Add Scalpel for incremental CI builds

.github/generate-test-matrix.sh

@@ -0,0 +1,96 @@
+#!/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.
+#
+
+# Reads a Scalpel report and emits GitHub Actions matrix + modules outputs.
+# Usage: generate-test-matrix.sh <scalpel-report.json>
+# Output lines are in key=value format suitable for >> $GITHUB_OUTPUT.
+
+set -euo pipefail
+
+REPORT="${1:?Usage: $0 <scalpel-report.json>}"
+MAX_GROUPS=10
+
+# Unique top-level modules (first path component of each affected module path)
+ALL=()
+if [ -f "$REPORT" ]; then
+    while IFS= read -r line; do
+        ALL+=("$line")
+    done < <(jq -r '[.affectedModules[] | select(.path != "") | .path | split("/")[0]] | unique[]' "$REPORT")
+fi
+
+# Fall back to all reactor modules when Scalpel found nothing or wrote no report
+# (no base branch configured, e.g. a plain push with no PR context)
+if [ ${#ALL[@]} -eq 0 ]; then
+    while IFS= read -r line; do
+        ALL+=("$line")
+    done < <(grep '<module>' pom.xml | sed 's|.*<module>\(.*\)</module>.*|\1|' | sort)
+fi
+
+# Separate single-module and multi-module projects.
+# Multi-module projects get a dedicated native test group (they run from their own
+# root directory) and are expanded with sub-modules for the -pl modules list.
+SINGLE=()
+MULTI=()
+for m in "${ALL[@]}"; do
+    if grep -q '<module>' "$m/pom.xml" 2>/dev/null; then
+        MULTI+=("$m")
+    else
+        SINGLE+=("$m")
+    fi
+done
+
+# Round-robin distribution of single-module projects into at most MAX_GROUPS groups
+GROUP_TESTS=()
+for i in "${!SINGLE[@]}"; do
+    gid=$((i % MAX_GROUPS))
+    if [[ -z "${GROUP_TESTS[$gid]+x}" ]]; then
+        GROUP_TESTS[$gid]="${SINGLE[$i]}"
+    else
+        GROUP_TESTS[$gid]="${GROUP_TESTS[$gid]},${SINGLE[$i]}"
+    fi
+done
+
+# Build matrix JSON include array
+INCLUDE="["
+SEP=""
+for gid in $(echo "${!GROUP_TESTS[@]}" | tr ' ' '\n' | sort -n); do
+    INCLUDE+="${SEP}$(printf '{"name":"group-%02d","tests":"%s"}' $((gid + 1)) "${GROUP_TESTS[$gid]}")"
+    SEP=","
+done
+# Multi-module projects each get their own dedicated group at the end
+NUM_GROUPS=${#GROUP_TESTS[@]}
+for i in "${!MULTI[@]}"; do
+    INCLUDE+="${SEP}$(printf '{"name":"group-%02d","tests":"%s"}' $((NUM_GROUPS + i + 1)) "${MULTI[$i]}")"
+    SEP=","
+done
+INCLUDE+="]"
+
+# Build expanded module list for -pl: multi-module projects include their sub-modules
+# so that Maven builds the full project tree rather than just the parent POM.
+EXPANDED=()
+for m in "${ALL[@]}"; do
+    EXPANDED+=("$m")
+    if grep -q '<module>' "$m/pom.xml" 2>/dev/null; then
+        while IFS= read -r submod; do
+            [ -n "$submod" ] && EXPANDED+=("$m/$submod")
+        done < <(grep '<module>' "$m/pom.xml" | sed 's|.*<module>\(.*\)</module>.*|\1|')
+    fi
+done
+
+echo "matrix={\"include\":${INCLUDE}}"
+echo "modules=$(IFS=,; echo "${EXPANDED[*]}")"

.github/workflows/ci-build.yaml

@@ -57,6 +57,7 @@ jobs:
     runs-on: ubuntu-latest
     outputs:
       matrix: ${{ steps.set-itest-matrix.outputs.matrix }}
+      modules: ${{ steps.set-itest-matrix.outputs.modules }}
     steps:
       - name: Set up JDK 17
         uses: actions/setup-java@v5
@@ -103,13 +104,22 @@ jobs:
             license:check \
             net.revelc.code.formatter:formatter-maven-plugin:validate \
             net.revelc.code:impsort-maven-plugin:check
+      - name: Fetch base branch for Scalpel
+        if: github.event_name == 'pull_request' && !contains(github.event.pull_request.labels.*.name, 'ci/disable-incremental')
+        run: git fetch --unshallow origin ${{ github.base_ref }}
       - name: Build Camel Quarkus Examples
         run: |
-          ./mvnw ${MAVEN_ARGS} clean install -DskipTests -Dquarkus.build.skip
+          ./mvnw ${MAVEN_ARGS} clean install -DskipTests -Dquarkus.build.skip \
+            -Dscalpel.enabled=true \
+            -Dscalpel.mode=report \
+            -Dscalpel.reportFile=${{ runner.temp }}/scalpel-report.json
       - name: Fail if there are uncommitted changes
         shell: bash
         run: |
           [[ -z $(git status --porcelain) ]] || { echo 'There are uncommitted changes'; git status; exit 1; }
+      - name: Setup Integration Test Matrix
+        id: set-itest-matrix
+        run: bash .github/generate-test-matrix.sh '${{ runner.temp }}/scalpel-report.json' >> $GITHUB_OUTPUT
       - name: Tar Maven Repo
         shell: bash
         run: |
@@ -120,12 +130,6 @@ jobs:
           name: maven-repo
           path: ${{ runner.temp }}/maven-repo.tar.zst
           retention-days: 1
-      - name: Setup Integration Test Matrix
-        id: set-itest-matrix
-        run: |
-          sudo apt install groovy -y --no-install-recommends
-          TEST_GROUPS=$(groovy .github/generate-test-groups.groovy)
-          echo "matrix=${TEST_GROUPS}" >> $GITHUB_OUTPUT
 
   integration-tests:
     name: Integration Tests - ${{matrix.name}}
@@ -214,7 +218,8 @@ jobs:
       - name: Integration Tests
         shell: bash
         run: |
-          ./mvnw ${MAVEN_ARGS} clean test
+          ./mvnw ${MAVEN_ARGS} clean test \
+            -pl ${{ needs.initial-mvn-install.outputs.modules }}
       - name: Fail if there are uncommitted changes
         shell: bash
         run: |
@@ -248,7 +253,8 @@ jobs:
       - name: Integration Tests
         shell: bash
         run: |
-          ./mvnw ${MAVEN_ARGS} -Dskip-testcontainers-tests clean test
+          ./mvnw ${MAVEN_ARGS} -Dskip-testcontainers-tests clean test \
+            -pl ${{ needs.initial-mvn-install.outputs.modules }}
       - name: Fail if there are uncommitted changes
         shell: bash
         run: |

.mvn/extensions.xml

@@ -0,0 +1,8 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<extensions>
+    <extension>
+        <groupId>eu.maveniverse.maven.scalpel</groupId>
+        <artifactId>extension</artifactId>
+        <version>0.3.4</version>
+    </extension>
+</extensions>

.mvn/maven.config

@@ -0,0 +1 @@
+-Dscalpel.enabled=false