Develop Reference

After I installed nodemon by "npm i nodemon" , when I tried to run it by "nodemon server.js" , it gives me this error. What should I do?

Screenshot form VS code terminalnodemon : The term 'nodemon' is not recognized as the name of a
cmdlet, function, script file, or operable program. Check the
spelling of the name, or if a path was included, verify that the
path is correct and try again.

I just meet that question.
First, you should make sure that you had installed nodemon in a global way (npm install -g nodemon), and make sure global package dir is in the environment variables.
Secondly, you should RESTART VScode if you are opening it now.
I spent lots of time to make sure the previous one, but it still fails, then when I restart VScode, everything is fine!

Try to install nodemon globally:
https://github.com/remy/nodemon
npm install -g nodemon
and edit Your package.json for example like that:
"scripts": {
"start": "node server",
"dev": "nodemon server"
},
then in terminal enter the command =>
npm run dev
It should works for You now ;-)
Good Luck and Best regards !

Below are some solutions
This is how you can install nodemon
npm install -g nodemon
after that you have to run this command: npm run dev
here dev is (script) server name like
{
"main": "app.js",
"scripts": {
"dev": "nodemon app.js"
},
}
after that if you are facing error like
" 'nodemon' is not recognized as an internal or external command,
operable program or batch file. "
Then after install nodemon globally write below command:
npm config get prefix
in output you will get PATH and then past this path in to the Environment Variables and it solved
Restart the terminal and run this command
nodemon run dev
I hope after that it will work properly :)

I just had to use npx instead of npm
for e.g. - npx nodemon <server.js>

Webpack pass env variables after build

My use case is the following. I make a production build like this:
cross-env API_URL=my_url yarn build
and then run it like this:
yarn start:prod
and it all works ok. But what I want to be able to do is:
yarn build
and then start it like:
cross-env API_URL=my_url yarn start:prod
so that I can test the same build against different backend environments. Is this doable?
Right now, if I try it, the API_URL doesn't get picked up after build and it defaults to the one I have in an .env file (because I support a default case). I'm aware that Webpack needs the env variables during build, but maybe there's a workaround I'm missing.
My build script, inside package.json is:
cross-env NODE_ENV=production env-cmd .env.prod --no-override --config config/webpack.prod.babel.js --color -p --progress --hide-modules --display-optimization-bailout
and my start:prod script is:
cross-env NODE_ENV=production env-cmd .env-prod --no-override node server

How to run Jasmine tests in watch mode for TypeScript

I have a Node.js app using TypeScript and now I want Jasmine to run tests automatically each time I make changes in .ts files. So I'm just trying to find an appropriate command to be run as npm test in command line or a package that can watch my .ts files compile them on changes and run jasmine. Does anybody know a solution for it?

The easiest way I found is
installing dependencies: npm install --save-dev jasmine-ts nodemon
initializing jasmine: node_modules/.bin/jasmine-ts init
In the package.json:
"scripts": {
"test": "nodemon --ext ts --exec 'jasmine-ts \"src/**/*.spec.ts\"'"
}
Edit: the above solution doesn't work as of the 11th of Apr, 2019. I published a modified working example at https://github.com/erosb/ts-node-jasmine-example

This may be done with two commands launched in separate terminals. Assuming packages are installed in global mode.
First command launches TypeScript compiler in watch mode:
tsc --watch
The second starts nodemon that watches .js files and restarts on changes. Each time it executes jasmine test runner:
nodemon --ext js --exec 'jasmine JASMINE_CONFIG_PATH=jasmine.json'
This solution is fast enough though it also has a drawback of running in two terminals. So it is not ideal but the best I've found so far.
As a result scripts section in package.json looks like:
"scripts": {
/* ... */
"watch": "tsc --watch",
"test": "nodemon --ext js --exec 'jasmine JASMINE_CONFIG_PATH=jasmine.json'",
"devstart": "nodemon ./bin/www"
},
devstart also works in couple with watch restarting server each time .ts files are changed (after they are compiled to .js).

You might consider using jasmine-node. I don't think that jasmine itself has a watch option.
npm i -g jasmine-node
Assuming that your test command in your package.json scripts block is something like this:
"scripts": {
...
"test": "jasmine some-directory-or-glob-pattern"
...
}
Use jasmine-node and add the --autotest and --watch flags to that command:
"scripts": {
...
"test": "jasmine-node --autotest --watch some-directory-or-glob-pattern"
...
}

Previously described methods either did not work, or were slow to compile code. Here is my attempt to solve this, both fast and convenient, works great for me. The only downside is that jasmine would not know which tests are affected by TS recompilation and would run all the tests.
yarn add tsc-watch --dev
yarn run tsc-watch --onSuccess "yarn run jasmine --config=jasmine.json"
NPM version:
npm -i tsc-watch
npm run tsc-watch --onSuccess "npm run jasmine --config=jasmine.json"
In my case I needed to correctly map TS paths. The full command looks like this:
yarn run tsc-watch --onSuccess \
"node -r tsconfig-paths/register node_modules/jasmine/bin/jasmine \
--config=jest/jasmine.json --require=dist/jest/setup.js $targetFile"
jasmine.json
{
"spec_dir": "dist/src",
"spec_files": ["**/*.e2e.js", "**/*.unit.js", "**/*.spec.js", "**/*.test.js"],
"env": {
"random": false
}
}
Just an example, please adjust to your needs.
tsc-watch starts a TypeScript compiler with --watch parameter, with the ability to react to successful compilation and start tests.

Watch template files and copy them to dist/ folder

I'm using typescript on my project and I can successfully watch + compile .ts files and output them to dist folder.
here is the scripts part of my package.json
"start": "npm run build && npm run watch",
"build": "npm run build-ts && npm run tslint",
"test": "cross-env NODE_ENV=test jest --watch",
"watch": "concurrently -k -p \"[{name}]\" -n \"Typescript,Node\" -c \"cyan.bold,green.bold\" \"npm run watch-ts\" \"npm run serve\"",
"serve": "nodemon dist/server.js",
"build-ts": "tsc",
"watch-ts": "tsc -w",
"tslint": "tslint -c tslint.json -p tsconfig.json"
The problem is I want to use js templating engine (nunjucks) and I need to watch the view files inside the views folder and move them to the dist folder.
Is there a way by just using npm scripts or nodejs?
Or do I need to use other tools like gulp or webpack?

I have the "same" request to for a CRUD graphql back-end server, but don't want to use gulp or webpack just to keep it simple.
I see that you use nodemon like me. Then, according the docs at https://github.com/remy/nodemon, it can be used it to monitor changes of any kind of file other than the default js. More over, nodemon can monitor the status of other transactional server other than node.
The first task is detecting the changes of wanted files: in my case I want copy the *.gql files in my src/schema folder to build/schema folder. For that, you can use the ext for the kind of files, and watch option for the source folder to explore.
The second one task is matter of copying the files. Naturally, you can use the copy command of your host OS. In my case I use the DOS xcopy command of the Windows shell (or cp in Unix like OS). nodemon has an "event-hook" with the event option, that can execute a command line when an event occurs. Just we need the restart event of the node server when the changes are detected for nodemon.
You can use the command line options, or a global config file, or in you local package.json project config file. I show up the last one using nodemonConfig section of package.json:
"nodemonConfig": {
"watch": [
"./src/schema",
"./build"
],
"ext": "js,gql",
"events": {
"restart": "xcopy .\\src\\schema\\*.gql .\\build\\schema /Y /O /R /F /I /V /E"
}
}

Ozkr's answer is great, I just want to add what worked for me, I had to change it a bit as nodemon was running into an infinite restart otherwise:
"nodemonConfig": {
"watch": [
"./views",
"./public"
],
"ext": "hjs,js",
"events": {
"restart": "cp -r views dist \n cp -r public dist"
}
}

copy-and-watch does just that:
I use this code to copy html files during development:
"copy_html": "yarn copy-and-watch src/mail_templates/* prod/mail_templates --watch --clean",

How to use node-inspector with `npm start` for my application?

I am using npm start to start my MEAN stack application, but I would like to use the node-inspector to debug some Mongoose. I know I can start the node inspector with node-inspector, but what can I substitute node --debug app.js with to make npm start work in my case?
This is my MEAN stack directory structure:
HTML views/
Angular.js public/javascript/
Express.js routes/
Node.js app.js
Mongoose js models/, connected in app.js
Mongo db connected in app.js
For more information, this is my related question.

You may want to add a seperate debug script to package.json. That way you won't have to remember to revert npm start when you're finished debugging.
"scripts": {
"start": "node ./bin/www",
"debug": "node --debug ./bin/www"
}
Start with npm run:
$ npm run debug

In package.json modify the start run command:
"scripts": {
"start": "node --debug app.js"
}

I use it like this, I also set a variable and run the inspector in one command:
npm run debug
"scripts": {
"start": "set SOAPAPI=https://example.com/&&nodemon",
"debug": "start node-inspector --web-port=8081&&set SOAPAPI=https://example.com/&&nodemon --debug"
}
*nodemon is an utility wrapper for node, you can use node instead