How to execute the start script with Nodemon - node.js

How can I execute the start script from a package.json file with Nodemon?

This will be a simple command for this
nodemon --exec npm start

In package json:
{
"name": "abc",
"version": "0.0.1",
"description": "my server",
"scripts": {
"start": "nodemon my_file.js"
},
"devDependencies": {
"nodemon": "~1.3.8",
},
"dependencies": {
}
}
Then from the terminal you can use npm start
Nodemon installation: https://www.npmjs.com/package/nodemon

I have a TypeScript file called "server.ts", The following npm scripts configures Nodemon and npm to start my app and monitor for any changes on TypeScript files:
"start": "nodemon -e ts --exec \"npm run myapp\"",
"myapp": "tsc -p . && node server.js",
I already have Nodemon on dependencies. When I run npm start, it will ask Nodemon to monitor its files using the -e switch and then it calls the myapp npm script which is a simple combination of transpiling the typescript files and then starting the resulting server.js. When I change the TypeScript file, because of -e switch the same cycle happens and new .js files will be generated and executed.

I use Nodemon version 1.88.3 in my Node.js project.
To install Nodemon, see in https://www.npmjs.com/package/nodemon.
Check your package.json, see if "scripts" has changed like this:
"scripts": {
"dev": "nodemon server.js"
},
server.js is my file name, you can use another name for this file like app.js.
After that, run this on your terminal: npm run dev

Use -exec:
"your-script-name": "nodemon [options] --exec 'npm start -s'"

In package json:
"scripts": {
"start": "node index",
"dev": "nodemon index"
},
"devDependencies": {
"nodemon": "^2.0.2"
}
And in the terminal for developing:
npm run dev
And for starting the server regularly:
npm start

First change your package.json file,
"scripts":
{
"start": "node ./bin/www",
"start-dev": "nodemon ./app.js"
},
After that, execute command
npm run start-dev

In package.json file. change file like this
"scripts":{
"start": "node ./bin/www",
"start-dev": "nodemon ./app.js"
},
and then execute npm run start-dev

Add this to script object from your project's package.json file
"start":"nodemon index.js"
It should be like this
"scripts": {
"start":"nodemon index.js"
}

Nodemon emits events upon every change in state; start, restart crash, etc. You can add a Nodemon configuration file (nodemon.json) like so:
{
"events": {
"start": "npm run *your_file*"
}
}
Read more in Nodemon events — run tasks at server start, restart, crash, exit.

If globally installed then
"scripts": {
"start": "nodemon FileName.js(server.js)",
},
Make sure you have installed nodemon globally:
npm install -g nodemon
Finally, if you are a Windows user, make sure that the security restriction of the Windows PowerShell is enabled.

I simply use 'npx' in the terminal to set up nodemon and execute it
npx nodemon

You can also install nodemon globally for frequent use:
npm i nodemon -g or sudo npm i nodemon -g
then edit your package.json:
"scripts": {
"start": "node index.js",
"dev": "nodemon index.js"
},
Generally, 'dev' specifies developmental use (npm run dev).

It will depend on types of your Nodemon installation. If you install Nodemon globally by using commands (npm install nodemon --global or npm install nodemon -g), you do not have to specify any script for Nodemon in your package.json file. Just executing command nodemon index.js will run your project.
But if you install Nodemon locally by command npm install nodemon then you have to specify the script. If you name it as start then npm run start or npm start will trigger the server to run.
// Absolutely no need for global installation
"scripts": {
"start": "nodemon index.js"
}

{
"name": "backend",
"version": "0.0.0",
"private": true,
"scripts": {
"start": "nodemon ./bin/www"
},
"dependencies": {
"bcrypt": "^5.0.1",
"cookie-parser": "~1.4.4",
"debug": "~2.6.9",
"express": "~4.16.1",
"hbs": "^4.1.2",
"http-errors": "~1.6.3",
"morgan": "~1.9.1",
"nodemon": "^2.0.12"
}
}
use "nodemon ./bin/www" scripts > start
eg:
"scripts": {
"start": "nodemon ./bin/www"
},

Try this, with watch:
nodemon --exec ts-node pathtoapp/filewithserver.ts -e ts
my project example: nodemon --exec ts-node src/server.ts -e ts

To avoid a global install, add Nodemon as a dependency, then...
package.json
"scripts": {
"start": "node ./bin/www",
"start-dev": "./node_modules/nodemon/bin/nodemon.js ./bin/www"
},

If you have nodemon installed globally, simply running nodemon in your project will automatically run the start script from package.json.
For example:
"scripts": {
"start": "node src/server.js"
},
From the nodemon documentation:
nodemon will also search for the scripts.start property in package.json (as of nodemon 1.1.x).

I know it's 5 years late, if you want to use nodemon.json you may try this,
{
"verbose": true,
"ignore": ["*.test.js", "fixtures/*"],
"execMap": {
"js": "electron ." // 'js' is for the extension, and 'electron .' is command that I want to execute
}
}
The execMap will execute like a script in package.json, then you can run nodemon js

You can use this instead of npm start :
npx env-cmd nodemon

You can do this one:
nodemon --exec ts-node src/app.ts
This will run the app.ts for you forever

First install package for nodemon as dev dependencies using
$ npm i nodemon -D
Then your package.json will have:
"devDependencies": {
"nodemon": "^2.0.20"
}
Then you can edit change package.json scripts part as
"scripts": {
"start": "node app.js",
"dev": "nodemon app.js"
}
Then you can use command:
$ npm run dev

You can also install nodemon as a development dependency:
npm install --save-dev nodemon or using yarn: yarn add nodemon -D.
With a local installation, nodemon will not be available in your system path or you can't use it directly from the command line. Instead, the local installation of nodemon can be run by calling it from within an npm script (such as npm start) or using npx nodemon.
In other words just run it with npx nodemon index.js

Just use the command : npx nodemon app.js
This is very simple ! and we can run the below command without altering the package.json file in your project

Related

nodemon, ts-node, not automatically recompiling

I am trying to create rest-api using, express+ts-node. I have done all setup based upon online tutorials, and when I run app using npm run dev it is working perfectly. But it is not restarting OnSave. This is my package.json script tag:
"scripts": {
"dev": "npm run nodemon src/index.ts",
"nodemon": "nodemon --watch 'src/**/*.ts' --ignore 'src/**/*.spec.ts' -r ts-node/register/transpile-only -r tsconfig-paths/register -r dotenv/config --exec ts-node --files src/index.ts",
"swagger": "tsoa spec"
},
Looks like nodemon not watching file changes. Please help, how to do restart on save.
try to install the ts-node-dev library then use this command in dev:

Why don't open the debugger ndb in package.json?

my packege.json
{
...
"scripts": {
"start": "nodemon server.js",
"start:prod": "NODE_ENV=production nodemon server.js",
"debug": "ndb server.js"
}, ...
npm ndb is global now.
when run npm run debug but don't open the debugger ndb. What is the problem or any trick?
Well I had the same problem with my Linux(arch), it was because of visual studio code blocking the same files when it's open.
try to run with it after closing vscode or other editor, because it could be blocking some files to read with ndb.

Using Nodemon or something similar to listen for changes, first build, then start?

Using Nodemon or something similar to listen for changes, first build, then start? Is it possible?
"scripts": {
"build": "npm run build:dll && webpack --progress",
"start": "node app.js",
}
Make sure nodemon is installed (npm install -g nodemon or npm install --save-dev nodemon) and then just change your package.json to this:
"scripts": {
"build": "babel lib -d build --copy-files",
"start": "nodemon build/index.js"
}
EDIT:
Add a nodemon.json on the root of your project, in there insert your build script in the "events.restart" section as documented here: https://github.com/remy/nodemon/blob/master/doc/sample-nodemon.md
"events": {
"restart": "your build script here"
}
And finally run with "npm run start". This run your app with nodemon and nodemon's configuration will execute your build very time you change your code (on restart)

'ts-node' is not recognized as an internal or external command, operable program or batch file

I'm getting error in my Vs Code terminal and command prompt that 'ts-node' is not recognized as an internal or external command, operable program or batch file. while i'm trying the start command in the terminal npm run dev and i have added my package.json file also.
{
"name": "tsnode",
"version": "1.0.0",
"description": "ts-node experiment.",
"scripts": {
"dev": "nodemon --exec 'ts-node --cache-directory .tscache' ./server.ts",
"start": "ts-node --fast ./server.ts"
},
"author": "Mugesh",
"license": "ISC",
"dependencies": {
"#types/body-parser": "^1.16.3",
"#types/chalk": "^0.4.31",
"#types/express": "^4.0.35",
"#types/node": "^7.0.18",
"body-parser": "^1.17.1",
"chalk": "^1.1.3",
"express": "^4.15.2",
"nodemon": "^1.11.0",
"ts-node": "^3.0.4",
"typescript": "^2.3.4"
}
}
You need to install ts-node as global
npm install -g ts-node
More information
https://github.com/TypeStrong/ts-node
I wouldn't recommend relying on globally installed ts-node in your own module as some of the answers here suggest.
If you do that then anyone who installs your module would need to install ts-node globally as well (just a usual npm install would not be enough) and then you will have a problem if two modules need things like ts-node globally installed but with different versions etc.
To avoid that, all your dependencies should be defined in your package.json and installed locally in node_modules.
There is a little-known command npx that is used to run binaries from modules that are installed locally in node_modules.
For example, see what happens when I install (locally) ts-node and typescript:
rsp#mn-r:~/node/test/ts-test-1$ npm i ts-node typescript
npm WARN ts-test-1#0.0.0 No description
npm WARN ts-test-1#0.0.0 No repository field.
+ ts-node#6.0.3
+ typescript#2.8.3
added 19 packages from 44 contributors in 2.157s
[+] no known vulnerabilities found [19 packages audited]
and then I try to run ts-node:
rsp#mn-r:~/node/test/ts-test-1$ ts-node -v
-bash: /Users/rsp/opt/node/bin/ts-node: No such file or directory
I can run it with npx:
127!rsp#mn-r:~/node/test/ts-test-1$ npx ts-node -v
ts-node v6.0.3
node v10.1.0
typescript v2.8.3
or I could give the path explicitly:
rsp#mn-r:~/node/test/ts-test-1$ ./node_modules/.bin/ts-node -v
ts-node v6.0.3
node v10.1.0
typescript v2.8.3
In any case, I don't need to install anything globally.
I just encountered a similar issue: on Mac OS --exec ts-node works, on Windows it doesn't.
My workaround is to create a nodemon.json like this:
{
"watch": "src/**/*.ts",
"execMap": {
"ts": "ts-node"
}
}
and change the package.json scripts section to
"scripts": {
"start": "nodemon src/index.ts"
},
The only solution that worked for me:
"start": "nodemon --exec npx ts-node ./index.ts",
I ran into the same problem and found that it works by using double quotes instead of single.
"dev": "nodemon --exec \"ts-node\" --cache-directory .tscache ./server.ts"
P.S. This is 1 year after the problem. Not sure if package versions are a factor. Will confirm if needed.
If you work under Windows you can't use single quote in the json file. That is why you have to replace all single quote symbols(') by the double quote symbols(").
But between two double quotes(") you have to use escaped double quote(").
For the current case you have to change the row in the file package.json:
"dev": "nodemon --exec 'ts-node --cache-directory .tscache' ./server.ts",
into the row:
"dev": "nodemon --exec \"ts-node --cache-directory .tscache\" ./server.ts",
Nodemon is for watching and rerunning node processes when files change. The local ts-node installed in the node_modules directory is not recognized in the scope of the --exec argument. To get around this, some people have recommended installing ts-node globally. As a user pointed out, that's not a good solution because it relies on packages external to your project and makes the ts-node in our node_modules pointless.
Edit:
With newer versions of nodemon, you can simplify this even further (note: you still need ts-node installed as a devDependency).
"start": "nodemon src/index.ts"
Previous:
To fix your solution, prefix ts-node with the npx helper, which will use your local node_module executables.
package.json, inside the scripts block:
"start": "nodemon --watch './src/**/*' -e ts --exec 'npx ts-node src/index.ts'"
An alternative approach could be to use the typescript watcher with the existing node command and the concurrently package.
"start": "concurrently \"tsc --watch\" \"node ./dist/index.js\""
Same principle. One package watches for changes (nodemon & tsc) and restarts the second process (the node/ts-node server).
Edit 11/17/2021:
I returned this post to use it as a reference for setting up a prototype build and found the nodemon approach above was no longer working, it was now throwing the error:
''npx' is not recognized as an internal or external command,
operable program or batch file.
I found a fix was to convert all single quotes to escaped double quotes.
"start": "nodemon --watch \"./src/**/*\" -e ts --exec \"npx ts-node src/index.ts\""
Guess something changed since I my original post. Hope that helps!
For me deleting node_modules and installing it again using npm i was enough.
I had the similar problem, but I have resolved by replacing
"dev": "nodemon --exec 'ts-node --cache-directory .tscache' ./server.ts",
to
"dev": "nodemon --exec ts-node --cache-directory .tscache ./server.ts",
Just remove the single quote(') and install ts-node globally
I had a similar problem while using nodemon:
I had nodemon installed globally, AND ts-node only installed locally.
Solution:
I installed ts-node globally (still keeping the local dependency).
I fixed the issue by removing single quorts around ts-node. as per below
"dev": "nodemon --watch 'src/**/*.ts' --exec 'ts-node' src/index.ts"
updated as
"dev": "nodemon --watch 'src/**/*.ts' --exec ts-node src/index.ts"
please note. my environment is windows 10 and npm version6.14.4
Like suggested in some answers, you should install ts-node locally and not globally. npx makes it easy to use CLI tools and other executables hosted on the registry as explained here. Hence, can be used to run ts-node on your terminal and even scripts from your package.json file. For example;
Take this to be my package.json file
{
...
"scripts": {
"start": "npx nodemon path/to/file"
}
}
Now running npm run start would not give any more issues.
You can try the following command
"dev": "nodemon --watch './**/*.ts' --exec \"ts-node\" src/index.ts"
This worked for me .
If your ts-node isn't working, as an alternative you can do the following:
1) Install nodemon locally --> npm i nodemon
2) In your package.json 'scripts' add the following:
"scripts": {
"start": "nodemon index.ts",
"test": "echo \"Error: no test specified\" && exit 1"
},
3) Now run npm start (this will automatically run node for you, but this WILL NOT COMPILE TS )
4) Open a new tab in the terminal/command line, cd the folder your working in and run tsc index.tsc --watch
This will compile your typescript. The only downside is you will just have to have both tabs open, one for running node automatically and the other for compiling automatically, but this works.
I was having the same issue on windows. I found the solution for my issue was resolved when I corrected some misplaced '
Originally:
"scripts": {
"dev": "nodemon --watch 'src/**/*.ts' --exec 'ts-node' src/index.ts",
"build": "tsc",
"start": "node dist/index.js"
}
Fixed:
"scripts": {
"dev": "nodemon --watch 'src/**/*.ts' --exec \"ts-node\" src/index.ts",
"build": "tsc",
"start": "node dist/index.js"
}
The difference in case it isn't clear is that I no longer wrap ts-node in '
* EDIT *
I changed this based on the answer from #RoutesMaps.com above. This solved my problem as well as removing the ' but #RoutesMaps.com actually explains the issue resolution
I ran this command after npm install ts-node.
This fixed my problem:
npm install -D tslib #types/node
yarn add -D ts-node
"scripts": {
"start": "ts-node src/index.ts"
}
'yarn start' now works
Found the answer.
Without installing ts-node globally, just create inside your project nodemon.json file and put it there :
{
"execMap": {
"ts": "node --loader ts-node/esm"
}
}
So now, you can keep type:"module" in your package.json and module:"ESNEXT(or smth that supports ES Modules)" in your tsconfig.json. However, you are going to get constant warning from nodemon that it's, I mean loader type, experimental feature but it's not critical.
In your package.json, in dev command for example just run nodemon path/filename.ts
If you are using a mac these are the steps I came up with in order to fix this in the terminal.
Install globaly and use the returned file path with the symlink ‘ts-node’ and move this file into /usr/local/bin
Install locally without saving to package.json
copy folder in /node_modules into /usr/local/lib/node_modules/
Make sure the file is executable by opening /ts-node/dist and using the command chmod +x bin.js
run npm i in ts-node folder
Make sure that dist folder still exsists, if not copy it back over.
Test running ts-node in terminal, if it does not work it will return an error of which module needs to be moved over to ../
After ts-node runs be sure to delete the folder /usr/local/lib/node_modules/ts-node/node_modules
I was having the same issue. I found the solution for my issue was resolved when i do simply run this command first "npm run build" and than try it nodemon and also add in package.json
"scripts": {
"test": "echo \"Error: no test specified\" && exit 1",
"build": "tsc",
"dev": "ts-node ./lib/server.ts",
"start": "nodemon ./dist/server.js",
"prod": "npm run build && npm run start"}
If you are using code-runner in vs-code then edit setting.json file
"typescript": "tsc $fileName && node $fileNameWithoutExt.js "
Write the the script like this inside your package.json file
"scripts": {
"test": "echo \"Error: no test specified\" && exit 1",
"build": "rimraf ./build && tsc",
"start": "node build/index.js",
"tsc": "tsc",
"watch-node": "nodemon build/index.js",
"postinstall": "npm run tsc"
},
Then, npm run build
and finally npm run start
I encountered the same error when trying to run nodemon from a Git Bash but it seems to be working just fine when running nodemon from PowerShell. So, you should consider giving some other terminals a chance.
Me helped this command
npm i -D typescript
More specifically written there https://nodejs.dev/learn/nodejs-with-typescript
Please use TSC --init, instead of TS --init
this error can occur if you have one version of ts-node installed in your project and another version globally.
To solve the problem - install the same version of the package
Just had this same problem and came up with a hybrid solution, using npx to execute but via nodemon config (rather than package.json).
nodemon.json...
{
"watch": ["src"],
"ext": "ts",
"exec": "npx ts-node ./src/server.ts"
}
Actually if you install nodemon as globally then install ts-node also globally. If you install nodemon as -D (dev dependency) then install ts-node as dev dependency. It will work.
A bit late to the party, but my issue was that I had set the NODE_ENV=Production environment variable on my CI. When NODE_ENV is set the dev dependencies(where the ts-node was listed) won't be installed.
Removing NODE_ENV fixed the issue.
I removed it from dev dependencies and added it to dependencies. That solved the problem for my case.

How do I execute typescript watch and running server at the same time?

I was developing my project in nodejs. I found if I need to code and test api, I will run two console, one is to execute typescript watch, another is to execute server.
I think it's so troublesome. I find other developers on github have written scripts in package.json. It's easy to call any commands. It attracts how to write the scripts and simply my development workflow.
In short, the comand of typescript watch is tsc -w and the comand of running server is node app.js. My idea is merge the commands as tsc -w & node app.js but I can't work the two commands at the same time. How do I do? Thanks.
My idea is merge the commands as tsc -w & node app.js but I can't work the two commands at the same time. How do I do
You have a few options. Simplest is to use ts-node-dev : https://github.com/whitecolor/ts-node-dev
Option 1
Step 1
install concurrently, use npm, pnpm or yarn
pnpm i concurrently -D
Step 2
create a script with this command
"scripts": {
"run": "tsc && concurrently \"tsc -w\" \"nodemon dist/app.js\"",
}
Option 2
without install anything (mac or Linux)
"scripts": {
"run": "tsc -w & nodemon dist/app.js",
}
run tsc first so that your directory has something at the time of running node
And with that you will have running your Typescript application 🚀
Another option can be to use nodemon:
tsc -w & nodemon app.js
Since Typescript 3.4 the compilation is faster because you can use the incremental compiler option and they keep improving (including interesting changes for large projects in 3.8).
Update:
I also moved to use concurrently as HerberthObregon says in his answer
TLDR, If you like nodemon this is a straight forward way to get file watch, compilation and execution:
nodemon --ext ts --exec 'tsc && node dist/index.js'
Optionally replace tsc with babel for faster compilation.
Here is a more complete example, in package.json (with source maps):
"scripts": {
"develop": "nodemon --ext ts --exec 'yarn build --incremental && yarn serve'",
"build": "tsc",
"serve": "node --require source-map-support/register dist/index.js",
...
},
Install source-map-support as a dependency if you want, ahem... source map support! Otherwise, remove --require source-map-support/register from the serve script above.
tsconfig.json
{
"compilerOptions": {
...
"sourceMap": true,
"outDir": "dist",
}
}
Building on herberthObregon's answer
Step 1: Install packages
npm install concurrently typescript nodemon --save-dev
Step 2: Create these scripts in package.json
"scripts": {
"build": "tsc",
"build:watch": "tsc -w",
"dev": "npm run build && concurrently \"npm run build:watch\" \"npm run serve:watch\"",
"serve": "node dist/index.js",
"serve:watch": "nodemon dist/index.js"
},
build runs a standard typescript build
build:watch runs typescript build in watch mode
serve serves up your node project (assuming your tsconfig outputs to dest/index/js)
serve:watch uses nodemon to restart the node server whenever the js output changes
dev puts them all together
Just going to throw my hat in here, here's a solution using ts-node-dev and concurrently, similar to the one provided by #HerberthObregon but using ts-node-dev instead of nodemon:
"scripts": {
"start": "npm run build && concurrently \"npm run build:watch\" \"npm run dev\"",
"dev": "tsnd --respawn src/main.ts",
"build": "tsc -p tsconfig.release.json",
"build:watch": "tsc -w -p tsconfig.release.json"
}
Bonus: If you need help with your figuring out tscand your tsconfig.json, I use the sensible defaults from this node typescript starter.
Here's a solution that works for me
1. Install ts-node and nodemon as dev dependencies
2. Create a script : "dev" : "nodemon app.ts"

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