SlingHttpServletRequest request is null in slingmodel

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DPrakashRaj

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DPrakashRaj

DPrakashRaj

12-08-2019

i want to adapt to sling model from another sling model. While doing so the SlingHttpServletRequest request is always null in second sling model. i tried with @Inject, @self and @@SlingObject. I am able to get request in FirstModel but not in SecondModel, i believe this happens because SecondModel is getting adapted with resource. Had anyone faced this issue and  how it worked..

Thanks in advance

basically my code is simlilar to:

@Model(

        adaptables =  {SlingHttpServletRequest.class, Resource.class},

        defaultInjectionStrategy = DefaultInjectionStrategy.OPTIONAL

)

public class SecondModel {

     @Inject

     private SlingHttpServletRequest request;

}

@Model(

        adaptables =  SlingHttpServletRequest.class,

        resourceType = "mycomponent path",

        defaultInjectionStrategy = DefaultInjectionStrategy.OPTIONAL

)

public class FirstModel {

@Inject

private SlingHttpServletRequest request;

@PostConstruct

    public void initResource() {

          SecondModel  obj  =  request.getResourceResolver().getResource(resourcePath).adaptTo(SecondModel .class)

     }

}

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Jörg_Hoh

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Jörg_Hoh

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Jörg_Hoh
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13-08-2019

The problem is that the SlingModel AdapterFactory cannot do the adaption properly, because it does not know about the details of FirstModel to inject the request into the SecondModel.

Either you adapt the request directly to SecondModel or you write a custom AdapterFactory which can the proper adaption from FirstModel to SecondModel. This is indepdent of the AEM version you use.

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Arun_Patidar

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Arun_Patidar
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13-08-2019

you can try with the approach suggested by @Jörg Hoh

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DPrakashRaj

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DPrakashRaj

DPrakashRaj

13-08-2019

Yes, request is available in FirstModel and also adaptTo() works. My problem is that i have

@SlingObject

    private SlingHttpServletRequest request;

also in SecondModel. This secondModel class uses request object to get requestURl from request and italways remains null. So, if i have above requirement then how can in inject request in SecondModel

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Arun_Patidar

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Arun_Patidar

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Arun_Patidar
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13-08-2019

Hi I tried the example whicj I shared with you earlier it works for me.

Performing Sling Model Adaptation Using Request and Resource Objects

@Model(adaptables = {SlingHttpServletRequest.class, Resource.class}, defaultInjectionStrategy = DefaultInjectionStrategy.OPTIONAL)

public class FirstModel {

@SlingObject

    private SlingHttpServletRequest request;

@PostConstruct

    public void initResource() {

          SecondModel  obj  =  request.getResourceResolver().getResource(resourcePath).adaptTo(SecondModel .class)

     }

}

With this approach request object should be available in FirstModel but not in SecondModel.

You should check the imports if doesn't work.

But if resource.getResourceResolver().getResource(resourcePath).adaptTo(SecondModel .class) works, you can use it.

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DPrakashRaj

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DPrakashRaj

DPrakashRaj

13-08-2019

resource.getResourceResolver().getResource(resourcePath).adaptTo(SecondModel .class) works but request object in FirstModel always remain null.

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Arun_Patidar

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Arun_Patidar

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Arun_Patidar
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13-08-2019

If it doesn't work, you can get resource using resource itself.

@Model(adaptables = Resource.class, defaultInjectionStrategy = DefaultInjectionStrategy.OPTIONAL)

public class SecondModel {

@Self

Resource resource;

@PostConstruct

    public void initResource() {

          SecondModel  obj  =  resource.getResourceResolver().getResource(resourcePath).adaptTo(SecondModel .class)

     }

}

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DPrakashRaj

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DPrakashRaj

DPrakashRaj

13-08-2019

i tried this code but it's not working, possible because i am using 6.3.2.0 and the example is for aem 6.4. Not sure if this is the reason

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Arun_Patidar

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Arun_Patidar
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13-08-2019

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Himanshu_Singhal

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Himanshu_Singhal

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Himanshu_Singhal
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13-08-2019

adapTo() only accept adapting class name. If you need to adapt to request, the link I shared in 1st reply describes how can you create custom adaptorfactory to adapt to request instead of resource.

https://taradevko.com/aem/sling-model-request-parameter-injector/

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DPrakashRaj

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DPrakashRaj

DPrakashRaj

13-08-2019

Not Sure if adapTo() accept any parameter other than class name. if you have any reference doc that will be helpful

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Himanshu_Singhal

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Himanshu_Singhal

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Himanshu_Singhal
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13-08-2019

In that case, one way is instantiating the model class by creating object and passing request (via constructor or setter). That's the traditional Java way of handling things.

Otherwise, you'll have to write custom AdaptorFactory.

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DPrakashRaj

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DPrakashRaj

DPrakashRaj

13-08-2019

Just for an update i am using aem 6.3.2.0

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DPrakashRaj

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DPrakashRaj

DPrakashRaj

13-08-2019

it's not failing but request comes out to be null and my requirement is to get complete Url of the page in sling model class

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DPrakashRaj

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DPrakashRaj

DPrakashRaj

13-08-2019

already tried and still request is null

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DPrakashRaj

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DPrakashRaj

DPrakashRaj

13-08-2019

With request.adaptTo() throws error with complaining unable to bind the injected value

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Arun_Patidar

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Arun_Patidar

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Arun_Patidar
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13-08-2019

Please inject using SlingObject annotation.

@SlingObject

    private SlingHttpServletRequest request;

Injects commonly used sling objects if the field matches with the class: request, response, resource resolver, current resource, SlingScriptHelper

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Jörg_Hoh

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Jörg_Hoh
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12-08-2019

Hi,

can you show the code you are using to adapt FirstModel to SecondModel? My impression is that the (default) AdapterFactory which is behind these adaptions for the SlingModel cannot handle that case, but because the Request injection is marked as optional, it does not fail.

If you want to handle that case of adapting FirstModel to SecondModel, it's probably best to write a custom AdapterFactory.

Jörg

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Himanshu_Singhal

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Himanshu_Singhal

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Himanshu_Singhal
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12-08-2019

You may try to adaptTo() another Model with request instead of resource and check it that works. Never tried adapting with request but it's just a thought.

https://taradevko.com/aem/sling-model-request-parameter-injector/  - This article might help as fits your scenario.