fix: read npm registry from npm config

[lambourn]

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What is the current behavior?

nativescript-cli assumes that npmjs.org is used. If another (local) repo like artifactory is used, tns add platform (and probably other steps) fails as it hard-wired tries to pull packages from npmjs.org

What is the new behavior?

read npm registry from npm config instead of hard-wiring it to npmjs.org, fixes #3866

[rosen-vladimirov]

run ci

[rosen-vladimirov]

What do you think about falling back to registry.npmjs.org in case npm config get registry fails for some reason?
For example:

let registry = "https://registry.npmjs.org/";
try {
    registry = await this.$childProcess.exec(`npm config get registry`);
} catch (err) {
    this.$logger.trace("Unable to get information for current npm registry", err);
}

const url = registry.trim() + packageName;

[lambourn]

I thought about this as well - defensive programming FTW ;-) But even if I wipe my .npmrc file, the value npm defaults to is always https://registry.npmjs.org/

Plus, if npm config get registry fails, then something is foul with npm installation in general.

[rosen-vladimirov]

Ok, thanks for the explanation. We'll run our tests now and if the build is green, I'll merge this PR.

[rosen-vladimirov]

@lambourn thanks a lot for your Contribution! We've merged the suggested fix and it will be included in our 5.0.0 release. The fix will be available soon in CLI's next version - you can install it by executing npm i -g nativescript@next (it may take 15-20 minutes to publish the next version with the fix).

[facetious]

Even though this does fetch the URL for the registry, this does not properly use the authentication specified in .npmrc. It is unclear to me why nativescript is rewriting npm in the first place, but I insist that the ability to authenticate needs to be present here.