Get image in the context of a hook

[olafgleba]

Hi,

depending on the status of a set checkbox (set_create_vcard) i generate VCF files on page save (admin). For this i have a hook (s. below) placed in admin.php. Everything behaves like it should. But when i try to integrate a image in the vcard i get the following message/error on page save (Returned data is not a image comes from the exception class of the VCard lib).

ProcessPageEdit: Returned data is not an image.

I am asking this question here in the PW Forum (and not on the github board of the lib), because integrating the (essentially) similiar code in a regular template file (e.g. outside the hook) works flawlessly (with the same images accepted, e.g do not trigger any error). I am rather a newbie when it comes to hooks. So its likely that i miss something.

Any hints much appreciated,
Olaf

<?php

// file: admin.php

// get vcard lib (composer module) on top
use JeroenDesloovere\VCard\VCard;

/**
 * Admin template just loads the admin application controller, 
 * and admin is just an application built on top of ProcessWire. 
 *
 * This demonstrates how you can use ProcessWire as a front-end 
 * to another application. 
 *
 * Feel free to hook admin-specific functionality from this file, 
 * but remember to leave the require() statement below at the end.
 * 
 */

$wire->addHookBefore('Pages::saveReady', function($event){
  $page = $event->arguments(0);
  if($page->hasField("set_create_vcard")) {
    if($page->set_create_vcard == 1) {
      $page->set_create_vcard = 0;

      // define vcard
      $vcard = new VCard();

      // define variables
      $fullname = $page->combo_contact->name;

      // add personal data
      $vcard->addName($fullname);

      /* ... some other allocations ... */

      // WHERE IT BREAKS...
      if($page->image_contact) {
        $vcard->addPhoto($page->image_contact->filename);
      }

      $vcard->setSavePath($this->wire('config')->paths->root.'process/public/vcard');
      $vcard->save();

      $this->message('VCF Datei für den Kontakt wurde erstellt');

    }
  }
});

// Do not touch...
require($config->paths->adminTemplates . 'controller.php');

 

[horst]

I believe you are using a single images field, means the allowed amount of stored image is set to 1.

If that is true, the scope where you calling it is important. Behind the scenes a single image field and a multiple images field are the same, they only behave different in template scope, where output formatting is set to true by default. For single image fields this reduces the code a bit so that you already act with a single image right after the field name.

So in a function or method scope, this is not (cannot be) auto set to true, and your image field returns a collection from which you have to select the first item: 

$page->image_contact->first()

So a working code then can be: 

      if(0 < count($page->image_contact)) {
        $vcard->addPhoto($page->image_contact->first()->filename);
      }

 

[bernhard]

And if you want to make things a little more obvious to anybody reading your code (or simply to yourself) you can use getUnformatted() to return the array version of the field no matter what the current outputformatting is:

<?php
$images = $page->getUnformatted('imagesfield');
if($images->count()) {
  $img = $images->first();
  ...
}

 

[horst]

6 minutes ago, bernhard said:

getUnformatted()

Ha, that's what I use only and everywhere since a couple of years already. Because the code then is bulletproof, even if sometimes in the future a single image field need to be changed to a multiple one or vise versa. No changes in code are needed.
First I thought to mention that too, but decided that it may be not close enough to the topic. So good that you brought it up! ?

[Robin S]

1 hour ago, bernhard said:

And if you want to make things a little more obvious to anybody reading your code (or simply to yourself) you can use getUnformatted() to return the array version of the field no matter what the current outputformatting is

True, but just want to point out there can be occasional "gotchas" when doing this because PW sometimes returns things that may be unexpected in the unformatted value.

For example, the unformatted value of a Page Reference field will include unpublished pages and the unformatted value of a Repeater field can include "ready" items that are not populated in Page Edit.

And in the case being discussed here the unformatted value of an images field can include "temporary" images that have been uploaded in Page Edit but the page has not yet been saved. So in the example below the frog image is saved but the fish image has just been uploaded but not yet saved, and might yet be abandoned before saving because of being a mistake or unwanted. Yet it appears in the unformatted value:

[horst]

7 minutes ago, Robin S said:

And in the case being discussed here the unformatted value of an images field can include "temporary" images that have been uploaded in Page Edit but the page has not yet been saved. So in the example below the frog image is saved but the fish image has just been uploaded but not yet saved, and might yet be abandoned before saving because of being a mistake or unwanted. Yet it appears in the unformatted value:

Very interesting details, that I haven't known. So my use cases for getUnformatted("imagesField") is in template / frontend context only. I haven't had a need to use this in the admin, but definitely will note that down for when this use case may arise.

[Robin S]

6 minutes ago, horst said:

I haven't had a need to use this in the admin, but definitely will note that down for when this use case may arise.

It's not different between frontend and admin - I just used that in my screenshot to show the as-yet-unsaved image. So you do have to watch out for it in template code too. Suppose you have a busy site and you're using getUnformatted() in your template code. If a website editor accidentally uploads the wrong image (you can imagine some worst-case scenarios here!) but then notices before they save the page, that temporary image might have already been displayed and viewed on the frontend via getUnformatted().

[horst]

Ok, I see. But I also every time use ProCache(d) sites and the authors do know that they can edit a page without changes on the front end as long as they do not save it. But I see, it isn't that "bullet-proof" I thought it is, (in the front end too). Thanks for pointing that out!

[olafgleba]

10 hours ago, horst said:

I believe you are using a single images field, means the allowed amount of stored image is set to 1.

If that is true, the scope where you calling it is important. [...]

@horst Your assumptions were all right. Argh, it happened quite more than once that i simply forgot about that. Thank you very much for your brief and clear explanation.

@bernhard @Robin S Big thanks also for your advice and details.

[bernhard]

Thx @Robin S I definitely didn't have that on my radar!

Do you have a suggestion what to use if I just want to make sure to get the images' field data as array independently from the template context but not showing temporary or unpublished items?

[horst]

@bernhard At first glance this can work, but I need to do some thorough tests against different cases/situations/states a page and images can have.
It's just the first shot that came to my mind:

$page->getUnformatted('images')->find("created<{$page->modified}")

 

[Robin S]

11 hours ago, bernhard said:

Do you have a suggestion what to use if I just want to make sure to get the images' field data as array independently from the template context but not showing temporary or unpublished items?

I think a couple of ways are possible. One is similar to what @horst suggested, but you can use the special created timestamp of 10 to more exactly identify temporary images:

$page->getUnformatted('images')->find('created!=10')

There are also the public Pagefile::isTemp() and Pagefiles::isTemp() methods that can be used to check if a particular Pagefile/Pageimage is temporary or not.

Another way would be to set the outputFormat property of the images field to array before you get the field value so that the value is standardised for single and multiple image fields.

$page->getField('image')->outputFormat = FieldtypeFile::outputFormatArray;
// Now use $page->image

 

[adrian]

Would $pagefile->isTemp() be of use here?
https://github.com/processwire/processwire/blob/06325993851113436b20b375a6b08cbf38230657/wire/core/Pagefile.php#L1330

I use it in CustomUploadNames

[bernhard]

Just for reference Ryan was very quick on this one and we now have this selector to force return the array value of an image field:

$page->get('image[]')