[NFR] Phalcon\DI: Info on whether DI service has been resolved

[temuri416]

In Phalcon\DI: add an attribute (and getter method) to indicate whether a service has been resolved.

I have my DI container with custom service in it:

$di = new Phalcon\Di;
$di->set('whatever', function(){
    return new Whatever();
}, true); // It is shared.

Shared service "whatever" may or may not be resolved (instantiated/set) by my application.

At the end of request cycle I need to know whether it was resolved or not.

Obviously, I don't want to do:

$di->get('whatever');

because that will resolve it for sure.

I need a way of knowing whether shared service "whatever" has been resolved or not.

Thanks,
Temuri

[ghost]

The quick fix is to override Whatever::resolve() method — it will be called when DI tries to resolve the service. You can add a static variable into Whatever and set it to true when resolve() is called.

[temuri416]

@sjinks Thanks for the tip. Is there a plan to implement it on DI level?

[ghost]

@phalcon What do you think?

[phalcon]

@temuri416 why do you need to do this?

[temuri416]

@phalcon

Here's what I'm doing in my project.

1. I have multiple file-based log devices that register groups of application events (auth, exceptions, model operations and so on). They are registered in DI, they are all separate entities and I do not want put wrappers around them.
2. Each log device has a fixed name in DI (LOGD_AUTH, LOGD_MODEL, etc).
3. I am using Transactions in my log devices.
4. At the end of execution cycle I am looping over known log device names and running ->commit() to flush log buffer.

The problem is that I do not know whether certain log devices have been used at all (LOGD_AUTH, for example, is only used once per user session).

I do not want to run into overhead of resolving log devices in DI that may have not been used.

(On a side note - there's another related problem - I need to know whether a log device has initiated a transaction - see #1238).

I have implemented a temporary workaround. But in my opinion, this belongs to system level.

[temuri416]

@phalcon

Can you please update me - is this categorized as "won't fix" ?

Thanks!

[phalcon]

#1238 is merged on 1.3.0

I'm keeping this open, if anyone wants to implement this

[ghost]

See #1319

$di = new \Phalcon\Di();
$di->set('resolved', function() { return new Whatever(); });
$di->set('notresolved', function() { return new Whatever(); });

$this->assertFalse($di->getService('resolved')->isResolved());
$this->assertFalse($di->getService('notresolved')->isResolved());

$di->get('resolved');

$this->assertTrue($di->getService('resolved')->isResolved());
$this->assertFalse($di->getService('notresolved')->isResolved());

[phalcon]

This is implemented in 1.3.0