build: build and publish image nightly

Removes need to update toolchain for every action step

.forgejo/workflows/build-image.yml

@@ -0,0 +1,18 @@
+on:
+  schedule:
+    - cron: '30 1 * * *'
+  workflow_dispatch:
+
+jobs:
+  build:
+    runs-on: docker
+
+    steps:
+        - name: Checkout
+          uses: actions/checkoutv4
+
+        - name: Build
+          run: docker build . -t git.kemitix.net/kemitix/rust:latest
+
+        - name: Publish
+          run: docker push git.kemitix.net/kemitix/rust:latest

Dockerfile

@@ -1,5 +1,7 @@
 FROM docker.io/rust:1.84.0-slim-bookworm
 
+LABEL org.opencontainers.image.source=https://git.kemitix.net/kemitix/rust
+
 # nodejs - runtime used by forgejo/github actions
 # curl - to download cargo-binstall
 # clang-16 & mold - faster linkers for rust
@@ -25,6 +27,13 @@ RUN cargo binstall -y \
   cargo-mutants@25.0 \
   release-plz@0.3
 
+COPY update.sh /
+
+# should be a no-op if the FROM line is up-to-date
+RUN /update.sh stable 
+
+RUN /update.sh nightly
+
 COPY entrypoint.sh /
 
 RUN git config --global user.email "action@git.kemitix.net" && \

entrypoint.sh

@@ -26,11 +26,6 @@ if [[ "${ARGS[0]}" == v1* ]]; then
 fi
 echo "Selected toolchain: ${TOOLCHAIN}"
 
-echo ">>> Update toolchain"
-rustup update "${TOOLCHAIN}"
-echo ">>> Install rustfmt and clippy"
-rustup component add --toolchain "${TOOLCHAIN}" rustfmt clippy
-
 if test "${ARGS[0]}" == "cargo";then
   PRE_COMMAND="cargo +${TOOLCHAIN} "
 else

update.sh

@@ -0,0 +1,32 @@
+#!/usr/bin/env bash
+
+set -e
+
+echo "INPUT_ARGS: ${INPUT_ARGS}"
+
+# split input into an array
+read -ra ARGS <<<"${INPUT_ARGS}"
+
+# default toolchain
+TOOLCHAIN="stable"
+echo "Default toolchain: ${TOOLCHAIN}"
+
+# if first parameter is 'nightly'...
+if test "${ARGS[0]}" == "nightly"; then
+  TOOLCHAIN="nightly"
+  ARGS=("${ARGS[@]:1}")
+fi
+if test "${ARGS[0]}" == "stable"; then
+  TOOLCHAIN="stable" # redundant as this is the default
+  ARGS=("${ARGS[@]:1}")
+fi
+if [[ "${ARGS[0]}" == v1* ]]; then
+  TOOLCHAIN="${ARGS[0]:1}"
+  ARGS=("${ARGS[@]:1}")
+fi
+echo "Selected toolchain: ${TOOLCHAIN}"
+
+echo ">>> Update toolchain"
+rustup update "${TOOLCHAIN}"
+echo ">>> Install rustfmt and clippy"
+rustup component add --toolchain "${TOOLCHAIN}" rustfmt clippy