Cache control headers are missing when SDC is not pre-generated

[ihor-sviziev]

Preconditions (*)

1. Apache 2.4 + php 7.2
2. Magento 2.3.3 or 2.3-develop
3. Magento mode: default, developer OR production with enabled SCD on demand and without running static content deploy

This issue isn't reproducing in production mode with compiled static content and not reproducing with nginx+php_fpm.

Steps to reproduce (*)

Case 1:

1. Open Google Chrome developer tools
2. Navigate to homepage
3. In Google Chrome dev tools looks at any .js file (I checked on domReady.js file), look at "Response Headers" section
4. Refresh the page, find the same JS file, looks at "Response Headers"

Case 2:
Try to curl some js file from Magento/blank two times(because you never request it before):

Expected result (*)

1. First time file should contains Cache-Control header
2. Second time should also contains Cache-Control header

Actual result (*)

1. At first time Cache-Control header is missing
   

2. At second time - this header is there
   

Additional info

In case if we'll have CDN - first response will be cached for many people and browser will not cache JS files in browser's cache. Also there are another headers missing (see screenshots) that could create incorrect behavior.

This issue caused by redirecting to static.php file when real .js file doesn't exists, and adding Cache-Control header isn't applying.

magento2/pub/static/.htaccess

Lines 75 to 77 in dfffe34

	<FilesMatch .*\.(ico|jpg|jpeg|png|gif|svg|js|css|swf|eot|ttf|otf|woff|woff2|json)$>
	Header append Cache-Control public
	</FilesMatch>

[m2-assistant]

Hi @ihor-sviziev. Thank you for your report.
To help us process this issue please make sure that you provided the following information:

• Summary of the issue
• Information on your environment
• Steps to reproduce
• Expected and actual results

Please make sure that the issue is reproducible on the vanilla Magento instance following Steps to reproduce. To deploy vanilla Magento instance on our environment, please, add a comment to the issue:

@magento give me 2.3-develop instance - upcoming 2.3.x release

For more details, please, review the Magento Contributor Assistant documentation.

@ihor-sviziev do you confirm that you were able to reproduce the issue on vanilla Magento instance following steps to reproduce?

• yes
• no

---

• Join Magento Community Engineering Slack and ask your questions in #github channel.

[m2-assistant]

Hi @engcom-Charlie. Thank you for working on this issue.
In order to make sure that issue has enough information and ready for development, please read and check the following instruction: 👇

• 1. Verify that issue has all the required information. (Preconditions, Steps to reproduce, Expected result, Actual result).

  Details

  If the issue has a valid description, the label Issue: Format is valid will be added to the issue automatically. Please, edit issue description if needed, until label Issue: Format is valid appears.

• 2. Verify that issue has a meaningful description and provides enough information to reproduce the issue. If the report is valid, add Issue: Clear Description label to the issue by yourself.

• 3. Add Component: XXXXX label(s) to the ticket, indicating the components it may be related to.

• 4. Verify that the issue is reproducible on 2.3-develop branch

  Details

  - Add the comment @magento give me 2.3-develop instance to deploy test instance on Magento infrastructure.
  - If the issue is reproducible on 2.3-develop branch, please, add the label Reproduced on 2.3.x.
  - If the issue is not reproducible, add your comment that issue is not reproducible and close the issue and stop verification process here!

• 5. Add label Issue: Confirmed once verification is complete.

• 6. Make sure that automatic system confirms that report has been added to the backlog.

[engcom-Charlie]

@magento give me 2.3-develop instance

[magento-engcom-team]

Hi @engcom-Charlie. Thank you for your request. I'm working on Magento 2.3-develop instance for you

[magento-engcom-team]

Hi @engcom-Charlie, here is your Magento instance.
Admin access: https://i-25578-2-3-develop.instances.magento-community.engineering/admin
Login: admin Password: 123123q
Instance will be terminated in up to 3 hours.

[engcom-Charlie]

@magento give me 2.3-develop instance

[magento-engcom-team]

Hi @engcom-Charlie. Thank you for your request. I'm working on Magento 2.3-develop instance for you

[magento-engcom-team]

Hi @engcom-Charlie, here is your Magento instance.
Admin access: https://i-25578-2-3-develop.instances.magento-community.engineering/admin
Login: admin Password: 123123q
Instance will be terminated in up to 3 hours.