gzip compress assets and images

[joerg1985]

This PR will enable gzip compression for /assets/* and /images/* with more mime types.
In the past the precompressed files where used, but this is currently broken and a deprecated Jetty feature.
So i does not make sense for me to fix using the precompressed files, as the support has been removed in Jetty 10+.

Before the 5 MB javascript was not compressed:

Now the 5 MB file is compressed to 1.16 MB

[kaikreuzer]

In the past the precompressed files were used

Do they still exist anywhere and should they now be removed?

[kaikreuzer]

Thanks!

[dilyanpalauzov]

openhab/openhab-webui#2481 and openhab/openhab-webui#1432 was/is supposed to alter the webserver to deliver compressed files, when the browser announces support for these with Accept-Encoding: gzip, deflate, br.

The changes in openhab/openhab-webui#1521 were not sufficient to make openHAB deliver pre-compressed .js files.

Is this change now delivering the compressed files, and:

• are files compressed when requested,
• are files compressed when openHAB is built?

[joerg1985]

are files compressed when requested,
Yes

are files compressed when openHAB is built?
Yes, there ist still code in the webui repo related handing the precompressed files.

[dilyanpalauzov]

are files compressed when requested,

Yes

The question was if the files are compressed on the fly. With openHAB 5.2.0 build 5227 my observation is that indeed many things are returned gziz-compressed, which previously used no compression. But HTML responses for /overview and GET /auth ` are returned uncompressed:

• This returns 12.6kb uncompressed:

curl 'https://192.168.0.12:8443/auth?response_type=code&client_id=https%3A%2F%2F192.168.0.12%3A8443&redirect_uri=https%3A%2F%2F192.168.0.12%3A8443&scope=admin&code_challenge_method=S256&code_challenge=DPABCd83nDxcDsk-uuuqkhjAbSTut5ez9Jsl2HlTiL3M&state=ead8465uuuu \
  -H 'accept: text/html,application/xhtml+xml,application/xml;q=0.9,image/avif,image/webp,image/apng,*/*;q=0.8,application/signed-exchange;v=b3;q=0.7' \
  -H 'accept-language: en-GB,en-US;q=0.9,en;q=0.8' \
  -H 'cache-control: no-cache' \
  -H 'pragma: no-cache' \
  -H 'priority: u=0, i' \
  -H 'referer: https://192.168.0.12:8443/overview/' \
  -H 'sec-ch-ua: "Chromium";v="145", "Not:A-Brand";v="99"' \
  -H 'sec-ch-ua-mobile: ?0' \
  -H 'sec-ch-ua-platform: "Linux"' \
  -H 'sec-fetch-dest: document' \
  -H 'sec-fetch-mode: navigate' \
  -H 'sec-fetch-site: same-origin' \
  -H 'sec-fetch-user: ?1' \
  -H 'upgrade-insecure-requests: 1' \
  -H 'user-agent: Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/145.0.0.0 Safari/537.36' \
  --insecure

• This returns 4.0kb uncompressed

curl 'https://192.168.0.12:8443/overview/' \
  -H 'accept: text/html,application/xhtml+xml,application/xml;q=0.9,image/avif,image/webp,image/apng,*/*;q=0.8,application/signed-exchange;v=b3;q=0.7' \
  -H 'accept-language: en-GB,en-US;q=0.9,en;q=0.8' \
  -H 'cache-control: no-cache' \
  -b 'X-OPENHAB-SESSIONID=88a5210c-6a0a-4912-8d6e-255631001d76' \
  -H 'pragma: no-cache' \
  -H 'priority: u=0, i' \
  -H 'sec-ch-ua: "Chromium";v="145", "Not:A-Brand";v="99"' \
  -H 'sec-ch-ua-mobile: ?0' \
  -H 'sec-ch-ua-platform: "Linux"' \
  -H 'sec-fetch-dest: document' \
  -H 'sec-fetch-mode: navigate' \
  -H 'sec-fetch-site: none' \
  -H 'sec-fetch-user: ?1' \
  -H 'upgrade-insecure-requests: 1' \
  -H 'user-agent: Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/145.0.0.0 Safari/537.36' \
  --insecure

[joerg1985]

I think the best would be not to use a include list of paths and mime types, instead using an exclude list for mime types. So only some image types can get excluded.

[dilyanpalauzov]

When I look in org.openhab.ui-5.2.0-SNAPSHOT.jar from openHAB built 5229 I see that app/assets/index-BC_AFnOV.js and app/assets/openhab-logo-BcJrHiEZ.svg are included three times: uncompressed, with .gz and with .br file extension. But in the browser they are delivered only as gzip. Even if reorder the Accept-Encoding: gzip, deflate, br, zstd to have gzip after br or not to have gzip, the br compressed files are never returned.

If formats will be excluded, then .woff and .woff2 should be excluded too, as these are already compressed.

In BasicUI the returned js/css files are not delivered compressed.

Thinking on this again, it is actually fine to compress some data when MainUI/BasicUI are built, and deliver these files compressed to browsers. Everything else can be compressed on the fly, when the resource is requested, by a HTTP proxy between the internet and openHAB. (The latter does not work, if openHAB acts without a HTTP proxy, but is accessed from internet by using VPN).