From ee169b2fdded535c80917483e9759261bef9eb8b Mon Sep 17 00:00:00 2001
From: Travis Shivers <ttshivers@gmail.com>
Date: Thu, 24 Sep 2020 21:58:22 -0500
Subject: [PATCH] ci: use single dynamic build-test action

Add a GitHub action that dynamically generates the matrix of Dockerfiles
to test based on what files have changed. This avoids having to have
generated workflows for each version x variant combo.

It looks for any changed Dockerfiles, or docker-entrypoint.sh. If any of
the testing files are changed, it will test all Dockerfiles
---
 .github/workflows/10-alpine3.10.yml   | 24 -------
 .github/workflows/10-alpine3.11.yml   | 24 -------
 .github/workflows/10-alpine3.9.yml    | 24 -------
 .github/workflows/10-buster-slim.yml  | 24 -------
 .github/workflows/10-buster.yml       | 24 -------
 .github/workflows/10-stretch-slim.yml | 24 -------
 .github/workflows/10-stretch.yml      | 24 -------
 .github/workflows/12-alpine3.10.yml   | 24 -------
 .github/workflows/12-alpine3.11.yml   | 24 -------
 .github/workflows/12-alpine3.12.yml   | 24 -------
 .github/workflows/12-alpine3.9.yml    | 24 -------
 .github/workflows/12-buster-slim.yml  | 24 -------
 .github/workflows/12-buster.yml       | 24 -------
 .github/workflows/12-stretch-slim.yml | 24 -------
 .github/workflows/12-stretch.yml      | 24 -------
 .github/workflows/14-alpine3.10.yml   | 24 -------
 .github/workflows/14-alpine3.11.yml   | 24 -------
 .github/workflows/14-alpine3.12.yml   | 24 -------
 .github/workflows/14-buster-slim.yml  | 24 -------
 .github/workflows/14-buster.yml       | 24 -------
 .github/workflows/14-stretch-slim.yml | 24 -------
 .github/workflows/14-stretch.yml      | 24 -------
 .github/workflows/build-test.yml      | 89 +++++++++++++++++++++++++
 .github/workflows/dockerfiles.yml     | 11 ----
 genMatrix.js                          | 80 +++++++++++++++++++++++
 test-build.sh                         | 93 ---------------------------
 test-image.bats                       | 17 -----
 update.sh                             | 49 +-------------
 28 files changed, 171 insertions(+), 696 deletions(-)
 delete mode 100644 .github/workflows/10-alpine3.10.yml
 delete mode 100644 .github/workflows/10-alpine3.11.yml
 delete mode 100644 .github/workflows/10-alpine3.9.yml
 delete mode 100644 .github/workflows/10-buster-slim.yml
 delete mode 100644 .github/workflows/10-buster.yml
 delete mode 100644 .github/workflows/10-stretch-slim.yml
 delete mode 100644 .github/workflows/10-stretch.yml
 delete mode 100644 .github/workflows/12-alpine3.10.yml
 delete mode 100644 .github/workflows/12-alpine3.11.yml
 delete mode 100644 .github/workflows/12-alpine3.12.yml
 delete mode 100644 .github/workflows/12-alpine3.9.yml
 delete mode 100644 .github/workflows/12-buster-slim.yml
 delete mode 100644 .github/workflows/12-buster.yml
 delete mode 100644 .github/workflows/12-stretch-slim.yml
 delete mode 100644 .github/workflows/12-stretch.yml
 delete mode 100644 .github/workflows/14-alpine3.10.yml
 delete mode 100644 .github/workflows/14-alpine3.11.yml
 delete mode 100644 .github/workflows/14-alpine3.12.yml
 delete mode 100644 .github/workflows/14-buster-slim.yml
 delete mode 100644 .github/workflows/14-buster.yml
 delete mode 100644 .github/workflows/14-stretch-slim.yml
 delete mode 100644 .github/workflows/14-stretch.yml
 create mode 100644 .github/workflows/build-test.yml
 delete mode 100644 .github/workflows/dockerfiles.yml
 create mode 100644 genMatrix.js
 delete mode 100755 test-build.sh
 delete mode 100755 test-image.bats

diff --git a/.github/workflows/10-alpine3.10.yml b/.github/workflows/10-alpine3.10.yml
deleted file mode 100644
index 1e27cc11f..000000000
--- a/.github/workflows/10-alpine3.10.yml
+++ /dev/null
@@ -1,24 +0,0 @@
-name: 10 on alpine3.10
-
-on:
-  push:
-    paths:
-      - functions.sh
-      - test-build.sh
-      - test-image.bats
-      - 10/alpine3.10/Dockerfile
-  pull_request:
-    paths:
-      - functions.sh
-      - test-build.sh
-      - test-image.bats
-      - 10/alpine3.10/Dockerfile
-
-jobs:
-  build:
-    name: 10 on alpine3.10
-    runs-on: ubuntu-latest
-    steps:
-      - uses: actions/checkout@v2
-      - run: sudo apt-get install bats
-      - run: ./test-build.sh 10 alpine3.10
diff --git a/.github/workflows/10-alpine3.11.yml b/.github/workflows/10-alpine3.11.yml
deleted file mode 100644
index e7f459afe..000000000
--- a/.github/workflows/10-alpine3.11.yml
+++ /dev/null
@@ -1,24 +0,0 @@
-name: 10 on alpine3.11
-
-on:
-  push:
-    paths:
-      - functions.sh
-      - test-build.sh
-      - test-image.bats
-      - 10/alpine3.11/Dockerfile
-  pull_request:
-    paths:
-      - functions.sh
-      - test-build.sh
-      - test-image.bats
-      - 10/alpine3.11/Dockerfile
-
-jobs:
-  build:
-    name: 10 on alpine3.11
-    runs-on: ubuntu-latest
-    steps:
-      - uses: actions/checkout@v2
-      - run: sudo apt-get install bats
-      - run: ./test-build.sh 10 alpine3.11
diff --git a/.github/workflows/10-alpine3.9.yml b/.github/workflows/10-alpine3.9.yml
deleted file mode 100644
index cfc60915a..000000000
--- a/.github/workflows/10-alpine3.9.yml
+++ /dev/null
@@ -1,24 +0,0 @@
-name: 10 on alpine3.9
-
-on:
-  push:
-    paths:
-      - functions.sh
-      - test-build.sh
-      - test-image.bats
-      - 10/alpine3.9/Dockerfile
-  pull_request:
-    paths:
-      - functions.sh
-      - test-build.sh
-      - test-image.bats
-      - 10/alpine3.9/Dockerfile
-
-jobs:
-  build:
-    name: 10 on alpine3.9
-    runs-on: ubuntu-latest
-    steps:
-      - uses: actions/checkout@v2
-      - run: sudo apt-get install bats
-      - run: ./test-build.sh 10 alpine3.9
diff --git a/.github/workflows/10-buster-slim.yml b/.github/workflows/10-buster-slim.yml
deleted file mode 100644
index 7d1b53e9a..000000000
--- a/.github/workflows/10-buster-slim.yml
+++ /dev/null
@@ -1,24 +0,0 @@
-name: 10 on buster-slim
-
-on:
-  push:
-    paths:
-      - functions.sh
-      - test-build.sh
-      - test-image.bats
-      - 10/buster-slim/Dockerfile
-  pull_request:
-    paths:
-      - functions.sh
-      - test-build.sh
-      - test-image.bats
-      - 10/buster-slim/Dockerfile
-
-jobs:
-  build:
-    name: 10 on buster-slim
-    runs-on: ubuntu-latest
-    steps:
-      - uses: actions/checkout@v2
-      - run: sudo apt-get install bats
-      - run: ./test-build.sh 10 buster-slim
diff --git a/.github/workflows/10-buster.yml b/.github/workflows/10-buster.yml
deleted file mode 100644
index 648f5f7b9..000000000
--- a/.github/workflows/10-buster.yml
+++ /dev/null
@@ -1,24 +0,0 @@
-name: 10 on buster
-
-on:
-  push:
-    paths:
-      - functions.sh
-      - test-build.sh
-      - test-image.bats
-      - 10/buster/Dockerfile
-  pull_request:
-    paths:
-      - functions.sh
-      - test-build.sh
-      - test-image.bats
-      - 10/buster/Dockerfile
-
-jobs:
-  build:
-    name: 10 on buster
-    runs-on: ubuntu-latest
-    steps:
-      - uses: actions/checkout@v2
-      - run: sudo apt-get install bats
-      - run: ./test-build.sh 10 buster
diff --git a/.github/workflows/10-stretch-slim.yml b/.github/workflows/10-stretch-slim.yml
deleted file mode 100644
index 846ec74de..000000000
--- a/.github/workflows/10-stretch-slim.yml
+++ /dev/null
@@ -1,24 +0,0 @@
-name: 10 on stretch-slim
-
-on:
-  push:
-    paths:
-      - functions.sh
-      - test-build.sh
-      - test-image.bats
-      - 10/stretch-slim/Dockerfile
-  pull_request:
-    paths:
-      - functions.sh
-      - test-build.sh
-      - test-image.bats
-      - 10/stretch-slim/Dockerfile
-
-jobs:
-  build:
-    name: 10 on stretch-slim
-    runs-on: ubuntu-latest
-    steps:
-      - uses: actions/checkout@v2
-      - run: sudo apt-get install bats
-      - run: ./test-build.sh 10 stretch-slim
diff --git a/.github/workflows/10-stretch.yml b/.github/workflows/10-stretch.yml
deleted file mode 100644
index 7a9dc1b22..000000000
--- a/.github/workflows/10-stretch.yml
+++ /dev/null
@@ -1,24 +0,0 @@
-name: 10 on stretch
-
-on:
-  push:
-    paths:
-      - functions.sh
-      - test-build.sh
-      - test-image.bats
-      - 10/stretch/Dockerfile
-  pull_request:
-    paths:
-      - functions.sh
-      - test-build.sh
-      - test-image.bats
-      - 10/stretch/Dockerfile
-
-jobs:
-  build:
-    name: 10 on stretch
-    runs-on: ubuntu-latest
-    steps:
-      - uses: actions/checkout@v2
-      - run: sudo apt-get install bats
-      - run: ./test-build.sh 10 stretch
diff --git a/.github/workflows/12-alpine3.10.yml b/.github/workflows/12-alpine3.10.yml
deleted file mode 100644
index e81565fe7..000000000
--- a/.github/workflows/12-alpine3.10.yml
+++ /dev/null
@@ -1,24 +0,0 @@
-name: 12 on alpine3.10
-
-on:
-  push:
-    paths:
-      - functions.sh
-      - test-build.sh
-      - test-image.bats
-      - 12/alpine3.10/Dockerfile
-  pull_request:
-    paths:
-      - functions.sh
-      - test-build.sh
-      - test-image.bats
-      - 12/alpine3.10/Dockerfile
-
-jobs:
-  build:
-    name: 12 on alpine3.10
-    runs-on: ubuntu-latest
-    steps:
-      - uses: actions/checkout@v2
-      - run: sudo apt-get install bats
-      - run: ./test-build.sh 12 alpine3.10
diff --git a/.github/workflows/12-alpine3.11.yml b/.github/workflows/12-alpine3.11.yml
deleted file mode 100644
index 531a09680..000000000
--- a/.github/workflows/12-alpine3.11.yml
+++ /dev/null
@@ -1,24 +0,0 @@
-name: 12 on alpine3.11
-
-on:
-  push:
-    paths:
-      - functions.sh
-      - test-build.sh
-      - test-image.bats
-      - 12/alpine3.11/Dockerfile
-  pull_request:
-    paths:
-      - functions.sh
-      - test-build.sh
-      - test-image.bats
-      - 12/alpine3.11/Dockerfile
-
-jobs:
-  build:
-    name: 12 on alpine3.11
-    runs-on: ubuntu-latest
-    steps:
-      - uses: actions/checkout@v2
-      - run: sudo apt-get install bats
-      - run: ./test-build.sh 12 alpine3.11
diff --git a/.github/workflows/12-alpine3.12.yml b/.github/workflows/12-alpine3.12.yml
deleted file mode 100644
index f18fc554e..000000000
--- a/.github/workflows/12-alpine3.12.yml
+++ /dev/null
@@ -1,24 +0,0 @@
-name: 12 on alpine3.12
-
-on:
-  push:
-    paths:
-      - functions.sh
-      - test-build.sh
-      - test-image.bats
-      - 12/alpine3.12/Dockerfile
-  pull_request:
-    paths:
-      - functions.sh
-      - test-build.sh
-      - test-image.bats
-      - 12/alpine3.12/Dockerfile
-
-jobs:
-  build:
-    name: 12 on alpine3.12
-    runs-on: ubuntu-latest
-    steps:
-      - uses: actions/checkout@v2
-      - run: sudo apt-get install bats
-      - run: ./test-build.sh 12 alpine3.12
diff --git a/.github/workflows/12-alpine3.9.yml b/.github/workflows/12-alpine3.9.yml
deleted file mode 100644
index 385ff52a2..000000000
--- a/.github/workflows/12-alpine3.9.yml
+++ /dev/null
@@ -1,24 +0,0 @@
-name: 12 on alpine3.9
-
-on:
-  push:
-    paths:
-      - functions.sh
-      - test-build.sh
-      - test-image.bats
-      - 12/alpine3.9/Dockerfile
-  pull_request:
-    paths:
-      - functions.sh
-      - test-build.sh
-      - test-image.bats
-      - 12/alpine3.9/Dockerfile
-
-jobs:
-  build:
-    name: 12 on alpine3.9
-    runs-on: ubuntu-latest
-    steps:
-      - uses: actions/checkout@v2
-      - run: sudo apt-get install bats
-      - run: ./test-build.sh 12 alpine3.9
diff --git a/.github/workflows/12-buster-slim.yml b/.github/workflows/12-buster-slim.yml
deleted file mode 100644
index 04f8e8b11..000000000
--- a/.github/workflows/12-buster-slim.yml
+++ /dev/null
@@ -1,24 +0,0 @@
-name: 12 on buster-slim
-
-on:
-  push:
-    paths:
-      - functions.sh
-      - test-build.sh
-      - test-image.bats
-      - 12/buster-slim/Dockerfile
-  pull_request:
-    paths:
-      - functions.sh
-      - test-build.sh
-      - test-image.bats
-      - 12/buster-slim/Dockerfile
-
-jobs:
-  build:
-    name: 12 on buster-slim
-    runs-on: ubuntu-latest
-    steps:
-      - uses: actions/checkout@v2
-      - run: sudo apt-get install bats
-      - run: ./test-build.sh 12 buster-slim
diff --git a/.github/workflows/12-buster.yml b/.github/workflows/12-buster.yml
deleted file mode 100644
index 0b16ee6a9..000000000
--- a/.github/workflows/12-buster.yml
+++ /dev/null
@@ -1,24 +0,0 @@
-name: 12 on buster
-
-on:
-  push:
-    paths:
-      - functions.sh
-      - test-build.sh
-      - test-image.bats
-      - 12/buster/Dockerfile
-  pull_request:
-    paths:
-      - functions.sh
-      - test-build.sh
-      - test-image.bats
-      - 12/buster/Dockerfile
-
-jobs:
-  build:
-    name: 12 on buster
-    runs-on: ubuntu-latest
-    steps:
-      - uses: actions/checkout@v2
-      - run: sudo apt-get install bats
-      - run: ./test-build.sh 12 buster
diff --git a/.github/workflows/12-stretch-slim.yml b/.github/workflows/12-stretch-slim.yml
deleted file mode 100644
index 608160eeb..000000000
--- a/.github/workflows/12-stretch-slim.yml
+++ /dev/null
@@ -1,24 +0,0 @@
-name: 12 on stretch-slim
-
-on:
-  push:
-    paths:
-      - functions.sh
-      - test-build.sh
-      - test-image.bats
-      - 12/stretch-slim/Dockerfile
-  pull_request:
-    paths:
-      - functions.sh
-      - test-build.sh
-      - test-image.bats
-      - 12/stretch-slim/Dockerfile
-
-jobs:
-  build:
-    name: 12 on stretch-slim
-    runs-on: ubuntu-latest
-    steps:
-      - uses: actions/checkout@v2
-      - run: sudo apt-get install bats
-      - run: ./test-build.sh 12 stretch-slim
diff --git a/.github/workflows/12-stretch.yml b/.github/workflows/12-stretch.yml
deleted file mode 100644
index 8019f3e1f..000000000
--- a/.github/workflows/12-stretch.yml
+++ /dev/null
@@ -1,24 +0,0 @@
-name: 12 on stretch
-
-on:
-  push:
-    paths:
-      - functions.sh
-      - test-build.sh
-      - test-image.bats
-      - 12/stretch/Dockerfile
-  pull_request:
-    paths:
-      - functions.sh
-      - test-build.sh
-      - test-image.bats
-      - 12/stretch/Dockerfile
-
-jobs:
-  build:
-    name: 12 on stretch
-    runs-on: ubuntu-latest
-    steps:
-      - uses: actions/checkout@v2
-      - run: sudo apt-get install bats
-      - run: ./test-build.sh 12 stretch
diff --git a/.github/workflows/14-alpine3.10.yml b/.github/workflows/14-alpine3.10.yml
deleted file mode 100644
index e0d04a271..000000000
--- a/.github/workflows/14-alpine3.10.yml
+++ /dev/null
@@ -1,24 +0,0 @@
-name: 14 on alpine3.10
-
-on:
-  push:
-    paths:
-      - functions.sh
-      - test-build.sh
-      - test-image.bats
-      - 14/alpine3.10/Dockerfile
-  pull_request:
-    paths:
-      - functions.sh
-      - test-build.sh
-      - test-image.bats
-      - 14/alpine3.10/Dockerfile
-
-jobs:
-  build:
-    name: 14 on alpine3.10
-    runs-on: ubuntu-latest
-    steps:
-      - uses: actions/checkout@v2
-      - run: sudo apt-get install bats
-      - run: ./test-build.sh 14 alpine3.10
diff --git a/.github/workflows/14-alpine3.11.yml b/.github/workflows/14-alpine3.11.yml
deleted file mode 100644
index c401f9389..000000000
--- a/.github/workflows/14-alpine3.11.yml
+++ /dev/null
@@ -1,24 +0,0 @@
-name: 14 on alpine3.11
-
-on:
-  push:
-    paths:
-      - functions.sh
-      - test-build.sh
-      - test-image.bats
-      - 14/alpine3.11/Dockerfile
-  pull_request:
-    paths:
-      - functions.sh
-      - test-build.sh
-      - test-image.bats
-      - 14/alpine3.11/Dockerfile
-
-jobs:
-  build:
-    name: 14 on alpine3.11
-    runs-on: ubuntu-latest
-    steps:
-      - uses: actions/checkout@v2
-      - run: sudo apt-get install bats
-      - run: ./test-build.sh 14 alpine3.11
diff --git a/.github/workflows/14-alpine3.12.yml b/.github/workflows/14-alpine3.12.yml
deleted file mode 100644
index 3a20d9520..000000000
--- a/.github/workflows/14-alpine3.12.yml
+++ /dev/null
@@ -1,24 +0,0 @@
-name: 14 on alpine3.12
-
-on:
-  push:
-    paths:
-      - functions.sh
-      - test-build.sh
-      - test-image.bats
-      - 14/alpine3.12/Dockerfile
-  pull_request:
-    paths:
-      - functions.sh
-      - test-build.sh
-      - test-image.bats
-      - 14/alpine3.12/Dockerfile
-
-jobs:
-  build:
-    name: 14 on alpine3.12
-    runs-on: ubuntu-latest
-    steps:
-      - uses: actions/checkout@v2
-      - run: sudo apt-get install bats
-      - run: ./test-build.sh 14 alpine3.12
diff --git a/.github/workflows/14-buster-slim.yml b/.github/workflows/14-buster-slim.yml
deleted file mode 100644
index b7d027f93..000000000
--- a/.github/workflows/14-buster-slim.yml
+++ /dev/null
@@ -1,24 +0,0 @@
-name: 14 on buster-slim
-
-on:
-  push:
-    paths:
-      - functions.sh
-      - test-build.sh
-      - test-image.bats
-      - 14/buster-slim/Dockerfile
-  pull_request:
-    paths:
-      - functions.sh
-      - test-build.sh
-      - test-image.bats
-      - 14/buster-slim/Dockerfile
-
-jobs:
-  build:
-    name: 14 on buster-slim
-    runs-on: ubuntu-latest
-    steps:
-      - uses: actions/checkout@v2
-      - run: sudo apt-get install bats
-      - run: ./test-build.sh 14 buster-slim
diff --git a/.github/workflows/14-buster.yml b/.github/workflows/14-buster.yml
deleted file mode 100644
index 4481aadc2..000000000
--- a/.github/workflows/14-buster.yml
+++ /dev/null
@@ -1,24 +0,0 @@
-name: 14 on buster
-
-on:
-  push:
-    paths:
-      - functions.sh
-      - test-build.sh
-      - test-image.bats
-      - 14/buster/Dockerfile
-  pull_request:
-    paths:
-      - functions.sh
-      - test-build.sh
-      - test-image.bats
-      - 14/buster/Dockerfile
-
-jobs:
-  build:
-    name: 14 on buster
-    runs-on: ubuntu-latest
-    steps:
-      - uses: actions/checkout@v2
-      - run: sudo apt-get install bats
-      - run: ./test-build.sh 14 buster
diff --git a/.github/workflows/14-stretch-slim.yml b/.github/workflows/14-stretch-slim.yml
deleted file mode 100644
index d7c68f026..000000000
--- a/.github/workflows/14-stretch-slim.yml
+++ /dev/null
@@ -1,24 +0,0 @@
-name: 14 on stretch-slim
-
-on:
-  push:
-    paths:
-      - functions.sh
-      - test-build.sh
-      - test-image.bats
-      - 14/stretch-slim/Dockerfile
-  pull_request:
-    paths:
-      - functions.sh
-      - test-build.sh
-      - test-image.bats
-      - 14/stretch-slim/Dockerfile
-
-jobs:
-  build:
-    name: 14 on stretch-slim
-    runs-on: ubuntu-latest
-    steps:
-      - uses: actions/checkout@v2
-      - run: sudo apt-get install bats
-      - run: ./test-build.sh 14 stretch-slim
diff --git a/.github/workflows/14-stretch.yml b/.github/workflows/14-stretch.yml
deleted file mode 100644
index dfbfea496..000000000
--- a/.github/workflows/14-stretch.yml
+++ /dev/null
@@ -1,24 +0,0 @@
-name: 14 on stretch
-
-on:
-  push:
-    paths:
-      - functions.sh
-      - test-build.sh
-      - test-image.bats
-      - 14/stretch/Dockerfile
-  pull_request:
-    paths:
-      - functions.sh
-      - test-build.sh
-      - test-image.bats
-      - 14/stretch/Dockerfile
-
-jobs:
-  build:
-    name: 14 on stretch
-    runs-on: ubuntu-latest
-    steps:
-      - uses: actions/checkout@v2
-      - run: sudo apt-get install bats
-      - run: ./test-build.sh 14 stretch
diff --git a/.github/workflows/build-test.yml b/.github/workflows/build-test.yml
new file mode 100644
index 000000000..16483a9a3
--- /dev/null
+++ b/.github/workflows/build-test.yml
@@ -0,0 +1,89 @@
+name: build-test
+
+on:
+  push:
+    paths:
+      - "**/Dockerfile"
+      - "**/docker-entrypoint.sh"
+      - genMatrix.js
+      - ".github/workflows/build-test.yml"
+
+  pull_request:
+    paths:
+      - "**/Dockerfile"
+      - "**/docker-entrypoint.sh"
+      - genMatrix.js
+      - ".github/workflows/build-test.yml"
+
+jobs:
+  gen-matrix:
+    name: generate-matrix
+    runs-on: ubuntu-latest
+
+    steps:
+      - name: Calculate file differences
+        uses: lots0logs/gh-action-get-changed-files@2.1.4
+        id: diff
+        with:
+          token: ${{ secrets.GITHUB_TOKEN }}
+
+      - name: Checkout
+        uses: actions/checkout@v2
+
+      - name: Generate testing matrix
+        uses: actions/github-script@v3
+        id: generator
+        with:
+          github-token: ${{ secrets.GITHUB_TOKEN }}
+          script: |
+            const script = require(`${process.env.GITHUB_WORKSPACE}/genMatrix.js`)
+            return script(
+              ${{ steps.diff.outputs.added }},
+              ${{ steps.diff.outputs.modified }},
+              ${{ steps.diff.outputs.renamed }},
+            );
+
+    outputs:
+      matrix: ${{ steps.generator.outputs.result }}
+
+  build:
+    if: ${{ fromJson(needs.gen-matrix.outputs.matrix) }}
+    needs: gen-matrix
+    name: build
+    runs-on: ubuntu-latest
+    timeout-minutes: 60
+    strategy:
+      fail-fast: false
+      matrix: ${{ fromJson(needs.gen-matrix.outputs.matrix) }}
+
+    steps:
+      - name: Get short node version
+        uses: actions/github-script@v3
+        id: short-version
+        with:
+          result-encoding: string
+          script: return "${{ matrix.version }}".split('.')[0]
+
+      - name: Checkout
+        uses: actions/checkout@v2
+
+      - name: Build image
+        uses: docker/build-push-action@v2
+        with:
+          push: false
+          load: true
+          context: .
+          file: ./${{ steps.short-version.outputs.result }}/${{ matrix.variant }}/Dockerfile
+          tags: node:${{ matrix.version }}-${{ matrix.variant }}
+
+      - name: Test for node version
+        run: |
+          image_node_version=$(docker run --rm node:${{ matrix.version }}-${{ matrix.variant }} node --print "process.versions.node")
+          echo "Expected: \"${{ matrix.version }}\", Got: \"${image_node_version}\""
+          [ "${image_node_version}" == "${{ matrix.version }}" ]
+
+      - name: Test for npm
+        run: docker run --rm node:${{ matrix.version }}-${{ matrix.variant }} npm --version
+
+      - name: Test for yarn
+        run: docker run --rm node:${{ matrix.version }}-${{ matrix.variant }} yarn --version
diff --git a/.github/workflows/dockerfiles.yml b/.github/workflows/dockerfiles.yml
deleted file mode 100644
index a9da1ab7e..000000000
--- a/.github/workflows/dockerfiles.yml
+++ /dev/null
@@ -1,11 +0,0 @@
-name: Check for out of sync YAML pipeline files
-
-on: [pull_request]
-
-jobs:
-  regen:
-    runs-on: ubuntu-latest
-    steps:
-      - uses: actions/checkout@v2
-      - run: ./update.sh -t
-      - run: git diff --color --exit-code
diff --git a/genMatrix.js b/genMatrix.js
new file mode 100644
index 000000000..9f57ea509
--- /dev/null
+++ b/genMatrix.js
@@ -0,0 +1,80 @@
+'use strict';
+const path = require('path');
+const fs = require('fs');
+
+const testFiles = [
+  'genMatrix.js',
+  '.github/workflows/build-test.yml',
+];
+
+const nodeDirRegex = /^\d+$/;
+
+const areTestFilesChanged = (changedFiles) => changedFiles
+  .some((file) => testFiles.includes(file));
+
+// Returns a list of the child directories in the given path
+const getChildDirectories = (parent) => fs.readdirSync(parent, { withFileTypes: true })
+  .filter((dirent) => dirent.isDirectory())
+  .map(({ name }) => path.resolve(parent, name));
+
+const getNodeVerionDirs = (base) => getChildDirectories(base)
+  .filter((childPath) => nodeDirRegex.test(path.basename(childPath)));
+
+// Returns the paths of Dockerfiles that are at: base/*/Dockerfile
+const getDockerfilesInChildDirs = (base) => getChildDirectories(base)
+  .map((childDir) => path.resolve(childDir, 'Dockerfile'));
+
+const getAllDockerfiles = (base) => getNodeVerionDirs(base).flatMap(getDockerfilesInChildDirs);
+
+const getAffectedDockerfiles = (filesAdded, filesModified, filesRenamed) => {
+  const files = [
+    ...filesAdded,
+    ...filesModified,
+    ...filesRenamed,
+  ];
+
+  // If the test files were changed, include everything
+  if (areTestFilesChanged(files)) {
+    console.log('Test files changed so scheduling all Dockerfiles');
+    return getAllDockerfiles(__dirname);
+  }
+
+  const modifiedDockerfiles = files.filter((file) => file.endsWith('/Dockerfile'));
+
+  // Get Dockerfiles affected by modified docker-entrypoint.sh files
+  const entrypointAffectedDockerfiles = files
+    .filter((file) => file.endsWith('/docker-entrypoint.sh'))
+    .map((file) => path.resolve(path.dirname(file), 'Dockerfile'));
+
+  return [
+    ...modifiedDockerfiles,
+    ...entrypointAffectedDockerfiles,
+  ];
+};
+
+const getFullNodeVersionFromDockerfile = (file) => fs.readFileSync(file, 'utf8')
+  .match(/^ENV NODE_VERSION (\d*\.*\d*\.\d*)/m)[1];
+
+const getDockerfileMatrixEntry = (file) => {
+  const [variant] = path.dirname(file).split(path.sep).slice(-1);
+
+  const version = getFullNodeVersionFromDockerfile(file);
+
+  return {
+    version,
+    variant,
+  };
+};
+
+const generateBuildMatrix = (filesAdded, filesModified, filesRenamed) => {
+  const dockerfiles = [...new Set(getAffectedDockerfiles(filesAdded, filesModified, filesRenamed))];
+
+  const entries = dockerfiles.map(getDockerfileMatrixEntry);
+
+  // Return null if there are no entries so we can skip the matrix step
+  return entries.length
+    ? { include: entries }
+    : null;
+};
+
+module.exports = generateBuildMatrix;
diff --git a/test-build.sh b/test-build.sh
deleted file mode 100755
index 6614725d3..000000000
--- a/test-build.sh
+++ /dev/null
@@ -1,93 +0,0 @@
-#!/usr/bin/env bash
-#
-# Run a test build for all images.
-
-set -euo pipefail
-
-. functions.sh
-
-# Convert comma delimited cli arguments to arrays
-# E.g. ./test-build.sh 10,12 slim,alpine
-# "10,12" becomes "10 12" and "slim,alpine" becomes "slim alpine"
-IFS=',' read -ra versions_arg <<< "${1:-}"
-IFS=',' read -ra variant_arg <<< "${2:-}"
-
-default_variant=$(get_config "./" "default_variant")
-
-function build() {
-  local version
-  local tag
-  local variant
-  local full_tag
-  local path
-  version="$1"
-  shift
-  variant="$1"
-  shift
-  tag="$1"
-  shift
-
-  full_tag=$(get_full_tag "${variant}" "${tag}")
-  path=$(get_path "${version}" "${variant}")
-
-  info "Building ${full_tag}..."
-
-  if ! docker build --cpuset-cpus="0,1" -t node:"${full_tag}" "${path}"; then
-    fatal "Build of ${full_tag} failed!"
-  fi
-  info "Build of ${full_tag} succeeded."
-}
-
-function test_image() {
-  local full_version
-  local variant
-  local tag
-  local full_tag
-  full_version="$1"
-  shift
-  variant="$1"
-  shift
-  tag="$1"
-  shift
-
-  full_tag=$(get_full_tag "${variant}" "${tag}")
-
-  info "Testing ${full_tag}"
-  (
-    export full_version=${full_version}
-    export full_tag=${full_tag}
-    bats test-image.bats
-  )
-}
-
-cd "$(cd "${0%/*}" && pwd -P)" || exit
-
-IFS=' ' read -ra versions <<< "$(get_versions . "${versions_arg[@]}")"
-if [ ${#versions[@]} -eq 0 ]; then
-  fatal "No valid versions found!"
-fi
-
-for version in "${versions[@]}"; do
-  # Skip "docs" and other non-docker directories
-  [ -f "${version}/Dockerfile" ] || [ -a "${version}/${default_variant}/Dockerfile" ] || continue
-
-  tag=$(get_tag "${version}")
-  full_version=$(get_full_version "${version}")
-
-  # Get supported variants according to the target architecture.
-  # See details in function.sh
-  IFS=' ' read -ra variants <<< "$(get_variants "$(dirname "${version}")" "${variant_arg[@]}")"
-
-  for variant in "${variants[@]}"; do
-    # Skip non-docker directories
-    [ -f "${version}/${variant}/Dockerfile" ] || continue
-
-    build "${version}" "${variant}" "${tag}"
-    test_image "${full_version}" "${variant}" "${tag}"
-  done
-
-done
-
-info "All builds successful!"
-
-exit 0
diff --git a/test-image.bats b/test-image.bats
deleted file mode 100755
index b424b95a4..000000000
--- a/test-image.bats
+++ /dev/null
@@ -1,17 +0,0 @@
-#!/usr/bin/env bats
-
-@test "Test for node and version" {
-  run docker run --rm node:"$full_tag" node -e "process.stdout.write(process.versions.node)"
-  [ "$status" -eq 0 ]
-  [ "$output" == "${full_version}" ]
-}
-
-@test "Test for npm" {
-  run docker run --rm node:"$full_tag" npm --version
-  [ "$status" -eq 0 ]
-}
-
-@test "Test for yarn" {
-  run docker run --rm node:"$full_tag" yarn --version
-  [ "$status" -eq 0 ]
-}
diff --git a/update.sh b/update.sh
index eaa3e78e1..507af21a7 100755
--- a/update.sh
+++ b/update.sh
@@ -18,7 +18,6 @@ function usage() {
     - update.sh 8 buster-slim,buster # Update only buster's slim and buster variants for version 8
     - update.sh -s 8 stretch         # Update only stretch variant for version 8, skip updating Alpine and Yarn
     - update.sh . alpine             # Update the alpine variant for all versions
-    - update.sh -b                   # Update CI files only
 
   OPTIONS:
     -s Security update; skip updating the yarn and alpine versions.
@@ -29,17 +28,12 @@ EOF
 }
 
 SKIP=false
-CI_ONLY=false
-while getopts "sbh" opt; do
+while getopts "sh" opt; do
   case "${opt}" in
     s)
       SKIP=true
       shift
       ;;
-    b)
-      CI_ONLY=true
-      shift
-      ;;
     h)
       usage
       exit
@@ -197,56 +191,19 @@ function update_node_version() {
   )
 }
 
-function add_stage() {
-  local baseuri=${1}
-  shift
-  local version=${1}
-  shift
-  local variant=${1}
-  shift
-
-  echo "name: ${version} on ${variant}
-
-on:
-  push:
-    paths:
-      - functions.sh
-      - test-build.sh
-      - test-image.bats
-      - ${version}/${variant}/Dockerfile
-  pull_request:
-    paths:
-      - functions.sh
-      - test-build.sh
-      - test-image.bats
-      - ${version}/${variant}/Dockerfile
-
-jobs:
-  build:
-    name: ${version} on ${variant}
-    runs-on: ubuntu-latest
-    steps:
-      - uses: actions/checkout@v2
-      - run: sudo apt-get install bats
-      - run: ./test-build.sh ${version} ${variant}" > ".github/workflows/${version}-${variant}.yml"
-}
-
 for version in "${versions[@]}"; do
   parentpath=$(dirname "${version}")
   versionnum=$(basename "${version}")
   baseuri=$(get_config "${parentpath}" "baseuri")
   update_version=$(in_versions_to_update "${version}")
 
-  [ "${update_version}" -eq 0 ] && [ true != "$CI_ONLY" ] && info "Updating version ${version}..."
+  [ "${update_version}" -eq 0 ] && info "Updating version ${version}..."
 
   # Get supported variants according the target architecture
   # See details in function.sh
   IFS=' ' read -ra variants <<< "$(get_variants "${parentpath}")"
 
   if [ -f "${version}/Dockerfile" ]; then
-    add_stage "${baseuri}" "${version}" "default"
-    [ true = "$CI_ONLY" ] && continue
-
     if [ "${update_version}" -eq 0 ]; then
       update_node_version "${baseuri}" "${versionnum}" "${parentpath}/Dockerfile.template" "${version}/Dockerfile" &
     fi
@@ -255,8 +212,6 @@ for version in "${versions[@]}"; do
   for variant in "${variants[@]}"; do
     # Skip non-docker directories
     [ -f "${version}/${variant}/Dockerfile" ] || continue
-    add_stage "${baseuri}" "${version}" "${variant}"
-    [ true = "$CI_ONLY" ] && continue
 
     update_variant=$(in_variants_to_update "${variant}")
     template_file="${parentpath}/Dockerfile-${variant}.template"