refactor: move java-common-protos, java-iam, java-showcase to top level (#12839)

Currently, the hermetic code generator can only move files to top level
folders. Rather than changing the generator, we will move the generated
code to the top level to also make it compatible with librarian.

Other fixes:
* The hermetic_build scripts had special case logic to force
regeneration of the entire repository if the common protos were found in
the generation_config.yaml. This is no longer necessary in
google-cloud-java as the nightly build regenerates everything
* Includes the OTel wait for metrics fix similar to #12880
* Removes configuration for GCS Maven Mirror as that mirror is no longer
updated and is missing dependencies

Towards #12735
Towards #12702

---------

Co-authored-by: cloud-java-bot <cloud-java-bot@google.com>
Co-authored-by: Mike Eltsufin <meltsufin@google.com>

Author: 3 people

.github/workflows/hermetic_library_generation.yaml

@@ -47,4 +47,5 @@ jobs:
         head_ref: ${{ github.head_ref }}
         token: ${{ secrets.CLOUD_JAVA_BOT_GITHUB_TOKEN }}
         force_regenerate_all: ${{ github.event.pull_request.head.ref == 'generate-libraries-main' }}
+        showcase_mode: true
         image_tag: ${{ env.GENERATOR_VERSION }}

.github/workflows/sdk-platform-java-ci.yaml

@@ -300,202 +300,6 @@ jobs:
         echo "All class files are compatible with Java 8."
       working-directory: sdk-platform-java
 
-  build-java8-showcase:
-    needs: filter
-    if: ${{ needs.filter.outputs.library == 'true' }}
-    name: "build(8) for showcase"
-    runs-on: ubuntu-22.04
-    steps:
-      - uses: actions/checkout@v4
-      - uses: actions/setup-java@v4
-        with:
-          java-version: 11
-          distribution: temurin
-          cache: maven
-      - name: Install all modules using Java 11
-        shell: bash
-        run: .kokoro/build.sh
-        env:
-          BUILD_SUBDIR: sdk-platform-java
-          JOB_TYPE: install
-      - uses: actions/setup-java@v3
-        with:
-          java-version: 8
-          distribution: temurin
-      - run: java -version
-      - name: Parse showcase version
-        working-directory: sdk-platform-java/java-showcase/gapic-showcase
-        run: echo "SHOWCASE_VERSION=$(mvn help:evaluate -Dexpression=gapic-showcase.version -q -DforceStdout)" >> "$GITHUB_ENV"
-      - name: Install showcase server
-        run: |
-                sudo mkdir -p /usr/src/showcase
-                sudo chown -R ${USER} /usr/src/
-                curl --location https://github.com/googleapis/gapic-showcase/releases/download/v${{env.SHOWCASE_VERSION}}/gapic-showcase-${{env.SHOWCASE_VERSION}}-linux-amd64.tar.gz --output /usr/src/showcase/showcase-${{env.SHOWCASE_VERSION}}-linux-amd64.tar.gz
-                cd /usr/src/showcase/
-                tar -xf showcase-*
-                ./gapic-showcase run &
-                cd -
-      - name: Showcase integration tests
-        working-directory: sdk-platform-java/java-showcase
-        run: |
-              mvn verify \
-                -P enable-integration-tests \
-                --batch-mode \
-                --no-transfer-progress
-        # The `slf4j1_logback` profile brings logging dependency and compiles logging tests, require env var to be set
-      - name: Showcase integration tests - Logging SLF4J 1.x
-        working-directory: sdk-platform-java/java-showcase
-        run: |
-             mvn clean verify -P '!showcase,enable-integration-tests,loggingTestBase,slf4j1_logback' \
-              --batch-mode \
-              --no-transfer-progress
-        # Set the Env Var for this step only
-        env:
-            GOOGLE_SDK_JAVA_LOGGING: true
-        # The `disabledLogging` profile tests logging disabled when logging dependency present,
-        # do not set env var for this step
-      - name: Showcase integration tests - Logging disabed
-        working-directory: sdk-platform-java/java-showcase
-        run: |
-          mvn clean verify -P '!showcase,enable-integration-tests,loggingTestBase,disabledLogging'  \
-            --batch-mode \
-            --no-transfer-progress
-      - name: Showcase integration tests - Protobuf gen code 3.25.8
-        working-directory: sdk-platform-java/java-showcase-3.25.8
-        run: |
-          mvn verify \
-            -P enable-integration-tests \
-            --batch-mode \
-            --no-transfer-progress
-      - name: Showcase integration tests - Protobuf gen code 3.21.0
-        working-directory: sdk-platform-java/java-showcase-3.21.0
-        run: |
-          mvn verify \
-            -P enable-integration-tests \
-            --batch-mode \
-            --no-transfer-progress
-  showcase:
-    needs: filter
-    if: ${{ needs.filter.outputs.library == 'true' }}
-    runs-on: ubuntu-22.04
-    strategy:
-      matrix:
-        java: [ 11, 17, 21, 25 ]
-    steps:
-      - uses: actions/checkout@v4
-      - uses: actions/setup-java@v4
-        with:
-          java-version: ${{ matrix.java }}
-          distribution: temurin
-      - run: mvn -version
-      - name: Install Maven modules
-        shell: bash
-        run: .kokoro/build.sh
-        env:
-          BUILD_SUBDIR: sdk-platform-java
-          JOB_TYPE: test      
-      - name: Showcase golden tests
-        working-directory: sdk-platform-java/java-showcase
-        run: |
-          mvn test \
-            -P enable-golden-tests \
-            --batch-mode \
-            --no-transfer-progress
-      - name: Parse showcase version
-        working-directory: sdk-platform-java/java-showcase/gapic-showcase
-        run: echo "SHOWCASE_VERSION=$(mvn help:evaluate -Dexpression=gapic-showcase.version -q -DforceStdout)" >> "$GITHUB_ENV"
-      - name: Install showcase server
-        run: |
-          sudo mkdir -p /usr/src/showcase
-          sudo chown -R ${USER} /usr/src/
-          curl --location https://github.com/googleapis/gapic-showcase/releases/download/v${{env.SHOWCASE_VERSION}}/gapic-showcase-${{env.SHOWCASE_VERSION}}-linux-amd64.tar.gz --output /usr/src/showcase/showcase-${{env.SHOWCASE_VERSION}}-linux-amd64.tar.gz
-          cd /usr/src/showcase/
-          tar -xf showcase-*
-          ./gapic-showcase run &
-          cd -
-      - name: Showcase integration tests
-        working-directory: sdk-platform-java/java-showcase
-        run: |
-          mvn verify \
-            -P enable-integration-tests \
-            --batch-mode \
-            --no-transfer-progress
-      # The `slf4j2_logback` profile brings logging dependency and compiles logging tests, require env var to be set
-      - name: Showcase integration tests - Logging SLF4J 2.x
-        working-directory: sdk-platform-java/java-showcase
-        run: |
-          mvn clean verify -P '!showcase,enable-integration-tests,loggingTestBase,slf4j2_logback' \
-            --batch-mode \
-            --no-transfer-progress
-        # Set the Env Var for this step only
-        env:
-          GOOGLE_SDK_JAVA_LOGGING: true
-    # The `slf4j1_logback` profile brings logging dependency and compiles logging tests, require env var to be set
-      - name: Showcase integration tests - Logging SLF4J 1.x
-        working-directory: sdk-platform-java/java-showcase
-        run: |
-          mvn clean verify -P '!showcase,enable-integration-tests,loggingTestBase,slf4j1_logback' \
-            --batch-mode \
-            --no-transfer-progress
-        # Set the Env Var for this step only
-        env:
-          GOOGLE_SDK_JAVA_LOGGING: true
-    # The `disabledLogging` profile tests logging disabled when logging dependency present,
-    # do not set env var for this step
-      - name: Showcase integration tests - Logging disabed
-        working-directory: sdk-platform-java/java-showcase
-        run: |
-          mvn clean verify -P '!showcase,enable-integration-tests,loggingTestBase,disabledLogging'  \
-            --batch-mode \
-            --no-transfer-progress
-      - name: Showcase integration tests - Protobuf 3 compatibility with third party library Tensorflow
-        working-directory: sdk-platform-java/java-showcase
-        run: |
-          mvn clean verify -P 'enable-integration-tests,protobuf3,showcase'  \
-            --batch-mode \
-            --no-transfer-progress
-
-  showcase-clirr:
-    needs: filter
-    if: ${{ (needs.filter.outputs.library == 'true') && github.base_ref != '' }} # Only execute on pull_request trigger event
-    runs-on: ubuntu-22.04
-    steps:
-      - name: Checkout @ target branch
-        uses: actions/checkout@v4
-        with:
-          ref: ${{ github.base_ref }}
-      - uses: actions/setup-java@v4
-        with:
-          java-version: 17
-          distribution: temurin
-          cache: maven
-      - name: Install Maven modules
-        shell: bash
-        run: .kokoro/build.sh
-        env:
-          BUILD_SUBDIR: sdk-platform-java
-          JOB_TYPE: install
-      - name: Install showcase to local maven repository
-        run: |
-          mvn install -B -ntp -T 1C -DskipTests
-          SHOWCASE_CLIENT_VERSION=$(mvn help:evaluate -Dexpression=project.version -q -DforceStdout)
-          echo "SHOWCASE_CLIENT_VERSION=$SHOWCASE_CLIENT_VERSION" >> "$GITHUB_ENV"
-        working-directory: sdk-platform-java/java-showcase
-      - name: Checkout sdk-platform-java @ PR merge commit
-        uses: actions/checkout@v3
-      - name: Install sdk-platform-java @ PR merge commit
-        shell: bash
-        run: .kokoro/build.sh
-        env:
-          JOB_TYPE: install
-          BUILD_SUBDIR: sdk-platform-java
-        # Showcase golden test ensures that src changes are already reflected in the PR.
-      - name: Clirr check
-        working-directory: sdk-platform-java/java-showcase
-        run: |
-          mvn versions:set -B -ntp -DnewVersion=local
-          mvn clirr:check -B -ntp -DcomparisonVersion=$SHOWCASE_CLIENT_VERSION
-
   gapic-generator-java-bom:
     needs: filter
     if: ${{ needs.filter.outputs.library == 'true' }}

.github/workflows/sdk-platform-java-dependency_compatibility_test.yaml

@@ -70,7 +70,7 @@ jobs:
 
       # Set up local showcase server to run the showcase ITs
       - name: Parse showcase version
-        working-directory: sdk-platform-java/java-showcase/gapic-showcase
+        working-directory: java-showcase/gapic-showcase
         run: echo "SHOWCASE_VERSION=$(mvn help:evaluate -Dexpression=gapic-showcase.version -q -DforceStdout)" >> "$GITHUB_ENV"
       - name: Install showcase server
         run: |
@@ -89,8 +89,8 @@ jobs:
         # Need to cd out of the directory to get the scripts as this step is run inside the java-showcase directory
         run: |
           if [[ -n "${{ env.DEPENDENCIES_LIST }}" ]]; then
-            ../.github/scripts/test_dependency_compatibility.sh -l ${{ env.DEPENDENCIES_LIST }}
+            ../sdk-platform-java/.github/scripts/test_dependency_compatibility.sh -l ${{ env.DEPENDENCIES_LIST }}
           else
-            ../.github/scripts/test_dependency_compatibility.sh -f ../dependencies.txt
+            ../sdk-platform-java/.github/scripts/test_dependency_compatibility.sh -f ../sdk-platform-java/dependencies.txt
           fi
-        working-directory: sdk-platform-java/java-showcase
+        working-directory: java-showcase

.github/workflows/sdk-platform-java-sonar.yaml

@@ -56,9 +56,9 @@ jobs:
       - name: Install java-showcase
         shell: bash
         run: mvn install -T 1C -DskipTests -ntp -B
-        working-directory: sdk-platform-java/java-showcase
+        working-directory: java-showcase
       - name: Parse showcase version
-        working-directory: sdk-platform-java/java-showcase/gapic-showcase
+        working-directory: java-showcase/gapic-showcase
         run: echo "SHOWCASE_VERSION=$(mvn help:evaluate -Dexpression=gapic-showcase.version -q -DforceStdout)" >> "$GITHUB_ENV"
       - name: Install showcase server
         run: |