Opened 3 years ago
Last modified 3 years ago
#54192 new defect (bug)
`get_header_image_tag` doesn't add `srcset`/`sizes`
Reported by: | strarsis | Owned by: | |
---|---|---|---|
Milestone: | Awaiting Review | Priority: | normal |
Severity: | normal | Version: | |
Component: | General | Keywords: | reporter-feedback |
Focuses: | Cc: |
Description
Currently the get_header_image_tag
method (and all other methods calling it like the_custom_header_markup
and get_custom_header_markup
) outputs an <img>
without srcset
and sizes
attributes.
This is important for header images that are normally quite large.
The custom header image method doesn't use the normal WordPress wp_get_attachment_image
method for outputting the actual <img>
, instead it constructs the <img>
markup with its own code.
Related issue: https://core.trac.wordpress.org/ticket/46134#comment:6
Change History (8)
#2
in reply to:
↑ 1
@
3 years ago
Replying to joyously:
The
srcset
andsizes
are added later, for all the images that have awp-image-*
class. The image id is needed to do the lookup for the data to use.
How are these attributes added later? Does WordPress parse the HTML and add them directly?
The function uses a filter, but it doesn't seem to be used elsewhere as the srcset and sizes attributes are missing.
https://github.com/WordPress/WordPress/blob/07139653b9f1b8b1cc88195b971e96597fbc8b10/wp-includes/theme.php#L1200
#3
follow-up:
↓ 4
@
3 years ago
Let me amend my statement. For post content, the srcset
and sizes
are added later, by wp_filter_content_tags()
.
The get_header_image_tag()
function adds the attributes itself, just below where you referenced. Does your test case meet the condition?
if ( empty( $attr['srcset'] ) && ! empty( $header->attachment_id ) )
#4
in reply to:
↑ 3
;
follow-up:
↓ 6
@
3 years ago
Replying to joyously:
Let me amend my statement. For post content, the
srcset
andsizes
are added later, bywp_filter_content_tags()
.
Theget_header_image_tag()
function adds the attributes itself, just below where you referenced. Does your test case meet the condition?
if ( empty( $attr['srcset'] ) && ! empty( $header->attachment_id ) )
Good point. The test case would meet the condition, as $attr
doesn't contain srcset
and by default srcset
is not added to $attr
.
This ticket was mentioned in Slack in #core-test by hellofromtonya. View the logs.
3 years ago
#6
in reply to:
↑ 4
;
follow-up:
↓ 7
@
3 years ago
- Keywords reporter-feedback added
Hello @strarsis,
Welcome back to Core's Trac! Thank you for the ticket.
Replying to strarsis:
Good point. The test case would meet the condition, as
$attr
doesn't containsrcset
and by defaultsrcset
is not added to$attr
.
Does this resolve the ticket and your test case? Or is it still not generating the srcset
and size
?
If the problem remains, check the _wp_attachment_metadata
for the attachment (see the code on about L1226). Is it an array? If no, then the generation is skipped.
If it is an array and the generation is not happening, please share step-by-step instructions including any code or attachments for contributors to reproduce the problem. This type of information helps contributors to investigate.
#7
in reply to:
↑ 6
@
3 years ago
Replying to hellofromTonya:
Hello @strarsis,
Welcome back to Core's Trac! Thank you for the ticket.
Replying to strarsis:
Good point. The test case would meet the condition, as
$attr
doesn't containsrcset
and by defaultsrcset
is not added to$attr
.
Does this resolve the ticket and your test case? Or is it still not generating the
srcset
andsize
?
If the problem remains, check the
_wp_attachment_metadata
for the attachment (see the code on about L1226). Is it an array? If no, then the generation is skipped.
If it is an array and the generation is not happening, please share step-by-step instructions including any code or attachments for contributors to reproduce the problem. This type of information helps contributors to investigate.
I prepared a minimal sample theme that demonstrates the issue:
https://github.com/strarsis/wp-test-theme-customheader-srcsetsizes
When a custom header image is specified, the default WordPress functions output an <img
element without the srcset
and sizes
attributes.
#8
@
3 years ago
Currently I have to use the following code to add srcset
/sizes
to the generated custom header image:
<?php function get_attachment_id_by_rel_url($url) { $url_abs = home_url($url); $attachment = attachment_url_to_postid($url_abs); return $attachment; } add_filter('get_header_image_tag', function ($default_html, $header_obj, $attr) { $header_image_src = $attr['src']; $header_image_attachment_id = get_attachment_id_by_rel_url($header_image_src); $header_image_html = wp_get_attachment_image( $header_image_attachment_id, 'header-image', false, $attr, ); return $header_image_html; }, 5, 3);
Note that as the passed header object doesn't contain the actual custom image src (this may be a plugin issue and unrelated to this issue), I have to determine the attachment ID by using its URL.
The
srcset
andsizes
are added later, for all the images that have awp-image-*
class. The image id is needed to do the lookup for the data to use.