Add a Salesforce Functions builder variant

.github/workflows/build-test-publish.yml

@@ -25,7 +25,7 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        builder: ["buildpacks-20", "builder-classic-22", "builder-22"]
+        builder: ["buildpacks-20", "builder-classic-22", "builder-22", "salesforce-functions"]
     steps:
       - name: Checkout
         uses: actions/checkout@v3
@@ -39,9 +39,11 @@ jobs:
       # We manually compress the archive rather than relying upon actions/cache's compression, since
       # it ends up being faster both in this job and also later when the images are consumed.
       - name: Export Docker images from the Docker daemon
-        env:
-          BUILDER: ${{ matrix.builder }}
-        run: docker save ${{ matrix.builder }} heroku/heroku:${BUILDER##*-}-cnb | zstd -T0 --long=31 -o images.tar.zst
+        # Using sed rather than yq until this yq bug is fixed:
+        # https://github.com/mikefarah/yq/issues/1758
+        run: |
+          RUN_IMAGE_TAG=$(sed --quiet --regexp-extended --expression 's/run-image\s*=\s*"(.+)"/\1/p' ${{ matrix.builder }}/builder.toml)
+          docker save ${{ matrix.builder }} ${RUN_IMAGE_TAG} | zstd -T0 --long=31 -o images.tar.zst
       # We use a cache here rather than artifacts because it's 4x faster and we
       # don't need the builder archive outside of this workflow run anyway.
       - name: Save Docker images to the cache
@@ -102,7 +104,7 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        builder: ["builder-22"]
+        builder: ["builder-22", "salesforce-functions"]
         language: ["java", "javascript", "typescript"]
     steps:
       - name: Checkout
@@ -152,6 +154,8 @@ jobs:
           - builder: builder-22
             tag_public: heroku/builder:22
             tag_private: heroku-22:builder
+          - builder: salesforce-functions
+            tag_private: heroku-22:builder-functions
     steps:
       - name: Restore Docker images from the cache
         uses: actions/cache/restore@v3

Makefile

@@ -6,7 +6,9 @@ build:
 	@pack builder create heroku/buildpacks:20 --config buildpacks-20/builder.toml --pull-policy always
 	@pack builder create heroku/builder:22 --config builder-22/builder.toml --pull-policy always
 	@pack builder create heroku/builder-classic:22 --config builder-classic-22/builder.toml --pull-policy always
+	@pack builder create salesforce-functions --config salesforce-functions/builder.toml --pull-policy always
 
+# The salesforce-functions image isn't published to Docker Hub, so is intentionally absent here.
 publish: build
 	@docker push heroku/buildpacks:20
 	@docker push heroku/builder:22

salesforce-functions/builder.toml

@@ -0,0 +1,27 @@
+description = "Internal builder image for Salesforce Functions"
+
+[stack]
+id = "heroku-22"
+build-image = "heroku/heroku:22-cnb-build"
+run-image = "heroku/heroku:22-cnb"
+
+[lifecycle]
+version = "0.17.1"
+
+[[buildpacks]]
+  id = "heroku/java-function"
+  uri = "docker://docker.io/heroku/buildpack-java-function@sha256:4cbe8d4984f70fc63e6b0fcea1b904d4246d90bbe0b9cc10ba8b73c98eda3b00"
+
+[[buildpacks]]
+  id = "heroku/nodejs-function"
+  uri = "docker://docker.io/heroku/buildpack-nodejs-function@sha256:69d61df4e1805055fcf2911e75f5fed59b02292f2bda7c78b6f891e8d8cd00f3"
+
+[[order]]
+  [[order.group]]
+    id = "heroku/nodejs-function"
+    version = "1.1.6"
+
+[[order]]
+  [[order.group]]
+    id = "heroku/java-function"
+    version = "3.2.0"