Pfthb

I am writing a library in NodeJS that will be used by others. This library has tests which depend on a testing framework, so this framework is listed in the devDependencies section of package.json so that anyone pulling my library into their code won't have my test framework downloaded and then ignored.

However I also have a command-line interface to the library, which should be installed if someone chooses to install the library globally, but should also be ignored when someone else pulls the library into their own project. This CLI has some dependencies, so I am trying to work out where to list them such that they are pulled in when installing globally (or during development work on the library itself) but ignored when another project pulls the library in as its dependency.

• If I list the CLI dependencies in the main dependencies section, then users of the library will get these all pulled in to their own code even though they will never use the CLI, so this is definitely the wrong spot.




• If I list them as devDependencies then they will be left out of other projects which is ideal, however if anyone tries to install the library globally with --production then the CLI dependencies will be omitted and the CLI won't work, even though in this case a 'production' install should definitely include the CLI.




• bundledDependencies doesn't look like what I'm after as I don't want to include the CLI dependencies in any bundles, as those are most likely to be the cases where the CLI will not be used.




• peerDependencies does not seem relevant in this case.




• optionalDependencies doesn't seem ideal because if the CLI dependency fails for whatever reason then the global install will proceed but the CLI won't work, which is kind of the point of installing it globally.




• Moving the CLI into a separate package could also be an option, however the CLI is crucial during library development so having it as part of a separate package would make development much harder, so it's something I'd like to avoid.

It looks like devDependencies is the only option, however because it has some limitations I would like to confirm that there really is no better option before proceeding with this!

I think the best approach is to have the CLI in a separate package, similar to express-generator which is a CLI for express.

Even if it's crucial for development, your library users would need to type just one extra command, npm install library-cli, and if this is properly documented I don't see any problems.

You could also add a postinstall script or a custom script to your main library that installs the CLI after the package is installed:

"scripts": 
 "postinstall": "npm install -g library-cli"

However it's also fine if you chose to bundle your CLI with the main library, however in this case you should not put the CLI dependencies into devDependencies. All the modules that are required to run the cli should go into dependencies even if 90% of the users would never use them.

devDependencies should be used for all the tools that are required in the build process, like minification, tests, typescript etc. Everything that is required at runtime for your CLI should go into dependencies.