Title says it all. I want to be able to pass the argument to the middle of an npm script so that I may do the following.
$ npm run deploy -- <destination-path>
In package.json
"scripts": {
"deploy": "robocopy dist <destination-path> /E /NP"
}
Is this possible without using environment variables or npm's configuration variables?
Per Passing args into run-scripts #5518 it would appear that is it not possible to pass arguments to the middle of the script.
We are not going to support passing args into the middle of the script, sorry. If you really need this, write your test command using literally any of the command line parsers that anyone uses. (Minimist, dashdash, nopt, and commander all support this just fine.)
However, an alternative to this using the npm configuration block has been documented here. My implementation then looks like this:
"name": "foo"
"config": { "destination" : "deploy" },
"scripts": { "deploy": "robocopy dist %npm_package_config_destination% /E /NP" }
I can then override this on the command line and on my build server with:
npm run deploy --foo:destination=C:\path\to\deploy\dir
You can use an environment variable to set the destination path.
PATH=/path/to/file npm run deploy -- $PATH
or
export PATH=/path/to/file
npm run deploy -- $PATH
I have a different way to do that via shell.
If your npm command is:
"deploy": "robocopy dist ${1} /E /NP"
Where ${1} is the parameter you want to substitute.
Then wrap it in a function as follow:
"deploy": "func() { robocopy dist ${1} /E /NP";}; func"
then you can run a positional parameter substitution in shell as follow:
npm run deploy -- xyz
which would run
robocopy dist xyz /E /NP
And since this is a shell script, you can use default parameters as well:
"deploy": "func() { robocopy dist ${1:-xyz} /E /NP";}; func"
And you can use it as follows:
npm run deploy <==> robocopy dist xyz /E /NP
npm run deploy -- abc <==> robocopy dist abc /E /NP
You can make use of the arg structure of "sh -c". In my example below, I have to echo-feed the npm arg into a language parser. The argument for npm run foma <some word> will be in place of the $0:
"sayhello": "bash -c 'echo hello $0!"
A cross-platform solution I use is:
"arg-helper": "node -e \"process.stdout.write(require('child_process').execSync(process.argv[1].replace('$', process.argv[2] || '')))\"",
"sayhello": "npm run arg-helper \"echo hello $!\"
...
>npm run sayhello world
Levereging npm_config_* variables.
package.json
{
"scripts": {
"echoMyParam": "echo 'your param value is' $npm_config_foo"
}
}
Run
npm run echoMyParam --foo=bar
Result
your param value is bar
It's important to check the docs for other cases: https://docs.npmjs.com/using-npm/config
Related
I tried various solutions for this question but not able to pass 2 test cases amongst 4. Please help me crackdown this problem
Perform the below mentioned steps by creating package.json file named npm_commands in the maxbot directory
Create a file named index.js.
Write a js code in index.js file to create a string named myVar and value as node package manager
and convert it into uppercase.
NOTE: Please use console.log to display the output of myVar in index.js file
Configure scripts in package.json
(a) to check the versions of npm and node by using npm run release | tee output1.txt
(b) to execute index.js by using npm run build | tee output.txt
npm init - to initialize new package
give npm_commands as package name
give index.js as start file
Create new file named as index.js
declare : let myVar = "node package manager"
print var in uppercase: console.log(myVar.toUpperCase());
Add these scripts in package.json
to check npm and node version: "release": "npm -v && node -v",
to execute index.js file: "build": "node index.js"
Save and then run these commands to get the results:
npm run release | tee output1.txt
npm run build | tee output.txt
Step 1: run the command to initialize new package
npm init
Step 2: Command will start package initialization process
Set the package name:
package name: (challange) npm_commands
Step3: Press enter till time it ask for "entry point", by default it set to index.js verify and press enter key. Until the initialization process ends.
Step 4: Go to editor project explorer add create new file index.js, and add following code in it.
let myVar = 'node package manager';
console.log(myVar.toUpperCase());
Step 5: Add following lines into script block of package.json file
"release" : "npm -v && node -v",
"build" : "node index.js",
Script block looks like as below after adding above lines
"scripts": {
"release" : "npm -v && node -v",
"build" : "node index.js",
"test": "echo \"Error: no test specified\" && exit 1"
},
Step 6: Now open the command prompt and run the following commands
npm run release | tee output1.txt
npm run build | tee output.txt
Above commands create the output1.txt, and output.txt files in project explorer containing respective commands output.
Step 7: That's it! now run the test and check your FS_SCORE for 100% and submit the test.
With npm or yarn, is it possible for the script specified by an npm script to know the name of the npm script itself? For example:
"scripts": {
"foo": "echo Original command: $0",
"bar": "echo Original command: $0"
}
I'd like the result of those two scripts to be something like:
Original command: yarn run foo
Original command: yarn run bar
But all I actually get is: Original command: /bin/sh.
And in case it makes a difference, it's just the name of the script I need, not the yarn run part, so output like Original command: foo would be fine.
NPM adds the npm_lifecycle_event environment variable. It's similar to package.json vars.
*Nix (Linux, macOS, ... )
On *nix platforms npm utilizes sh as the default shell for running npm scripts, therefore your scripts can be defined as:
"scripts": {
"foo": "echo The script run was: $npm_lifecycle_event",
"bar": "echo The script run was: $npm_lifecycle_event"
}
Note: The dollar prefix $ to reference the variable.
Windows:
On Windows npm utilizes cmd.exe as the default shell for running npm scripts, therefore your scripts can be defined as:
"scripts": {
"foo": "echo The script run was: %npm_lifecycle_event%",
"bar": "echo The script run was: %npm_lifecycle_event%"
}
Note: The leading and trailing percentage sign % used to reference the variable.
Cross-platform (Linux, macOS, Windows, ... )
For cross-platform you can either:
Utilize cross-var to enable a single syntax, i.e. using the dollar sign prefix $ as per the *nix syntax.
Or, utilize the node.js command line option -p to evaluate and print the result of the following inline JavaScript:
"scripts": {
"foo": "node -e \"console.log('The script run was:', process.env.npm_lifecycle_event)\"",
"bar": "node -e \"console.log('The script run was:', process.env.npm_lifecycle_event)\""
}
Note In this example we:
Access the npm_lifecycle_event environment variable using the node.js process.env property.
Utilize console.log (instead of echo) to print the result to stdout
In an NPM project, I'd like to have a commit for each build version. This will allow me to go back to the current build version, fix a bug, without having to go through all the QA of a new version.
We can commit using npm scripts like this (see this answer):
package.json
"scripts": {
"git": "git add . && git commit -m",
}
Then invoke the script by running:
npm run git -- "Message of the commit"
I'd like to automate it to run after npm run build. For this purpose we can create a new command.
package.json
"scripts": {
"buildAndCommit": "npm run build && git add . && git commit -m",
}
This could be run using npm run buildAndCommit -- "commit for a new build"
The only thing left is that I'd like to identify this commit as one that could be linked to a commit. Is it possible to start the message automatically with "BUILD -" and to add to that the unique message which is passed in the command line? Something like:
package.json
"scripts": {
"buildAndCommit": "npm run build && git add . && git commit -'Build' + $uniqueMessageFromTheCommandLine`",
}
If it is not possible to template the string in package.json, how could I achieve it using a command line script? (Powershell is my command line tool).
Running on *nix platforms
On a *nix platform npm utilizes sh by default to execute the npm script(s). In this scenario you can simply use a shell function and reference the git message argument passed via the CLI using the $1 positional parameter.
Your npm script would be redefined like this:
"scripts": {
"build": "...",
"buildAndCommit": "func() { npm run build && git add . && git commit -m \"BUILD - $1\"; }; func"
}
Cross platform
Unfortunately, via Windows Powershell the solution is not quite as simple and terse.
When using Powershell npm utilizes cmd by default to execute npm script(s). Likewise npm utilizes cmd by default via other Windows consoles too, such as Command Prompt.
One way to achieve your requirement is to invoke a node.js via your npm script. The following provides two different methods that are essentially the same. Either will run successfully cross-platform (in your case via Powershell).
Method A - Using a separate node.js script
Create the following node.js script. Let's name the file script.js and save it in the root of the project directory, i.e. in the same directory where package.json resides.
script.js
const execSync = require('child_process').execSync;
const mssg = 'BUILD - ' + process.argv[2];
execSync('npm run build && git add . && git commit -m \"' + mssg + '\"', { stdio:[0, 1, 2] });
Explanation
The node.js builtin process.argv captures the argument at index two, i.e. the git commit message, that was provided via the CLI. The git commit message is concatenated with with the substring BUILD - to form the desired commit message. The resultant string is assigned to the variable mssg.
We then utilize the node.js builtin execSync() to execute your given npm script. As you can see, the value of the mssg variable is used as the git commit message.
The stdio option is utilized to ensure the correct configuration of the pipes, i.e. stdin, stdout, 'stderr', are established between the parent and child process.
Define your npm script named buildAndCommit as follows:
package.json
"scripts": {
"build": "...",
"buildAndCommit": "node script"
}
Above node invokes script.js.
Method B - Inline the node.js script in npm script
Alternatively, the aforementioned node.js script (i.e. script.js) can be provided inline in your npm script instead - therefore negating the use of a separate .js file.
package.json
"scripts": {
"build": "...",
"buildAndCommit": "node -e \"const mssg = 'BUILD - ' + process.argv[1]; require('child_process').execSync('npm run build && git add . && git commit -m \\\"' + mssg + '\\\"', { stdio:[0, 1, 2] })\""
}
This utilizes the same code from Method A albeit it slightly refactored. The notable differences are:
The nodejs command line option -e is utilized to evaluate the inline JavaScript.
process.argv this time will capture the argument, i.e. the git commit message, at index one in the array of arguments.
Additional escaping of the double quotes is necessary, i.e. \\\"
Running the npm script
Using either Method A or Method B run the command via your CLI as desired: For instance:
$ npm run buildAndCommit -- "commit for a new build"
This will produce the following git commit message:
BUILD - commit for a new build
I have some npm scripts that look like this:
"scripts": {
"exec:dev": "export NODE_ENV=development && npm run exec",
"exec:stage": "export NODE_ENV=stage && npm run exec",
"exec:prod": "export NODE_ENV=production && npm run exec",
"exec": "node myapp.js"
}
I'd like to pass some command line arguments to myapp.js but this does not work:
npm run exec:prod -- -a 123 -b 456
This is apparently due to the fact that the exec:prod script is calling the exec script and apparently not passing along the command line parameters. Is there any way to achieve this while keeping the nested script calls?
To explicitly tell the exec script to pass along the arguments it gets, include another --.
Instead of:
npm run exec:prod -- -a 123 -b 456
try:
npm run exec:prod -- -- -a 123 -b 456
The first double dash tells the exec:dev script, "these args
aren't for you, pass them along to the exec script".
The second double dash tells the exec script, "these args aren't
for you, pass them along to node myapp.js".
If you want to keep the npm run command that you enter via the CLI the same as per your question. (i.e. avoid adding yet another npm special option (--) to it, as per #MikePatrick 's answer).
Change your npm-scripts to the following instead:
"scripts": {
"exec:dev": "export NODE_ENV=development && npm run exec --",
"exec:stage": "export NODE_ENV=stage && npm run exec --",
"exec:prod": "export NODE_ENV=production && npm run exec --",
"exec": "node myapp.js"
}
Note: the npm special option (--) added to the end of the first three scripts.
Demo
For demonstration purposes, lets say myapp.js is as follows:
myapp.js
const args = (process.argv.slice(2));
const nodeEnv = process.env.NODE_ENV;
console.log(nodeEnv);
console.log(args);
Testing:
Running npm run exec:dev -- -a 123 -b 456 prints:
development
[ '-a', '123', '-b', '456' ]
Running npm run exec:stage -- -a 123 -b 456 prints:
stage
[ '-a', '123', '-b', '456' ]
Running npm run exec:prod -- -a 123 -b 456 prints:
production
[ '-a', '123', '-b', '456' ]
Further info
The docs for npm-run-script describe the npm special option (--) as follows:
... The special option -- is used by getopt to delimit the end of the options. npm will pass all the arguments after the -- directly to your script ... The arguments will only be passed to the script specified after npm run and not to any pre or post script.
I am unable to read parameters from package.json, so it's always $(directory).
and this is my command:
npm run migrate -- -directory "migration_dir"
package.json
{
"name": "XXXX",
"version": "0.1.0",
"description": "XXX",
"main": "app.js",
"scripts": {
"migrate": "cd $(directory)"
},
"keywords": [
"XXXX"
],
"author": "XXXX",
"license": "MIT"
}
Thank you.
The problem you may be facing is two-fold.
1. Arguments syntax for run-script
From npm docs:
As of npm#2.0.0, you can use custom arguments when executing scripts. The special option -- is used by getopt to delimit the end of the options. npm will pass all the arguments after the -- directly to your script:
npm run test -- --grep="pattern"
Arguments after -- will be passed directly, in your case that is
$ cd $(directory) -directory "migration_dir"
To fix that, you have to change your script definition accordingly:
"scripts": {
"migrate": "cd"
}
And pass the directory with no -directory option:
$ npm run migrate -- "migration_dir"
This will execute
$ cd "migration_dir"
2. Scripts are executing in a subshell
The migrate script you posted is useless because all npm scripts are executed in subshells, and changing the working directory from inside a subshell doesn't make a difference when a subshell exits.
Although if your script does anything beyond cd that will work:
"scripts": {
"foo": "cd / && pwd"
}
Part of the script after && will see the effect of cd, but your shell won't.
$ npm run foo
> cd / && pwd
/
$ pwd
/your/original/path
However, you can't specify additional arguments using -- anymore (npm run foo -- arg will do cd / && pwd arg).
It's look like You want to read a ENV parameter. Bash notation is ${directory} not $(directory).
Now You can run migration
directory="migration_dir" npm run migrate
The output is
cd migration_dir
Pros of this solution is possibility of use complicated scripts.