Develop Reference

Is there anyway i can update a firestore document automatically even if app is closed, is there a listeener or something

i have a firestore and project that needs to be updated automatically without user interaction but i do not know how to go about it, any help would be appreciated. take a look at the json to understand better
const party = {
id: 'bgvrfhbhgnhs',
isPrivate: 'true',
isStarted: false,
created_At: '2021-12-26T05:20:29.000Z',
start_date: '2021-12-26T02:00:56.000Z'
}
I want to update the isStarted field to true once the current time is equal to start_date

I think you will need Firebase Cloud Function, although I don't understand exactly what you mean.
With Cloud Functions, you can automatically run (add, delete, update, everything) codes on Google's Servers without the need for application and user interaction.
For example, in accordance with your example, it can automatically set "isStarted" to true when it hits the "start_date" time. If you want to code a system that does not require user interaction and should work automatically, you should definitely use Cloud Functions. Otherwise, you cannot do this on the application side.
For more info visit Cloud Functions

Ok, I managed to find a workaround to updating my documents automatically without user interaction since the google billing service won’t accept my card to enable cloud functions for my project, I tried what I could to make my code work and I don’t know if other peeps would follow my idea or if my idea would solve similar issues.
What I did was that in my nextjs file I created an API endpoint to fetch and update documents after installing the firebase admin SDK, so I fetched all documents and converted all start_date fields in each document to time and checked for documents whose start date is less than or equal to current date, so after getting the document, I ran a firestore function to Update the document.
Tho this will only run when you make a request to my domain.com/api/update-parties and never run again
In other to make it run at scheduled intervals, I signed up for a free tier account at https://www.easycron.com and added my API endpoint to EASYCRON to make requests to my endpoint at a minute interval, so when the request hits my endpoint, it runs my code like other serverless functions😜. Easy peezy.

Embeddable js interpreter for user's code?

Imagine website, where user can generate content via js.
For example.
User clicks button
It requests our api (not user's api)
Api returns object with specific fields.
We show select with user's defined options generated by user's code or some calculated result based on data we sent.
The idea is to give user an ability to edit visible content (using our structures, we know beforehand which fields in returned object do what things).
First solution "developed" in 5 minutes.
Users clicks button
It send all required data as context to our api.
We fetch from database user's defined code
// here is the code which we write (not user) and we know this code is safe
const APP_CONTEXT = parseInput(); // this can be parameters from command line
const ourLibrary = require('ourLibrary');
// APP_CONTEXT is variable which contains data from frontend. We control data inside APP_CONTEXT, user can not write to it
// here is user defined code
const someVar = APP_CONTEXT['fieldDescribedInOurDocumentation'];
const anotherVar = APP_CONTEXT['anotherFieldFromDocumentation'];
ourLibrary.sendToFrontend(someVar + anotherVar);
In this very simple example once user clicked on button, we sent api request to our api, user's code has been executed, we show result of execution. ourLibrary abstract the way the handling is completed.
The main problem as I think is the security. I think about using restricted nodejs process. No network access, no file system access.
Is it possible to deny any import/require in nodejs process? I want to let user only call all builtin js function (Math.min, Math.max, new Date(), +, -), declare functions and so on. So it will work like a sophisticated calculator. And also we should have an ability to send it back to frontend. For example, via rabbitmq + nodejs + websockets. We can use simple console.log if former is the problem.
Some possible solution (not secure, of course) using nodejs interpreter. We execute interpreter every time when action is required.
const APP_CONTEXT = parseInput();
const ourLibrary = require('ourLibrary');
const usersCode = getUsersCode();
eval(usersCode);
Inside usersCode they use ourLibrary.sendToFrontend to produce the result. But this solution allows user to use any builtin nodejs functions, like const fs = require('fs'). Of course access will be restricted using linux system (selinux or similar) but can I configure/setup nodejs to run as simple js interpreter? May be there is some other js interpreter exists which is safe to use? Safe means: only arithmetic, Date function, Math functions and so on. No filesystem access, no network access.

How to make per user base logging with hapi js

I am using winston logging framework and logging on basis of log level, but now i am facing difficulties in tracking down bugs. So we decided to make logging on per user basis, and this is where i ran into problem.
What i want to acheive?
log file for every user will be generated on every hour. (We can skip every hour constraint in this thread) and every user has unique identifier 'uid'.
What i have?
I have followed architecture as used here 'https://github.com/agendor/sample-hapi-rest-api'. Some additional lib modules exist too.
Currently i am using winston library (but i can afford to replace this if needed).
Brief introduction of flow
Currently, i have access to request object in handler function only, but i want to log events in DAO, library functions too ( on per user basis). 'Uid' is available to me in handler function in request object as i put uid in request in authentication middleware.
My solution (which is not elegant)
pass request object ( or only uid) to every function and log (using winston) event. Custom transport will determine where (in which file, on basis of uid) to put the log.
Certainly, this is not elegant way as every function must have uid parameter in order to log event, which seems bad.
What i want from you?
A better, elegant approach which is scalable too.
Related post: https://github.com/hapijs/discuss/issues/51

Try taking a look at Continuation-Local Storage:
https://github.com/othiym23/node-continuation-local-storage
Heres a good article on implementing it within express:
https://datahero.com/blog/2014/05/22/node-js-preserving-data-across-async-callbacks/

Adding a user to PFRelation using Parse Cloud Code

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

Publish data from browser app without writing my own server

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.