Views do not respect "Date format" setting in a "REST Export" display

Thanks for the detailed issue decsription. I tried to recreate this issue wirh the given view configuration in Drupal 10.2.2 & Drupal 11 versions and these are the observations.

If custom date format is selected and 'U' is given as the format, Timestamp value of the date appeares correctly in the response.
If another custom date format is used (Eg: m/d/Y), date gets correctly formated in the response.

Feels similar to 🐛 Views RSS Feed Fields adds tag. Active and probably also caused by 🐛 Allow TimestampFormatter to show as a fully cacheable time difference with JS Fixed

@Lendude those issues look similar, indeed, but they are marked as fixed, while I can still reproduce this issue by importing the attached `views.view.test.yml` file into a fresh Drupal 10.3.2 instance.

@akhil babu you are correct. With the latest Drupal version, the "Date format" is respected, but the whole thing is still wrapped in HTML. I'll update the title and description of this issue.

Partial workaround: Enable "Strip HTML tags" and "Remove whitespace" under "Rewrite results" when configuring the views field. The only problem is that it's still a string instead of an int when using "U" as the "Date format".

@rudolfbyker has correctly identified a bug that should be squashed.

When exporting your nodes as json, you'd probably want to be able to easily export your dates in some easily machine-readable format.

For a project I'm currently working on
05.12.2024 - 17:11
is WAY superior to
<time datetime="2024-12-05T17:11:05+01:00">05.12.2024 - 17:11</time>\n

Silly workaround that works for me, but should only be temporary:
In the view, configuring the date fields: rewrite the result. Remove HTML tags and trim it to 18 characters (no ellipsis).

Another workaround:
Ask for "raw output" at Format - Fields - Config.
This will give you a timestamp, no HTML.

The correct solution:
Configuring the field, you should be able to set Formatter as "raw/no html markup"

Removed the tag for unix timestamp in views rest export, below is the patch for it.
tag removed code

@niranjan_panem the patch in #10 is probably better than nothing, but a long term useful solution.

Before patching:
Ask for "raw output" at Format - Fields - Config. This will give you a timestamp, no HTML.

After patching:
Ask or Custom: U at Date Format. This will give you a timestamp, no HTML.

What we need is
The correct solution:
Configuring the field, you should be able to set Formatter as "raw/no html markup"
Default/Time Ago just doesn't cut it as formatting options.

The Needs Review Queue Bot → tested this issue. It fails the Drupal core commit checks. Therefore, this issue status is now "Needs work".

This does not mean that the patch necessarily needs to be re-rolled or the MR rebased. Read the Issue Summary, the issue tags and the latest discussion here to determine what needs to be done.

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