Start/stop/status on multiple Neo4j instances

neo4js.js

/**
 * Start, stop or get the status of all Neo4j installations in current folder.
 * 
 * Usage:
 *   >node neo4js status
 *   >node neo4js start
 *   >node neo4js stop
 * Author: David Rapin 
 * Date: 2015-11-26.
 * licence: MIT
 */
'use strict';

var fs = require('fs');
var path = require('path');
var child = require('child_process');

// main

var command = process.argv.length === 2  ? 'status' : process.argv[2];
getNeo4jCommand('./', command, function(err, states) {
  if (err) {
    return console.log(err);
  }

  var maxLen = 0;
  states.forEach(function(state) {
    maxLen = Math.max(maxLen, state.folder.length);
  });

  states.forEach(function(state) {
    console.log(pad(state.folder, maxLen) + ': ' + state.value);
  });
});

// private functions follow

function getNeo4jCommand(base, option, cb) {
  var root = path.resolve(base);

  fs.readdir(root, function (err, folders) {
    if (err) { return cb(err); }
    var expectedResults = folders.length;
    var results = [];

    folders.forEach(function(folder) {
      var folderPath = path.resolve(root, folder);

      fs.stat(folderPath, function (err, stat) {
        if (err) { return cb(err); }

        if (!stat.isDirectory()) {
          // not a folder
          expectedResults--;
          return;
        }

        fs.readdir(folderPath, function (err, subFiles) {
          if (!containsAll(subFiles, ['bin', 'conf', 'data', 'lib', 'plugins', 'system'])) {
            // not a neo4j folder
            expectedResults--;
            return;
          }

          var command = path.resolve(folderPath, 'bin');
          child.exec('./neo4j ' + option, {cwd: command}, function (err, stdout, stderr) {

            // keeping only last line of output
            var outlines = stdout.trim().split('\n');
            var state = outlines[outlines.length - 1];

            results.push({folder:folder, value:state});

            // we are done collecting all results
            if (results.length === expectedResults) {

              // sort results by folder name
              results.sort(function(r1, r2) {
                return r1.folder.localeCompare(r2.folder);
              });

              cb(null, results);
            }
          });
        });
      });
    });
  });
}

function containsAll(checked, references) {
  var ok = true;
  references.forEach(function(reference) {
    if (checked.indexOf(reference) < 0) {
      ok = false;
    }
  });
  return ok;
}

function pad(str, len) {
  while (str.length < len) { str += ' '; }
  return str;
}