[CI] Skip CI when only docs are updated (#3722)

Jenkinsfile

@@ -53,16 +53,12 @@ pipeline {
                             }
                         }
 
-                        stage('Check environment') {
-                            steps {
-                                sh 'env'
-                                sh 'pwd'
-                                sh 'ls'
-                                sh 'git status'
-                            }
-                        }
-
                         stage('Test & Report') {
+                            when {
+                                expression {
+                                    return sh(returnStatus: true, script: 'bash tools/ci/ci-build-condition.sh')
+                                }
+                            }
                             steps {
                                 sh './mvnw -P"agent,backend,ui,dist,CI-with-IT" -DrepoToken=${COVERALLS_REPO_TOKEN} -DpullRequest=${ghprbPullLink} clean cobertura:cobertura verify coveralls:report install'
                                 sh './mvnw javadoc:javadoc -Dmaven.test.skip=true'
@@ -70,6 +66,11 @@ pipeline {
                         }
 
                         stage('Check Dependencies Licenses') {
+                            when {
+                                expression {
+                                    return sh(returnStatus: true, script: 'bash tools/ci/ci-build-condition.sh')
+                                }
+                            }
                             steps {
                                 sh 'tar -zxf dist/apache-skywalking-apm-bin.tar.gz -C dist'
                                 sh 'tools/dependencies/check-LICENSE.sh'

tools/ci/agent-build-condition.sh

@@ -16,7 +16,7 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-bash -x $(dirname "$0")/changed.sh --any-of '^pom.xml$' \
+bash -x $(dirname "$0")/changed.sh --includes '^pom.xml$' \
   '^Jenkinsfile-Agent-.*$' \
   '^apm-application-toolkit/.*$' \
   '^apm-commons/.*$' \

tools/ci/changed.sh

@@ -16,43 +16,59 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-patterns=()
-any_of=0
+# Detect files' changed set
+# --includes: includes these files when detecting changed file sets, defaults to ^.*$, meaning all files will be checked
+# --excludes: excludes these files when detecting changed file sets
+# exit with status code 0 if no changed file matches the patterns, otherwise exit with status code non 0
+
+includes=('^.*$')
+excludes=()
+
+including=0
+excluding=1
 
 while [[ $# -gt 0 ]]; do
   case "$1" in
-    --any-of)
-      any_of=1
+    --includes)
+      including=1
+      excluding=0
+      includes=()
+      ;;
+    --excludes)
+      including=0
+      excluding=1
       ;;
     *)
-      patterns+=($1)
+      if [[ ${including} -eq 1 ]]; then
+        includes+=($1)
+      elif [[ ${excluding} -eq 1 ]]; then
+        excludes+=($1)
+      fi
       ;;
   esac
   shift
 done
 
-[[ ${#patterns[@]} -eq 0 ]] && echo 'No file pattern is specified, exiting' && exit 1
-
 changed_files=$(git diff --name-only origin/${ghprbTargetBranch:-master}..${ghprbActualCommit:-HEAD})
 
-test_results=()
-
 for file in ${changed_files}; do
-  for pattern in ${patterns[@]}; do
-    if [[ ${file} =~ ${pattern} ]]; then
-      test_results+=("Hit: ${file} matches pattern ${pattern}")
-    else
-      test_results+=("Miss: ${file} does not match pattern ${pattern}")
+  excluded=0
+  for exclude in ${excludes[@]}; do
+    if [[ ${file} =~ ${exclude} ]]; then
+      excluded=1
+      break
+    fi
+  done
+  if [[ ${excluded} -eq 1 ]]; then
+    echo "${file} is excluded"
+    continue
+  fi
+  for include in ${includes[@]}; do
+    if [[ ${file} =~ ${include} ]]; then
+      echo "${file} is changed"
+      exit 1
     fi
   done
 done
 
-IFS=$'\n' ; echo "${test_results[*]}"
-
-if [[ ${any_of} -eq 1 ]]; then
-  for test_result in ${test_results[@]}; do
-    [[ ${test_result} =~ ^Hit:.+$ ]] && echo ${test_result} && exit 1
-  done
-fi
-
-exit 0
+exit 0

tools/ci/ci-build-condition.sh

@@ -0,0 +1,19 @@
+#!/usr/bin/env bash
+#
+# 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.
+
+bash -x $(dirname "$0")/changed.sh --excludes '.*.md$'

tools/ci/e2e-build-condition.sh

@@ -16,7 +16,7 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-bash -x $(dirname "$0")/changed.sh --any-of '^pom.xml$' \
+bash -x $(dirname "$0")/changed.sh --includes '^pom.xml$' \
   '^Jenkinsfile-E2E$' \
   '^apm-commons/.*$' \
   '^apm-protocol/.*$' \