feat: add gzip pre-compression for static assets to improve load time by RomanNikitenko · Pull Request #761 · che-incubator/che-code

RomanNikitenko · 2026-07-17T15:20:54Z

What does this PR do?

Pre-compresses JS/CSS/HTML/JSON files during Docker build (gzip -9)
Serves .gz files directly when client supports Accept-Encoding: gzip
Falls back to uncompressed files if .gz is missing or on any error
Adds CODE_DISABLE_STATIC_GZIP=1 env variable as kill switch

Expected improvement:

workbench.js transfer drops from ~16MB to ~4.4MB: (~3.7x reduction),
significantly reducing white screen time https://redhat.atlassian.net/browse/CRW-10327
zero risk of regression: if .gz files don't exist or env variable is set, the server behaves exactly as before

Before:

After:

What issues does this PR fix?

https://redhat.atlassian.net/browse/CRW-10327

How to test this PR?

Does this PR contain changes that override default upstream Code-OSS behavior?

the PR contains changes in the code folder (you can skip it if your changes are placed in a che extension )
the corresponding items were added to the CHANGELOG.md file
rules for automatic git rebase were added to the .rebase folder

Assisted-by: Cursor AI

github-actions · 2026-07-17T15:21:06Z

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tolusha · 2026-07-17T15:24:37Z

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github-actions · 2026-07-17T16:40:07Z

Pull Request images published ✨

Editor amd64: quay.io/che-incubator-pull-requests/che-code:pr-761-amd64
Editor arm64: quay.io/che-incubator-pull-requests/che-code:pr-761-arm64
Dev image: quay.io/che-incubator-pull-requests/che-code-dev:pr-761-dev-amd64

rgrunber · 2026-07-17T17:32:47Z

I'm not seeing a huge improvement in speed, but there's definitely less data being transferred. It might make a difference on slower connections.

Before

workbench.js	dom	load	finish (s)	total transfer
1.24s	334ms	4.39s	19.64s	19.82MB
770ms	436ms	3.94s	16.65s	19.82MB
508ms	447ms	3.85s	16.32s	19.82MB
1.05s	502ms	4.22s	17.09s	19.82MB
3.27s	437ms	6.36s	19.15s	19.82MB

After

workbench.js	dom	load	finish (s)	total transfer
894ms	447ms	4.24s	18.03s	6.40MB
793ms	287ms	4.03s	18.09s	6.40MB
635ms	437ms	3.89s	17.78s	6.36MB
567ms	362ms	3.78s	18.50s	6.36MB
472ms	232ms	3.64s	17.25s	6.36MB

Signed-off-by: Roman Nikitenko <rnikiten@redhat.com> Assisted-by: Cursor AI

Ensure the Promise in tryServeCompressedFile settles when the client disconnects or a stream error occurs after headers are sent. Previously these scenarios left the Promise pending, which could hang the request handler. Signed-off-by: Roman Nikitenko <rnikiten@redhat.com>

github-actions · 2026-07-21T14:40:15Z

Pull Request images published ✨

Editor amd64: quay.io/che-incubator-pull-requests/che-code:pr-761-amd64
Editor arm64: quay.io/che-incubator-pull-requests/che-code:pr-761-arm64
Dev image: quay.io/che-incubator-pull-requests/che-code-dev:pr-761-dev-amd64

coderabbitai · 2026-07-22T11:16:02Z

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.rebase/replace/code/src/vs/server/node/webClientServer.ts.json
build/dockerfiles/linux-libc-ubi8.Dockerfile
build/dockerfiles/linux-libc-ubi9.Dockerfile
build/dockerfiles/linux-musl.Dockerfile
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Skip gzip serving when the client explicitly refuses gzip by setting quality value to zero (e.g. Accept-Encoding: gzip;q=0). Signed-off-by: Roman Nikitenko <rnikiten@redhat.com> Co-authored-by: Cursor <cursoragent@cursor.com>

Add Vary header before ETag/304 conditional so shared caches correctly distinguish compressed and uncompressed variants. Include responseHeaders in 304 response to propagate Vary to the client. Signed-off-by: Roman Nikitenko <rnikiten@redhat.com> Co-authored-by: Cursor <cursoragent@cursor.com>

…nges Add rebase replace rules to cover the Che-specific modifications to code/src/vs/server/node/webClientServer.ts introduced for HTTP pre-compression support: - Import tryServeCompressedFile from che/webClientServer.js - Add Vary: Accept-Encoding header before ETag check - Pass responseHeaders to 304 response for proper cache behavior - Insert tryServeCompressedFile call before raw file streaming These rules ensure the compression changes survive upstream rebases without manual conflict resolution. Signed-off-by: Roman Nikitenko <rnikiten@redhat.com> Co-authored-by: Cursor <cursoragent@cursor.com>

github-actions · 2026-07-22T12:59:57Z

Pull Request images published ✨

Editor amd64: quay.io/che-incubator-pull-requests/che-code:pr-761-amd64
Editor arm64: quay.io/che-incubator-pull-requests/che-code:pr-761-arm64
Dev image: quay.io/che-incubator-pull-requests/che-code-dev:pr-761-dev-amd64

github-actions · 2026-07-22T13:54:22Z

Pull Request images published ✨

Editor amd64: quay.io/che-incubator-pull-requests/che-code:pr-761-amd64
Editor arm64: quay.io/che-incubator-pull-requests/che-code:pr-761-arm64
Dev image: quay.io/che-incubator-pull-requests/che-code-dev:pr-761-dev-amd64

RomanNikitenko mentioned this pull request Jul 17, 2026

Dev Tools Week Q3 2026 eclipse-che/che#23835

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22 tasks

RomanNikitenko mentioned this pull request Jul 17, 2026

feat: switch to esbuild-based build pipeline for faster builds #762

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RomanNikitenko added 2 commits July 21, 2026 15:16

feat: add gzip pre-compression for static assets to improve load time

6ee08de

Signed-off-by: Roman Nikitenko <rnikiten@redhat.com> Assisted-by: Cursor AI

RomanNikitenko force-pushed the reduce-ide-loading branch from 9fa1932 to 0211751 Compare July 21, 2026 12:17

RomanNikitenko marked this pull request as ready for review July 22, 2026 11:15

RomanNikitenko requested review from azatsarynnyy, rgrunber and vitaliy-guliy as code owners July 22, 2026 11:15

RomanNikitenko and others added 3 commits July 22, 2026 15:13

fix: honor gzip;q=0 refusal in Accept-Encoding header

00f0634

Skip gzip serving when the client explicitly refuses gzip by setting quality value to zero (e.g. Accept-Encoding: gzip;q=0). Signed-off-by: Roman Nikitenko <rnikiten@redhat.com> Co-authored-by: Cursor <cursoragent@cursor.com>

RomanNikitenko force-pushed the reduce-ide-loading branch from 5299497 to aad2768 Compare July 22, 2026 12:14

rgrunber reviewed Jul 22, 2026

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feat: add gzip pre-compression for static assets to improve load time - #761

feat: add gzip pre-compression for static assets to improve load time#761
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