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I wrote a package with babel-jest to transform specified js files. I installed this package in my working project and tried to run unit test under the project. There's a .babelrc file in my project, so babel-jest would use the babel configuration file automatically, which is not what i want.
Note: babel-jest is automatically installed when installing Jest and will automatically transform files if a babel configuration exists in your project. To avoid this behavior, you can explicitly reset the transform configuration option:
// package.json
{
"jest": {
"transform": {}
}
}
I tried to reset jest transform in package.json file of the project, according to the description in jest docs. But it seemed not working, babel-jest still used the babel configuration file of the project.
Is there any way to avoid using .babelrc in project while running jest?
Related
Is it possible to build a TS source into a single file, which would also contain node_modules imported packages' source?
That would be very helpful in a serverless project. I have done this before on a non-TS project but was using webpack (for another reason).
It seems this was briefly possible before but was due a bug https://github.com/Microsoft/TypeScript/issues/13414 ?
You will need to use a bundler such as webpack to bundle your compiled code and all your node_modules dependencies. The TypeScript compiler (tsc) just transforms TypeScript code into JavaScript, and won't deal with bundling.
I am used to using NPM packages with Webpack, but I'm wondering how you're supposed to use NPM packages without Webpack.
I know how to install packages. I just don't know how to use them, since you can't just import modules in plain js.
Webpack compiles a bunch of javascript files and combines them into a single one for web distribution. NPM downloads javascript files through packages.
Here's some scenarios where you might use NPM without webpack
You are doing Node.js server-side javascript development. There's no webpack here
You are using a webpack alternative like rollup or browserify
You directly do anything else with the files npm downloads. Maybe you concatenate, throw them in a Makefile or maybe you expose node_modules directly to the world and reference their full paths directly.
Most of my web and server-side development is without webpack.
Why you can't import in plain js?
If you correctly define the package entry point like
"main": "dist/index.js",
"module": "dist/index.js",
Those files can be plain ES6 javascript with named exports or export default, and you can import them after intalling your package with regular import.
You don't need webpack nor babel to make an mpm module. Just put in any folder the files you want to distribute, specifying the main entry point and export elements on that file.
Now... in an angular or react application for example, they may install your component and will use babel and webpack to first transpile your component to ES5 with babel, and then bundle your code together with the rest of their app using webpack.
For front-end, not node.js but still NPM modules.
HTML can import directly ES6 modules but the file must be in .mjs format and provide export default, Module.exports in regular .js file wont't work. This is not a common thing and you'll run into problems if there are subdependencies that don't use ES6 modules. If you find a module that supports it. i.e. some-module
npm install some-module
And in the same directory next to node_modules create index.html pointing straight to the modular bundle
<h1>I'm HTML</h1>
<script type="module">
import SomeModule from './node_modules/some-module/bundle.mjs';
const mod = new SomeModule();
mod.doStuff();
</script>
Here's an article about this https://medium.com/passpill-project/files-with-mjs-extension-for-javascript-modules-ced195d7c84a
npm init
To create a package.json file
npm install --save <package>
To install a package and save it in the package.json file
OP EDIT: If anyone else comes across this: the app was created using create-react-app, which limits importing to within the src folder. However if you upgrade react-scripts to v1.0.11 it does let you access package.json.
I'm trying to get the version number from package.json in my app.
I've already tried these suggestions, but none of them have worked as I can't access package.json from outside the src folder (might be due to React, I'm new to this). Moving package.json into src then means I can't run npm install, npm version minor, and npm run build from my root folder. I've tried using process.env.npm_package_version but that results in undefined.
I'm using Jenkins, and I haven't set it up to push the commits up yet, but the only idea I have is to get the version from the tags in GitLab, but I have no idea how to do that, and it would add unnecessary dependency to the repo, so I would really like to find an alternative.
EDIT:
My file structure is like:
--> RootAppFolder
|--> build
|--> node_modules
|--> public
|--> src
|--> Components
|--> Root.js
|
|--> package.json
So to access package.json from Root.js I have to do import packageJson from './../../package.json' and then I get the following error:
./src/components/Root.js
Module not found: You attempted to import
./../../package.json which falls outside of the project src/
directory. Relative imports outside of src/ are not supported. You can
either move it inside src/, or add a symlink to it from project's
node_modules/.
Solving this without importing and exposing package.json to the create-react-app
Requires: version 1.1.0+ of create-react-app
.env
REACT_APP_VERSION=$npm_package_version
REACT_APP_NAME=$npm_package_name
index.js
console.log(`${process.env.REACT_APP_NAME} ${process.env.REACT_APP_VERSION}`)
Note: the version (and many other npm config params) can be accessed
Note 2: changes to the .env file will be picked only after you restart the development server
From your edit I would suggest to try:
import packageJson from '/package.json';
You could also try to create a symlink:
# From the project root.
cd src; ln -s ../package.json package.alias.json
List contents of src directory and you'll see the symlink.
ls
#=> package.alias.json -> ../package.json
Adding the .alias helps reduce the "magic" for others and your future self when looking at this. Plus, it'll help text editors keep them apart. You'll thank me later. Just make sure you update your JS code to import from ./package.alias.json instead of ./package.json.
Also, please take a look at this question:
The create-react-app imports restriction outside of src directory
Try this.
// in package.json
"version": "1.0.0"
// in index.js
import packageJson from '../package.json';
console.log(packageJson.version); // "1.0.0"
I don't think getting version by 'import' or 'require' package is correct.
You can add a script in you package.json
"start": "REACT_APP_VERSION=$npm_package_version react-app-script start",
You can get it by "process.env.REACT_APP_VERSION" in any js files.
It also works in build scripts, like this:
"build": "REACT_APP_VERSION=$npm_package_version react-app-script build",
import package.json
Generally speaking, importing package.json is not good. Reasons: security & bundle size concerns
Yes, latest webpack (default config) + ES6 import does tree-shaking (i.e. only includes the "version" value instead of the whole package.json) for both import packageJson from '../package.json' and import { version } from '../package.json'. But it is not guaranteed if you use CommonJS (require()), or have altered your webpack config, or use another bundler/transpiler. It's weird to rely on bundler's tree-shaking to hide your sensitive data. If you insist on importing package.json but do not want the whole package.json exposed, you may want to add some post-build checks to ensure other values in package.json are removed.
However the security concern here remains theoretical for open source projects whose package.json is public after all. If both security and bundle size are not problems, or, the non-guaranteed tree-shaking is good enough for you, then go ahead)
.env
The .env method, if it works, then it's good, but if you don't use create-react-app, you might need to install dotenv and do some additional configurations. There's also one small concern: it is not recommended to commit the .env file (here and here), but if you do the .env method, it looks like you will have to commit the file as it likely becomes essential for your program to work.
Best practice (arguably)
(this is not primarily for create-react-app, but you still can either use react-app-rewired or eject cra in order to configure webpack in cra)
If you use webpack, then with DefinePlugin:
plugins: [
new webpack.DefinePlugin({
'process.env.VERSION': JSON.stringify(
process.env.npm_package_version,
),
}),
]
You can now use console.log(process.env.VERSION) in your front-end program (development or production).
(You could simply use VERSION instead of process.env.VERSION, but it usually requires additional configuration to satisfy linters: add globals: {VERSION: 'readonly'} in .eslintrc (doc); add declare var VERSION: string; in .d.ts file for TypeScript)
Although it's "npm_package_version", it works with yarn too. Here's a list of npm's exposed environment variables.
Other bundlers may have similar plugins, for example, #rollup/plugin-replace.
Open your package.json file and change this line
Problem Is:
// in package.json
"scripts": {
"dev": "REACT_APP_VERSION=local REACT_APP_VERSION_NUMBER=$npm_package_version react-scripts start",
...
}
Solution is
// in package.json
"scripts": {
"dev": "react-scripts start",
...
}
I'd like to disable/not install one specific npm package in my app when CircleCI runs its tests, because the package makes the build process fail.
To be specific, it is a babel plugin for react-intl that automatically parses the files and pulls strings in another folder (babel-plugin-react-intl).
What is the best way of achieving this? Can this be done in the .babelrc file for example?
How you install and run tests locally should be the same as your CI setup.
If you need to disable a babel transform for tests - have them run as a different NODE_ENV and make sure your .babelrc only includes the plugin for the specific NODE_ENV
eg:
{
"env": {
"production": {
"plugins": ["react-intl"]
}
}
}
See: https://babeljs.io/docs/usage/babelrc/#env-option
I have read several times the documentation provided at :
Node API Babel 6 Docs
I'm starting out learning pg-promise following the Learn by Example tutorial and would prefer to work with ES6 and transpile to ES5 with Babel but am unsure of a few things :
After installing babel-core, what preset do I use and where/how do I configure this to work?
The documentation was unclear to me about which file I put: require("babel-core").transform("code", options); into and what parts of that code are place holders. When I use that code, do I just use it one time somewhere and then I can use ES6 in every other file? How would this be achieved?
I read about this .babelrc file and would like to confirm if the actual filename is ".babelrc" or if that is just the file extension and where in relation to the root directory of my project do I put that file.. and how do I link to it?
If I'm using pg-promise should I be using ES6 and Babel or will running : npm install as described under the Testing section for pg-promise be enough and trying to use ES6 with this create more problems?
I was hoping to take advantage of let and const if the need came up during my server side development.
Is there a standard file structure for a node+babel+pg-promise server setup?
Edit
Worth noting that I have also read Node JS with Babel-Node and saw that using this should be avoided. The final answer at the very bottom didn't really make sense to me for similar reasons I'm having trouble following the actual documentation provided by Babel.
1.a What Preset is needed?
You will need to install Babel firstly with npm install babel-core --save-dev in the root directory of your project using a Terminal window like Command Prompt.
Once installed, you will need to install the es2015 preset with npm install babel-preset-es2015 --save-dev. Babel-Core is Promises/A+ Compliant but not ideal for usage due to poor error handling so a library such as Bluebird should be used instead for this purpose. In order to transpile, babel-core will still need to be installed and es2015 enables ES6->ES5 transpiling so you can use fancy things like let and const etc.
1.b Where to put require("babel-core");?
instead, use require("babel-core/register"); and place it inside your Entry file typically called, "server.js". The server.js file will need to use CommonJS (ES5) exclusively.
By using the "require" statement it will apply all relevant transforms to all code being required into the Entry file and all files being required/included into those files.
You point to the Entry file inside package.json under the "main": section.
Package.json is created when you initialise the project with npm init at the root directory of your project inside the Terminal Window
One approach to this would be :
Entry File - server.js
server.js - requires {babel-core and the main ES6 file : config.js/jsx/es6/es}
config.es6 - uses ES6 and has includes(requires) for all other project files that can also use ES6 as they get transpiled by being loaded into the "config" file which is being directly transpiled by babel-core.
2. What is .babelrc?
.babelrc is the filename and should be placed in the same folder as your package.json file (normally the root directory) and will automatically "load" when babel-core is required to determine which preset(s) or plugins are to be used.
Inside .babelrc , you will need to add the following code :
{
"presets": ["es2015"]
}
3. pg-promise Testing Section
A direct quote from the developer recently answered this
You do not need to worry about steps in the Tests, use only the steps in the install. The one in tests relates to the dev dependency installation, in order to run tests. The pg-promise can work with any promise library compliant with Promises/A+ spec.
4. Standard File/Folder Structure for Server Side Projects?
There is no standard way to achieve this task as each project has unique demands. A good starting point would be to place the Entry file in the project root directory, the ES6 Config file in a "scripts" or "src" sub-folder and individual components in folders below that.
e.g.
ROOT/server.js
ROOT/src/config.es6
ROOT/src/component1/files.es6
ROOT/src/component2/files.es6
With this in place, Babel will successfully transpile all ES6 to ES5 and enable support of A+ compliant promises.
To begin using the node.js webserver This Guide provides a bit more insight and in the context of this answer the code shown would be placed into the ES6 config.es6 file and the following code would go into the Entry server.js file :
require("babel-core/register");
require("./src/config.es6");
The process for building Isomorphic web applications is different to this and would likely use things like grunt, gulp, webpack, babel-loader etc another example of which can be Found Here.
This answer is the combination of several key points provided by other answers to this question as well as contributions from experienced developers and my own personal research and testing. Thank you to all who assisted in the production of this answer.
This answer uses this simple directory structure
project/server/src/index.js => your server file
project/server/dist/ => where babel will put your transpiled file
Install babel dependencies
npm install -g babel nodemon
npm install --save-dev babel-core babel-preset-es2015
Add these npm scripts to your package.json file
"scripts": {
"compile": "babel server/src --out-dir server/dist",
"server": "nodemon server/dist/index.js
}
Create a .babelrc file in your project root directory
{
"presets": "es2015"
}
Transpile your directory with
npm run compile
Run your server with
npm run server
I think you should use a tool like grunt or gulp to manage all your "build" tasks. It will automate it for you, and you won't make errors.
In one command, you can transpile your code into babel ES2015 et start your application.
I suggest you to take a look at this simple project. (just install node_modules and launch npm start to start the app.js file)
However, if you really want to use babel manually,
.babelrc is the name of the file, you can see one in this project (redux) to have an example
.babelrc is a config file, if you want to see how it works, you can check this package.json (always redux)
There's actually no standard way that I know. You can use the project skeleton below if needed, and send pull request to improve it :-)
#makeitsimple
Step: 1
npm install nodemon --save
In project directory
Step: 2
yarn add babel-cli
yarn add babel-preset-es2015
Step: 2
In package.json-> scipts change 'start' to the following
start: "nodemon src/server.js --exec babel-node --presets es2015"
Step: 3
yarn start