From b1e766fe8f74c2c0895adcfd8d21bd5c565a6f7a Mon Sep 17 00:00:00 2001
From: Dave Rolsky <autarch@urth.org>
Date: Sat, 22 Jul 2023 09:43:41 -0500
Subject: [PATCH] Add caching of the installed cross binary

---
 Changes.md                        |  6 ++++++
 action.yml                        | 27 ++++++++++++++++++++++++---
 determine-latest-cross-version.sh | 11 +++++++++++
 install-cross-nix.sh              |  4 +++-
 set-build-command.sh              |  5 +++--
 set-cross-dir.sh                  |  4 ++++
 6 files changed, 51 insertions(+), 6 deletions(-)
 create mode 100755 determine-latest-cross-version.sh
 create mode 100755 set-cross-dir.sh

diff --git a/Changes.md b/Changes.md
index 432ba8e..94587ae 100644
--- a/Changes.md
+++ b/Changes.md
@@ -1,3 +1,9 @@
+## 0.0.8
+
+- For builds that need the `cross` binary, this binary is now cached. A cache
+  hit saves about 20 seconds in my tests. Suggested by @timon-schelling. GH
+  #4.
+
 ## 0.0.7 - 2023-04-21
 
 - The toolchain argument was (probably) not being respected with cross builds,
diff --git a/action.yml b/action.yml
index 45b38e0..9389b96 100644
--- a/action.yml
+++ b/action.yml
@@ -44,16 +44,37 @@ runs:
       with:
         targets: ${{ inputs.target }}
         toolchain: ${{ inputs.toolchain }}
+    - name: Determine latest cross version
+      id: determine-latest-cross-version
+      shell: bash
+      run: determine-latest-cross-version.sh
+      env:
+        GITHUB_TOKEN: ${{ inputs.GITHUB_TOKEN }}
+      if: ${{ steps.determine-cross-compile.outputs.needs-cross == 'true' }}
+    # We need to accesss this in both this YAML config and shell scripts. It
+    # doesn't seem like using ${{ env.RUNNER_TEMP }} works in the YAML config.
+    - name: Set directory for installing cross
+      id: set-cross-dir
+      shell: bash
+      run: set-cross-dir.sh
+      if: ${{ steps.determine-cross-compile.outputs.needs-cross == 'true' }}
+    - name: Cache cross
+      id: cache-cross
+      uses: actions/cache@v3
+      with:
+        path: ${{ steps.set-cross-dir.outputs.cross-dir }}/cross
+        key: ${{ runner.os }}-${{ steps.determine-latest-cross-version.outputs.cross-version }}
+      if: ${{ steps.determine-cross-compile.outputs.needs-cross == 'true' }}
     - name: Install cross if cross-compiling (*nix)
       shell: bash
-      run: install-cross-nix.sh
-      if: ${{ steps.determine-cross-compile.outputs.needs-cross == 'true' }}
+      run: install-cross-nix.sh ${{ steps.set-cross-dir.outputs.cross-dir }}
+      if: ${{ steps.determine-cross-compile.outputs.needs-cross == 'true' && steps.cache-cross.outputs.cache-hit != 'true' }}
       env:
         GITHUB_TOKEN: ${{ inputs.GITHUB_TOKEN }}
     - name: Set build command
       id: set-build-command
       shell: bash
-      run: set-build-command.sh
+      run: set-build-command.sh ${{ steps.set-cross-dir.outputs.cross-dir }}
     - name: Run tests (*nix)
       shell: bash
       run: |
diff --git a/determine-latest-cross-version.sh b/determine-latest-cross-version.sh
new file mode 100755
index 0000000..90278de
--- /dev/null
+++ b/determine-latest-cross-version.sh
@@ -0,0 +1,11 @@
+set -e
+set -x
+set -o pipefail
+
+JSON=$( curl \
+            --request GET \
+            --header "Authorization: Bearer $GITHUB_TOKEN" \
+            https://api.github.com/repos/cross-rs/cross/releases/latest )
+VERSION=$( echo "$JSON" | jq -r ".tag_name")
+
+echo "cross-version=$VERSION" >> $GITHUB_OUTPUT
diff --git a/install-cross-nix.sh b/install-cross-nix.sh
index d7f52c6..fb1dc86 100755
--- a/install-cross-nix.sh
+++ b/install-cross-nix.sh
@@ -1,7 +1,9 @@
 set -e
 set -x
+set -o pipefail
 
-cd "$RUNNER_TEMP"
+CROSS_DIR="$1"
+cd "$CROSS_DIR"
 export TARGET=.
 curl --silent --location \
      https://raw.githubusercontent.com/houseabsolute/ubi/master/bootstrap/bootstrap-ubi.sh |
diff --git a/set-build-command.sh b/set-build-command.sh
index 9b471a6..953cb6c 100755
--- a/set-build-command.sh
+++ b/set-build-command.sh
@@ -1,8 +1,9 @@
 set -e
 set -x
 
-if [ -f "$RUNNER_TEMP/cross" ]; then
-    echo "build-command=$RUNNER_TEMP/cross" >> $GITHUB_OUTPUT
+CROSS_DIR="$1"
+if [ -f "$CROSS_DIR/cross" ]; then
+    echo "build-command=$CROSS_DIR/cross" >> $GITHUB_OUTPUT
 else
     echo "build-command=cargo" >> $GITHUB_OUTPUT
 fi
diff --git a/set-cross-dir.sh b/set-cross-dir.sh
new file mode 100755
index 0000000..f67a0af
--- /dev/null
+++ b/set-cross-dir.sh
@@ -0,0 +1,4 @@
+set -e
+set -x
+
+echo "cross-dir=$RUNNER_TEMP" >> $GITHUB_OUTPUT