra/twissandra
the past few weeks I've been hard at work with Angular, Node, TDD, Heroku, Amazon S3 etc. Trying to get a better picture of how a fully scalable SPA with a solid backend is built, working with grunt, bower, haven't dipped my toes in TDD using Jasmine yet, though I understand how the tests are being made through Karma, this is supposedly my next step.
One thing is sure: IT IS A LOT OF INFORMATION
On to the Questions/Rationale on working with all these technologies.
First things first, I played with
Angular App https://github.com/angular-app/angular-app
NG Boilerplate https://github.com/joshdmiller/ng-boilerplate
and read many dozens of posts etc.
I found NG Boilerplate to be most logical structured (as far as my understanding of these things go).
As a demo project (which evolved from something really small) I want to make a Single Page CRUD Application using:
NodeJS as backend
Express as a web app framework
NG Boilerplate as the Client
The app deployed to Heroku
MongoDB for DB
Amazon S3 for dynamic storage
Now I want to use Angular-Apps's (https://github.com/angular-app/angular-app) server as a backend to my NGBoilerplate kickstarter
I want to know how:
from what I see the client connects directly to MongoDB?
how does the angular client communicate back and forth to express ?
I read an interesting article http://www.espeo.pl/2012/02/26/authentication-in-angularjs-application related to how the authentication works.
Long Story Short, without me asking a ton of questions, could someone please describe in detail the workflow of such an app? Getting the session, login, access to editing the content, tying express routes to angular routes (e.g. X route can be accessed by the admin only) etc. ##
there'a big blur in my head :).
In the last months I played a lot with these issues and questions and I got to the following conclusion:
For my purposes, I needed an app that relies almost entirely on Angular, without a separate backend, and the present backend should be from Angular.
Why? Because I want all of my eggs in one basket, I don’t want to configure a ton of stuff on a lot of different parts.
As a basis for my project I ended up using ng-boilerplate, as a boilerplate :), with some changes to the development process, Grunt tasks etc, this is for everybody to figure out, depending on each particular project.
Well, the main issue I’m gonna touch here is that, for a true backend, made in Angular, we need secure routes and a secure persistence method, a database.
For the app, I took advantage of the ng-boilerplate's modular and dependency aware structure, I think it’s perfect for a Angular app.
Anyhow, I’m gonna take things top to bottom (final product wise, the build env as I said above, it’s up to you, but ng-boilerplate is awesome), here we go.
On the upper layer we have the actual Angular app, made just the way we want
The server container, is a NodeJS server with express and other modules to take PARTIAL care of the routing on different browsers and devices (In my app, I made HTML5 routing that is augmented by express, .htaccess like settings whenever there’s a partial URL it should redirect to index where Angular will read the path requested and zapp you to that location)
For my case, the whole things runs on Heroku, on a Node.JS application, you can install several other things there if you want to.
Now, for the persistency, to have authentication and security, and NOT to rely on backend for that, I am using firebase (https://www.firebase.com/), there’s some great tutorials there to help you going and have true persistence in your Angular APP, with routes when you are logged in, access to custom tables/objects in DB when you are logged in etc. It’s the real deal.
If you don’t want to rely OAuth’s possible sites to log in with (Facebook, github, persona or twitter) and want custom emails and addresses you can do that directly with Firebase, to create accounts and delete them etc.
FIREBASE Angular Backend.
So, Firebase, just like they say on the site is a powerful API to store and sync data in realtime.
I don’t know exactly how to approach this, so I’m gonna start it with creating a Firebase database. Once we create it, in the backend we have several options, one of which is security.
{
"rules": {
".read": true,
".write": "auth != null"
}
}
Here, if we read the documentation on https://www.firebase.com/docs/security/security-rules.html we’ll learn that we can add rules for each ‘table' in our database, so we can have like 3 protected ’table’ objects and some that are not protected.
We can protect tables per user basis, per different rules, if logged in or not, we also have inheritance for rules etc, pleas read the documentation there, it really is a good read.
Now, for these rules to take effect we need to enable the Firebase Simple Login and select the desired login method, from Facebook, Twitter, Github, Persona, Email&Password and Anonymous.
For a real app, we need to write info to DB also as anonymous (user sessions etc) and also as logged (with either of the options above) to store and read information.
Me, I wanted to go the quick easy way and made a Facebook authentication, reading the docs there I made a quick Facebook app, and in the settings of the application on Facebook I’m putting Firebase’s backend https://www.dropbox.com/s/xcd4b8tty1nlbm5/Screenshot%202014-01-22%2013.51.26.png
This gives a interim link to login to Facebook and have access to ’tables’ that are otherwise locked if the rule is auth !=null.
NOW, onto the Angular backend.
Firebase provides a library for us to put in our app, and a SimpleLogin lib, also, for Angular, a factory service called AngularFire.
In my case, I made local firebaseService with use methods that connects to my DB:
angular.module('firebaseService', ['firebase'])
.service('firebaseService', function ($firebase, $rootScope) {
//Input data in Firebase
var URL = "https://glowing-fire-xxxx.firebaseio.com";
var tellFirebase = function(ID, JSON) {
users = $firebase(new Firebase(URL + '/' + ID));
users.details = JSON;
users.$save('details');
};
return {
addUser: function(ID, JSON) {
tellFirebase(ID, JSON);
if ($rootScope.debugStatus === true) {
console.log('Firebase Service .addUSer Called');
}
},
getUser: function(ID) {
if ($rootScope.debugStatus === true) {
console.log('Firebase Service .getUser Called');
}
}
};
})
From here we do our READ/WRITE, on the controller’s page I have this:
It’s worth noticing that I have a middleware service (storageManagement) where I switch between Firebase and MongoDB, to avoid confusion.
.controller( 'SomeCtrl', function SomeController( $scope, storageManagement, $firebase, $firebaseSimpleLogin ) {
/*===========================
* ==== FIREBASE LOGIN
* ===========================*/
var URL = "https://glowing-fire-XXXXX.firebaseio.com";
var users = new Firebase(URL);
$scope.auth = $firebaseSimpleLogin(users, function(error, user){});
if ($scope.auth.user == null) {
//$scope.auth.$login('facebook');
}
console.log($scope.auth);
//$scope.auth.$logout('facebook');
$scope.doLogin = function() {
console.log($scope.facebookemail);
console.log($scope.facebookpassword);
$scope.auth.$login('facebook');
$scope.$on("$firebaseSimpleLogin:login", function(evt, user) {
storageManagement.runFirebase();
});
/* example of logging in while asking access to permissions like email, user_list, friends_list etc.
* auth.$login('facebook', {
rememberMe: true,
scope: 'email,user_likes'
});*/
};
$scope.doLogout = function() {
$scope.auth.$logout();
};
});
I’m adding the $firebase service to my controller, and the $firebaseSimpleLogin one.
This here exposes to scope two buttons, login/logout, that popup the OAuth window from Facebook, with email/password setting you won't need to to go through this I think, for a full understanding please read the full docs at firebase.
SO, once we are logged, we can access tables described in the rules, if we choose email/password, actually even for Facebook or other methods, we can assign certain rules for certain IDENTITIES, so you could have a ADMIN table where you could save settings that get READ on page load to apply whatever you want.
Now, with routes, we can check for the $scope.auth status, if WE PUT IT IN $rootScope, and check for the status when going to a route, if the status checks, we get to that route and it gets populated with stuff from the DB, otherwise, even if someone hacks it’s way to that route it won’t see anything because there are no permissions to read that table for unauthorized/wrong email users.
This is loosely based on this article, http://www.ng-newsletter.com/posts/back-end-with-firebase.html … I had a hard time changing the mindset from what the guy wrote there, but, after ONE WHOLE day, of reading the docs (and setting up middleware, mind you) from Firebase I figured it out, and it works.
The connection to the DB is exposed like one BIG object where you can do whatever operations you want.
This isn't the most complete explanation, but it should get you well on your way to making some awesome things:D
The best example of this that I've come across is called angular-app.
It's very comprehensive and addresses all your needs. It's written by one of the authors of the fantastic book "Mastering Web Application Development with AngularJS".
https://github.com/angular-app/angular-app
From the github repo:
AngularJS CRUD application demo
Purpose
The idea is to demonstrate how to write a typical, non-trivial CRUD application using AngularJS. To showcase AngularJS in its most advantageous environment we've set out to write a simplified project management tool supporting teams using the SCRUM methodology. The sample application tries to show best practices when it comes to: folders structure, using modules, testing, communicating with a REST back-end, organizing navigation, addressing security concerns (authentication / authorization).
We've learned a lot while using and supporting AngularJS on the mailing list and would like to share our experience.
Stack
Persistence store: MongoDB hosted on MongoLab
Backend: Node.js
Awesome AngularJS on the client
CSS based on Twitter's bootstrap
Build
It is a complete project with a build system focused on AngularJS apps and tightly integrated with other tools commonly used in the AngularJS community:
powered by Grunt.js
test written using Jasmine syntax
test are executed by Karma Test Runner (integrated with the Grunt.js build)
build supporting JS, CSS and AngularJS templates minification
Twitter's bootstrap with LESS templates processing integrated into the build
Travis-CI integration
I need users to be able to post data from a single page browser application (SPA) to me, but I can't put server-side code on the host.
Is there a web service that I can use for this? I looked at Amazon SQS (simple queue service) but I can't call their REST APIs from within the browser due to cross origin policy.
I favour ease of development over robustness right now, so even just receiving an email would be fine. I'm not sure that the site is even going to catch on. If it does, then I'll develop a server-side component and move hosts.
Not only there are Web Services, but nowadays there are robust systems that provide a way to server-side some logic on your applications. They are called BaaS or Backend as a Service providers, usually to provide some backbone to your front end applications.
Although they have multiple uses, I'm going to list the most common in my opinion:
For mobile applications - Instead of having to learn an API for each device you code to, you can use an standard platform to store logic and data for your application.
For prototyping - If you want to create a slick application, but you don't want to code all the backend logic for the data -less dealing with all the operations and system administration that represents-, through a BaaS provider you only need good Front End skills to code the simplest CRUD applications you can imagine. Some BaaS even allow you to bind some Reduce algorithms to calls your perform to their API.
For web applications - When PaaS (Platform as a Service) came to town to ease the job for Backend End developers in order to avoid the hassle of System Administration and Operations, it was just logic that the same was going to happen to the Backend. There are many clones that showcase the real power of this strategy.
All of this is amazing, but I have yet to mention any of them. I'm going to list the ones that I know the most and have actually used in projects. There are probably many, but as far as I know, this one have satisfied most of my news, whether it's any of the previously ones mentioned.
Parse.com
Parse's most outstanding features target mobile devices; however, nowadays Parse contains an incredible amount of API's that allows you to use it as full feature backend service for Javascript, Android and even Windows 8 applications (Windows 8 SDK was introduced a few months ago this year).
How does a Parse code looks in Javascript?
Parse works through classes and objects (ain't that beautiful?), so you first create a specific class (can be done through Javascript, REST or even the Data Browser manager) and then you add objects to specific classes.
First, add up Parse as a script tag in javascript:
<script type="text/javascript" src="http://www.parsecdn.com/js/parse-1.1.15.min.js"></script>
Then, through a given Application ID and a Javascript Key, initialize Parse.
Parse.initialize("APPLICATION_ID", "JAVASCRIPT_KEY");
From there, it's all object manipulation
var Person = Parse.Object.extend("Person"); //Person is a class *cof* uppercase *cof*
var personObject = new Person();
personObject.save({name: "John"}, {
success: function(object) {
console.log("The object with the data "+ JSON.stringify(object) + " was saved successfully.");
},
error: function(model, error) {
console.log("There was an error! The following model and error object were provided by the Server");
console.log(model);
console.log(error);
}
});
What about authentication and security?
Parse has a User based authentication system, which pretty much allows you to store a base of users that can manipulate the data. If map the data with User information, you can ensure that only a given user can manipulate specific data. Plus, in the settings of your Parse application, you can specify that no clients are allowed to create classes, to ensure innecesary calls are performed.
Did you REALLY used in a web application?
Yes, it was my tool of choice for a medium fidelity prototype.
Firebase.com
Firebase's main feature is the ability to provide Real Time to your application without all the hassle. You don't need a MeteorJS server in order to bring Push Notifications to your software. If you know Javascript, you are half way through to bring Real Time magic to your users.
How does a Firebase looks in Javascript?
Firebase works in a REST fashion, and I think they do an amazing job structuring the Glory of REST. As a good example, look at the following Resource structure in Firebase:
https://SampleChat.firebaseIO-demo.com/users/fred/name/first
You don't need to be a rocket scientist to know that you are retrieve the first name of the user "Fred", giving there's at least one -usually there should be a UUID instead of a name, but hey, it's an example, give me a break-.
In order to start using Firebase, as with Parse, add up their CDN Javascript
<script type='text/javascript' src='https://cdn.firebase.com/v0/firebase.js'></script>
Now, create a reference object that will allow you to consume the Firebase API
var myRootRef = new Firebase('https://myprojectname.firebaseIO-demo.com/');
From there, you can create a bunch of neat applications.
var USERS_LOCATION = 'https://SampleChat.firebaseIO-demo.com/users';
var userId = "Fred"; // Username
var usersRef = new Firebase(USERS_LOCATION);
usersRef.child(userId).once('value', function(snapshot) {
var exists = (snapshot.val() !== null);
if (exists) {
console.log("Username "+userId+" is part of our database");
} else {
console.log("We have no register of the username "+userId);
}
});
What about authentication and security?
You are in luck! Firebase released their Security API about two weeks ago! I have yet to explore it, but I'm sure it fills most of the gaps that allowed random people to use your reference to their own purpose.
Did you REALLY used in a web application?
Eeehm... ok, no. I used it in a Chrome Extension! It's still in process but it's going to be a Real Time chat inside a Chrome Extension. Ain't that cool? Fine. I find it cool. Anyway, you can browse more awesome examples for Firebase in their examples page.
What's the magic of these services? If you read your Dependency Injection and Mock Object Testing, at some point you can completely replace all of those services for your own through a REST Web Service provider.
Since these services were created to be used inside any application, they are CORS ready. As stated before, I have successfully used both of them from multiple domains without any issue (I'm even trying to use Firebase in a Chrome Extension, and I'm sure I will succeed soon).
Both Parse and Firebase have Data Browser managers, which means that you can see the data you are manipulating through a simple web browser. As a final disclaimer, I have no relationship with any of those services other than the face that James Taplin (Firebase Co-founder) was amazing enough to lend me some Beta access to Firebase.
You actually CAN use SQS from the browser, even without CORS, as long as you only need the browser to send messages, not receive them. Warning: this is a kludge that would make my CS professors cry.
When you perform a GET request via javascript, the browser will always perform the request, however, you'll only get access to the response if it was from the same origin (protocol, host, port). This is your ticket to ride, since messages can be posted to an SQS queue with just a GET, and who really cares about the response anyways?
Assuming you're using jquery, your queue is https://sqs.us-east-1.amazonaws.com/71717171/myqueue, and allows anyone to post a message, the following will post a message with the body "HITHERE" to the queue:
$.ajax({
url: 'https://sqs.us-east-1.amazonaws.com/71717171/myqueue' +
'?Action=SendMessage' +
'&Version=2012-11-05' +
'&MessageBody=HITHERE'
})
The'll be an error in the console saying that the request failed, but the message will show up in the queue anyways.
Have you considered JSONP? That is one way of calling cross-domain scripts from javascript without running into the same origin policy. You're going to have to set up some script somewhere to send you the data, though. Javascript just isn't up to the task.
Depending in what kind of data you want to send, and what you're going to do with it, one way of solving it would be to post the data to a Google Spreadsheet using Ajax. It's a bit tricky to accomplish though.Here is another stackoverflow question about it.
If presentation isn't that important you can just have an embedded Google Spreadsheet Form.
What about mailto:youremail#goeshere.com ? ihihi
Meantime, you can turn on some free hostings like Altervista or Heroku or somenthing else like them .. so you can connect to their server , if i remember these free services allows servers p2p, so you can create a sort of personal web services and push ajax requests as well, obviously their servers are slow for free accounts, but i think it's enought if you do not have so much users traffic, else you should turn on some better VPS or Hosting or Cloud solution.
Maybe CouchDB can provide what you're after. IrisCouch provides free CouchDB instances. Lock it down so that users can't view documents and have a sensible validation function and you've got yourself an easy RESTful place to stick your data in.