ci: add shellcheck linter (#6428)

.github/workflows/code-lint.yml

@@ -28,3 +28,18 @@ jobs:
         . ./ci/common.sh
         export_or_prefix
         make lint
+
+  sc-lint:
+    runs-on: ubuntu-latest
+    timeout-minutes: 5
+    steps:
+      - name: Checkout code
+        uses: actions/checkout@v2.4.0
+
+      - name: Shellcheck code
+        run: |
+          scversion="latest"
+          wget -O- "https://github.com/koalaman/shellcheck/releases/download/${scversion?}/shellcheck-${scversion?}.linux.x86_64.tar.xz" | tar -xJv
+          cp -av "shellcheck-${scversion}/shellcheck" /usr/local/bin/
+          shellcheck --version
+          git ls-files | grep ".sh$" | xargs -t shellcheck

.shellcheckrc

@@ -0,0 +1,25 @@
+#
+# Licensed to the Apache Software Foundation (ASF) under one or more
+# contributor license agreements.  See the NOTICE file distributed with
+# this work for additional information regarding copyright ownership.
+# The ASF licenses this file to You under the Apache License, Version 2.0
+# (the "License"); you may not use this file except in compliance with
+# the License.  You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+#
+
+# wiki link pattern https://github.com/koalaman/shellcheck/wiki/{code}
+# like SC2148, links to https://github.com/koalaman/shellcheck/wiki/SC2148
+
+disable=SC1083,SC1091
+disable=SC2002,SC2004,SC2006,SC2009,SC2010,SC2016,SC2024,SC2027,SC2034,SC2046,SC2048,SC2059
+disable=SC2068,SC2076,SC2086,SC2089,SC2090
+disable=SC2103,SC2126,SC2143,SC2148,SC2155,SC2157,SC2164,SC2181
+disable=SC2215,SC2216,SC2251,SC2260,SC3037

ci/linux_apisix_current_luarocks_runner.sh

@@ -48,7 +48,7 @@ script() {
     sudo PATH=$PATH apisix start
     sudo PATH=$PATH apisix stop
 
-    cat /usr/local/apisix/logs/error.log | grep '\[error\]' > /tmp/error.log | true
+    grep '\[error\]' /usr/local/apisix/logs/error.log > /tmp/error.log | true
     if [ -s /tmp/error.log ]; then
         echo "=====found error log====="
         cat /usr/local/apisix/logs/error.log

ci/linux_apisix_master_luarocks_runner.sh

@@ -53,7 +53,7 @@ script() {
     # apisix cli test
     # todo: need a more stable way
 
-    cat /usr/local/apisix/logs/error.log | grep '\[error\]' > /tmp/error.log | true
+    grep '\[error\]' /usr/local/apisix/logs/error.log > /tmp/error.log | true
     if [ -s /tmp/error.log ]; then
         echo "=====found error log====="
         cat /usr/local/apisix/logs/error.log