#Controllers
Sails controllers work very similarly to controllers in other MVC frameworks. Think of controllers as the middlemen between your models and your views.
Controllers are defined in the /api/controllers/ folder. By default when you create a controller using the command line, you can add additional arguments that represent the controller actions.
sails generate controller comment create destroy tag like
generates:
// Comment controller with generated actions.
var CommentController = {
create: function(req, res) {
},
destroy: function(req, res) {
},
tag: function(req, res) {
},
like: function(req, res) {
}
}
module.exports = CommentController;Whether it was sent as POSTed JSON, to look up the value of a request parameter, do:
var foo = req.param('foo');If you need to dive deeper into request parameters, check out the express guide.
Whether or not this request was sent over Socket.io
Whether or not this is an AJAX/xhr request
Whether or not this request is JSONish (has a JSON "Accept" or "Content-Type" header)
When responding to a request, Sails uses many of the same res methods as Express.
This method is an enhanced version of Express's res.render(). The method res.view() automatically renders the appropriate view based on the controller and action. The original function is still accessible via res.render().
From the express guide. The res.send() method is a high level response utility allowing you to pass objects to respond with json, strings for html, Buffer instances, or numbers representing the status code. The following are all valid uses:
res.send(); // 204
res.send(new Buffer('wahoo'));
res.send({ some: 'json' });
res.send('<p>some html</p>');
res.send('Sorry, cant find that', 404);
res.send('text', { 'Content-Type': 'text/plain' }, 201);
res.send(404);By default the Content-Type response header is set, however if explicitly assigned through res.send() or previously with res.header() or res.contentType() it will not be set again.
Note that this method ends the response, so you will want to use node’s res.write() for multiple writes or streaming.
From the express guide. Send a JSON response with optional headers and status. This method is ideal for JSON-only APIs, however res.send(obj) will send JSON as well, though not ideal for cases when you want to send for example a string as JSON, since the default for res.send(string) is text/html.
res.json(null);
res.json({ user: 'tj' });
res.json('oh noes!', 500);
res.json('I dont have that', 404);From the express guide. Redirect to the given url with a default response status of 302.
res.redirect('/', 301);
res.redirect('/account');
res.redirect('http://google.com');
res.redirect('home');
res.redirect('back');Whether or not the view for this controller exists.
In many cases, the reason you have a controller at all is that you want to do custom stuff with your models. Otherwise, you could just use the defaults!
For example, your controller might look like:
// Keep in mind you'd probably want to do this transactionally, in case the chicken is being pecked
var ChickenController = {
// Peck the chicken specified by id (subtract 50 HP)
peck: function (req,res) {
Chicken.find(req.param('id')).done(function (err,chicken) {
if (err) return res.send(err,500);
if (!chicken) return res.send("No other chicken with that id exists!", 404);
if (chicken.hp <= 0) return res.send("The other chicken is already dead!", 403);
// Subtract 50 HP from the chicken
chicken.hp -= 50;
// Persist the change
Chicken.update(chicken.id,chicken).done(function (err) {
if (err) return res.send(err,500);
// Report back with the new state of the chicken
res.json(chicken);
});
});
}
};
module.exports = ChickenController;Check out the page on Models to learn more.