Opened 4 months ago
Last modified 8 days ago
#35535 assigned New feature
Provide new template tag to capture internal block output as a template variable ("simple block tag").
Reported by: | Jake Howard | Owned by: | Jake Howard |
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Component: | Template system | Version: | dev |
Severity: | Normal | Keywords: | |
Cc: | Carlton Gibson, Sébastien Corbin | Triage Stage: | Accepted |
Has patch: | yes | Needs documentation: | no |
Needs tests: | no | Patch needs improvement: | no |
Easy pickings: | no | UI/UX: | no |
Description
Django's template system allows creating custom tags, but they don't allow taking content:
{% mysimpletag foo="bar" %}
However there are plenty of use-cases where it'd be useful to also collect content along with the tag, turning it into a "block" tag:
{% mysimpletag foo="bar" %} This content gets captured too {% endmysimpletag %}
This currently requires using complex internals of the template system (some documented, some not) to achieve. The cache tag is a good example of this kind of "simple" block, which requires some parser internals.
I propose adding a @register.simple_block
method to allow easy registering of custom block tags. The API would be similar to simple_tag
, however with a required content
argument containing the (rendered) template content:
@register.simple_block(takes_context=True) def mysimpletag(context: Context, content: str, foo: str) -> str: return f"foo = {foo}"
(Types added for reference)
I have a working demo of this I can push up.
Change History (21)
comment:1 by , 4 months ago
Resolution: | → wontfix |
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Status: | assigned → closed |
comment:2 by , 4 months ago
For now, I've now raised this on the forum: https://forum.djangoproject.com/t/feature-proposal-simple-block-tag/32229. Will collect feedback, and then return!
comment:3 by , 4 months ago
Cc: | added |
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comment:4 by , 3 months ago
Has patch: | set |
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Resolution: | wontfix |
Status: | closed → new |
Following a few conversations on the forum thread, I've opened a [PR https://github.com/django/django/pull/18343].
comment:5 by , 3 months ago
Triage Stage: | Unreviewed → Accepted |
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Version: | 5.0 → dev |
Thank you Jake for following up on this. I think the forum post shows enough agreement, and I personally also think this is a useful adding. I also agree with related comments from #6378, specifically:
I do think there are cases where the "capture" model is the appropriate one, and it ought to be built-in.
I considered reopening #6378 and closing this as a dupe, but I decided not to because the older ticket is a bit confusing in how the problem is described because there is a mix of requirements which some were solved by #18651.
comment:6 by , 3 months ago
Summary: | Simple block tag → Provide new template tag to capture internal block output as a template variable ("simple block tag"). |
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comment:7 by , 3 months ago
Owner: | changed from | to
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Status: | new → assigned |
comment:8 by , 3 months ago
Owner: | changed from | to
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Hello Sushmita Palikhe! Thank you for your interest in contributing to Django, but this ticket is already owned by Jake and their work is still active.
comment:10 by , 3 months ago
Owner: | set to |
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Yes, definitely still active. The draft PR is linked above though, and I'd definitely welcome any comments / suggestions you may have.
comment:11 by , 2 months ago
Cc: | added |
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comment:13 by , 2 months ago
I do think there are cases where the "capture" model is the appropriate one, and it ought to be built-in.
Currently, the simple block is added with a related implementation. It should be simple enough to use it to implement a capture
tag, but I wasn't going to add it to the existing PR to avoid scope-creep. I can if you think it'd be better?
comment:14 by , 8 weeks ago
@Jake I’d keep the scope as is. Let’s let folks build with the new tag (IMO)
comment:15 by , 8 weeks ago
Patch needs improvement: | set |
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comment:16 by , 8 weeks ago
Patch needs improvement: | unset |
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comment:17 by , 5 weeks ago
Patch needs improvement: | set |
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comment:18 by , 5 weeks ago
Patch needs improvement: | unset |
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comment:19 by , 5 weeks ago
Patch needs improvement: | set |
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comment:20 by , 5 weeks ago
Patch needs improvement: | unset |
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comment:21 by , 3 weeks ago
Patch needs improvement: | set |
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I gave this another top-bottom pass. Once the minor nitpicks are fixed, I need to do a in-depth review in terms of test coverage and functionality.
comment:22 by , 8 days ago
Patch needs improvement: | unset |
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Hi Jake👋 thank you for raising this, I can see why this could be useful.
For a feature request to be accepted, we want to see some discussion on the forum first to confirm/validate the feature with the community and get some feedback.
I'll close the ticket for now, but if there is a community agreement for this, you are welcome to come back linking the forum topic, so we can then re-open it.
For more details, please see the documented guidelines for requesting features 👍