Add pkg-precompile.jl script

.github/workflows/CI.yaml

@@ -0,0 +1,67 @@
+---
+name: CI
+on:
+  pull_request:
+    paths:
+      - "pkg-precompile.jl"
+      - "test/**"
+      - ".github/workflows/CI.yaml"
+  push:
+    branches:
+      - main
+    tags: ["*"]
+
+jobs:
+  version:
+    name: Resolve Julia Versions
+    # These permissions are needed to:
+    # - Checkout the Git repository (`contents: read`)
+    permissions:
+      contents: read
+    runs-on: ubuntu-latest
+    outputs:
+      json: ${{ steps.julia-version.outputs.resolved-json }}
+    steps:
+      - uses: actions/checkout@v4 # Needed for "min" to access the Project.toml
+      - uses: julia-actions/[email protected]
+        id: julia-version
+        with:
+          versions: |
+            - min     # Oldest supported version
+            - lts     # Long-Term Stable
+            - 1.10.0  # Earliest 1.10 release 
+            - 1.10    # Latest 1.10 release
+            - 1.11.0  # Earliest 1.11 release
+            - 1.11    # Latest 1.11 release 
+            - 1.12-nightly
+          project: test
+          if-missing: error
+
+  test:
+    name: Julia ${{ matrix.version }} - ${{ matrix.os }}
+    needs: version
+    # These permissions are needed to:
+    # - Delete old caches: https://github.com/julia-actions/cache#usage
+    permissions:
+      actions: write
+      contents: read
+    runs-on: ${{ matrix.os }}
+    strategy:
+      fail-fast: false
+      matrix:
+        version: ${{ fromJSON(needs.version.outputs.json) }}
+        os:
+          - ubuntu-24.04
+    steps:
+      - uses: actions/checkout@v4
+      - uses: julia-actions/setup-julia@v2
+        with:
+          version: ${{ matrix.version }}
+      - uses: julia-actions/cache@v1
+      - name: Instantiate
+        shell: julia --color=yes --project=test {0}
+        run: |
+          using Pkg
+          Pkg.instantiate()
+      - name: Test
+        run: julia --color=yes --project=test test/runtests.jl

.gitignore

@@ -0,0 +1,2 @@
+test/Manifest.toml
+test/*/Manifest.toml

README.md

@@ -1 +1,56 @@
-# julia-container-scripts
+# julia-container-scripts
+
+Provides useful scripts for creating Julia container images.
+
+## `pkg-precompile.jl`
+
+The `pkg-precompile.jl` script supports creating Julia precompilation cache (`.ji`) files in a [build container cache mount](https://docs.docker.com/reference/dockerfile/#run---mounttypecache). By utilizing the build cache mount we can reuse precompilation files between builds which signficantly improves reduces Docker build times. A complete `Dockerfile` example can be seen below:
+
+```Dockerfile
+ARG JULIA_VERSION=1.11.4
+FROM julia:${JULIA_VERSION}-bookworm AS julia-base
+
+# Disable automatic package precompilation. We'll control when packages are precompiled.
+ENV JULIA_PKG_PRECOMPILE_AUTO="0"
+
+# Add registries required for instantiation
+RUN julia --color=yes -e 'using Pkg; Pkg.Registry.add("General")'
+
+# Limit Docker layer invalidation by only copying the Project.toml/Manifest.toml files.
+ENV JULIA_PROJECT="/project"
+COPY Project.toml *Manifest.toml ${JULIA_PROJECT}/
+
+# TODO: Delete this optional statement if your Project.toml does not include the field
+# "name" or you don't care about supporting the Julia versions listed below.
+#
+# Julia 1.10.0 - 1.10.6 and 1.11.0 require this source file to be present when
+# instantiating a named Julia project.
+RUN curl -fsSLO https://raw.githubusercontent.com/beacon-biosignals/julia-container-scripts/refs/tags/v1/gen-pkg-src.jl && \
+    chmod +x gen-pkg-src.jl && \
+    ./gen-pkg-src.jl && \
+    rm gen-pkg-src.jl
+
+# Instantiate the Julia project environment and avoid precompiling. Ensure we perform a
+# registry update here as changes to the Project.toml/Manifest.toml do not invalidate the
+# Docker layer which added the registry.
+RUN julia --color=yes -e 'using Pkg; Pkg.Registry.update(); Pkg.instantiate(); Pkg.build()'
+
+# TODO: Delete this optional statement if you don't care about Julia 1.10 support or combine
+# this statement with instantiate above to avoid bloating image size.
+#
+# Use a fixed modification time for all files in "packages" to avoid unnecessary precompile
+# cache invalidation on Julia 1.10.
+RUN julia -e 'VERSION < v"1.11" || exit(1)' && \
+    find "$(julia -e 'println(DEPOT_PATH[1])')/packages" -exec touch -m -t 197001010000 {} \;
+
+# Precompile project dependencies using a Docker cache mount which persists between builds.
+RUN --mount=type=cache,id=julia-depot,sharing=shared,target=/mnt/julia-depot \
+    curl -fsSLO https://raw.githubusercontent.com/beacon-biosignals/julia-container-scripts/refs/tags/v1/pkg-precompile.jl &&
+    chmod +x pkg-precompile.jl && \
+    ./pkg-precompile.jl "/mnt/julia-depot" && \
+    rm pkg-precompile.jl
+
+# Copy files necessary to load package and perform the first initialization.
+COPY src ${JULIA_PROJECT}/src
+RUN julia -e 'using Pkg; name = Pkg.Types.EnvCache().project.name; Pkg.precompile(name; timing=true); Base.require(Main, Symbol(name))'
+```

gen-pkg-src.jl

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+#!/usr/bin/env -S julia --color=yes
+
+using Pkg
+
+env = Pkg.Types.EnvCache()
+project_file = env.project_file
+project_name = env.project.name
+
+if project_name !== nothing
+    entry_file = joinpath(dirname(project_file), "src", "$(project_name).jl")
+
+    if !isfile(entry_file)
+        mkdir(dirname(entry_file))
+
+        # Define an empty module to avoid warnings such as:
+        # ```
+        # WARNING: --output requested, but no modules defined during run
+        # ```
+        open(entry_file, "w") do io
+            println(io, "module $(project_name)")
+            println(io, "end")
+        end
+    end
+else
+    @warn "Julia project is unnamed and does not require an entry source file"
+end