Add shell script linting with shellcheck for better portability

.semaphoreci/job2.sh

@@ -5,4 +5,4 @@ ci_retry make validate
 
 if [ -n "$SHOULD_TEST" ]; then ci_retry make test-unit; fi
 
-if [ -n "$SHOULD_TEST" ]; then make -j${N_MAKE_JOBS} crossbinary-default-parallel; fi
+if [ -n "$SHOULD_TEST" ]; then make -j"${N_MAKE_JOBS}" crossbinary-default-parallel; fi

.semaphoreci/setup.sh

@@ -3,9 +3,10 @@ set -e
 
 export DOCKER_VERSION=17.03.1
 
+# shellcheck source=/dev/null
 source .semaphoreci/vars
 
-if [ -z "${PULL_REQUEST_NUMBER}" ]; then SHOULD_TEST="-*-"; else TEMP_STORAGE=$(curl --silent https://patch-diff.githubusercontent.com/raw/containous/traefik/pull/${PULL_REQUEST_NUMBER}.diff | patch --dry-run -p1 -R); fi
+if [ -z "${PULL_REQUEST_NUMBER}" ]; then SHOULD_TEST="-*-"; else TEMP_STORAGE=$(curl --silent https://patch-diff.githubusercontent.com/raw/containous/traefik/pull/"${PULL_REQUEST_NUMBER}".diff | patch --dry-run -p1 -R); fi
 
 if [ -n "$TEMP_STORAGE" ]; then SHOULD_TEST=$(echo "$TEMP_STORAGE" | grep -Ev '(.md|.yaml|.yml)' || :); fi
 

.semaphoreci/vars

@@ -24,8 +24,8 @@ function ci_retry {
     until [ $n -ge $NRETRY ]
     do
         "$@" && break
-        n=$[$n+1]
-        echo "$@ failed, attempt ${n}/${NRETRY}"
+        n=$((n+1))
+        echo "${*} failed, attempt ${n}/${NRETRY}"
         sleep $NSLEEP
     done
 
@@ -34,4 +34,3 @@ function ci_retry {
 }
 
 export -f ci_retry
-

Makefile

@@ -96,10 +96,12 @@ test-integration: $(PRE_TARGET)
 ## Validate code and docs
 validate-files: $(PRE_TARGET)
 	$(if $(PRE_TARGET),$(DOCKER_RUN_TRAEFIK)) ./script/make.sh generate validate-lint validate-misspell
+	bash $(CURDIR)/script/validate-shell-script.sh
 
 ## Validate code, docs, and vendor
 validate: $(PRE_TARGET)
 	$(if $(PRE_TARGET),$(DOCKER_RUN_TRAEFIK)) ./script/make.sh generate validate-lint validate-misspell validate-vendor
+	bash $(CURDIR)/script/validate-shell-script.sh
 
 ## Clean up static directory and build a Docker Traefik image
 build-image: binary

docs/content/contributing/building-testing.md

@@ -43,7 +43,7 @@ $ ls dist/
 traefik*
 ```
 
-The following targets can be executed outside Docker (we don't recommend that):
+The following targets can be executed outside Docker by setting the variable `PRE_TARGET` to an empty string (we don't recommend that):
 
 - `test-unit`
 - `test-integration`
@@ -61,24 +61,24 @@ PRE_TARGET= make test-unit
 You need `go` v1.12+.
 
 !!! tip "Source Directory"
- 
+
     It is recommended that you clone Traefik into the `~/go/src/github.com/containous/traefik` directory.
     This is the official golang workspace hierarchy that will allow dependencies to be properly resolved.
 
 !!! note "Environment"
 
     Set your `GOPATH` and `PATH` variable to be set to `~/go` via:
-    
+
     ```bash
     export GOPATH=~/go
     export PATH=$PATH:$GOPATH/bin
     ```
- 
+
     For convenience, add `GOPATH` and `PATH` to your `.bashrc` or `.bash_profile`
-    
+
     Verify your environment is setup properly by running `$ go env`.
     Depending on your OS and environment, you should see an output similar to:
-    
+
     ```bash
     GOARCH="amd64"
     GOBIN=""

script/binary

@@ -8,9 +8,9 @@ fi
 
 rm -f dist/traefik
 
-FLAGS=""
+FLAGS=()
 if [ -n "$VERBOSE" ]; then
-    FLAGS="${FLAGS} -v"
+    FLAGS+=(-v)
 fi
 
 if [ -z "$VERSION" ]; then
@@ -26,7 +26,7 @@ if [ -z "$DATE" ]; then
 fi
 
 # Build binaries
-CGO_ENABLED=0 GOGC=off go build $FLAGS -ldflags "-s -w \
+CGO_ENABLED=0 GOGC=off go build "${FLAGS[@]}" -ldflags "-s -w \
     -X github.com/containous/traefik/pkg/version.Version=$VERSION \
     -X github.com/containous/traefik/pkg/version.Codename=$CODENAME \
     -X github.com/containous/traefik/pkg/version.BuildDate=$DATE" \

script/crossbinary-default

@@ -27,12 +27,12 @@ GO_BUILD_OPT="-s -w -X ${GIT_REPO_URL}.Version=${VERSION} -X ${GIT_REPO_URL}.Cod
 # Build amd64 binaries
 OS_PLATFORM_ARG=(linux windows darwin)
 OS_ARCH_ARG=(amd64)
-for OS in ${OS_PLATFORM_ARG[@]}; do
+for OS in "${OS_PLATFORM_ARG[@]}"; do
   BIN_EXT=''
   if [ "$OS" == "windows" ]; then
     BIN_EXT='.exe'
   fi
-  for ARCH in ${OS_ARCH_ARG[@]}; do
+  for ARCH in "${OS_ARCH_ARG[@]}"; do
     echo "Building binary for ${OS}/${ARCH}..."
     GOARCH=${ARCH} GOOS=${OS} CGO_ENABLED=0 ${GO_BUILD_CMD} "${GO_BUILD_OPT}" -o "dist/traefik_${OS}-${ARCH}${BIN_EXT}" ./cmd/traefik/
   done
@@ -41,8 +41,8 @@ done
 # Build arm64 binaries
 OS_PLATFORM_ARG=(linux)
 OS_ARCH_ARG=(arm64)
-for OS in ${OS_PLATFORM_ARG[@]}; do
-  for ARCH in ${OS_ARCH_ARG[@]}; do
+for OS in "${OS_PLATFORM_ARG[@]}"; do
+  for ARCH in "${OS_ARCH_ARG[@]}"; do
     echo "Building binary for ${OS}/${ARCH}..."
     GOARCH=${ARCH} GOOS=${OS} CGO_ENABLED=0 ${GO_BUILD_CMD} "${GO_BUILD_OPT}" -o "dist/traefik_${OS}-${ARCH}" ./cmd/traefik/
   done

script/deploy.sh

@@ -8,12 +8,16 @@ else
   exit 0
 fi
 
+SCRIPT_DIR="$( cd "$( dirname "${0}" )" && pwd -P)"
+
 git config --global user.email "$TRAEFIKER_EMAIL"
 git config --global user.name "Traefiker"
 
 # load ssh key
 echo "Loading key..."
-openssl aes-256-cbc -K $encrypted_f9e835a425bc_key -iv $encrypted_f9e835a425bc_iv -in .travis/traefiker_rsa.enc -out ~/.ssh/traefiker_rsa -d
+${encrypted_f9e835a425bc_key:?}
+${encrypted_f9e835a425bc_iv:?}
+openssl aes-256-cbc -K "${encrypted_f9e835a425bc_key}" -iv "${encrypted_f9e835a425bc_iv}" -in .travis/traefiker_rsa.enc -out ~/.ssh/traefiker_rsa -d
 eval "$(ssh-agent -s)"
 chmod 600 ~/.ssh/traefiker_rsa
 ssh-add ~/.ssh/traefiker_rsa
@@ -21,14 +25,14 @@ ssh-add ~/.ssh/traefiker_rsa
 # update traefik-library-image repo (official Docker image)
 echo "Updating traefik-library-imag repo..."
 git clone git@github.com:containous/traefik-library-image.git
-cd traefik-library-image
-./updatev2.sh $VERSION
+cd "${SCRIPT_DIR}"/traefik-library-image
+"${SCRIPT_DIR}"/traefik-library-image/updatev2.sh "${VERSION}"
 git add -A
-echo $VERSION | git commit --file -
-echo $VERSION | git tag -a $VERSION --file -
+echo "${VERSION}" | git commit --file -
+echo "${VERSION}" | git tag -a "${VERSION}" --file -
 git push -q --follow-tags -u origin master > /dev/null 2>&1
 
-cd ..
+cd "${SCRIPT_DIR}"
 rm -Rf traefik-library-image/
 
-echo "Deployed"
+echo "Deployed"

script/make.sh

@@ -11,20 +11,21 @@ DEFAULT_BUNDLES=(
 	test-integration
 )
 
+SCRIPT_DIR="$(cd "$(dirname "${0}")" && pwd -P)"
+
 bundle() {
     local bundle="$1"; shift
-    echo "---> Making bundle: $(basename "$bundle") (in $DEST)"
-    source "script/$bundle" "$@"
+    echo "---> Making bundle: $(basename "$bundle") (in $SCRIPT_DIR)"
+    # shellcheck source=/dev/null
+    source "${SCRIPT_DIR}/$bundle"
 }
 
 if [ $# -lt 1 ]; then
-    bundles=(${DEFAULT_BUNDLES[@]})
+    bundles=${DEFAULT_BUNDLES[*]}
 else
-    bundles=($@)
+    bundles=${*}
 fi
-for bundle in ${bundles[@]}; do
-    export DEST=.
-    ABS_DEST="$(cd "$DEST" && pwd -P)"
+for bundle in ${bundles[*]}; do
     bundle "$bundle"
     echo
 done

script/test-integration

@@ -1,28 +1,26 @@
 #!/usr/bin/env bash
 set -e
 
-SCRIPT_DIR="$( cd "$( dirname "${0}" )" && pwd -P)"; export SCRIPT_DIR
 export DEST=.
 
-TESTFLAGS="${TESTFLAGS} -test.timeout=20m -check.v"
+TESTFLAGS+=("-test.timeout=20m" -check.v)
 
 if [ -n "$VERBOSE" ]; then
-    TESTFLAGS="${TESTFLAGS} -v"
+    TESTFLAGS+=(-v)
 elif [ -n "$VERBOSE_INTEGRATION" ]; then
-    TESTFLAGS="${TESTFLAGS} -v"
+    TESTFLAGS+=(-v)
 fi
 
-
 cd integration
-echo "Testing against…"
+echo "Testing against..."
 docker version
 
 if [ -n "$TEST_CONTAINER" ]; then
-echo "Testing from container…"
-CGO_ENABLED=0 go test -integration -container $TESTFLAGS
+    echo "Testing from container…"
+    CGO_ENABLED=0 go test -integration -container "${TESTFLAGS[@]}"
 fi
 
 if [ -n "$TEST_HOST" ]; then
-echo "Testing from host…"
-CGO_ENABLED=0 go test -integration -host $TESTFLAGS
+    echo "Testing from host…"
+    CGO_ENABLED=0 go test -integration -host "${TESTFLAGS[@]}"
 fi

script/test-unit

@@ -11,17 +11,17 @@ GREEN=$'\033[32m'
 TEXTRESET=$'\033[0m' # reset the foreground colour
 
 # -failfast -timeout=5m
-TESTFLAGS="-cover -coverprofile=cover.out ${TESTFLAGS}"
+TESTFLAGS=(-cover "-coverprofile=cover.out" "${TESTFLAGS}")
 
 if [ -n "$VERBOSE" ]; then
-    TESTFLAGS="${TESTFLAGS} -v"
+    TESTFLAGS+=(-v)
 elif [ -n "$VERBOSE_UNIT" ]; then
-    TESTFLAGS="${TESTFLAGS} -v"
+    TESTFLAGS+=(-v)
 fi
 
 set +e
 
-go test ${TESTFLAGS} ./pkg/...
+go test "${TESTFLAGS[@]}" ./pkg/...
 
 CODE=$?
 if [ ${CODE} != 0 ]; then

script/update-cert.sh

@@ -13,11 +13,11 @@ docker pull $CERT_IMAGE
 
 # Fetch the latest certificates.
 ID=$(docker run -d $CERT_IMAGE sh -c "apk --update upgrade && apk add ca-certificates && update-ca-certificates")
-docker logs -f $ID
-docker wait $ID
+docker logs -f "${ID}"
+docker wait "${ID}"
 
 # Update the local certificates.
-docker cp $ID:/etc/ssl/certs/ca-certificates.crt .
+docker cp "${ID}":/etc/ssl/certs/ca-certificates.crt "${SCRIPT_DIR}"
 
 # Cleanup.
-docker rm -f $ID
+docker rm -f "${ID}"

script/update-generated-crd-code.sh

@@ -3,12 +3,12 @@
 HACK_DIR="$( cd "$( dirname "${0}" )" && pwd -P)"; export HACK_DIR
 REPO_ROOT=${HACK_DIR}/..
 
-${REPO_ROOT}/vendor/k8s.io/code-generator/generate-groups.sh \
+"${REPO_ROOT}"/vendor/k8s.io/code-generator/generate-groups.sh \
   all \
   github.com/containous/traefik/pkg/provider/kubernetes/crd/generated \
   github.com/containous/traefik/pkg/provider/kubernetes/crd \
   traefik:v1alpha1 \
-  --go-header-file ${HACK_DIR}/boilerplate.go.tmpl \
-  $@
+  --go-header-file "${HACK_DIR}"/boilerplate.go.tmpl \
+  "$@"
 
-deepcopy-gen  --input-dirs github.com/containous/traefik/pkg/config  -O zz_generated.deepcopy --go-header-file ${HACK_DIR}/boilerplate.go.tmpl
+deepcopy-gen  --input-dirs github.com/containous/traefik/pkg/config  -O zz_generated.deepcopy --go-header-file "${HACK_DIR}"/boilerplate.go.tmpl

script/validate-misspell

@@ -1,8 +1,9 @@
 #!/usr/bin/env bash
 
-IFS=$'\n'
-files=( $( git ls-files 'docs/*.md' *.md ) )
-unset IFS
+SCRIPT_DIR="$( cd "$( dirname "${0}" )" && pwd -P)"
+files=()
+while IFS='' read -r line; do files+=("$line"); done < <(git ls-files "${SCRIPT_DIR}"/../'docs/*.md' "${SCRIPT_DIR}"/../*.md)
+
 
 errors=()
 for f in "${files[@]}"; do

script/validate-shell-script.sh

@@ -0,0 +1,24 @@
+#!/usr/bin/env bash
+
+set -eu -o pipefail
+
+script_dir="$( cd "$( dirname "${0}" )" && pwd -P)"
+
+if command -v shellcheck
+then
+    # The list of shell script come from the (grep ...) command, feeding the loop
+    while IFS= read -r script_to_check
+    do
+        # The shellcheck command are run in background, to have an overview of the linter (instead of a fail at first issue)
+        shellcheck "${script_to_check}" &
+    done < <( # Search all the repository for sh and bash shebangs, excluding .js and .md files
+        # the folders ".git" and "vendor" are also ignored
+        grep -rI '#!/' "${script_dir}"/.. \
+        | grep 'sh' | grep -v '.js' | grep -v '.md' \
+        | grep -v '.git/' | grep -v 'vendor/' \
+        | cut -d':' -f1
+    )
+    wait # Wait for all background command to be completed
+else
+    echo "== Command shellcheck not found in your PATH. No shell script checked."
+fi