From 4cd7fc4c833146910cd7f949cbef7aa96238b6bf Mon Sep 17 00:00:00 2001
From: Razvan Deaconescu <razvand@unikraft.io>
Date: Wed, 15 Nov 2023 00:17:22 +0200
Subject: [PATCH] feat(library): Add support for Caddy

Introduce Caddy bincompat run. Build Caddy as static PIE using a
Dockerfile, inspired by Caddy's own Docker setup. Use `xcaddy` to build.
The build uses binary compatibility mode (i.e. the `base` image).

Add:

* `Kraftfile`: build / run rules, including pulling the `base` image
* `Dockerfile`: base filesystem, with binary and libraries
* `README.md`: document how to use
* `Caddyfile`: Caddy configuration file

Signed-off-by: Razvan Deaconescu <razvand@unikraft.io>
---
 library/caddy/2.7/Caddyfile  |  3 +++
 library/caddy/2.7/Dockerfile | 34 ++++++++++++++++++++++++++++++++++
 library/caddy/2.7/Kraftfile  |  7 +++++++
 library/caddy/2.7/README.md  | 15 +++++++++++++++
 4 files changed, 59 insertions(+)
 create mode 100644 library/caddy/2.7/Caddyfile
 create mode 100644 library/caddy/2.7/Dockerfile
 create mode 100644 library/caddy/2.7/Kraftfile
 create mode 100644 library/caddy/2.7/README.md

diff --git a/library/caddy/2.7/Caddyfile b/library/caddy/2.7/Caddyfile
new file mode 100644
index 00000000..44b4ae8a
--- /dev/null
+++ b/library/caddy/2.7/Caddyfile
@@ -0,0 +1,3 @@
+:2015
+
+respond "Hello, world!"
diff --git a/library/caddy/2.7/Dockerfile b/library/caddy/2.7/Dockerfile
new file mode 100644
index 00000000..dcab420f
--- /dev/null
+++ b/library/caddy/2.7/Dockerfile
@@ -0,0 +1,34 @@
+FROM --platform=linux/x86_64 golang:1.21.4-bookworm AS build
+
+# Inspired from: https://github.com/caddyserver/caddy-docker/blob/master/2.7/builder/Dockerfile
+
+RUN set -xe; apt-get update ; \
+	apt-get install -y --no-install-recommends \
+	ca-certificates \
+	git \
+	libcap2-bin \
+	;
+
+ENV XCADDY_VERSION v0.3.5
+# Configures xcaddy to build with this version of Caddy
+ENV CADDY_VERSION v2.7.5
+# Configures xcaddy to not clean up post-build (unnecessary in a container)
+ENV XCADDY_SKIP_CLEANUP 1
+# Sets capabilities for output caddy binary to be able to bind to privileged ports
+ENV XCADDY_SETCAP 1
+
+RUN set -xe; \
+	wget -O /tmp/xcaddy.tar.gz "https://github.com/caddyserver/xcaddy/releases/download/v0.3.5/xcaddy_0.3.5_linux_amd64.tar.gz"; \
+	tar x -z -f /tmp/xcaddy.tar.gz -C /usr/bin xcaddy; \
+	rm -f /tmp/xcaddy.tar.gz; \
+	chmod +x /usr/bin/xcaddy;
+
+ENV CGO_ENABLED=1
+ENV XCADDY_GO_BUILD_FLAGS "-buildmode=pie -ldflags '-linkmode external -extldflags -static-pie'"
+
+RUN /usr/bin/xcaddy build
+
+FROM scratch
+
+COPY --from=build /go/caddy /caddy
+COPY Caddyfile /Caddyfile
diff --git a/library/caddy/2.7/Kraftfile b/library/caddy/2.7/Kraftfile
new file mode 100644
index 00000000..1a505fe0
--- /dev/null
+++ b/library/caddy/2.7/Kraftfile
@@ -0,0 +1,7 @@
+spec: v0.6
+
+runtime: unikraft.org/base:latest
+
+rootfs: ./Dockerfile
+
+cmd: ["/caddy", "run"]
diff --git a/library/caddy/2.7/README.md b/library/caddy/2.7/README.md
new file mode 100644
index 00000000..94bc499c
--- /dev/null
+++ b/library/caddy/2.7/README.md
@@ -0,0 +1,15 @@
+# Caddy 2.7
+
+This directory contains the definition for the `unikraft.org/caddy:2.7` image.
+
+To run this image, [install Unikraft's companion command-line toolchain `kraft`](https://unikraft.org/docs/cli) and then you can run:
+
+```
+kraft run unikraft.org/caddy:2.7 -p 2015:2015
+```
+
+Once executed, it will open port `2015` and wait for connections, and can be queried.
+
+## See also
+
+- [How to run unikernels locally in Unikraft's Documentation](https://unikraft.org/docs/cli/running).