If sails is already loaded, do not load again

[kmcgrath]

This allows sails-migrations to be used within sails itself. It checks to see if sails is already loaded. If so, it does not do it again.

Then it is possible use sails-migrations directly to report on status and currentVersion from a Controller.

In the following example I also have the ability to migrate and roll back, but I realize you may not want to do that here, unless bootstrapping an application through a web interface.

/** 
 * MigrateController
 *   
 * @description :: Server-side logic for managing knex migrations
 * @help        :: See http://sailsjs.org/#!/documentation/concepts/Controllers
 */  

var vm = require('vm');
var sailsMigrations = require('sails-migrations');

module.exports = { 

  latest: function(req,res,next) {
    return sailsMigrations.migrate()
    .spread(function (batchNo, log) {
      if (log.length === 0) {
        res.json({
          message: 'Already up to date'
        }); 
      }   
      else {
        res.json({
          message: 'Batch ' + batchNo + ' run: ' + log.length,
          migrations: log 
        }); 
      }   
    })  
    .catch(next);
  },  

  rollback: function(req,res,next) {
    return sailsMigrations.rollback()
    .spread(function (batchNo, log) {
      if (log.length === 0) {
        res.json({
          message: 'Already at the base migration'
        }); 
      }   
      else {
        res.json({
          message: 'Batch ' + batchNo + ' rolled back: ' + log.length,
          migrations: log 
        }); 
      }   
    })  
    .catch(next);
  },  

  currentVersion: function(req,res,next) {
    return sailsMigrations.currentVersion()
    .then(function (version) {
      res.json({
        version: version
      }); 
    })  
    .catch(next);
  },  

  status: function(req,res,next) {
    return sailsMigrations.status()
    .spread(function (all,completed) {
      all = all || []; 
      completed = completed || []; 

      res.json({
        all: all,
        completed: completed
      }); 
    })  
    .catch(next);
  }   

};  

[RWOverdijk]

@kmcgrath Are you sure that the options don't have to be set?

[RWOverdijk]

@mikermcneil Maybe you can advise me on this one :) It looks good to me, but you probably know better.

[kmcgrath]

@RWOverdijk options are set only if sails is not loaded, which still happens here. If sails has been loaded they should already have been set. Does that address your question?

[RWOverdijk]

@kmcgrath Almost! I just wonder if migrations perhaps needs some settings that the running instance perhaps doesn't have

[RWOverdijk]

@kmcgrath Is this PR still relevant to you?

[kmcgrath]

It is. We use this to provide an admin interface that can be used to see migration status as well as bootstrap new applications through a web interface/API.

[RWOverdijk]

To me this PR makes sense. I haven't tested it yet, so I should. Have you tested this with and without running it yourself? If so, could you perhaps tell me how you tested it? This lib needs more tests, I'm aware of that.

[kmcgrath]

We have a DevOps team running it in production for an internal application. I'm actually not on that project anymore but I help out when needed. I can try to get one of them on this PR, if needed.

[RWOverdijk]

@kmcgrath Seeing how this is a tool used in production by multiple people, I'd very much like that yes. Better safe than sorry. :)

[RWOverdijk]

@kmcgrath Would you mind rebasing this? I just merged the other PR, which conflicts with this one.

[kmcgrath]

Sorry for the multiple commits we had a branch with two already merged. I resolved then merged with that one.

It boils down to one condition statement that checks for sails.hooks. If that exists then it does not run sails.load because it is already loaded.