I'm migrating my Node Express JS App to Azure functions. I've more than 250 Routes in my application.
I went through this microsoft link to shift from Node Express JS to Azure functions (solution repo). What I understood is that I'll have to create azure functions for all the routes. i.e. each route will be a function in itself. I've more than 250 routes in my application so, I'll end up creating 250 function.js in their own folder, Is there a less painful way to make this migration.
I thought of doing code level routing based, i.e. grouping all API's by a common purpose and create functions for that top-level purpose and then internally route the request using URI passed to the function. Is there a better way to go about it?
Eventually it might make more sense to create separate functions for benefits like better built-in logging and allow to leverage input/output bindings but would depend on your scenario.
But it is possible to reuse the express app code as is too, and there are two ways you could approach this
A handler function to catch all routes and forward it to express. You could use the azure-function-express npm module which implements this for expressjs. Note that I haven't used this module myself but looks promising
Leverage the Custom Handlers feature. This allows you to run any web server (the expressjs app in your case) and forward requests to the web server. Similarly to 1, you could choose to have just one catch all function since you have a lot of routes to cover.
Note that this feature is currently in preview.
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I am trying to create a general web service using Nextjs.
In my research, I often see cases where Express is used as the backend for Nextjs.
However, Nextjs has an api function.
In what cases do we need to use Express for the backend?
Well, you don't really need Express as the backend server. You should be able to use any framework from any programming language. I guess the reason that you often see it used is because it is the best documented.
Regarding api routes, you will always have to use some kind of backend server as it does not work with next export (aka creating a static folder containing html, css and JavaScript).
Is it possible to combine a Vue.js app with a restful API service?
New to Vue but written my first Vue/Typescript app that is a front end that consumes some public APIs, add extra logic and display results. All works – fine. Now I also want to have my own restful API interface.
I know Vue apps are SPAs, so when I ‘change page’ to myapp.com/page2, it is not fetched from the sever but rather the app just re-renders the display. But is it possible for those routes that are not defined, such as myapp.com/api/whatever, to be a restful interface? That is, consumes requests and return responses? And when hoisted, would a user have access to both a front-end and a back-end, even though the app is running client side?
Did start down this route using express.js but ran into issues as if I was trying to combine chalk and cheese. (Not lease, would need to change the node module to ‘commonJs’).
Would using Nuxt help? Know nothing about Nuxt … yet. Or must I go the traditional way, and write a separate back-end and change my front end to consume it.
I am currently running a web service on an Apache Tomcat servlet container. The web service has a base URL and exposes my applications data using the following structure:
http://[hostname]:[port]/path/to/root/[db_table_name]/[primary_key]?fields=name,...
An HTTP GET call to a URL like the one above would return a JSON formatted string.
Though the documentation for my application describes this as a RESTful API, I am confused because I was under the impression that true RESTful APIs do not use query strings. Rather, as I understand it, a true restful API provides a uniform structure, in the form of resource endpoints.
My questions relate to how I can create a custom API to leverage the existing API using Node.js. I do not want to rewrite the application logic or database calls; I just need to know how I can create the API calls using Node.js (possibly using Express or some other framework) and let the existing API handle the request.
For example, I could write Node.js code using the Express module that has several routes, these routes would handle client requests that in turn would call the existing API (i.e. /path/to/root/[table_name]/[pk]... and return the response.
If my Apache Tomcat server is listening on port 8080, how would I deploy my Node.js server to listen on another port and then redirect requests to the existing WS URL on port 8080.
Does the Express framework support explicitly specifying a root path (such as http://localhost:3000/path/to/root/[table_name]/[pk]) as the default root path?
Finally, I know REST APIs support CRUD operations. In the case of a POST method, does Express (or Node.js) have built-in logic to handle duplicate POST requests so that duplicate records don't get created in the database.
I'm reading through different article and tutorials on REST but I think I'm missing something. Any information or advice that can take me in the right direction would be much appreciated.
there's a lot to cover here but I'll try to cover your three questions. Since you have mentioned using Express I will answer assuming that Express is the framework you are using.
If you are using Express, you can choose which port to listen to when you start the server, so you can choose any port that you like at that point (see here).
If you need to redirect a request you can do so easily with res.redirect() (see here). However, you could also call the other web service directly, retrieve the data and return it to the client instead of redirecting them if you prefer. That would require some more code to make the http requests in node.js though.
I am not 100% sure if this is the answer to your question, but there are ways to add a "base path" or namespace to all of your routes. I found this example where various namespaces are used but in your case you only need one which applies to all routes.
I don't think there is a built-in way to do this. The best I can think of is potentially creating some kind of ID for the request so that if it is sent twice you could use this to check but it's far from ideal.
I would like to add that I'm not sure where the idea that query parameters not being RESTful comes from? I think query parameters are fine because that is how you query! Otherwise you couldn't ask for the right data from your RESTful API. Let's say you have a /posts endpoint and you want to get the posts of a particular user (user ID = 1). The RESTful way to do this would be to issue a GET request to /posts?user=1.
Hope this helps!
I'm looking into node.js which really seem like a pretty nice environment. I've worked with a lot of different Technologies and for server, mainly php and Java (jsp), but dabbled in som RoR and Python.
I find node.js really easy to get up and running and it feels quite natural to work with, and I found some good entry level tutorials.
I just am missing some more intermediate resources. For example when creating bigger frameworks or api's how would you structure or architect it. I set up some smaller api's to try it out where it would go something like this:
I've made use of the Express framework to create a http server, listen to a port, set up an express object and bound some requests.
However these have been quite small, and the purpose has been learning, if I think about scaling up the size of the API for production, perhaps wanting to do other stuff like serve web-pages as well. I find it hard to see how the architecture would look.
It's vague as I am still new to node.js but I'm mainly thinking about things like if you typically keep all api in one file or if there are good ways to split it up into modules? And if anyone know any resource talking a bit more about how to design the architecture when working in node.js
Sorry for the vague question and thanks for reading.
In my opinion, Express is the good way to go if you want to build complex or big APIs.
It is among others easily testable (for instance with Mocha or Jasmine) and customizable, especially thanks to its middlewares.
For the directory structure, what I usually use is (at least) the following:
app.js : the main entrypoint. Will create the express application, indicate which controller to use for every route prefix, and assign the middlewares. Example from a previous project
controllers : will contain the controllers, the functions which will handle the requests, in the same style as in standard MVC frameworks (e.g. UserController, ...). Each controller would create an express Router object and export it. Inside the controllers, individual handlers are in charge of individual API requests, such as /api/users/list. It would use some library to access your data (e.g. Mongoose for MongoDB), and would then send the response to the client. Example (UserController.js)
models : will contain the models with all their attributes and methods. In my case, it would be the Mongoose models. Example (Song.js)
middlewares : will contain the various middlewares of the project. A practical example would be a middleware checking for an access token in the incoming request, and returning a 403 HTTP error if not. Example (AuthMiddleware.js)
helpers : various helpers
tests : unit tests of you API
This could be the minimal directory organization. On top of that, you may want to use a templating engine such as EJS to serve webpage. Take a look at « Use EJS to template your node application ».
This is only to give you an overview of what an express directory structure could look like, but there are of course plenty (better?) other possibilities. Hope that gives you a quick and useful insight :)
I understand that Express resides on the server and Angular resides on the client but, as far as I know, Angular can do everything that Express can do which is
routing
interacting with the database
It kind of seems like maybe Express is needed in order for an AngularJS app to be served by Node.js but I'm not sure.
So what are the benefits to adding Express to an AngularJS app?
There are things which should be done server side (i.e. Express, not Angular), most notably user input validation - Angular, as it's client side, can be tampered.
Also, if you'll ever want to offer access type other than web app (i.e. mobile app), you'll probably need an API anyway - Express can do this, Angular don't.
Finally, database access - usually Angular app will need to connect to some kind of backend to perform CRUD operations. You'll either go with hosted DB like Firebase, or you'll end up using your own database. Latter scenario is more popular and you'll need Express (or similar) for that.
Express and AngularJS do not mutually exclude one another, they serve different purpose - in fact it's perfectly fine to use both - express for all your serverside logic, and Angular for client side logic.
Express can be used to host the APIs for AngularJS's service/factory to consume. You can consider AngularJS as MVC and the API on Express as SOA.
There is lot of stuff that one wants to control from server. And that is the place where the server side frameworks come into picture.
An web app is not just some html pages linked together. There are lot of other things that needs to be implemented
Model validation.
Keeping model consistent. Remember multiple users can access the same model at any give time and even change it.
Controlling resource access.
Triggering workflows.
Business Logic.
and other such thing require a server framework. So as mentioned earlier the client side frameworks like AngularJS complement server side frameworks.