Lint with shellcheck (#500)

* Fix issues suggested by shellcheck
* Add shellcheck step in the test workflow

.github/workflows/test.yaml

@@ -73,6 +73,9 @@ jobs:
           skip-pkg-cache: true
           install-mode: "goinstall"
 
+      - name: Lint BASH script with shellcheck 🚨
+        uses: ludeeus/action-shellcheck@master
+
       - name: Run Go tests 🔬
         run: go test -p 1 -cover -covermode atomic -coverprofile=profile.cov -v ./...
         env:

setup.sh

@@ -4,25 +4,25 @@
 # the latest version of GatewayD from GitHub and install the plugins.
 
 # Get the latest released version of GatewayD from GitHub
-[ -z ${GATEWAYD_VERSION} ] && export GATEWAYD_VERSION=$(git ls-remote --tags --sort=v:refname "https://github.com/gatewayd-io/gatewayd" | cut -d/ -f3- | tail -n1)
+[ -z "${GATEWAYD_VERSION}" ] && GATEWAYD_VERSION=$(git ls-remote --tags --sort=v:refname "https://github.com/gatewayd-io/gatewayd" | cut -d/ -f3- | tail -n1) && export GATEWAYD_VERSION
 
 # Set the environment variables if they are not set
-[ -z ${GATEWAYD_FILES} ] && export GATEWAYD_FILES=/gatewayd-files
+[ -z "${GATEWAYD_FILES}" ] && GATEWAYD_FILES=/gatewayd-files && export GATEWAYD_FILES
 
 # Install the required packages
 apk add --no-cache curl git
 
 # Create the directory to store the gatewayd files
-[ -d ${GATEWAYD_FILES} ] || mkdir ${GATEWAYD_FILES}
+[ -d "${GATEWAYD_FILES}" ] || mkdir "${GATEWAYD_FILES}"
 
-cd ${GATEWAYD_FILES}
+cd "${GATEWAYD_FILES}" || exit 1
 
 # Download the GatewayD archive if it doesn't exist
-[ -f ${GATEWAYD_FILES}/gatewayd-linux-amd64-${GATEWAYD_VERSION}.tar.gz ] || curl -L https://github.com/gatewayd-io/gatewayd/releases/download/${GATEWAYD_VERSION}/gatewayd-linux-amd64-${GATEWAYD_VERSION}.tar.gz | tar zxvf -
+[ -f "${GATEWAYD_FILES}"/gatewayd-linux-amd64-"${GATEWAYD_VERSION}".tar.gz ] || curl -L https://github.com/gatewayd-io/gatewayd/releases/download/"${GATEWAYD_VERSION}"/gatewayd-linux-amd64-"${GATEWAYD_VERSION}".tar.gz | tar zxvf -
 chmod +x gatewayd
 
 # Install the GatewayD plugins
-${GATEWAYD_FILES}/gatewayd plugin install --skip-path-slip-verification --output-dir ${GATEWAYD_FILES} --plugin-config ${GATEWAYD_FILES}/gatewayd_plugins.yaml --cleanup=false --update --overwrite-config
+"${GATEWAYD_FILES}"/gatewayd plugin install --skip-path-slip-verification --output-dir "${GATEWAYD_FILES}" --plugin-config "${GATEWAYD_FILES}"/gatewayd_plugins.yaml --cleanup=false --update --overwrite-config
 
 # Replace the default Redis URL
-sed -i 's/redis:\/\/localhost:6379/redis:\/\/redis:6379/' ${GATEWAYD_FILES}/gatewayd_plugins.yaml
+sed -i 's/redis:\/\/localhost:6379/redis:\/\/redis:6379/' "${GATEWAYD_FILES}"/gatewayd_plugins.yaml