Distroless builds: Lua, Perl and Php Distroless Builds by cosmintanasa47 · Pull Request #460 · unikraft-cloud/examples

cosmintanasa47 · 2026-09-05T18:45:02Z

Those are the 3 distroless versions for the 3 examples present in the title. Details on each file's content in the commit messages.

First stage resolves dependencies, the second stage runs the server. Didn't find a lua specific distroless image so I started to build from the cc-debian distroless image, adding necessary libraries. The image already contains some useful libraries.

Slightly modify to fit the new distroless version.

Slightly modify to fit new distroless version.

Unmodified files from non-distroless original version.

First stage resolves dependencies, the second stage runs the server. Didn't find a perl distroless image and used cc-debian12 as distroless image to have maximum compatibility with the build stage image. Didn't add duplicate libraries.

Slightly modified to fit new distroless version.

Slightly modify to fit new distroless version.

Unmodified files from non-distroless version.

Copilot

🟡 Changes recommended

The PHP distroless image wiring has correctness issues (extension placement/config duplication and interpreter path consistency) and the PHP server should fail fast on socket setup failures.

Once you've addressed the issues Copilot identified, you can request another Copilot review.

Pull request overview

Adds three new “distroless” variants of existing HTTP server examples (Lua 5.1, Perl 5.42, PHP 8.2), including container rootfs definitions, Kraft specs, README deployment guides, and end-to-end tests to validate “Hello, World!” responses on Unikraft Cloud.

Changes:

Introduce new distroless example directories for Lua, Perl, and PHP with Dockerfile+Kraftfile-based root filesystems.
Add language-specific “Hello, World!” server implementations and supporting runtime config (e.g., PHP sockets).
Add E2E pytest coverage for each new distroless example.

File summaries

File	Description
httpserver-php8.2-distroless/test_httpserver-php8.2-distroless.py	New E2E test that builds, runs, and validates the PHP distroless example.
httpserver-php8.2-distroless/server.php	PHP socket-based HTTP server implementation returning “Hello, World!”.
httpserver-php8.2-distroless/rootfs/usr/local/etc/php/php.ini	PHP config enabling sockets extension for the distroless image.
httpserver-php8.2-distroless/README.md	New deployment and usage guide for the PHP distroless example.
httpserver-php8.2-distroless/Kraftfile	Unikraft Cloud specification for running the PHP distroless rootfs.
httpserver-php8.2-distroless/Dockerfile	Distroless-rootfs build for PHP, including sockets extension provisioning.
httpserver-perl5.42-distroless/test_httpserver-perl5.42-distroless.py	New E2E test that builds, runs, and validates the Perl distroless example.
httpserver-perl5.42-distroless/server.pl	Perl HTTP::Daemon-based server returning “Hello, World!”.
httpserver-perl5.42-distroless/README.md	New deployment and usage guide for the Perl distroless example.
httpserver-perl5.42-distroless/Kraftfile	Unikraft Cloud specification for running the Perl distroless rootfs.
httpserver-perl5.42-distroless/Dockerfile	Distroless-rootfs build for Perl runtime + modules.
httpserver-lua5.1-distroless/test_httpserver-lua5.1-distroless.py	New E2E test that builds, runs, and validates the Lua distroless example.
httpserver-lua5.1-distroless/README.md	New deployment and usage guide for the Lua distroless example.
httpserver-lua5.1-distroless/Kraftfile	Unikraft Cloud specification for running the Lua distroless rootfs.
httpserver-lua5.1-distroless/http_server.lua	Lua HTTP server implementation (lua-http) returning “Hello, World!”.
httpserver-lua5.1-distroless/Dockerfile	Distroless-rootfs build for Lua + LuaRocks dependencies.

Review details

Suppressed comments (2)

httpserver-php8.2-distroless/server.php:26

If socket_listen() fails, the script prints an error but then enters the accept loop anyway. Exiting on failure avoids a broken instance that appears deployed but cannot accept connections.

if (socket_listen($sock, 5) === false) {
    echo "socket_listen() failed: reason: " . socket_strerror(socket_last_error($sock)) . "\n";
}

httpserver-php8.2-distroless/server.php:22

If socket_bind() fails, the script currently continues and will attempt to listen()/accept() anyway. Exit early on failure so the instance fails fast instead of hanging or looping with errors.

if (socket_bind($sock, $address, $port) === false) {
    echo "socket_bind() failed: reason: " . socket_strerror(socket_last_error($sock)) . "\n";
}

Files reviewed: 16/16 changed files
Comments generated: 4
Review effort level: Lite

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+if (($sock = socket_create(AF_INET, SOCK_STREAM, SOL_TCP)) === false) {
+    echo "socket_create() failed: reason: " . socket_strerror(socket_last_error()) . "\n";
+}
+


+If a request is not a HEAD method, then reply with "Hello world!"
+
+Usage: lua examples/server_hello.lua [<port>]


First stage installs dependencies, second one runs the server. ghcr.io/opencodeco/distroless-php:8.2 image is the best suited distroless image for this php8.2 http server. It contains all necesary system libraries. Only useful files are copied, no duplicate. Copying the whole extensions folder preserves that versioned subfolder, so PHP finds the .so where it expects it.

Took old Kraftfile and modified the php path to fit the distroless php image ghcr.io/opencodeco/distroless-php:8.2. Previos: /usr/local/bin/php Current: /bin/php

Slightly modified to fit new distroless version.

Unmodified files from non-distroless version.

cosmintanasa47 · 2026-09-10T21:36:37Z

Modified so that the extensions problem and the php executable problem are resolved. Considering that I have to add distroless examples starting from the original non-distroless examples, I have to modify dockerfiles and kraftfiles, not source code. The examples added are tested and they work the same as the "original" ones.

Copilot

🟡 Changes recommended

Unresolved critical Perl and PHP runtime issues block approval; the Perl README command also needs correction.

Once you've addressed the issues Copilot identified, you can request another Copilot review.

Review details

Suppressed comments (1)

httpserver-php8.2-distroless/rootfs/usr/local/etc/php/php.ini:3

The selected ghcr.io/opencodeco/distroless-php:8.2 image ships a static PHP binary with sockets already compiled in, so this setting attempts to load a second copy of the same module from the separately built .so copied by the Dockerfile. That produces a startup warning and can fail if the module ABI differs; remove the dynamic extension copy/configuration or use a base image intended for shared extensions.

extension=sockets

Files reviewed: 16/16 changed files
Comments generated: 3
Review effort level: Lite

+COPY --from=build /usr/local/lib/perl5 /usr/local/lib/perl5
+
+# System libraries
+COPY --from=build /usr/local/lib/perl5/5.42.0/x86_64-linux-gnu/CORE/libperl.so /usr/local/lib/perl5/5.42.0/x86_64-linux-gnu/CORE/libperl.so


+FROM ghcr.io/opencodeco/distroless-php:8.2
+
+# Copy sockets extension and enable it via php.ini.
+COPY --from=build /usr/local/lib/php/extensions/ /usr/local/lib/php/extensions/


+
+**Using the unikraft CLI (Recommended)**
+```bash title="unikraft"
+unikraft instance list --watch


cosmintanasa47 added 8 commits September 5, 2026 21:34

feat: Add httpserver-lua5.1-distroless - Add README.md

002f3ec

Slightly modify to fit the new distroless version.

feat: Add httpserver-lua5.1-distroless - Add python test file

6fed31a

Slightly modify to fit new distroless version.

feat: Add httpserver-lua5.1-distroless - Add Kraftfile and source file

22e5bcd

Unmodified files from non-distroless original version.

feat: Add httpserver-perl5.42-distroless- Add README.md

387791e

Slightly modified to fit new distroless version.

feat: Add httpserver-perl5.42-distroless - Add python test file

a0dc2bd

Slightly modify to fit new distroless version.

feat: Add httpserver-perl5.42-distroless - Add Kraftfile and source file

b177967

Unmodified files from non-distroless version.

razvand requested a lite review from Copilot September 7, 2026 20:18

razvand self-assigned this Sep 7, 2026

Copilot started reviewing on behalf of razvand September 7, 2026 20:18 View session

Copilot AI reviewed Sep 7, 2026

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cosmintanasa47 added 5 commits September 11, 2026 00:21

feat: Add httpserver-php8.2-distroless - Add Kraftfile

85ab06a

Took old Kraftfile and modified the php path to fit the distroless php image ghcr.io/opencodeco/distroless-php:8.2. Previos: /usr/local/bin/php Current: /bin/php

feat: Add httpserver-php8.2-distroless - Add README.md

1b12a33

Slightly modified to fit new distroless version.

feat: Add httpserver-php8.2-distroless - Add python test file

f41c3cc

Slightly modified to fit new distroless version.

feat: Add httpserver-php8.2-distroless - Add unmodified files

ca1cacd

Unmodified files from non-distroless version.

cosmintanasa47 force-pushed the lua-perl-php-distroless branch from 629a293 to ca1cacd Compare September 10, 2026 21:26

cosmintanasa47 requested a lite review from Copilot September 10, 2026 21:38

Copilot started reviewing on behalf of cosmintanasa47 September 10, 2026 21:39 View session

Copilot AI reviewed Sep 10, 2026

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Distroless builds: Lua, Perl and Php Distroless Builds - #460

Distroless builds: Lua, Perl and Php Distroless Builds#460
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		If a request is not a HEAD method, then reply with "Hello world!"

		Usage: lua examples/server_hello.lua [<port>]

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