js-submodule

Single version for all submodules as there is a single package which is published to registry

How to use this demo

npm pack . # packs this module into package
cd ./client-app

npm install --omit=optional ../js-submodule-1.0.1.tgz
node index.js

client app uses only node-fetch subpackage, though js-submodule depends on both node-fetch and axios. In this case, axios is never loaded, so client-app defacto does not depend on it. But if it's also possible to depend on both, for this client-app just needs to add axios to its dependencies and import js-submodule module.

General details

A package which contains 2 submodules:

• request based on node-fetch
• request based on axios

Both dependencies are listed as optional dependencies. To ensure that optional dependencies are not installed on app level, app level npm install should look like this:

npm install --omit=optional

Previously it was possible to use optional peerDependencies (still possible) but now npm has a bug, it installs optional peer dependencies automatically (npm/cli#2744). It doesn't hurt much, it still properly resolves version (relies on client-app version if it's in specified range) but we will cache all of those in our CI caches and it's just a waste of disk space and time during installation.

But instead of optional dependencies, it's possible to use optional peerDependencies this way:

{
    "name": "js-submodule",
    "peerDependencies": {
        "axios": "^1.0.0",
        "node-fetch": "^3.0.0"
    },
    "peerDependenciesMeta": {
        "node-fetch": {
            "optional": true
        },
        "axios": {
            "optional": true
        }
    }
}

Adding --legacy-peer-deps probably should help to overcome the bug mentioned above (but I haven't tested this). Bug is few years old and unlikely will be fixed in foreseen future because optional dependencies is more an edge case than a common thing and doesn't influence many packages.