bower-npm-resolver/dist/npm/cache.js

Use npm as a registry for your Bower Dependencies

/**
 * The MIT License (MIT)
 *
 * Copyright (c) 2016-2020 Mickael Jeanroy
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in all
 * copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 * SOFTWARE.
 */
'use strict';

var path = require('path');

var fs = require('fs');

var semver = require('semver');

var Q = require('q');

var requireg = require('requireg');

var npm = requireg('npm');

var npmLoad = require('./_load');

var npmConfig = require('./_config');

module.exports = function cache(args) {
  return cacheAdd(args).then(function (result) {
    return readCacheQueryResult(result);
  });
};
/**
 * Executes `npm cache-add` command with passed arguments.
 * Arguments is the name of the cache to download.
 * So if cmd command was `npm cache-add bower@1.7.7 versions`, then argument
 * would be `['bower@1.7.7', 'versions']`.
 *
 * The returned promise will be resolved with the result of the cache command (i.e
 * object with all informations about the package).
 *
 * @param {Array} pkg THe package to download.
 * @return {Promise} The promise object
 */


function cacheAdd(pkg) {
  return npmLoad().then(function (meta) {
    if (semver.lt(meta.version, '5.0.0')) {
      return npmCacheAddLegacy(pkg);
    } else {
      return npmCacheAdd(pkg);
    }
  });
}
/**
 * Run npm cache command and resolve the deferred object with the returned
 * metadata.
 *
 * @param {string} pkg NPM Package id (i.e `bower@1.8.0`).
 * @return {void}
 */


function npmCacheAddLegacy(pkg) {
  return Q.Promise(function (resolve, reject) {
    npm.commands.cache(['add', pkg], function (err, data) {
      if (err) {
        reject(err);
      } else {
        resolve({
          cache: npm.cache,
          name: data.name,
          version: data.version,
          path: path.resolve(npm.cache, data.name, data.version, 'package.tgz'),
          integrity: null
        });
      }
    });
  });
}
/**
 * Run npm cache command and resolve the deferred object with the returned
 * metadata.
 *
 * @param {string} pkg NPM Package id (i.e `bower@1.8.0`).
 * @return {void}
 */


function npmCacheAdd(pkg) {
  var promise = Q.promise(function (resolve, reject) {
    npm.commands.cache(['add', pkg], function (err, result) {
      if (err) {
        reject(err);
      } else {
        resolve(result);
      }
    });
  });
  return promise.then(function (info) {
    return info ? info : manifest(pkg);
  }).then(function (info) {
    return {
      cache: path.join(npm.cache, '_cacache'),
      name: info.manifest.name,
      version: info.manifest.version,
      integrity: info.integrity,
      path: null
    };
  });
}
/**
 * Fetch package manifest using `pacote` dependency.
 * With npm < 5.6.0, the manifest object was automatically returned by
 * the `cache.add` command. This function is here to deal with npm >= 5.6.0
 * to get the `integrity` checksum used to download the tarball using `cacache`.
 *
 * @param {string} pkg Package identifier.
 * @return {Promise<Object>} The manifest object.
 */


function manifest(pkg) {
  return require('pacote').manifest(pkg, npmConfig()).then(function (pkgJson) {
    return {
      integrity: pkgJson._integrity,
      manifest: {
        name: pkgJson.name,
        version: pkgJson.version
      }
    };
  });
}
/**
 * Read cache query result and transform cache entry result to a readable stream.
 *
 * @param {Object} result The cache query result.
 * @return {Object} The result.
 */


function readCacheQueryResult(result) {
  var name = result.name;
  var version = result.version;
  var inputStream = result.path ? createReadStream(result) : getStreamByDigest(result);
  return {
    name: name,
    version: version,
    inputStream: inputStream
  };
}
/**
 * Create stream from given `path` property of result object.
 *
 * @param {Object} result The result object.
 * @return {ReadStream} The result stream.
 */


function createReadStream(result) {
  return fs.createReadStream(result.path);
}
/**
 * Get stream from npm cache.
 *
 * @param {Object} result The result object.
 * @return {ReadStream} The result stream.
 */


function getStreamByDigest(result) {
  return require('cacache').get.stream.byDigest(result.cache, result.integrity);
}