I want to make an app where people can text (sms) their name to sign a petition and then their name would be added to a list of signees on a website for the petition.
The sms messages would be handled by Twilio and then be processed by a Node.js app. I would like to use Angular on the front end.
Question: What would be the best way to store the names? Do I need something like MongoDB or would a database be overkill? I'd also like to verify that only one name per phone number is entered.
If you don't use a database you'll need to store it in memory. This will mean when you restart the server or it reboots you will lose your names.
So the short answer is yes you will need a database.
As for checking if there are duplicates there are many method with mongodb.
You can use a find query first to check that it does not exist already.
You could use upsert which will replace a previous one matching one.
However you can use any type of database that you wish.
I'd like to vote in favor of a relational database, probably it's a good fit for your kind of project.
Take in account that you can also store some interesting fields that comes with the Twilio request like country and state to list some.
You can take a look at this tutorial where not only you can get the SMS but reply to the user to have a smooth user experience in the process: https://www.twilio.com/docs/sms/tutorials/how-to-receive-and-reply-node-js
Related
I am trying to build a web app where users can receive notifications if their posts get likes. This functionality is actually working but the notification component renders only when the page reloads. But I want it to re-render the notification component as soon as there is a change that occurs with it. I am trying to make this work with SocketIO both in client and server but it feels like there should be a way easier way to solve this issue. How?
One way to achieve this is to use server-sent events (SSE), which can be seen as a uni-directional
and simplified version of WebSocket (only server can send data to clients). You might need route param or query string so that users can connect to different channels.
If it doesn't have to be so real-time (i.e. receiving notifications 1 minute after somebody liked the post is okay), you could also try (long)polling.
However, since post-like table may contain a huge amount of data, constantly querying it is expected to result in bad performance on the server. Also, adding an extra column to mark if the user has been notified about a specific like is trivial.
A possible workaround might be to create a new table, say pending-like-notification, which is used to stored all pending like notifications. Whenever a post is liked, we insert a new record into this table.
Therefore, when a user tries to query if any of his posts is liked recently, in the backend we lookup this table instead of the post-like table, and delete the selected rows after the user has been notified so that the amount of data in this table can stay low (hopefully).
All in all, in this scenario, I think SSE and WebSocket will be better choices.
I have a realtime app where users are clicking on a button at the exact same time. It is a rideshare app where a ride will show up on all the users's screens, and then 2 users will basically simultaneously push the "accept ride" button. This creates problems because it saves the first user onto the ride via a database save call, but then the second user oversaves the first user. Once a user accepts the ride, another user should not be able to accept the ride. It creates major problems because the first user should just "accept the ride" while, with the second driver, it should just tell them "another driver is accepting the ride". The problem is that I can not even run a query to check if the ride already has a driver because this is all happening so quickly. The first user will hit "accept ride", then it will save them to the ride. The second user will hit "accept ride", and it will check if the ride already has a driver. It doesn't yet because the first save is still finishing. Then the second user is oversaved on the ride. It just is happening way to simultaneously where queries don't really solve the problem.
Sorry if this is a confusing explanation. I have never had to deal with this realtime of a problem, so I am not sure where to start. I think I need to build some queue or something that only lets this happen once at a time. Any direction of what to even google would be helpful. Thank you! My backend is written in node.js and I use MongoDB on Heroku.
You need an atomic check and set operation in your database so in one atomic database operation, you can verify that it's not already accepted and, if not, accept it. That will only allow one person to accept it, any others will fail because it's already accepted and the API can feed that back to the user interface. The key word here is "atomic" and how you achieve it depends upon the specific database. For MongoDB, see Mongo any way to do atomic check and set.
Here's another reference: Help writing an atomic update in mongodb.
These solutions use mongodb's findandmodify so presumably, you would attempt to find a document with this id and that is also not accepted and if found, you would modify it to be accepted. Then, since the findandmodify is atomic, nobody else can get in between your find and your modify so when their findandmodify gets a turn, they won't find a document that is both the right id and is not accepted because someone else accepted it before they got in.
So i have been struggling with this one question some time now:
How to handle details Page or deep linking on the Frontend.
So, say, we got a paged collection endpoint with user entities in it and a React App consuming the endpoint.
The flow would be, user authenticates, gets collections, clicks on an item and is either:
Redirected to a new Url say: webapp.com/users/userid
A modal opens with the user details.
Say we got a scenario were two people working with the webapp, Person 1 wants to share a link with Person 2. Person 2 should do some updates on a specific user, which is identified by the link.
The link should be something like : https://www.webapp.com/users/{slug or id}
With Option 2 this functionality is not mappable.
With Option 1 we got to expose the ids in the response to identify the resource, which may work, but we would still need to hardcode the url, as the findById method is not exported as a Uri Template.
So, my Solution would be to add a slug for the resources, implement a search method by the slug, and then get the user, if found, by its self-link.
Sounds like a good solution for me, but on the other hand, I would have to add an extra frontend id(the slug here) which would need to be also unique, to the database model.
So how do you guys handle a problem like this, or is there anybody using spring data rest in this way or in production mode where you have the handle situations like this?
Should mention that this isn’t a primary problem with spring data rest but rather with hateoas itself.
thanks in advance
Florian
You don't need to hardcode URL template. Spring data rest will generate links for each resource.
You can refer to it from front end by some format like: {your_user_object}._links.self.href
English is not my native language and i don't understand difference between query and request.
What is the difference between words and how to use them correctly on the web
Request means ask for something and it shall be given. You need that thing.
Query means ask whether or not something is true/ available or false/not available, you may not get that thing back but you'll get the status, state or info.
Request means ask to collect that object.
Query means ask to confirm the state of an object ex. Availability, true/false,
Can I have some food to eat? You are requesting for food.
Is that way good? This is a Query:
A request is like when I ask you to go to the supermarket. Here, I’m requesting you to leave your current place, go to the supermarket to bring one or many items and come back. Now, you can go to the supermarket but once you arrive you will ask yourself, what should I bring? In order to make your visit to the supermarket successful, I should give you a list of things that you need to bring or do at the supermarket, give you a description for the items and tell you in which aisle or department you can find them. This list now is representing your query.
So, if your client needs to fetch some data for example from a remote server, you will need to make a request. This request has a type, like ‘GET’ to fetch resources or data back, or ‘POST’ to do an operation like creating a new user account.
For the request to do its job, you have to specify what data or resources you need this request to fetch and where to find it. It’s like what items do you need to buy from the supermarket and from which aisle can you find them. For example, your request can have a query to return a specific user’s data based on his id. But you need to know to whom should you send the request with this query in order to get the user’s data back based on the passed id.
In order to make a request, you need to send it to your backend’s application that you can access using an IP or a domain mapped to it. Something like: “http://www.mywebsite.com”. But to fetch specific type of data, like the user’s data you need to tell your backend application what are you searching for. This is specified by something called the “path”. For example: “http://www.mywebsite.com/users”. The path here is the “/users” part. The query works when you submit to this domain with the path one or more query parameters, like the user’s id. So, you will make a GET request to “http://www.mywebsite.com/users/1234”, where “1234” here is representing the user’s id that you need to fetch its data. It’s like telling you to go to the supermarket named “mywebsite.com”, go to the “users” isle or department and grab the item with the id “1234”.
I hope that I managed to simplify the concepts a little bit for you.
Mohammed's answer above is great and very detailed. In summary:
First of all, query and request can both be nouns and verbs. E.g:
I requested a refund.
We received a request for a refund.
I queried the price.
We received a query about the price.
To request something is to ask for something, an object or a favour etc. A request is a polite demand. To query is to ask about something i.e. you are wanting information. A query is a question.
Also, QUERY is an inquiry(Query and inquiry are synonyms)
They are both requests but the difference is that the QUERY is a precise request. In informatics, if you need information about something you need to send a specific request with precise information.
"I queried information about user account Maxim Pavlov" = "I need to know about this website users. In particular, I need to know if there is any Maxim Pavlov registered on this site".
If you are Arabic, best translations in Arabic would be, request = طلب and query = إستعلام)
I thought about this question and I think the Ahmed's answer is misleading to say the least.
When web developers talk about request, they usually mean request done via HTTP. There are other protocols, but HTTP is certainly the most common. Request tend to be fourfold: get, post, put and delete. A request is almost always associated with an endpoint. A request is more than just ask for something. For instance, a put request is basically either add information or a file stored on a web server or update it. On the other hand, a query, in the language of a web developer, typically means some information he would like to extract from the database where a certain condition needs to be met.
I will give you an example. When building an API, you may have just two endpoints which are mapping to a post request and a get request. When you hit the endpoint associated with the get request, by design it will always return the "current time" which requires no query in a database. Meanwhile, when you hit the endpoint associated with the post request, by design it will always get the leap years between, say, 1900 and 2000 which are all stored in the database and requires a database query to fetch that information back to you.
The Abdullatif's answer is by and large correct though.
The native application doesn't show all the activity, only the most recent.
Therefore I lose 70-90% of my notifications overnight. There must be a way to get all that historical data.
I told you can't, but, thinking.. you can. :)
The API don't provide that facility.. You can check all endpoints here: http://instagram.com/developer/endpoints/
But you can iterate over all your medias an get all comments and likes. If you store it locally, after, will be possible to request API again and check your new unseen interactions.
It will work for likes and comments.