build: add option to force regenerate all (#12619)

Adds an option to the hermetic codegen action for
`force_regenerate_all`. We set this option if the code action is running
against the `generate-libraries-main` branch.

So nightly:

1. the `.github/workflows/update_generation_config.yaml` updates the
`generate-libraries-main` branch (usually with a new
googleapis/googleapis SHA)
2. the `.github/workflows/hermetic_library_generation.yaml` runs on this
PR with the `force_regenerate_all` option enabled. This runs codegen for
all libraries, not just ones that changed between the 2
googleapis/googleapis commits.

Sample run (used this branch's name instead of
`generate-libraries-main`:
https://github.com/googleapis/google-cloud-java/actions/runs/23887924105/job/69654601450

Fixes #12319

Author: chingor13

.github/workflows/hermetic_library_generation.yaml

@@ -43,4 +43,5 @@ jobs:
         base_ref: ${{ github.base_ref }}
         head_ref: ${{ github.head_ref }}
         token: ${{ secrets.CLOUD_JAVA_BOT_GITHUB_TOKEN }}
+        force_regenerate_all: ${{ github.event.pull_request.head.ref == 'generate-libraries-main' }}
         image_tag: 2.68.1-SNAPSHOT  # {x-version-update:gapic-generator-java:current}

sdk-platform-java/.github/scripts/action.yaml

@@ -36,6 +36,9 @@ inputs:
   token:
     description: Personal Access Token
     required: true
+  force_regenerate_all:
+    description: true if we want to regenerate all libraries
+    required: false
 
 runs:
   using: "composite"
@@ -76,10 +79,12 @@ runs:
         --target_branch "${BASE_REF}" \
         --current_branch "${HEAD_REF}" \
         --showcase_mode "${SHOWCASE_MODE}" \
-        --image_tag "${IMAGE_TAG}"
+        --image_tag "${IMAGE_TAG}" \
+        --force_regenerate_all "${FORCE_REGENERATE_ALL}"
     env:
       BASE_REF: ${{ inputs.base_ref }}
       HEAD_REF: ${{ inputs.head_ref }}
       IMAGE_TAG: ${{ inputs.image_tag }}
       SHOWCASE_MODE: ${{ inputs.showcase_mode }}
       GH_TOKEN: ${{ inputs.token }}
+      FORCE_REGENERATE_ALL: ${{ inputs.force_regenerate_all }}

sdk-platform-java/.github/scripts/hermetic_library_generation.sh

@@ -50,6 +50,10 @@ case "${key}" in
     showcase_mode="$2"
     shift
     ;;
+  --force_regenerate_all)
+    force_regenerate_all="$2"
+    shift
+    ;;
   *)
     echo "Invalid option: [$1]"
     exit 1
@@ -81,6 +85,10 @@ if [ -z "${image_tag}" ]; then
   image_tag=$(grep "gapic_generator_version" "${generation_config}" | cut -d ':' -f 2 | xargs)
 fi
 
+if [ -z "${force_regenerate_all}" ]; then
+  force_regenerate_all="false"
+fi
+
 workspace_name="/workspace"
 baseline_generation_config="baseline_generation_config.yaml"
 message="chore: generate libraries at $(date)"
@@ -109,7 +117,8 @@ fi
 changed_libraries_file="$(mktemp)"
 python hermetic_build/common/cli/get_changed_libraries.py create \
   --baseline-generation-config-path="${baseline_generation_config}" \
-  --current-generation-config-path="${generation_config}" | tee "${changed_libraries_file}"
+  --current-generation-config-path="${generation_config}"\
+  --force-regenerate-all="${force_regenerate_all}" | tee "${changed_libraries_file}"
 changed_libraries="$(cat "${changed_libraries_file}")"
 echo "Changed libraries are: ${changed_libraries:-"No changed library"}."
 

sdk-platform-java/hermetic_build/common/cli/get_changed_libraries.py

@@ -21,6 +21,7 @@
 import os
 import click
 
+from common.model.config_change import ConfigChange
 from common.model.generation_config import GenerationConfig
 from common.utils.generation_config_comparator import compare_config
 
@@ -51,9 +52,18 @@ def main(ctx):
     metadata about library generation.
     """,
 )
+@click.option(
+    "--force-regenerate-all",
+    required=False,
+    type=bool,
+    help="""
+    Force regenerate all libraries.
+    """,
+)
 def create(
     baseline_generation_config_path: str,
     current_generation_config_path: str,
+    force_regenerate_all: bool,
 ) -> None:
     """
     Compares baseline generation config with current generation config and
@@ -77,6 +87,7 @@ def create(
     config_change = compare_config(
         baseline_config=GenerationConfig.from_yaml(baseline_generation_config_path),
         current_config=GenerationConfig.from_yaml(current_generation_config_path),
+        force_regenerate_all=force_regenerate_all,
     )
     click.echo(",".join(config_change.get_changed_libraries()))
 

sdk-platform-java/hermetic_build/common/utils/generation_config_comparator.py

@@ -25,7 +25,9 @@
 
 
 def compare_config(
-    baseline_config: GenerationConfig, current_config: GenerationConfig
+    baseline_config: GenerationConfig,
+    current_config: GenerationConfig,
+    force_regenerate_all: bool = False,
 ) -> ConfigChange:
     """
     Compare two GenerationConfig object and output a mapping from ConfigChange
@@ -48,6 +50,12 @@ def compare_config(
     current_params = __convert_params_to_sorted_list(
         obj=current_config, excluded_params=excluded_params
     )
+    if force_regenerate_all:
+        config_change = LibraryChange(
+            changed_param="force_regenerate_all",
+            current_value="true",
+        )
+        diff[ChangeType.REPO_LEVEL_CHANGE].append(config_change)
 
     for baseline_param, current_param in zip(baseline_params, current_params):
         if baseline_param == current_param:
@@ -60,7 +68,6 @@ def compare_config(
                 current_value=current_param[1],
             )
             diff[ChangeType.REPO_LEVEL_CHANGE].append(config_change)
-
     __compare_libraries(
         diff=diff,
         baseline_library_configs=baseline_config.libraries,