Problem/Motivation

#2800873: Add XML GET REST test coverage, work around XML encoder quirks managed to finally get decent test coverage for the xml serialization format. Which means that GETting entities (reading them) is finally supportable/maintainable, because we'll be notified of BC breaks via failing tests.

However, there's still lots of peculiarities there (as discussed in the first several dozen comments on that issue). So I don't think it's something we'd like to support in Drupal 9. Especially because writing XML still is not supported.

Proposed resolution

Deprecate the xml format in Drupal 9.

Remaining tasks

Discuss.

User interface changes

None.

API changes

None.

Data model changes

None.

CommentFileSizeAuthor
#2 2926034-2.patch1.92 KBWim Leers
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Comments

Wim Leers created an issue. See original summary.

Wim Leers’s picture

Wim Leers
Location Ghent 🇧🇪🇪🇺
CreditAttribution: Wim Leers at Acquia commented
Status: Active » Needs review
FileSize
2926034-2.patch1.92 KB

Status: Needs review » Needs work

The last submitted patch, 2: 2926034-2.patch, failed testing. View results

Version: 8.5.x-dev » 8.6.x-dev

Drupal 8.5.0-alpha1 will be released the week of January 17, 2018, which means new developments and disruptive changes should now be targeted against the 8.6.x-dev branch. For more information see the Drupal 8 minor version schedule and the Allowed changes during the Drupal 8 release cycle.

Version: 8.6.x-dev » 8.7.x-dev

Drupal 8.6.0-alpha1 will be released the week of July 16, 2018, which means new developments and disruptive changes should now be targeted against the 8.7.x-dev branch. For more information see the Drupal 8 minor version schedule and the Allowed changes during the Drupal 8 release cycle.

Wim Leers’s picture

Wim Leers
Location Ghent 🇧🇪🇪🇺
CreditAttribution: Wim Leers at Acquia commented
Issue tags: +Drupal 9
dawehner’s picture

dawehner
Primary language German
CreditAttribution: dawehner at Chapter Three commented

It feels like XML is a really rare used feature. I don't think we have any further data for this, don't we?
I think one argument in favour of deprecating the XML based encoding is that there is nothing blocking you from implementing a custom XML encoder/decoder for your own project or in contrib.
I could imagine that actually in reality you would need a custom way anyway, as certain systems use certain XML schemas already anyway.

Wim Leers’s picture

Wim Leers
Location Ghent 🇧🇪🇪🇺
CreditAttribution: Wim Leers at Acquia commented

#7: exactly! And we know of at least two cases of that: #2800873-21: Add XML GET REST test coverage, work around XML encoder quirks and #2824837: Change the root node name of a custom REST resource's XML encoding.

Version: 8.7.x-dev » 8.8.x-dev

Drupal 8.7.0-alpha1 will be released the week of March 11, 2019, which means new developments and disruptive changes should now be targeted against the 8.8.x-dev branch. For more information see the Drupal 8 minor version schedule and the Allowed changes during the Drupal 8 release cycle.

mradcliffe’s picture

mradcliffe
he/him
Primary language English
CreditAttribution: mradcliffe at Kosada commented

I find XmlEncoder useful when I'm writing unit tests, and having it removed or marked as @internal would make it hard for me to write pure unit tests because I would get deprecated or internal warnings in my IDE.

It's not necessarily true that APIs have complex XSD-capable definitions requiring a custom encoder. Plain-old XML (POX) is still used.

I don't really want to write and maintain my own POX encoder when it's already supported in Serializer or serialization module.

Wim Leers’s picture

Wim Leers
Location Ghent 🇧🇪🇪🇺
CreditAttribution: Wim Leers as a volunteer commented

Interesting. Why do you specifically find it useful when writing unit tests?

mradcliffe’s picture

mradcliffe
he/him
Primary language English
CreditAttribution: mradcliffe at Kosada commented

Using Symfony's XmlEncoder seems to work for me in unit tests, but the lack of NormalizationAwareInterface is probably helpful/useful/how-I-can normalize and denormalize xero api requests/responses. I'm using the

I think it would be possible to remove from core, but it would be a pain to have to install or maintain a contrib module only to re-add a wrapper to Symfony's XmlEncoder back.

The current change record sounds scary to me because it makes it seem like we're removing something as useful as XML, which is still used despite the hotness of JSON. Maybe rewording this to include alternatives if ripping out support for XML serialization is really necessary?

Version: 8.8.x-dev » 8.9.x-dev

Drupal 8.8.0-alpha1 will be released the week of October 14th, 2019, which means new developments and disruptive changes should now be targeted against the 8.9.x-dev branch. (Any changes to 8.9.x will also be committed to 9.0.x in preparation for Drupal 9’s release, but some changes like significant feature additions will be deferred to 9.1.x.). For more information see the Drupal 8 and 9 minor version schedule and the Allowed changes during the Drupal 8 and 9 release cycles.

Wim Leers’s picture

Wim Leers
Location Ghent 🇧🇪🇪🇺
CreditAttribution: Wim Leers at Acquia commented
Title: Deprecate 'xml' serialization format in Drupal 9 » Deprecate 'xml' serialization format in Drupal 10
Issue tags: -Drupal 9

Version: 8.9.x-dev » 9.1.x-dev

Drupal 8.9.0-beta1 was released on March 20, 2020. 8.9.x is the final, long-term support (LTS) minor release of Drupal 8, which means new developments and disruptive changes should now be targeted against the 9.1.x-dev branch. For more information see the Drupal 8 and 9 minor version schedule and the Allowed changes during the Drupal 8 and 9 release cycles.

Version: 9.1.x-dev » 9.2.x-dev

Drupal 9.1.0-alpha1 will be released the week of October 19, 2020, which means new developments and disruptive changes should now be targeted for the 9.2.x-dev branch. For more information see the Drupal 9 minor version schedule and the Allowed changes during the Drupal 9 release cycle.

Version: 9.2.x-dev » 9.3.x-dev

Drupal 9.2.0-alpha1 will be released the week of May 3, 2021, which means new developments and disruptive changes should now be targeted for the 9.3.x-dev branch. For more information see the Drupal core minor version schedule and the Allowed changes during the Drupal core release cycle.

Version: 9.3.x-dev » 9.4.x-dev

Drupal 9.3.0-rc1 was released on November 26, 2021, which means new developments and disruptive changes should now be targeted for the 9.4.x-dev branch. For more information see the Drupal core minor version schedule and the Allowed changes during the Drupal core release cycle.

Version: 9.4.x-dev » 9.5.x-dev

Drupal 9.4.0-alpha1 was released on May 6, 2022, which means new developments and disruptive changes should now be targeted for the 9.5.x-dev branch. For more information see the Drupal core minor version schedule and the Allowed changes during the Drupal core release cycle.

Version: 9.5.x-dev » 10.1.x-dev

Drupal 9.5.0-beta2 and Drupal 10.0.0-beta2 were released on September 29, 2022, which means new developments and disruptive changes should now be targeted for the 10.1.x-dev branch. For more information see the Drupal core minor version schedule and the Allowed changes during the Drupal core release cycle.

Version: 10.1.x-dev » 11.x-dev

Drupal core is moving towards using a “main” branch. As an interim step, a new 11.x branch has been opened, as Drupal.org infrastructure cannot currently fully support a branch named main. New developments and disruptive changes should now be targeted for the 11.x branch, which currently accepts only minor-version allowed changes. For more information, see the Drupal core minor version schedule and the Allowed changes during the Drupal core release cycle.