Library with optional dependency - node.js

I want to create library that includes some basic code (no dependencies), some react utils and vue utils. And target users likely to use only some part of that.
So first thought I had is to create three separate packages.
But probably it would be more convenient to have only single package. Is there some kind of "provided" (as in Java world) dependency to put all three parts in a single package without having both vue+react as transitive? So if user uses vue instead of react, npm shouldn't download react while installing my library.

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Building monorepo babel-transpiled node JS application with dependencies

I am working on a project that is hosted as a monorepo. For simplification purposes let's say that inside there are three self-explanatory packages: server, a webapp client and library. The directory structure would be something like the following:
the-project
packages
server
src
webapp
src
library
src
All packages employ flow type notation, use a few >ES5 features and, for this reason, go through babel transpilation. The key difference is that transpilation of the webapp package is done via webpack, whereas server employs a gulp task that triggers script transpilation through the gulp-babel package. library is transpiled automatically when web is built.
Now, the problem I have is that for server to build, babel requires library to be built first and its package.json to specify its (built) main JS source file so its transpiled artifacts can be included. As you can imagine, this would quickly become problematic if the project were to contain multiple libraries that are actively being developed (which it does), as all would require building, including any dependent packages (like server in this simple case).
As an attempt to overcome this annoyance, I initially thought of using webpack to build the server, which would take care of including whatever dependencies it requires into a bundle, but I ran into issues as apparently webpack is not meant to be used on node JS applications.
What strategies are available for building a node JS application requiring Babel transpilation, such that the application's source files as well as any dependencies are built transparently and contained in a single output directory?
Annex A
Simplified gulp task for transpilation of scripts, as employed by server.
return gulp
.src([`src/**/*.js`], { allowEmpty: true })
.pipe(babel({ sourceMap: true }))
.pipe(gulp.dest('dist'));
As can be seen above, only server's own source files are included in the task. If src were to be changed to also include library, the task would emit the dependencies' artifacts in server's own output directory and any require('library') statements within would attempt to locate the built artifacts in packages/library and not packages/server/dist, thus resulting in import failures.
First of all, I am not sure what your server is doing. If it is doing a database connection or some calculations then I would not recommend it to be built by webpack. Whereas If your server is just doing Server-Side Rendering and making some API calls to other servers then I would recommend it to be bundled using webpack.
A lot of projects follow this philosophy. For example, you can take a look at something similar, I have done in one of my personal projects [Blubus]. Specifically, you might be interested in webpack-server-config. And also you can take a look at how big projects like spectrum does it.

How to structure your NodeJS application in different modules?

so far i've learned a bit about NodeJS. But now i want to write a huge enterprise app with it and i'm wondering how to setup the structure correctly? Coming from other languages like PHP and Java, i imagine, i would split my project in different NPM modules. For example #mybigproject/customer, #mybigproject/cart and #mybigproject/checkout and so on.
But those submodules would be installed in the node_modules folder of the application skeleton. How would i tell for example Express, that the template files are in the different module directories? Or for example i use TypeORM for data access. So each module would have it's own set of models. How do those models know the database configuration data, as it's only in the main application skeleton, or the other way around, how does the application skeleton should know where to find the models?
Don't use npm modules for different parts of your project.
This components is integral part of your project and usually depend on your global config / schema / routing / etc
Just put it in different files and require it where you need it.
You can get an idea for folders structure from projects like Sail.JS
Use npm modules if you writing some utility that going to serve you for different apps and you want an easy way to upgrade the utility code once for all your apps (or in case you want to share that utility as open source for all of us)
NPM can install your local folder as a dependency. (ref)
npm install <folder>:
Install the package in the directory as a symlink in the current
project. Its dependencies will be installed before it's linked. If
sits inside the root of your project, its dependencies may be
hoisted to the toplevel node_modules as they would for other types of
dependencies.
Your module keeps its original location after installed and a symlink is created as the same name of your module folder in the top level node_modules folder.
In these custom sub-modules, you can use __dirname and relative paths to locate you configuration files to feed to database or other data consumers.
But remember that, sub-modules often serve as utility functions for the main module. They should be independent from the project context.

Module vs. Dependency vs. Library vs. Package vs. Component

I understand that packages hold several modules, but I'm starting to get confused as to if packages and modules are dependencies. Also, libraries to me maybe seem like packages you install via NPM, Nuget, RubyGems, Bower, Homebrew, or Chocolatey. So are libraries packages? Dependencies are something you need to load within your application, to have a certain functionality, but aren't some libraries(jQuery) seen as a dependency? So yea, what are the differences between these concepts?
Libraries are just a bunch of code anyone can use. For example, React.js is a JavaScript library for building front end components.
If I decide to use this library in my app, then React will become one of the modules (aka an installed instance of the library) that my app depends on. So dependencies are pretty much all of the libraries your app depends on, in order to run the way you expect it to run.
I asked the same question you did about dependencies, and I learned that it's a matter of understanding how these terms relate to one another rather than finding isolated definitions for each of them.
Hope this helps!
Basically a package is a pack with some features which fullfills some functionality of your app.
Once you install any package using npm then the package is installed as a dependency in your app inside your package.json file along with its modules(aka libraries consist of classes) stored inside node_modules folder.
I hope its clear now.

Node/NPM: Can one npm package expose more than one file?

I have made a JS library for web development, it consists of several modules, which build up multiple distribution builds. It's fine when it is distributed over cdn or for example using Bower.
But now I'm trying to publish it with NPM so that it can be consumed using Browserify. My question is how can I expose more than one main file statically so that they can be consumable by Browserify.
you don't need to do anything.
require('my-library') // will require the `main` entry point
require('my-library/some-other-file') // will require a different file

Loading backbone.js in a node js app

I'm using node.js and backbone for a web app. Backbone is part of my package requirments. I've used Rails and Backbone before, and the helper gems are nice for piecing together all the assets (js files) that need to get to the client.
With that said, I had to manually download backbone.js and manually add it and all the other supported js libraries in the header of my app's layout file.
Should installing the backbone module get me away from that manual effort to create the required source for my client app? Is there some kind of jammit/asset pipeline?
you should simply npm install backbone in your main directory, this way all the submodules you use will find this exact backbone, and will use it
moreover, this way you can easily extend backbone with additional submodules
I use the stitch package to serve my scripts in node apps. With that, it's as simple as listing backbone.js as a dependency, and I install it with npm. That's convenient.

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