How does WebPack Serve Pages/Chunks in Code Splitting? - reactjs

How does WebPack serve different chunks when your user is on your website?
Because we have one GET request to server at the beginning - which would serve all of our main.js.
So then we go to a different page... We're not doing another GET request, but the server is able to serve this information?

Related

Getting data but POST, PUT, DELTE request not working on netlify

My frontend is deployed on Netlify. all the get request working well but POST, PULL, DELETE request is not working.
My backend is on Heroku..
Is it CORS problem or else?
Thank you very much.
this is my console after post request
From your linked screenshot, it appears that you're connecting to your API using relative URLs, for example: /api/something. Locally, this would most likely work as you'd most likely have your backend running too.
However, on production this would not work, because browsers will resolve /api/something relative to the domain which is now on Netlify. Since Netlify doesn't have your backend app running, and there is no asset at /api/something, Netlify sends back a 404.
The solution would be to use Netlify Rewrites: https://docs.netlify.com/routing/redirects/rewrites-proxies/. You could add something like:
/api/* https://your-heroku-url.com/:splat 200!
... in a file named _redirects which should be added to the publish folder on Netlify.
This would resolve /api/something to https://your-heroku-url.com/something. You might have to change the redirects based on your configuration.

How to redirect HTTP to HTTPS with Sails/React?

Current state: Depending on the npm start script, my web app is accessible by at the http:// address, or the https:// address, but not both.
Goal: I'd like the app to run on https://, and for any http:// requests to be redirected to https://.
App info: The web app is created with Sails for the server, and create-react-app for the UI. To run locally, I use two terminals to start each up (server on :1337, UI on :3000). To run in prod, I build the UI and copy the build into the server folder, then start the server on :84 (:80 already taken).
What I've tried:
I've tried adding redirection on the Sails server by adding middleware and policies.
I've tried adding redirection on the UI by adding a script in the HTML header, checking for window.location.protocol in index.js, adding to the http-proxy-middleware, and using react-https-redirect.
In all cases, I'm able to access the app if I go to the https:// address, but get err_empty_response from the http:// one. None of my http:// requests seem to even reach the app or server.
I've heard that using NGINX as a load-balancer may solve this, but I'm hoping for a solution that doesn't require as much set up. Any suggestions?

Managing routes in reactjs app in production

How is routing handled in a built react app?
Specifically, in a development environment, we can simply hit <host>:<port>/<some-path> and the corresponding component is loaded, but once the app is built, we get a bunch of static files and single index.html file, which are then served by some server.
Now, upon hitting the url <server-host>:<server-port>, the app works as intended, but upon entering the path, say <server-host>:<server-port>/<component-path>, a 404 error is returned.
If there is, say a button, upon clicking which, the same /<component-path> is to be redirected, the app works, but then again upon refreshing that page, 404 error occurs.
How can this be solved? What is the correct way to serve such apps having many components at different routes?
approach1:(recommended)
In server config you should point all urls ( http://ipaddress:port/<* any url pattern>) to index.html of react-app . this is known as fallback-mechanism.
And when any request comes,index.html of React app will take care of that automatically because it is single page application.
approach2:
Use HashRouter in React app. So You will not have to configure anything.
Depending on which server you are deploying to, you should redirect all errors to the index.html look for the configuration maybe htaccess or for example if it an AWS S3 bucket you just specify the error page to the same index.html file that is served. Then you handle actual error in your code using a routing library like maybe react-router-dom to take care of actual error. Your failure is because in normal circumstances in a static host when you provide a URL like <server-port>/<component-path> the assumption the server makes is that there is a folder with name component-path in your root directory which has an index file from where to load and display but in the case of React single page application, everything is managed by the index.html. So every request has to pass via the index.html

Build React app with express backend for domain http://example.com

I have a web application in React that I needed to implement a contact form. The application is created using create-react-app and the server folder added. For the form I used sendgrid mail. Does the server work on port 4567, how do the app build to work on the domain? It is a one-page application.
Thx, it is important.
When running in production, a React app is simple HTML, CSS, and JavaScript. These files are sent from your server to a client when requested in the same way that requests/responses are handled for any web page. There are a few steps that need to be done before your React app is ready for production
1: Create a Production Build
First you need to create a production build of your app. This process takes all of your separate .js or .jsx files and puts them together into a single minified file, and the same for .css. Then your index.html is updated to include a link to the CSS and script to the JS. This is done so that only three files will need to be sent rather than the 10s or 100s that exist in development.
If you used create-react-app to start your application, you can use the command:
npm run build
to do this. Otherwise, you need to have webpack installed, and then run:
node_modules/.bin/webpack --config webpack.prod.js --mode production
(which you might want to add as a script to package.json).
See React: Optimizing Performance for more.
2. Serve your Application
Now your server should have a route for your application and when it receives a request on that route, the server should respond by sending index.html from your client/build/ directory (where client/ is the directory of the React app).
Here is an example with Node/Express as the server (in app.js):
const path = require('path');
app.get('*', (req, res) => {
res.sendFile(path.join(__dirname), 'client', 'build', 'index.html');
});
Note that this is just the way to send a static file using Node and can easily be done with any server.
Additional
You mentioned you want to submit forms with your application. If your routes for receiving POST requests match the routes that the forms are on (e.g. form is on /form and server listens for POST on /form) you can just use the default HTML form submission. However this is not a great way to do things when using React because then routing will be controlled by your server rather than by React. Instead you should use some sort of AJAX method to submit the form.
Since your server is now serving your React app (rather than React serving itself as in development), you can just make relative requests and those requests will be made to your server. For example the request (using the fetch API):
const models = await fetch('/api/models');
Will be made to your_host/api/models by default.
in the package.json add
"proxy": "http://localhost:4567"

react + webpack - pass POST data to build

Coming from a PHP background, I used to have an index.php which does two things:
serve the webpage if no parameters were set;
or serve JSON data when a specific POST parameter was included in the request.
Something like this:
// -- index.php
<?php
if ($_POST["some_parameter"]) {
...
echo json_encode(someArrayData);
exit(0);
}
?>
<html>
...
</html>
I have built the complete frontend application with npm, webpack, webpack-dev-server, and react. Having completed the first part, how can I effectively serve JSON data instead of HTML when a request includes a specific POST parameter?
I can see 2 ways of doing this:
Build the frontend as usual and everytime I build the bundle, modify index.html, inject my PHP code in it, and rename it to index.php. I then would have to run this folder via apache or nginx, so I'd be able to run the index.php script. This method is downright ugly and is probably the worst way to do it.
Run a separate PHP server which just serves data or redirects to the static webpack-generated build. All requests should then start from this server, and this server determines whether to serve data or redirect to the frontend. The problem comes to neatly passing the POST data received from the request to the static react app. As far as I know, the only way to do this would be to include a URL (GET) parameter to the redirect and manually parse it with javascript on the frontend. This is a dirty solution, in my opinion.
So, to summarize:
I need an efficient way to get POST data in a react/webpack/webpack-dev-server environment.
It should work with my hot-module-replacement dev setup.
I'm fine with switching to a node-based backend like express.
There shouldn't be any ajax involved in the static react app.
Any ideas? There has to be a way to do this properly.
UPDATE: I solved this by simply copying an index.php from my source directory to my build directory via the webpack config. I serve the build folder to a PHP server and keep a webpack --watch building my source.
I lose built-in features like auto-reload and css injection, but it's worth the convenience of not having to implement SSR for a very simple task (getting a single POST variable).
For anyone interested, I also added 2 npm scripts:
npm run start runs my original webpack-dev-server with hot-reload, serving static content including a static index.html file
npm run static runs the webpack --watch which copies the index.php file to the build directory
This lets me have hot-reloading when developing frontend, and allows POST data fetching when programming logic.
It's easy, convenient, and works on most web hosting providers.

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