Hooks inside hooks possible?

[Gadgetto]

Hi guys (didn't see any gals here),

I have a module which has some custom helper classes. One of these classes has methods which are hookable. The class is derived from WireData. An additional complication is that this class has its own namespace. What would be the correct way to provide the hookable methods via API?

Here is a very simplified code sample of the class:

<?php
namespace SnipWire\Services;

use ProcessWire\WireData;
use ProcessWire\WireException;

class Webhooks extends WireData {

    ...

    public function ___handleOrderCompleted() {
        if ($this->debug) $this->wire('log')->save(
            self::snipWireWebhooksLogName,
            '[DEBUG] Webhooks request: handleOrderCompleted'
        );
        $this->responseStatus = 202; // Accepted
    }

    public function ___handleOrderStatusChanged() {
        if ($this->debug) $this->wire('log')->save(
            self::snipWireWebhooksLogName,
            '[DEBUG] Webhooks request: handleOrderStatusChanged'
        );
        $this->responseStatus = 202; // Accepted
    }

    ...
}

The class itself is invoked/used by a hook from within the main module:

Depending of the event, one of the methods of the Webhooks class above is triggered. A developer should now be able to use one of the ___handle* methods to do further things.

    /**
     * Check for webohook request and process them.
     * (Method triggered before ProcessPageView::execute)
     *
     */
    public function checkWebhookRequest(HookEvent $event) {
        if ($webhooksEndpoint = $this->get('webhooks_endpoint')) {
            if ($this->sanitizer->url($this->input->url) == $webhooksEndpoint) {
                /** @var Webhooks $webhooks Custom ProcessWire API variable */
                $this->wire('webhooks', new Webhooks());
                $this->wire('webhooks')->process();
                $event->replace = true;
                // @note: Tracy Debug won't work from here on as normal page rendering is omitted!
            }
        }
    }

Should I provide a custom API variable e.g. $webhooks? Or how is the best way to do this?

Edited March 18, 2020 by Gadgetto
Changed post title

[Zeka]

Why just not implement a module? 

[Gadgetto]

On 3/11/2020 at 8:24 AM, Zeka said:

Why just not implement a module? 

What would be the benefit of making a custom helper class a module?

[bernhard]

Hey @Gadgetto did you find a solution for your problem?

On 3/10/2020 at 6:21 PM, Gadgetto said:

$this->wire('webhooks')->process();

What does that do?

I'm still not sure I understand the problem completely and the best solution in more complex setup always depends on the situation, but maybe you could make a proxy method in your main module that is hookable instead of making all methods in the helper module hookable? Some untested pseudo-code:

// main module SnipWire
public function webhooks(...$args) {
	$helper = $this->get('webhooks_endpoint')
	if($args['foo']) return $helper->foo(...$args); // returns "foo"
	if($args['bar']) return $helper->bar(...$args); // returns "bar"
	...
}


// site/ready.php
$wire->addHookAfter("SnipWire::webhooks", function($event) {
	$name = $event->arguments('name');
	if($name != "foo") return;
	$event->return .= " hooked";
}

// then the foo webhook should return "foo hooked" instead of "foo"

 

[Gadgetto]

Hi @bernhard, thanks for jumping in!

14 hours ago, bernhard said:

On 3/10/2020 at 6:21 PM, Gadgetto said:

$this->wire('webhooks')->process();

What does that do?

The Webhooks class handles Snipcart's web hook events and provides hookable methods to attach custom code to those events. eg. orderCompleted, customerUpdated, ad so on ... A Snipcart webhook event is a POST request which is sent to your site by Snipcart. Each POST request holds json encoded data corresponding to the specific situation. e.g. A orderCompleted event POSTs the full order array to your site.

The Webhooks class is available as custom API variable $webhooks.

This code in SnipWire main module takes over POST request from Snipcart:

    /**
     * Check for webohook request and process them.
     * (Method triggered before ProcessPageView execute)
     *
     */
    public function checkWebhookRequest(HookEvent $event) {
        if ($webhooksEndpoint = $this->get('webhooks_endpoint')) {
            if ($this->sanitizer->url($this->input->url) == $webhooksEndpoint) {
                $this->wire('webhooks')->process();
                $event->replace = true;
                // @note: Tracy Debug won't work from here on as normal page rendering is omitted!
            }
        }
    }

This line...

$this->wire('webhooks')->process();

... starts the process which handles a Snipcart POST request:

https://github.com/gadgetto/SnipWire/blob/cc9922fbe059b3961d3ee63be253e34d4cf96bc1/services/Webhooks.php#L108

Within this processing the specific hookable method within the Webhooks class is called. I thought it should be easy to provide those methods a hookable. But it seems this isn't so easy with custom classes.

For example - this doesn't work:

$webhooks->addHook('handleOrderCompleted', function($event) {
	wire('log')->save('webhookstest', 'hook works');
}); 

and also not this:

$webhooks->addHook('Webhooks::handleOrderCompleted', function($event) {
	wire('log')->save('webhookstest', 'hook works');
}); 

or this:

$wire->addHook('Webhooks::handleOrderCompleted', function($event) {
	wire('log')->save('webhookstest', 'hook works');
}); 

 

[bernhard]

Just tried and it works just as you expected it to work:

That's why I was asking what the process() does exactly (code!).

<?php namespace RockSearch;
use ProcessWire\Wire;
class Matcher extends Wire {
  public function ___foo() {
    return 'foo';
  }

 

[Gadgetto]

12 minutes ago, bernhard said:

Just tried and it works just as you expected it to work:

This is strange! Why doesn't it work in my environment? None of the hooks I posted above is triggered.

[bernhard]

class Webhooks extends WireData {

I guess WireData does not support hooks whereas Wire does.

[Gadgetto]

1 hour ago, bernhard said:

class Webhooks extends WireData {

I guess WireData does not support hooks whereas Wire does.

From PW docs:

Quote

To make a class capable of having hookable methods, simply extend one of ProcessWire's classes such as Wire or WireData as your base

So it should work. ?

[bernhard]

Of course it does, as WireData extends Wire, sorry for that ?‍♂️

Does it work if you call $this->handleOrderCompleted() directly? Maybe the dynamic method call is the problem (wouldn't know why, though). Maybe it is working, but you just think it is not. How do you check if it is working? ? 

[Gadgetto]

1 hour ago, bernhard said:

Of course it does, as WireData extends Wire, sorry for that ?‍♂️

Does it work if you call $this->handleOrderCompleted() directly? Maybe the dynamic method call is the problem (wouldn't know why, though). Maybe it is working, but you just think it is not. How do you check if it is working? ? 

I have this part in my ready.php

$webhooks->addHook('handleOrderCompleted', function($event) {
	wire('log')->save('webhookstest', 'hook works');
}); 

But the log entry isn't written.

[Gadgetto]

OK, If I call this manually in Tracy Console:

$webhooks->handleOrderCompleted();

The hook is triggered!

Shouldn't a dynamic method call trigger a hook event?

$this->{$methodName}();

 

[Gadgetto]

Could be a bug in PW...

[bernhard]

34 minutes ago, Gadgetto said:

I have this part in my ready.php

$webhooks->addHook('handleOrderCompleted', function($event) {
	wire('log')->save('webhookstest', 'hook works');
}); 

13 minutes ago, Gadgetto said:

Could be a bug in PW...

No, it is a bug in your hook ?  You are adding a new method with your hook, not hooking into that method! You are simply missing the addHookAFTER

$webhooks->addHookAfter('handleOrderCompleted', function($event) {
	wire('log')->save('webhookstest', 'hook works');
}); 

 

[Gadgetto]

44 minutes ago, bernhard said:

No, it is a bug in your hook ?  You are adding a new method with your hook, not hooking into that method! You are simply missing the addHookAFTER

$webhooks->addHookAfter('handleOrderCompleted', function($event) {
	wire('log')->save('webhookstest', 'hook works');
}); 

 

I changed to addHookAfter but still doesn't work. (had this tried before without success) ?

[Gadgetto]

Are you sure? Maybe I don't understand this correctly... It seems a new method is only added if the specified method name doesn't exist.

From the docs:

---

You can add new methods to any ProcessWire class in the same way that you would hook an existing method. The only difference is that the method doesn't already exist, so you are adding it. Also, because there is no distinction of "before" or "after" for something that doesn't already exist, you can attach the method using addHook(); rather than addHookBefore(); or addHookAfter() … though technically it doesn't really matter what you use here. Lets say that you wanted to add a new method to all Page instances that outputs a relative time string of when the page was last modified (for example, "45 minutes ago" or "3 days ago", etc.):

public function init() {
  $this->addHook('Page::lastModified', $this, 'lastModified');
}

public function lastModified($event) {
  $page = $event->object;
  $event->return = wireRelativeTimeStr($page->modified);
}

Hooking both before and after
If you want your hook method to run both before and after a particular event occurs, you can specify that in an $options array to the addHook() call, like this:

$wire->addHook('Class::method', function(HookEvent $e) {
  // ...
}, [ 'before' => true, 'after' => true ]); 

[bernhard]

You are right, I was wrong, sorry again ? 

Well, so I'd try changing the dynamic method call to a static one and see if the hook get's triggered. If yes, you know where the problem lies...

[Gadgetto]

Changed to a static method call - still not working... ?

I'm just thinking it could be a problem that the process() method (which calls the hook method dynamically) itself is also triggered by a hook?

public function init() {
    ...
    $this->addHookBefore('ProcessPageView::execute', $this, 'checkWebhookRequest');
    ...
}

/**
 * Check for webohook request and process them.
 * (Method triggered before ProcessPageView execute)
 *
 */
public function checkWebhookRequest(HookEvent $event) {
    if ($webhooksEndpoint = $this->get('webhooks_endpoint')) {
        if ($this->sanitizer->url($this->input->url) == $webhooksEndpoint) {
            $this->wire('webhooks')->process();
            $event->replace = true;
            // @note: Tracy Debug won't work from here on as normal page rendering is omitted!
        }
    }
}

 

[bernhard]

Yes, that sounds reasonable!

[Gadgetto]

18 hours ago, bernhard said:

Yes, that sounds reasonable!

If this is the real reason, I don't know how to solve this, as process() needs to be called by a hook. ?

[Gadgetto]

Quote

it could be a problem that the process() method (which calls the hook method dynamically) itself is also triggered by a hook

Could this be a bug in PW or is it intentional? Should I file an issue?

Any ideas from the other pros here? I'm really stuck with this. ? 

[bernhard]

Just now, Gadgetto said:

Could this be a bug in PW or is it intentional? Should I file an issue?

I'd first confirm that this is really the problem by putting together a test-setup that makes the issue reproducable. It is definitely possible to add hooks inside hooks, but timing is very important! https://processwire.com/blog/posts/new-ajax-driven-inputs-conditional-hooks-template-family-settings-and-more/#new-conditional-hooks

So I think it's more likely a problem in your code than a bug in PW... 

[Gadgetto]

59 minutes ago, bernhard said:

I'd first confirm that this is really the problem by putting together a test-setup that makes the issue reproducable. It is definitely possible to add hooks inside hooks, but timing is very important! https://processwire.com/blog/posts/new-ajax-driven-inputs-conditional-hooks-template-family-settings-and-more/#new-conditional-hooks

So I think it's more likely a problem in your code than a bug in PW... 

I'll try to write a small test case. Thanks again @bernhard!

[Gadgetto]

I have written a small test module which simulates the required situation. Unfortunately the hook mentioned above does not work here either.

I think I'll file an issue on GitHub.

Here is a ZIP with the module files:

HookTest.zip

[bernhard]

That's strange. I've just realized that I did exactly the same in one of my modules and prepared methods to be hookable (just in case I'd need it one day) and those hooks do also not get triggered. The strange thing is that this little module works just as expected:

<?php namespace ProcessWire;
class RockHook extends WireData implements Module {

  public static function getModuleInfo() {
    return [
      'title' => 'RockHook',
      'version' => '0.0.1',
      'summary' => 'RockHook',
      'autoload' => true,
      'icon' => 'bolt',
      'requires' => [],
      'installs' => [],
    ];
  }

  public function init() {
    $this->addHookAfter("ProcessPageView::execute", function(HookEvent $event) {
      $this->hello("trigger hello() in execute() hook");
    });
    $this->addHookAfter('hello', function(HookEvent $event) {
      bd('hello hooked in RockHook::init()');
    });
  }

  public function ___hello($where) {
    bd('hello!', $where);
  }
}

// in site/ready.php
$this->addHookAfter('RockHook::hello', function(HookEvent $event) {
  bd('hello hooked in /site/ready.php');
});

Edit: Attaching the hook like this does also work:

<?php namespace ProcessWire;
class RockHook extends WireData implements Module {

  public static function getModuleInfo() {
    return [
      'title' => 'RockHook',
      'version' => '0.0.1',
      'summary' => 'RockHook',
      'autoload' => true,
      'singular' => false,
      'icon' => 'bolt',
      'requires' => [],
      'installs' => [],
    ];
  }

  public function init() {
    $this->addHookAfter("ProcessPageView::execute", $this, "handleWebhook");
    $this->addHookAfter('hello', function(HookEvent $event) {
      bd('hello hooked in RockHook::init()');
    });
  }

  public function handleWebhook($event) {
    $this->hello("trigger hello() in execute() hook");
  }

  public function ___hello($where) {
    bd('hello!', $where);
  }
}