nesting multiple react applications within a single parent application - reactjs

I'm currently working on a project where a situation has come up that I haven't experienced before and not sure I know the best way to handle it. I am looking to have one parent react application that would handle my navigation (with react-router) throughout the different pages of the app and also the login/authentication.
Then in the same repository I would be looking to have multiple other react applications that would render whenever clicked on the from the navigation menu in the parent application, with the navigation menu always remaining on the page.
Does anyone have any good suggestions on how to accomplish this. Maybe even with only one build process (not a necessity, but a nice to have)

I think you are after a micro front end.
You could take a look at https://github.com/CanopyTax/single-spa/tree/master/examples
This is a great project with lots of potential. Unfortunately , I haven't been able to use it since my company insists on using create-react-app and version 2 has been problematical when trying to use the library with it.

Related

Reusable React components and useContext?

I have a (very) small working portfolio site built using React that highlights various simple web development applications. Currently, this entire React app is technically only just one page, but I'd like to eventually expand this site to reflect my additional work as a graphic designer.
I want visitors to be able to choose whether to view my design work or my coding work. I know that this can be done by essentially creating a second copy of each component, but is there any way to basically use the same existing components in my application and just feed "design" versus "web" data through them based on which work visitors are interested in? Could "design" and "web" data would be somehow held in a global state (useContext)? I understand that this description is vague, perhaps intentionally; I just need a push in the right direction for how to keep building out my little site.

How to employ React Thinking

I have taken several react courses that walk through building applications. The courses teach syntax and concepts. But how you solve a problem using react is different!
I am a dinosaur web person who is used to html/javascript.
In terms of a real-world example, such an enterprise level component, how do you tackle it? Do you follow a process where you write pseudo code first? Do you start with writing your code all in one file, and then break them into their own components?
I was going to try to create a modal component (I am sure they exist in a million places already) but for the sake of understanding, but I immediately get hung up in my own confusion.
If you need to use some simple components like modals, buttons etc., you can use one of the popular component libraries like Material UI.

How to use ReactJs in legacy JSF Web application?

We are planning to migrate the UI of an application from XHTML based legacy JSF (1.X) based framework.
We are not going to change everything at once but would, migrate one of the several tabs in ReactJS and keep rest of the pages as it is in XHTML to see how it goes.
I have been trying to find a way to do this but no luck yet. Can anyone give some hint to go ahead with this ?
Thanks in Advance
my Suggestion:
-is to split your pages/tabs using any microfrontend approaches example (iframe, web component )
remove any jsf session dependencies and depend on URL query params (keep only one entry point for your splited app)
apply sso token ,
go ahead with your changes safely without impacting other parts
You would want to prevent coupling between your legacy JSF application and your React components. You could achieve this by making your React-based parts as independent as possible (as with microservices).
Be wary of state managed in application-/session-scoped beans.
Don't depend on stuff that you would rather throw away but can't do at the
moment. Your legacy application is probably too coupled and
monolithic anyway.
Keep in mind that you will (should?) throw away your legacy code eventually.
Keep things clean and fresh for young developers (My experience is, that JSF scares them away - rightly so). This should get yourself a nice and quick developer feedback loop without the need for some heavy build process with legthy container deployments.
Integrate your old and new application using some sort of SSO-like authentication and make your styling seamless.
If you are using Primefaces as a component library, you can also also benefit from their React components, which are not quite on par with the JSF equivalents, but they give you a starting point to get your look-and-feel right. But then again you establish new, somewhat unobvious coupling with your legacy application. Be careful here.

React architecture for a huge business application

So we've recently picked up React in our company as the front-end technology to build our huge business web application. By saying recently, I mean we don't have any previous experience with React (we have a huge background of AngularJS), and by saying huge application, I mean it's really huge and very dynamic with lots and lots of different pieces and functionality.
Because we will have a lot of huge components that all play a very important role and have complex logic inside them, and because we want them to be easily pluggable and reusable, we want them to be as isolated as possible from the outside world and other parts of our application, because otherwise because of their size and complex functionality it would be pretty much impossible to develop and maintain them. That's the reason why we have decided NOT to use Redux, at least in the beginning, while we are developing just the separate components themselves, because it compromises component isolation and makes the whole application data flow logic impossible to understand when there are so many complex components. Although I believe our choice could be wrong, because as I've already mentioned, we have no experience with React.
As I've already mentioned, the application is very dynamic. By that I mean that components are actually rendered by data. We use various configuration provider classes that interacts with our API endpoints to get the pieces of our application's configuration, like configurations of navigation, pages, various forms, lists, etc., and then try to render components that are read from that configuration.
The problem is, after a couple of weeks struggling to get the momentum with React and discover the right patterns and common solutions to our problems, we've been talking in our crew, that maybe React is not the right technology for us, as it's a UI library, not event a framework, and it doesn't help us a lot, but just adds its rendering rules that we have to break at times to achieve the dynamics and component independence we want.
Considering the component isolation and data flow management, I personally have heard that there is a language for front-end development Elm that has pretty robust data flow architecture where each component has its own model that is separate from others, but I don't know whether it's worth a try, as it may fall behind our big requirements pretty soon too.
The reason I'm writing this question here is that I hope to get an insight from people that have a solid background on working with huge front-end applications. I'd like to know whether it's possible to develop such an application with React, whether React is suitable for such complexity and dynamics, whether we really need Redux or something else, what path, practices, ideologies should we follow. If you understood my question correctly, it's more the architecture side that we are struggling with, than the technological. Maybe we are just walking the path that leads to more and more struggle and complexity but not towards production.
There is absolutely no question that React/Redux can (and is widely) used to develop the kind of applications that you describe. Nothing in your description makes what you are building so unique that it excludes React as a platform for building it. We are actively working with a large enterprise customer who is building their entire front end - with 100 + SPA (Single page applications) in React. This is a team of over 100 developers over a 2-3 year project.
The way we structured this has been crucial -
First, you want to choose a UI component library. A few examples below :
MaterialUI - https://github.com/callemall/material-ui
React Strap - https://github.com/reactstrap/reactstrap
React Bootstrap -https://github.com/react-bootstrap/react-bootstrap
Khan Academy React Components https://github.com/Khan/react-components
https://github.com/elementalui/elemental
We basically took one of these and built a component library off of them, because our components are very custom styled.
Second, we created a modular architecture, where each module (SPA) is an npm package with a main container component and redux store.
Finally, we have a central server package, where each of the modules is registered. The server package is responsible for authentication, authorization, logging, routing, etc.
The essence of this answer is not to advise on how to structure a large React application, but to let you know that React can be (and is being) used to develop applications similar to what you are describing.
I'm at the similar situation right now. I have a background in large desktop applications (ERP, LOB - WinForms, WPF) - 1000+ modules, very dynamic (more than 70% of the UI was generated by input data/configuration), adding new functionality was just about extending some configuration (without touching source code).
I'm deeply investigating current web technologies and I'm more and more convinced that React is not a good fit for that. React really shines in small/middle size applications where you (and other team members) develop every page/component 'manually' (not dynamically generated) and you want to have one global state. But it doesn't help you with building large scale application out of the box - it is only UI library (so no support for modules, routing, forms, binding, http requests, static typing (typescript), etc.) and to my surprise, there is no support for style shadowing/encapsulation (you have to integrate, for example, CSS Modules, by your own). And at the end, you have to constantly bother with libraries versioning (to make them always work together is truly time and energy consuming).
I have a great experience with Angular 2/4+ and I think, for now, it is the best technology for that kind of the applications (if you know WPF, it is very similar). It is a full framework, which is prepared to the scaling out of the box. You can split your app into independent modules (specifying which components will be visible to the outside world), every component has public api (statically typed, inputs/outputs) and encapsulated css styles (there is no interference between others).
For the global state (logged in user, global configuration, etc.), you can still use library ngrx/store (which implements Redux pattern and comes with extra nice things, like 'effects' and integrates really well into Angular ecosystem).
I tried to do in Angular really crazy stuff (dynamically generating the whole application from backend configuration) and everything worked perfectly, as expected.
You nailed the issue in your question- react is a view library, not an application framework. The real question is whether React+Redux(or other state management system) is appropriate for a large LOB app.
I will share some insights from our team’s experience in this realm. Large LOB apps have been developed using the MVC/MVP/MVVM design patterns for decades. These are tried and true patterns that ship software. Couple that with dependency injection and you have a modularized, testable, maintainable application. AngularJS (2.0+) is founded on these principles and leverages them deeply. For this reason we use AngularJS for all of our enterprise line of business apps.
React on the other hand is a lightweight, spritely view render that is awesome for smaller applications and client facing pieces (for example taking a dynamic survey or a simple dashboard). We often turn to React and VueJS here because the full AngularJS stack is way overkill and too heavy.
Getting started writing more complex apps in React can really be a struggle, I know exactly how it feels!
As you say, React is a UI lib and not an event framework. That's why you typically need a library to handle events, for example Redux. You clearly state that you decided not to use Redux (you even used capital letters for not :) ). I would take a step back if I were you and reconsider that decision. You say the reason for not using Redux is that your cannot keep your components easily pluggable and reusable when using Redux. I would argue that is not true. Redux is totally decoupled from your React components. Redux only handles receiving events, and managing state. From the React components point of view, it just receives data in props and sends events by calling regular functions. It's possible to still unit-tests, reuse, etc.
I would suggest you take another look at Redux with this in consideration. Happy to help if you have more questions!
React , Redux will make things easier because When it comes to
complex applications you can create Well structured data object. then you can manage the Complete UI through React and its
Materials ... There are some reasons Why this is right choice
State Management ,
Tree Structure data handling,
Reduce the code,
You will be knowing where the changes made (Actions, Reducers)
Your Component will only taking care of UI things
The things that you have to do is Structuring your data
Completely understand your feelings when you start with React and Redux. We were in the same situation when we started with React in our company. At first React has different approach than other frameworks. Yes of course it's not framework, it's just library. You have to start thinking in React way and that is: React components just render state (It's like you render scene on your graphic card at first you have to prepare scene then you are able render), all what component can do is dispatch actions, or better call just action creators.
You need some smart way how to store state in that point I will suggest use Redux.
We also use TypeScript with combination React, Redux. you have to write more code than pure JS but static type control is priceless when you work on large project.
Separating components logic is native approach of react ... you have to separate logic write "Dummy components" and then reuse this with connect. Or passing values as props.
We are using Thunk middleware as action creators it's good because connected component will call just method and logic is in action creators. You have access there to whole state of app then you can fetch something and base on result you can dispatch different actions.
What I like on react/ redux is how to implement async calls etc. First design component to map all states
1) like I have no data
2) data loading
3) loading done
4) loading error
For that you need only one semaphore in you state and a few checks in render method. Then one action creator that will load data and base on progress dispatch action that describing progress.
What is also cool that in react/redux app you have single data flow it's good when new dev jump into project.
For UI we are using Material UI, yes this framework has some problems but nothing what you will not able to deal with.
We are using also Router for navigating in app.
In the beginning I will avoid server side rendering because it will much easier for you start just with client side rendering and with initial state.
When we start for us was useful this template where everything works in one project JavaScriptServices
Then off course great Abramov tutorials.
For design components very useful Storybook
We can write why use or not React for long time ... but What I can say ... for us it was good choice, with some pain in begging but now we have good payback.
We started a large scale business application using Reactjs as frontend technology.
We have over 30 people in the team and we have over 15 modules in our product.
My approach is to the project is developing a common react project that handles only the Authentication, authorization and routing of the application and all other components developed as separate npm react libraries.
To develop the libraries I used https://www.npmjs.com/package/create-react-hook
This library generates the template with an example app which can use to test our library.
Following is the structure of the project
--Library 1 ( Developed using create-react-hook )
--Library 2 ( Developed using create-react-hook )
...
--Library n
--Common Container App (Developed using create react app and have used all above libraries using npm install)
The main advantage of this approach is developers can focus only on their npm packages and they can develop and test relevant component(s) separately.
The deployment also becomes very easy because we can just update npm package of tested version and rebuild the container app and do the deployment without affecting any other part of the application.
We are using this for several months and running the project with a large team without any issue. I think this may be helpful to anyone else too.
So this is just to share my experience working on an enterprise react application that is in production for years in several banks. yes, you heard me right. Now you can imagine how huge the application will be if it's related to fintech (I know it's not always the case). we have huge modules (70+) with a complex logic that pretty much handles a lot of the work that a bank needs. Modules are both isolated and re-useable. I am going to give an example of only one module so you can imagine the size of each module.
Card Production Module
Bulk Card Generation
Bulk Card Export
Bulk Card Request
Card Operations
Card Operations Approvals
Card Printing
New Card Requests
Pin Generation
Pin Printing
This application is a product, not a project and as a product it is configurable. Even the UI is configurable. I have been working on this application as a full-stack developer. Since it's pretty old the state management library that we are using is flux. With state management, the development speed is a little slow but the tradeoffs are better with us not being worried about state management. By far the application has been able to handle huge changes and things which seemed unachievable. Stability has also been a key element throughout this period.
On the back-end, we have Restful services build using Dot Net which supports both MSSQL Server or Oracle depending on the client's needs/feasibility.
After countless react.js projects, I summarized a domain oriented and practical architecture in my blog post.
It is the absolute best practice that I applied many times, enjoy:
http://denislutz.com/domain-architecture-for-react

Deciding on Ionicframework

I have few queries on selecting Ionic framework for our Hybrid app project. Since I have not used Ionic before, few queries may seem idiotic. But i would request all to share their thoughts.
Q1. How easy it is to customize any ionic components as per project requirement in both JavaScript and CSS level?
Q2. How much overhead ionic components create in terms of DOM, Memory usage?
Q3. In case of collection-repeat, say i want to display 10 items out of 1000 items at a time. So at any point in time only say, will there be only 10 divs and will only new data be injected in the previous created divs?
Q4. Say, I have selected Ionic for our project but don't need all the UI or other components in it. So does Ionic gives the flexibility to exclude those components from the framework itself and use the rest?
Q5. How easy it is to include an external library into Ionic if required?
Q6. How easy to debug and Ionic app and the tools available?
Q1. Since Ionic is based on SCSS, it's really easy to customize the visual aspects. I did a video about working with scss and Ionic. As for the javascript side of things, if you know how to work with directives, you should be good.
Q2. Ionic aims to the keep the DOM nice and lean, and not change the DOM like you would with jQuery. As far as memory usage, that really depends on the code you write. You still need to write good code to make sure there aren't memory leaks any where.
Q3. Collection-Repeat doesn't really work that way. Plus when you start dealing with different screen heights, it's not going to be easy to deal with. The best why that we've come up with to deal with that is to just render how ever many it will take to fill the view.
Q4. At the moment no, if you start a project with the CLI, you get the whole bundle. Down the road we're thinking about breaking things into external components, but it's not set up yet.
Q5. It's Angular, so if you have another angular directive that you want to include, the process is really simple. Just include the script tag and inject the module as a dependency. If it's not an angular module, then it's a bit more work to wrap it in a directive, but there are plenty of tutorials out there to help.
Q6. The best thing to remember is that we're dealing with a webview, so you can do a lot of debugging right from chrome on desktop. If you need more debugging once you're on a device, iOS lets you debug right from safari on desktop, and android 4.4+ let's you debug app on a device with chrome.

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