How to use the strapi-utils.logger.error function in strapi-utils

strapi.start({}, err => {

    // Log and exit the REPL in case there is an error
    // while we were trying to start the server.
    if (err) {
      logger.error('Could not load the Strapi framework.');
      logger.error('Are you using the latest stable version?');
      process.exit(1);
    }

    // Open the Node.js REPL.
    const repl = REPL.start(strapi.config.name + ' > ' || 'strapi > ');
    repl.on('exit', err => {

      // Log and exit the REPL in case there is an error
      // while we were trying to open the REPL.
      if (err) {
        logger.error(err);
        process.exit(1);
      }

      process.exit(0);

let invalidPackageJSON;

    try {
      require(pathToPackageJSON);
    } catch (e) {
      invalidPackageJSON = true;
    }

    if (invalidPackageJSON) {
      return logger.error('This command can only be used inside a Strapi project.');
    }
  }

  // Show usage if no generator type is defined.
  if (!scope.generatorType) {
    return logger.error('Write `$ strapi generate:something` instead.');
  }

  // Return the scope and the response (`error` or `success`).
  return generate(scope, {

    // Log and exit the REPL in case there is an error
    // while we were trying to generate the requested generator.
    error: function returnError(msg) {
      logger.error(msg);
      process.exit(1);
    },

    // Log and exit the REPL in case of success
    // but first make sure we have all the info we need.
    success: function returnSuccess() {
      if (!scope.outputPath && scope.filename && scope.destDir) {

const scope = {
    rootPath: process.cwd(),
    strapiRoot: path.resolve(__dirname, '..'),
    id: id,
    args: cliArguments,
    strapiPackageJSON: packageJSON
  };

  // Register the generator type.
  // It can be a controller, model, service, etc.
  scope.generatorType = process.argv[2].split(':')[1];

  // Check that we're in a valid Strapi project.
  if (scope.generatorType !== 'new' || scope.generatorType !== 'generator' || scope.generatorType !== 'hook') {
    if (!cli.isStrapiApp()) {
      return logger.error('This command can only be used inside a Strapi project.');
    }
  }

  // Show usage if no generator type is defined.
  if (!scope.generatorType) {
    return logger.error('Write `$ strapi generate:something` instead.');
  }

  // Return the scope and the response (`error` or `success`).
  return generate(scope, {

    // Log and exit the REPL in case there is an error
    // while we were trying to generate the requested generator.
    error: function returnError(msg) {
      logger.error(msg);
      process.exit(1);

module.exports = function (plugin) {
  // Define variables.
  const pluginPath = `./plugins/${plugin}`;

  // Check that we're in a valid Strapi project.
  if (!cli.isStrapiApp()) {
    return logger.error('This command can only be used inside a Strapi project.');
  }

  // Check that the plugin is installed.
  if (!fs.existsSync(pluginPath)) {
    logger.error(`It looks like this plugin is not installed. Please check that \`${pluginPath}\` folder exists.`);
    process.exit(1);
  }

  // Delete the plugin folder.
  rimraf(pluginPath, (err) => {
    if (err) {
      logger.error('An error occurred during plugin uninstallation.');
      process.exit(1);
    }

    // Success.
    logger.info('The plugin has been successfully uninstalled.');
    process.exit(0);
  });
};

// Register the name.
  scope.generatorName = cliArguments[1];

  // Check that we're in a valid Strapi project.
  if (scope.generatorType !== 'new' || scope.generatorType !== 'generator' || scope.generatorType !== 'hook') {
    const pathToPackageJSON = path.resolve(scope.rootPath, 'package.json');
    let invalidPackageJSON;

    try {
      require(pathToPackageJSON);
    } catch (e) {
      invalidPackageJSON = true;
    }

    if (invalidPackageJSON) {
      return logger.error('This command can only be used inside a Strapi project.');
    }
  }

  // Show usage if no generator type is defined.
  if (!scope.generatorType) {
    return logger.error('Write `$ strapi generate:something` instead.');
  }

  // Return the scope and the response (`error` or `success`).
  return generate(scope, {

    // Log and exit the REPL in case there is an error
    // while we were trying to generate the requested generator.
    error: function returnError(msg) {
      logger.error(msg);
      process.exit(1);

}, null, '\t'), function (err) {
          if (err) {
            logger.error('Impossible to write the `.strapirc` file at `' + HOME + '`');
            logger.error('Please check read/write permissions before execute `$ strapi config`');
            logger.error('You can manually create the file at `' + HOME + '`');
          } else {
            logger.info('Global configuration file successfully created at `' + HOME + '`');
            logger.info('Please read http://strapi.io/documentation/customization to learn more');
          }
          process.exit(1);
        });
      } else if (err.code === 'EACCES') {

fs.access(path.resolve(HOME, '.strapirc'), fs.F_OK | fs.R_OK | fs.W_OK, function (err) {
    if (err) {
      if (err.code === 'ENOENT') {
        logger.error('No `.strapirc` file detected at `' + HOME + '`.');
        logger.error('Execute `$ strapi config` to create one.');
      } else if (err.code === 'EACCES') {
        logger.error('Impossible to access the `.strapirc` file at `' + HOME + '`.');
        logger.error('Please check read/write permissions before execute `$ strapi update`.');
      }
      process.exit(1);
    } else {
      const config = JSON.parse(fs.readFileSync(path.resolve(HOME, '.strapirc')));
      _.forEach(config.generators, function (info, name) {
        try {
          process.chdir(path.resolve(__dirname, '..', 'node_modules', 'strapi-generate-' + name));
          logger.debug('Pulling the latest updates of `strapi-generate-' + name + '`.');
          exec('git pull ' + info.remote + ' ' + info.branch, function (err) {
            if (err) {
              logger.error('Impossible to update `strapi-generate-' + name + '`.');
            } else {
              logger.info('Successfully updated `strapi-generate-' + name + '`.');

}, null, '\t'), function (err) {
          if (err) {
            logger.error('Impossible to write the `.strapirc` file at `' + HOME + '`');
            logger.error('Please check read/write permissions before execute `$ strapi config`');
            logger.error('You can manually create the file at `' + HOME + '`');
          } else {
            logger.info('Global configuration file successfully created at `' + HOME + '`');
            logger.info('Please read http://strapi.io/documentation/customization to learn more');
          }
          process.exit(1);
        });
      } else if (err.code === 'EACCES') {

fs.access(path.resolve(HOME, '.strapirc'), fs.F_OK | fs.R_OK | fs.W_OK, function (err) {
    if (err) {
      if (err.code === 'ENOENT') {
        logger.error('No `.strapirc` file detected at `' + HOME + '`.');
        logger.error('Execute `$ strapi config` to create one.');
      } else if (err.code === 'EACCES') {
        logger.error('Impossible to access the `.strapirc` file at `' + HOME + '`.');
        logger.error('Please check read/write permissions before execute `$ strapi update`.');
      }
      process.exit(1);
    } else {
      const config = JSON.parse(fs.readFileSync(path.resolve(HOME, '.strapirc')));
      _.forEach(config.generators, function (info, name) {
        try {
          process.chdir(path.resolve(__dirname, '..', 'node_modules', 'strapi-generate-' + name));
          logger.debug('Pulling the latest updates of `strapi-generate-' + name + '`.');
          exec('git pull ' + info.remote + ' ' + info.branch, function (err) {
            if (err) {
              logger.error('Impossible to update `strapi-generate-' + name + '`.');
            } else {
              logger.info('Successfully updated `strapi-generate-' + name + '`.');
            }
          });

error: function returnError(err) {
      logger.error(err);
      process.exit(1);
    },