When executing a NodeJS App in the command prompt, you usually do this:
node myscript.js
Is it possible to do something like this?
node http://www.myhostedsite.com/myscript.js
I'd use wget http://www.myhostedsite.com/myscript.js && node myscript.js to avoid the differences in the REPL (such as _ being a reference to the last return value, which can break libraries like underscore.js).
You've also tagged socket.io in your question, which implies you might need some dependencies to be available as well. In that case you may need to install those dependencies globally with npm install -g <dependency name> in order for the script to run successfully.
Related
Goal
I want to use jsdocs with npm.
Background
I am new to npm and its plugins. Recently I found out about jsdoc and I tried using it, with no success.
What I tried
First I installed the package using npm's command npm install --save jsdoc, and the install completed successfully.
However, when I try to use it in my project (I am inside the project's folder) I type jsdoc example.js and I get the following error:
/home/ubuntu/.nvm/versions/node/v4.4.5/bin/jsdoc: No such file or
directory
This leads me to think that:
I am in the wrong directory. If so, where should I be? (other than the project root folder)
The installation had a problem, even though it was successfull.
I have also tried to run npm jsdoc example.js but I get another error (this time from npm, saying I am not using it correctly).
I also installed jsdoc globally (using the -g flag) and it worked, but I truly want to avoid this because not all projects are using jsdoc.
Summary
To conclude, I am looking for a way to run jsdoc locally to a project with npm. Does anyone know of a way to do this?
To run jsdoc in the command line, the location of the jsdoc needs to be known. So when you have installed jsdoc globally, system would be able to find the file.
However if you want to run it locally, you need to include the file location before the jsdoc command.
For example, try using ./node_modules/jsdoc/jsdoc.js example.js
There's an error being thrown in of my node.js projects, and the stack trace doesn't seem to point back to any of the libraries I'm using, is there a simple method of finding out what packages depend on this package in my node_modules directory?
Ideally this method doesn't involve manually checking the package.json of every module in my node_modules directory.
Use npm ls <module-name>.
You can use a bit of bash scripting to automate this
who_depends_on() {
local dependency=$1;
for file in $(ls node_modules); do
local match=$(grep $dependency "node_modules/$file/package.json");
if [[ $match ]]; then
echo "'$file' is dependant in '$dependency'";
fi
done
}
Put the function wherever you store your shell functions, and then run like so
who_depends_on "your-package-here"
The main caveat with this package is it'll pick up the package.json package you're looking for as well.
How to configure package.json in such way that a dependency available globally will not be installed again locally?
For example, I have a project with jshint listed as dev-dependency; however, I already have jshint installed globaly and I want this module to use the global jshint.
Not sure what you are trying to do, but in any case using global dependencies in the code is not a preferred way.
To get some information, type npm help folders, here's tl;dr part:
Local install (default): puts stuff in ./node_modules of the current package root.
Global install (with -g): puts stuff in /usr/local or wherever node is installed.
Install it locally if you're going to require() it.
Install it globally if you're going to run it on the command line.
If you need both, then install it in both places, or use npm link.
So, in your case, the last item, link, is the answer: https://docs.npmjs.com/cli/link.
You need to run npm link jshint in your base folder. It'll link node_modules/jshint to the global one. This will create a symbolic link to the binary file, however, you can't use it in require() at some point of your code. As explained above, global packages are to run on command line so they are binary files.
After all I ended up using npx for things that need to be installed globally, for example, npx standard in npm scripts. Works regardless global presence.
Just earlier, I posted my question:
https://stackoverflow.com/questions/28336443/how-to-not-put-my-js-files-in-user-myuser-for-node-js
I have a file, hello.js, located in /Users/MyUser/Desktop/Node/
I can see that my default directory is /Users/MyUser/
Okay, so I get that I need to change my working directory. What I have been able to find so far is to use >process.chrdir('/Users/MyUser/Desktop/Node/');
Cool, that works, but now when I get out of the REPL shell, the directory resets.
The person who responded to my question said that I needed to run >node init and later npm install <name of dependency> --save
My first question: I have ran >node init and see that I can create this package.json file, what does this do exactly?
Secondly: I was told that I need to add dependancies. Could someone please explain to me what this means in Node terms? Does a dependancy simply mean a folder that I want node to include? Do I want to add this Node folder on my Desktop to be able to run my scripts?
I am currently trying to go through the learnyounode courses, however I do not want to have to save all of these test files in my /User/MyUser directory, so any advice would be greatly appreciated.
Thanks
I have ran >node init and see that I can create
this package.json file, what does this do exactly?
npm init is used to create a package.json file interactively. This will ask you a bunch of questions, and then write a package.json for you.
package.json is just a file that handle the project's dependencies and holds various metadata relevant to the project[ project description, version, license information etc]
I was told that I need to add dependencies. Could someone please
explain to me what this means in Node terms?
Lets say you're building an application that is dependent on a number of NPM modules, you can specify them in your package.json file this way:
"dependencies": {
"express": "2.3.12",
"jade": ">= 0.0.1",
"redis": "0.6.0"
}
Now doing npm install would install a package, and any packages that it depends on.
A package is:
a folder containing a program described by a package.json file
a gzipped tarball containing (1)
a url that resolves to (2)
a # that is published on the registry with (3)
a # that points to (4)
a that has a "latest" tag satisfying (5)
a that resolves to (2)
If you need to install a dependency that haven't been included in package.json, simply do npm install <packageName>. Whether or not you want to include this newly installed package in package.json is completely your take. You can also decide how this newly installed package shall appear in your package.json
npm install <packageName> [--save|--save-dev|--save-optional]:
--save: Package will appear in your dependencies.
--save-dev: Package will appear in your devDependencies.
--save-optional: Package will appear in your optionalDependencies.
Does a dependency simply mean a folder that I want node to include?
Umm, partly yes. You may consider dependencies as folders, typically stored in node_modules directory.
Do I want to add this Node folder on my Desktop to be able to run my
scripts?
No, node manages it all. npm install will automatically create node_modules directory and you can refer to those dependencies with
require() in your .js files
var express = require('express');
Node REPL simply provides a way to interactively run JavaScript and see the results. It can be used for debugging, testing, or just trying things out.
process.cwd() points to the directory from which REPL itself has been initiated. You may change it using process.chdir('/path'), but once you close the REPL session and restart, it would always re-instantiate process.cwd() to the directory from which it has been started.
If you are installing some packages/dependencies in node project1 and think those dependencies can also be useful for node project2,
install them again for project2 (to get independentnode_modules directory)
install them globally [using -g flag]. see this
reference packages in project2 as
var referencedDependency = require('/home/User/project1/node_modules/<dependency>')
Simply doing process.chdir('/home/User/project1/node_modules/') in REPL and referencing as
var referencedDependency = require('<dependency>') in your js file wont work.
>process.chdir('/Users/MyUser/Desktop/Node/'); change the working directory only for that particular REPL session.
Hope it helps!
This has nothing to do with node.js but is rather inherent in the design of Unix (which in turn influences the design of shells on other operating systems).
Processes inherit values from their parent's environment but their environments are distinct.
That terse description of how process environments work has a sometimes unexpected behavior: you cannot change your parent's environment. It was designed this way explicitly for security reasons.
What this means is, when you change the working directory in a process and quits that process your shell's working directory will not be affected. Indeed, your shell's working directory isn't affected even when the process (in this case, node REPL) is running.
This exact question is often asked by people writing shell scripts wanting to write a script that CDs into someplace. But it's also common to find this question asked by people writing other languages such as Perl, Tcl, Ruby etc. (even C).
The answer to this question is always the same regardless of language: it's not possible to CD from another program/script/process.
I'm not sure how Windows handles it so it may be possible to do it there. But it's not possible on Unixen.
So I'm attempting to do this Node.js tutorial, and it says to create three .js files from the command line.
touch server.js client.js test.js
Except I get the following error:
'touch' is not recognized as an internal or external command, operable
program or batch file.
Not sure what is wrong here. I've installed Node.js as well as npm and browserify. I've created the package.json file correctly.
I suppose I could go into the project directory, right click and make a new file that way, but that defeats the purpose doesn't it?
What is the actual command to create a new file in the command line?
I'm using Windows 7.
That command is for a unix environment. You can use the following to create an empty file with similar functionalities that touch has in windows:
echo $null >> server.js in the desired directory
You can use the following command:
echo> index.js
touch is generally present on *nix platforms but not Windows. You will be able to follow the tutorial without it.
The tutorial author is using it to create empty files. You could achieve the same by simply saving files with the same names using an editor.
Alternatively, if you really want to use it in Windows, try Cygwin.
I know this is an old post, but the question is still relevant and there is a way to integrate the touch command into Windows, using the touch-for-windows npm package. It can be installed globally via node/npm with npm install -g touch-for-windows.
As someone who uses a pretty customized terminal across multiple machines, Cygwin didn't provide some of the other features I often use. The echo command (and accepted answer) provided by ltalhouarne works, but I felt was cumbersome to use. This npm package, though old, operates exactly in Windows as the touch command in *nix.
You can use :
copy nul > Gulpfile.js
You can also use the following command:
copy con [filename.extension]
[Note: Don't include square brackets]
That's it!
Follow the link
For installation in Windows
https://www.npmjs.com/package/touch-for-windows
Installation
In command prompt type:
npm install -g touch-for-windows.
Usage
After installing, you can run this application via the command line, as shown below.
C:\pythonapp>touch index.html
Successfully created 'index.html'
Worked for me
cd > filename.txt works too... if u create txt files, then it will have the file path on them. Just remember to delete them.
If you want a cross-platform solution in an environment where you have Node.js installed, you can as well run javascript code with node:
node -e "require('fs').writeFileSync('server.js', '')"
node -e "require('fs').writeFileSync('client.js', '')"
node -e "require('fs').writeFileSync('test.js', '')"
The commands above will create your 3 files with no content. You can also replace the '' by any content you would like to have in the file.
For more complex logics, you can move your code into a javascript file and execute it like:
node path/to/script.js
If you use git, there is already a bash installed inside
c:\Program Files\Git\bin\bash.exe
You can use it to work without installing cygwin. It contains the touch command.
Use the below command example to create any file in cmd:
type NUL > index.js
(here index.js is the file I want to create)