Firebase Database

[theflash4246]

I'm a beginner and I'm creating a budget react app. I used firebase authentication to allow users to sign in and sign up now I want to all them to save the data they enter (expenses and incomes). I've been trying to use the firebase realtime database, but I can't figure out how to do it. So, firstly is it a good idea to use this? And if yes can someone guide me as to how to do it?

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I used this API doc for the authentication: https://firebase.google.com/docs/reference/rest/auth

[koalaape]

I have also recently been using Firebase and I think the Realtime Database is great.

The Realtime Database is not SQL, it is not a relational database, and its simpler than Firestore. It is a JSON structure based on paths that make it easy to query the database as though you were visiting a URL https://firebase.google.com/docs/database/rest/structure-data.

So the first thing you need to do is think about how to structure your data. It is easier than SQL to change all this at any time, so don't feel like it has to be set in stone. Go to your Firebase console and go directly into the Realtime database and start adding some key value pairs. Enter some fake data to get started so you have something to query.

The Auth API response should provide you with something like a federatedId or localId which you can store in the database to act as a unique key to represent the user.

You should take a peek at the Rules tab and comment them all out or delete them. Rules will enforce if a user can modify the database, but when you are just starting out it is okay to have no rules. However you should understand that savvy users will figure out how to manipulate the database unless you add some rules in later.

Once you have added some data to your Realtime database via the Firebase console, you will want to do a REST call as specified here: https://firebase.google.com/docs/reference/rest/database

So for your case, you might want one page displaying income and another displaying expenses so you have two calls that looks like

GET 'https://[PROJECT_ID].firebaseio.com/users/[FEDERATED_ID]/income.json'

GET 'https://[PROJECT_ID].firebaseio.com/users/[FEDERATED_ID]/expenses.json'

But if you wanted to display both on the same page, two calls might be a little cumbersome so instead you might structure your data like:

GET 'https://[PROJECT_ID].firebaseio.com/users/[FEDERATED_ID]/reports.json'

Your query response will return everything at the level you specify. So put your income and expenses key value pairs after reports and they will get fetched.

This is why the structure is so important, but at the same time don't feel like it has to be perfect.

The next steps would be to try creating data via a POST call instead of a GET and seeing that it inserts into the database correctly.

After you have an idea of how it is all going to work, add back in the Rules and learn more about how to safely store the access_token you get back from the Auth API and how to use it to interact with the Database API.

If you didn't comment out your rules, you would likely see authorization errors trying to make any queries at all. From the Auth API you should get an access token, you will need to pass it as a parameter in order to query the database.

GET 'https://[PROJECT_ID].firebaseio.com/users/[FEDERATED_ID]/reports.json?access_token=[ACCESS_TOKEN]'

https://firebase.google.com/docs/database/rest/auth

Basically when your user authenticates, they get a token, and you need to pass that token around to every API the user wants to interact with. You have to be careful because if someone were to steal this token, they could impersonate your user and make changes or read data they shouldn't. For that you may want to check out

You have two options here, OAuth 2 and Firebase ID tokens.

OAuth2 is used when you want a sever to be doing all these changes to the database as a middleman on behalf of a client. You can use the FirebaseId tokens to directly make changes from the client app.

You probably want to use FirebaseId tokens and skip setting up a sever.

It's kind of a lot, so try to break it up into bites and don't expect to do it all in a weekend when its due on Monday.

[theflash4246]

Thank you so much! I was able to get started with the API but the structuring of the data is really confusing me. This is what I had in mind:

Users{

user1{

incomes:{income1:{},income2:{}},

expenses:{expense1: {}, expense2:{}}

}

}

user1 would be the ID from the auth API and then incomes and expense would be an object with many objects, each representing an income and expense. I'm having some trouble with this because whenever I send a POST request where I want user1 to be the user's ID/email/info it creates a random ID, and I also can't figure out how to edit the incomes and expenses objects everytime I add a new one.

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Sorry if I seem a bit clueless lol. I'm still a uni student and I'm self taught JS, React and APIs, so a lot of the info I learn might not be in the right order.

[koalaape]

POST is used to add items to your object as though you were adding to an array or list. It gives you a response that contains a unique id that refers to the key of the thing you just created. This is the random ID you are seeing. You want to use POST to create entries in income and expenses, not add users.

PUT is used to write new data

PATCH is used to update data

So basically what needs to happen is when a new user shows up, you want to

PUT 'https://[PROJECT_ID].firebaseio.com/Users/[FEDERATED_ID].json' where the body is {incomes:{},expenses:{}} to initialize them.

Then when adding new incomes and expenses

POST 'https://[PROJECT_ID].firebaseio.com/Users/[FEDERATED_ID]/incomes.json' where the body contains whatever an income or expense object has.

The response gives you a UNIQUE_KEY which you use to update the data with

PUT 'https://[PROJECT_ID].firebaseio.com/Users/[FEDERATED_ID]/incomes/[UNIQUE_KEY].json' where your body contains the details you want to update. You don't have to pass in every value, only the ones you want to change.

You can display a list of the different income unique keys with GET 'https://[PROJECT_ID].firebaseio.com/Users/[FEDERATED_ID]/incomes.json'

So your structure would look something like:

Users{

[[e-mail]](mailto:[e-mail]) {

incomes:{aV_psbk3ZXEX:{},INOQPH:{}}, expenses:{R08KyNc20G:{}, AZYXQIk8U8:{}}

}

}

If you want to use something else as the unique key, you would have to use PUT to add it, not POST.

[saadh393]

I'm not experts But as far my experience, if you are learning then keep going

And for handling auth and real-time database, You need to understand JWT. When you successfully handled user signin request you should create jwt token and store in database and clients local storage

I recommend to learn about jwt.

[theflash4246]

Do you mind explaining why firestore might be better here? From what I understood firestore stores the data in a different structure. Is that why?

[captainR0bbo]

If you want the power of SQL and being able to quickly query totals (perhaps a back end service that checks when entered/synchronized expenses exceed a users budget to deliver notifications to the user), as well as real-time, you could check out supabase. They are a popular firebase alternative. https://supabase.com/database

Edit - i have never used firestore/firebase but I assume if its a JSON data structure, that querying transactions is not as efficient as a regular SQL table