feat(shellcheck): add shell check for shell and pipeline

.github/workflows/main.yml

@@ -26,11 +26,5 @@ jobs:
       - uses: actions/checkout@v2
 
       # Runs a single command using the runners shell
-      - name: Run a one-line script
+      - name: shell check
-        run: echo Hello, world!
+        run: docker-compose run --rm shellcheck ./validate.sh
-
-      # Runs a set of commands using the runners shell
-      - name: Run a multi-line script
-        run: |
-          echo Add other actions to build,
-          echo test, and deploy your project.

docker-compose.yaml

@@ -0,0 +1,8 @@
+---
+version: '3.9'
+services:
+  shellcheck:
+    image: koalaman/shellcheck-alpine:latest
+    volumes:
+      - ".:/build"
+    working_dir: /build

validate.sh

@@ -0,0 +1,11 @@
+#!/bin/sh -l
+
+set -euo pipefile
+
+rc=0
+for filename in $(find ./* -name '*.sh'); do
+  echo "Validating"
+  shellcheck "${filename}" || exit $?
+done
+
+exit $?