I have an .html file and a corresponding .js file (using Bootstrap) I need to deploy this to Heroku.
I'm really trying to avoid having to rework this entire project, I need more than just bootstrap styling. This project pulls data through an API, and populates based on the data pulled. Input is also needed from user to update the backend through API...
I've tried to find examples of how to accomplish just pulling in html/js into nodeJS/expressJS... but it seems most examples are just to use Bootstrap.css for styling, or there's no actual UI interaction coded in the example.
Any links or input will be greatly appreciated.
If you want to render a html file prepared in the server side. You need a view engine like ejs or pug. You can pass data into the html page. Another way of doing the same thing is a framework called NextJs or NuxtJs but you need to know React or Vue.
You can add bootstrap.css into the public folder and express.static will handle the problem. Or you can use CDN links too.
Then you can add the url of bootstrap.css into the html head.
https://expressjs.com/en/guide/using-template-engines.html
https://expressjs.com/en/starter/static-files.html
I've been working on the front-end so far, now I'm going to create my first full-stack application. I want to use node.js, express and AWS for this.
At the design stage, I already encountered a few problems. Therefore, I have a few questions and I am asking you for help:
Can I send a message (simple JSON or database value) from the server to all clients who have already opened my home page in a simple and cheap way?
I'm not talking about logged in users, but all who downloaded the main page (GET, '/')?
Using the admin panel ('www.xxxxxxxxx/admin'), I want to send a message to the server once a day. Then I want to change the HTML to display this message. I was thinking to use EJS for this and download this message from the database.
Can I make it better? If someone visits my home page (GET, '/'), EJS will download the message from the database each time! Even though its value is the same for 24 hours. Can I get the value once and then use it until the value is changed? How to store the message? As a JSON on the server? Or maybe in the .env file?
If the user refreshes the page, do I have to pay for calling all AWS functions to build the page each time? Even if nothing has changed in the files?
How to check if the page has new content and then send it to the user, instead of sending the unchanged page files: .html, .js, .css, etc.?
Can I send the user only the changed, dynamically created html file, and not send again unchanged .js and .css files?
Does every user who opens the home page (GET, '/') create a new connection to the server using WebSocket / socket.io?
I will try to answer some of your questions:
Can I send a message (simple JSON or database value) from the server to all clients who have already opened my home page in a simple
and cheap way? I'm not talking about logged in users, but all who
downloaded the main page (GET, '/')?
I guess you mean sending push notifications from the server to the user. This can be done with different services depending on what are you trying to build.
If you are planning to use GraphQL, you already have GraphQL subscriptions out of the box. If you are using AWS, go for Appsync, which is the AWS service for GraphQL.
If you are using REST and a WebApp (not a mobile app), go for AWS IoT using lambdas. Here is a good resource using Serverless Framework (API Gateway + lambdas + IoT) for unauthenticated users: https://www.serverless.com/blog/serverless-notifications-on-aws
If you are planning to use notifications on a mobile app, you can go for SNS, the "de facto" service for push notifications in AWS world.
Using the admin panel ('www.xxxxxxxxx/admin'), I want to send a message to the server once a day. Then I want to change the HTML to display this message. I was thinking to use EJS for this and download this message from the database. Can I make it better? If someone visits my home page (GET, '/'), EJS will download the message from the database each time! Even though its value is the same for 24 hours. Can I get the value once and then use it until the value is changed? How to store the message? As a JSON on the server? Or maybe in the .env file?
Yes, this is the way it's expected to work. The HTML is changed dynamically using frontend code in Javascript; which makes calls (using axios for example) to the backend every time you get into, i.e. "/" path. You can store this data in frontend variables, or even use state management in the frontend using REDUX, VUEX, etc. Remember the frontend code will always run in the browser of your users, not on your servers!
If the user refreshes the page, do I have to pay for calling all AWS functions to build the page each time? Even if nothing has changed in the files?
What you can do is store all your HTML, CSS, Javascript in an S3 bucket and serve from there (this is super cheap, even free till a certain limit). If you want to use Server Side Rendering (SSR), then yes, you'll need to serve your users every time they make a GET request for example. If you use lambda, the first million request per month are free. If you have an EC2 instance to serve your content, then a t2.micro is also free. If you need more than that, you'll need to pay.
How to check if the page has new content and then send it to the user, instead of sending the unchanged page files: .html, .js, .css, etc.?
I think you need to understand how JS (or frameworks like React, Vue or Angular) do this. Basically you download the js code on the client, and the js makes all the functionality to update backend and frontend accordingly. In order to connect frontend with backend, use Axios for example.
Can I send the user only the changed, dynamically created html file, and not send again unchanged .js and .css files?
See answer above. Use frameworks like React or Vue, will help you a lot.
Does every user who opens the home page (GET, '/') create a new connection to the server using WebSocket / socket.io?
Depends on what you code. But by default what happens is the user will make a new GET request everytime he accesses your domain, and that's it. (It's not establishing any connection if you don't tell the code to do so).
Hope this helps!! Happy coding!
On my website I have some categories in the database which don't change often. I am using the NextJS framework. In order to decrease the load time and make category control load faster I am thinking of putting categories in a json file under /static/data/categories.json and let React fetch that json file instead of making a database call. I have read about multiple approaches to importing static json files including json-loader. However, I am thinking of making an api call something like the following from React once on the home page and store the contents in redux state so that I could use them wherever I need. My intention here is whenever categories are modified, I update categories.json and the client will fetch the updated json file. Deployment downtime is not an issue for me.
const categories = yield call(request, `${BASE_URL}/static/data/categories.json`, options);
My questions are:
Is this a right approach to load a json file from the server keeping in mind I would want to update the file every few months without the need to redeploy the whole website.
Can a json file become a bottleneck if thousands of concurrent users try to access it. I am using express with nginx. Would using express.static help at all?
Thanks in advance.
I developed a small node.js app in which I can configure conditions for a custom javascript file, which can be embedded in a webpage, and which modifies the DOM of that page in the browser on load. The configuration values are stored in MongoDB. (For sake of argument: add class "A" to DOM element with ID "B" )
I have difficulties to figure out the best way to serve requests / the JavaScript file.
Option 1 and my current implementation is:
I save a configuration in the node app and a distinct JavaScript
file is created for that configuration.
The page references that file which is hosted and served by the server.
Option 2 and where I think I want and should go is:
I saves a configuration (mongodb) NO JavaScript file is created Pages
a generic JavaScript link (for instance: api.service.com/javascript.js)
Node.js / Express app processes the request, and
returns a custom JavaScript (file?) with the correct values as saved in mongodb for that configuration
Now, while I believe this is the right way to go about it, I am unsure HOW to go about it. Any ideas and advise are very welcome!
Ps: For instance I wonder how best to authenticate or identify the origin, user and requested configuration. Shall I do this like: api.service.com/javascript.js&id="userID" - is that good practice?
Why not serve up a generic Javascript file which can take a customized json object (directly from mongodb) and apply the necessary actions? You can include the json data on the page if you really need to have everything embedded, but breaking up configuration and code is the most maintainable approach.
I am building a MEAN application (Angular + node + Express + Mongo).
In this app there are users who can upload a limited amount of pictures (lets say 5).
I really want to avoird storing too many data on my server.
So I am looking for a module that let users upload the images to a service such as picasa, imageshack... The service should be transparent to the user.
When it's done, I save the picture URL in my DB and so I can retrieve it and display pictures easily.
Do you know such module / tutorial to do that? Does it even exists?
I have been looking but it seems to not exists.
The easiest way to have a file upload service with AngularJS as the front end and NodeJS as the backend is to use the jQuery File Upload for use with AngularJS, which can be found here.
It makes use of a directive that you can use to upload your file.
You need to specify a route to which the uploaded file should be POST'ed to.
In this route handle, that is in you Node.js server, you can then post it to the external image hosting servers. This is something that you can write on your own or you can use the node.js modules for the respective hosts (if they exist).
I find a service doing it:
http://cloudinary.com/
With a nodejs integration:
http://cloudinary.com/documentation/node_integration
It seems perfect (free up to 500 MO and 50.000 pictures, far enough for my needs).