johnny-dependency/lib/get-dependencies.js

npm -ls for remote packages

const pacote = require('pacote');

const rxjs = require('rxjs');
const npa = require('npm-package-arg');
const { getPackageMeta } = require('./util');

function flattenDependencies(deps) {
  return Object.keys(deps).reduce((acc, name) => {
    const version = deps[name];

    return acc.concat({ name, version });
  }, []);
}

function validateDeps(packages) {
  return packages.filter(npmPackage => {
    const type = npa(`${npmPackage.name}@${npmPackage.version}`).type;

    return type === 'tag' || type === 'version' || type === 'range';
  });
}

function getDependencies(thePackage, pacoteOptions = {}) {
  const resolvedDependencies = {};

  function getPackage(npmPackage) {
    const spec = `${npmPackage.name}@${npmPackage.version}`;

    return pacote.manifest(spec, pacoteOptions);
  }

  function getDirectDependencies(npmPackage, manifest) {
    const key = `${npmPackage.name}@${npmPackage.version}`;

    if (!(key in resolvedDependencies)) {
      resolvedDependencies[key] = manifest.version;

      const dependencies = validateDeps(flattenDependencies(manifest.dependencies));

      return rxjs.Observable.merge(rxjs.Observable.of(getPackageMeta(npmPackage, manifest)), rxjs.Observable.from(dependencies).mergeMap(dependency => getPackage(dependency).then(depManifest => ({ dependency, depManifest }))).mergeMap(({ dependency, depManifest }) => getDirectDependencies(dependency, depManifest)));
    }
    return rxjs.Observable.empty();
  }

  function getAllDependencies(npmPackage) {
    return new Promise(resolve => {
      getPackage(npmPackage).then(manifest => {
        getDirectDependencies(npmPackage, manifest).reduce((acc, curr) => acc.concat(curr), []).subscribe(dependencies => {
          resolve({ dependencies, resolvedDependencies });
        });
      });
    });
  }

  return getAllDependencies(thePackage);
}

module.exports = getDependencies;