There have been several questions already posted with specific questions about dependency injection, such as when to use it and what frameworks are there for it. However,
What is dependency injection in Angular 8 and when/why should or shouldn't it be used?
Dependency Injection is EVERYTHING in Angular :)
The hierarchical dependency injection system is parallels to the app's component tree and basically, allow us to build the whole applications injecting providers and communicating between components.
The documentation is quite complete and it's worth to study to know the details:
https://angular.io/guide/dependency-injection
Related
I'm learning Vue, and it's ecosystem, and now I read about nuxt.js.
As I understand, this is tool which help us to build Vue apps, but don't we do the same with vite.js?
What's the difference between them?
Vite is a build tool like Webpack, that will basically allow you to work locally on your app and build it for production. It will also bring to the table various loaders, Hot Module Replacement capabilities, environment variables, assets managements etc.
Nuxt is totally unrelated to all of this. It is comparable to Gatsby/Next/Vitepress for a React/Svelte equivalent.
It's goal is to provide more capabilities to VueJS. For example, Vue can only be run as an SPA, meaning that you will not get any kind of indexing with search engines, while Nuxt do have SSR and SSG modes that will allow your websites to be efficiently crawled.
It also brings a lot of Developer Experience niceties: auto import of the composition API, of the components, simple routing, huge ecosystem thanks to all of Nuxt's modules, simpler configuration etc...
It's more like VueJS apps on steroids basically!
Also, latest version of Nuxt (v3) works with Vite out of the box. So, both of them are complementary because you need a build tool to work nowadays in the JS ecosystem + you get more features than just VueJS.
There are tools like vite-plugin-ssr and vitesse (created by one Nuxt's core maintainer btw) who can solve the basic needs of statically generating some routes/etc but it's not as powerful, have smaller communities around it and is overall moving a bit slower.
Trusting people who are behind Nuxt/Vite is also an important aspect, and most of them are well known in the community + are serious daily maintainers!
I have a simple project, and i need implement the Event Symfony 3.4 standalone, however i don't understanding, how to implement it?
Sorry, for my bad english, i'm still learning...
I used php-DI to pass the required dependencies, and I made the abstractions necessary to build the dependencies that Symfony / Events defines.
We are working in an environment where the overall web application is maintained by a core team, but developers internal and external use the frameworks and tool to develop on the application.
If the frameworks used are not backward compatible, overtime it will be impossible to upgrade the systems as other developers used frameworks to develop (old versions for example).
We would like to choose a modern JS framework, thinking a bit more serious about Vue.js.
Can anyone share thoughts about Vue.js roadmap and upgradability of the framework as it goes to V3, V4, etc?
Is the core team's mission to keep it the new versions backward compatible? not to break any APIs offered in the previous versions, etc?
I and my team have been using Vue.js for quite some time for almost 2 years. Before that, we used Angular for 4 years.
I can surely say that future Vue.js will not be fully backward compatible with past Vue. This was true when v2 was released. In fact, this applies to any major JS framework out there. Most of them will not be backward compatible. Look at Angular, Hapi, Koa, Rx.js, etc.
There is a good reason for that. JS is evolving in ways you or me as a single person cannot comprehend in one go. Not all browsers support all features. Web components are coming since 2015 and still a way for them to reach a general consensus. For example, in case of Vue 3.0, the idea is to use ES proxies that will probably be backward incompatible. As web components get adopted by browsers, the idea of Vue.js component will change and it will again be backward incompatible.
Having said this, Vue.js is unlike any other framework out there. The core team is trying its best to preserve core framework compatibility. What happened with Angular 1 -> 2 or Vue 1 -> 2, there is a least likely chance of that happening
As long as you are using Vue public API, you should be good. The transition if any will definitely be smooth, less head-spinning and you will have a clear upgrade (read as - temporarily compatible) path.
Graceful evolution is one of the reasons why we are using Vue as our large-scale application framework.
Our company has a few web applications which in turn depend on a very long chain of internally created and hosted npm packages (we use JFrog Artifactory) each with their own dependencies (and so on). Whenever a bug is fixed or a feature is implemented in a low-level package the current process requires a developer to check in their changes, wait for the CICD build to complete and tests to run, update the parent package, and rinse / repeat all the way up the chain (which can be a very long process).
This can't possibly be a unique situation yet it impacts our productivity greatly and encourages monolithic package development to limit number of packages to update instead of proper code separation.
I can only think of two solutions:
1) Update the web application to use the transitive dependency directly in package.json. This however breaks "encapsulation" because how a direct dependency manages its job shouldn't be known to the web application. If the direct dependency were to use some other transitive dependency later the web application shouldn't be left referencing a now irrelevant package.
2) Modify the web application's package-lock.json to point at the new version of the transitive dependency. This however seems to only work temporarily as merge conflicts or new installs of direct dependencies tend to revert these changes.
I realize that the answer might be to optimize the build / publish process to be less painful and manual but I was hoping others might have encountered a different solution.
FYI - All dependencies are installed with '~' as a version prefix by default.
The correct way to do this (Be in mind that this feature was introduced recently in npm 8.x) is using the overrides section. This new feature introduced allows replacing a package in your dependency tree with another version, or another package entirely.
I've been developing in Aurelia-CLI for about 3 months and like it so far. I think it's a solid framework and obviously escalating in support and usage. That's a good thing!
Before I develop much more of my large app, I'm wondering if I'm using the best build system. I've only tried Aurelia-CLI and am not really familiar with Webpack or JSPM, and therefore I don't know what I'm missing. Are there any clear advantages or disadvantages in using either of the other two build systems, or is using the CLI the most clean and supported approach? Since I'm developing independently, I don't have any external constraints.
Thanks for your help.
UPDATE
This answer is almost two years old. Feel free to research updates and provide another more complete answer and I can replace this answer or point to that answer. Thanks!
Aurelia CLI
Aurelia CLI is great for getting started. It's important to understand that under the covers the CLI is using require.js but proxies the configuration through aurelia.json in your application. This means that you need to understand how to configure aurelia to work with require.js at the moment. Once you need to start configuring to match your workflow or change build steps up it gets a bit cumbersome at the moment. We are working to improve this. There are many features planned for the Aurelia CLI but given at the time of writing this that it is in an alpha / beta state it should generally be used on proof of concept or other smaller apps, not production-ready large scale apps yet.
WebPack
WebPack is arguably the most popular kid on the block at the moment. WebPack is not a module loader, but a bundler. It's important to understand this because while we strive to make Aurelia work great with all module loaders WebPack by default is not in charge of loading modules so a dynamically loaded application requires the developer to expand on this. WebPack is strong in creating optimized bundles and can be easy to use as long as you are comfortable with configure WebPack. WebPack has considerably more GitHub stars due to the popularity from React using WebPack it's hard to say whether the choice is better when using Aurelia simply because of the number of GitHub stars.
JSPM / System.js
Some of the skeletons use JSPM and System.js. The reason is that these are the closest to 'spec compliant' solutions. JSPM tries to help as much as possible when loading from the JSPM registry. If not yet available in the registry you can load from NPM or GitHub directly. From a module loading perspective you use a config.js file that is (usually) automatically maintained when installing dependencies to improve the developer workflow.
Side biased note
On most larger apps at the moment I typically prefer using JSPM / System.js simply because I have a great understanding of the tooling and prefer the control that I am provided. I work on a great number of Aurelia apps that are in production and typically reserve CLI for smaller proof of concept apps and WebPack is a great alternative but I prefer the flexibility and understanding I have with JSPM / System.js at the moment.
The CLI isn't currently feature complete, but it is a much simpler setup. Webpack can basically do anything you want to do, but you'll be maintaining your webpack configuration just as much as you maintain your Aurelia code.
Ok, maybe not just as much, but you'll have to learn Webpack to use webpack. The Aurelia CLI is simple to get started, but has some definite limitations. For example, CSS files that reference external resources won't work w/the Aurelia CLI, but they should work fine with Webpack.
First, I can understand if this post gets shutdown due to its subjective nature.
I believe it's time to re-visit the answers about Aurelia CLI being a second-class tool. I respect both PW Kad and Ashley Grant immensely, but I am just not convinced that a statement like this is true anymore:
There are many features planned for the Aurelia CLI but given at the
time of writing this that it is in an alpha / beta state it should
generally be used on proof of concept or other smaller apps, not
production-ready large scale apps yet.
Notably, I have a production application that way back in the day I started with Aurelia CLI, and changed it to JSPM precisely for the reasons noted. But recently, I rebuilt the same app from scratch using the CLI and I realize that it is much easier to use, particularly managing modules and publishing! And this is an app with Google Maps, Google Analytics, Auth0, DevExpress, Bootstrap, etc.
Just think it is time to give Aurelia CLI a little love. It's ready.
Aurelia CLI is the most preferred option with this announcement.
http://aurelia.io/blog/2017/08/18/aurelia-cli-webpack-update/
Now It has more flexibility for your choice of preferences.