Add SUBPROJECT_ID setting

README.md

@@ -327,14 +327,25 @@ jobs:
     COMMENT_ARTIFACT_NAME: python-coverage-comment-action
 
     # Name of the file in which the body of the comment to post on the PR is stored.
-    # You typically don't have to change this unless you're already using this name for something else.
+    # In monorepo setting, see SUBPROJECT_ID.
     COMMENT_FILENAME: python-coverage-comment-action.txt
 
+    # This setting is only necessary if you plan to run the action multiple times
+    # in the same repository. It will be appended to the value of all the
+    # settings that need to be unique, so as for the action to avoid mixing
+    # up results of multiple runs.
+    # Affects `COMMENT_FILENAME`, `COVERAGE_DATA_BRANCH`.
+    # Ideally, use dashes (`-`) rather than underscrores (`_`) to split words,
+    # for consistency
+    SUBPROJECT_ID: null / "lib-name"
+
     # An alternative template for the comment for pull requests. See details below.
     COMMENT_TEMPLATE: The coverage rate is `{{ coverage.info.percent_covered | pct }}`{{ marker }}
 
     # Name of the branch in which coverage data will be stored on the repository.
-    # Please make sure that this branch is not protected.
+    # Default is 'python-coverage-comment-action-data'. Please make sure that this
+    # branch is not protected.
+    # In monorepo setting, see SUBPROJECT_ID.
     COVERAGE_DATA_BRANCH: python-coverage-comment-action-data
 
     # Deprecated, see https://docs.github.com/en/actions/monitoring-and-troubleshooting-workflows/enabling-debug-logging
@@ -383,6 +394,103 @@ coverage (percentage) of the whole project from the PR build:
 "Coverage: {{ coverage.info.percent_covered | pct }}{{ marker }}"
 ```
 
+## Monorepo setting
+
+In case you want to use the action multiple times with different parts of your
+source (so you have multiple codebases into a single repo), you'll
+need to use SUBPROJECT_ID with a different value for each launch. You may
+still use the same step for storing all files as artifacts. You'll end up with
+a different comment for each launch. Feel free to use the `COMMENT_TEMPLATE` if
+you want each comment to clearly state what it relates to.
+
+```yaml
+# .github/workflows/ci.yml
+name: CI
+
+on:
+  pull_request:
+  push:
+    branches:
+      - "main"
+
+jobs:
+  test:
+    name: Run tests & display coverage
+    runs-on: ubuntu-latest
+    permissions:
+      pull-requests: write
+      contents: write
+    steps:
+      - uses: actions/checkout@v3
+
+      - name: Test project 1
+        run: make -C project_1 test
+
+      - name: Test project 2
+        run: make -C project_2 test
+
+      - name: Coverage comment (project 1)
+        id: coverage_comment
+        uses: py-cov-action/python-coverage-comment-action@v3
+        with:
+          COVERAGE_PATH: project_1
+          SUBPROJECT_ID: project-1
+          GITHUB_TOKEN: ${{ github.token }}
+
+      - name: Coverage comment (project 2)
+        id: coverage_comment
+        uses: py-cov-action/python-coverage-comment-action@v3
+        with:
+          COVERAGE_PATH: project_2/src
+          SUBPROJECT_ID: project-2
+          GITHUB_TOKEN: ${{ github.token }}
+
+      - name: Store Pull Request comment to be posted
+        uses: actions/upload-artifact@v3
+        if: steps.coverage_comment.outputs.COMMENT_FILE_WRITTEN == 'true'
+        with:
+          name: python-coverage-comment-action
+          # Note the star
+          path: python-coverage-comment-action*.txt
+```
+
+```yaml
+# .github/workflows/coverage.yml
+name: Post coverage comment
+
+on:
+  workflow_run:
+    workflows: ["CI"]
+    types:
+      - completed
+
+jobs:
+  test:
+    name: Run tests & display coverage
+    runs-on: ubuntu-latest
+    if: github.event.workflow_run.event == 'pull_request' && github.event.workflow_run.conclusion == 'success'
+    permissions:
+      pull-requests: write
+      contents: write
+      actions: read
+    steps:
+      - name: Post comment
+        uses: py-cov-action/python-coverage-comment-action@v3
+        with:
+          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+          GITHUB_PR_RUN_ID: ${{ github.event.workflow_run.id }}
+          SUBPROJECT_ID: project-1
+          COVERAGE_PATH: project_1
+
+      - name: Post comment
+        uses: py-cov-action/python-coverage-comment-action@v3
+        with:
+          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+          GITHUB_PR_RUN_ID: ${{ github.event.workflow_run.id }}
+          SUBPROJECT_ID: project-2
+          COVERAGE_PATH: project_2/src
+```
+
 # Other topics
 
 ## Pinning

action.yml

@@ -27,6 +27,7 @@ inputs:
       Name of the branch in which coverage data will be stored on the repository.
       Default is 'python-coverage-comment-action-data'. Please make sure that this
       branch is not protected.
+      In monorepo setting, see SUBPROJECT_ID.
     default: python-coverage-comment-action-data
     required: false
   COVERAGE_PATH:
@@ -38,13 +39,25 @@ inputs:
   COMMENT_ARTIFACT_NAME:
     description: >
       Name of the artifact in which the body of the comment to post on the PR is stored.
+      You typically don't have to change this unless you're already using this name for something else.
     default: python-coverage-comment-action
     required: false
   COMMENT_FILENAME:
     description: >
       Name of the file in which the body of the comment to post on the PR is stored.
+      In monorepo setting, see SUBPROJECT_ID.
     default: python-coverage-comment-action.txt
     required: false
+  SUBPROJECT_ID:
+    description: >
+      This setting is only necessary if you plan to run the action multiple
+      times in the same repository. It will be appended to the value of all the
+      settings that need to be unique, so as for the action to avoid mixing up
+      results of multiple runs. Ideally, use dashes (`-`) rather than
+      underscrores (`_`) to split words, for consistency.
+      Affects `COMMENT_FILENAME`, `COVERAGE_DATA_BRANCH`.
+    default: null
+    required: false
   MINIMUM_GREEN:
     description: >
       If the coverage percentage is above or equal to this value, the badge
@@ -67,7 +80,7 @@ inputs:
     default: false
   ANNOTATION_TYPE:
     description: >
-      Only needed if ANNOTATE_MISSING_LINES is set to true. This parameter allows you to choose between
+      Only relevant if ANNOTATE_MISSING_LINES is set to true. This parameter allows you to choose between
       notice, warning and error as annotation type. For more information look here:
       https://docs.github.com/en/actions/using-workflows/workflow-commands-for-github-actions#setting-a-notice-message
     default: warning
@@ -78,8 +91,11 @@ inputs:
 outputs:
   COMMENT_FILE_WRITTEN:
     description: >
-      If "true", a comment file was written to COMMENT_FILENAME. If "false",
-      no comment file was written (because the comment was already posted).
+      This output is only set when running in PR mode.It's a boolean indicating
+      whether a comment file was written to COMMENT_FILENAME or not. If so,
+      you'll need to run the action in workflow_run mode to post it. If
+      "false", no comment file was written (likely because the comment was
+      already posted to the PR).
 runs:
   using: docker
   image: Dockerfile
@@ -91,6 +107,7 @@ runs:
     COVERAGE_PATH: ${{ inputs.COVERAGE_PATH }}
     COMMENT_ARTIFACT_NAME: ${{ inputs.COMMENT_ARTIFACT_NAME }}
     COMMENT_FILENAME: ${{ inputs.COMMENT_FILENAME }}
+    SUBPROJECT_ID: ${{ inputs.SUBPROJECT_ID }}
     MINIMUM_GREEN: ${{ inputs.MINIMUM_GREEN }}
     MINIMUM_ORANGE: ${{ inputs.MINIMUM_ORANGE }}
     MERGE_COVERAGE_FILES: ${{ inputs.MERGE_COVERAGE_FILES }}

coverage_comment/github.py

@@ -113,7 +113,7 @@ def get_pr_number_from_workflow_run(
         raise CannotDeterminePR(f"No open PR found for branch {full_branch}")
 
 
-def get_my_login(github: github_client.GitHub):
+def get_my_login(github: github_client.GitHub) -> str:
     try:
         response = github.user.get()
     except github_client.Forbidden:

coverage_comment/main.py

@@ -120,19 +120,22 @@ def generate_comment(
     previous_coverage_data_file = storage.get_datafile_contents(
         github=gh,
         repository=config.GITHUB_REPOSITORY,
-        branch=config.COVERAGE_DATA_BRANCH,
+        branch=config.FINAL_COVERAGE_DATA_BRANCH,
     )
     previous_coverage = None
     if previous_coverage_data_file:
         previous_coverage = files.parse_datafile(contents=previous_coverage_data_file)
 
+    marker = template.get_marker(marker_id=config.SUBPROJECT_ID)
     try:
         comment = template.get_comment_markdown(
             coverage=coverage,
             diff_coverage=diff_coverage,
             previous_coverage_rate=previous_coverage,
             base_template=template.read_template_file("comment.md.j2"),
             custom_template=config.COMMENT_TEMPLATE,
+            marker=marker,
+            subproject_id=config.SUBPROJECT_ID,
         )
     except template.MissingMarker:
         log.error(
@@ -167,7 +170,7 @@ def generate_comment(
             repository=config.GITHUB_REPOSITORY,
             pr_number=config.GITHUB_PR_NUMBER,
             contents=comment,
-            marker=template.MARKER,
+            marker=marker,
         )
     except github.CannotPostComment:
         log.debug("Exception when posting comment", exc_info=True)
@@ -178,7 +181,7 @@ def generate_comment(
             "on PR comments for external PRs)."
         )
         comment_file.store_file(
-            filename=config.COMMENT_FILENAME,
+            filename=config.FINAL_COMMENT_FILENAME,
             content=comment,
         )
         github.set_output(github_output=config.GITHUB_OUTPUT, COMMENT_FILE_WRITTEN=True)
@@ -224,7 +227,7 @@ def post_comment(config: settings.Config, github_session: httpx.Client) -> int:
             repository=config.GITHUB_REPOSITORY,
             artifact_name=config.COMMENT_ARTIFACT_NAME,
             run_id=config.GITHUB_PR_RUN_ID,
-            filename=config.COMMENT_FILENAME,
+            filename=config.FINAL_COMMENT_FILENAME,
         )
     except github.NoArtifact:
         log.info(
@@ -240,7 +243,7 @@ def post_comment(config: settings.Config, github_session: httpx.Client) -> int:
         repository=config.GITHUB_REPOSITORY,
         pr_number=pr_number,
         contents=comment,
-        marker=template.MARKER,
+        marker=template.get_marker(marker_id=config.SUBPROJECT_ID),
     )
     log.info("Comment posted in PR")
 
@@ -294,14 +297,14 @@ def save_coverage_data_files(
         storage.get_raw_file_url,
         is_public=is_public,
         repository=config.GITHUB_REPOSITORY,
-        branch=config.COVERAGE_DATA_BRANCH,
+        branch=config.FINAL_COVERAGE_DATA_BRANCH,
     )
     readme_url = storage.get_repo_file_url(
-        branch=config.COVERAGE_DATA_BRANCH,
+        branch=config.FINAL_COVERAGE_DATA_BRANCH,
         repository=config.GITHUB_REPOSITORY,
     )
     html_report_url = storage.get_html_report_url(
-        branch=config.COVERAGE_DATA_BRANCH,
+        branch=config.FINAL_COVERAGE_DATA_BRANCH,
         repository=config.GITHUB_REPOSITORY,
     )
     readme_file, log_message = communication.get_readme_and_log(
@@ -315,7 +318,7 @@ def save_coverage_data_files(
     storage.commit_operations(
         operations=operations,
         git=git,
-        branch=config.COVERAGE_DATA_BRANCH,
+        branch=config.FINAL_COVERAGE_DATA_BRANCH,
     )
 
     log.info(log_message)

coverage_comment/settings.py

@@ -45,6 +45,7 @@ class Config:
     COVERAGE_PATH: pathlib.Path = pathlib.Path(".")
     COMMENT_ARTIFACT_NAME: str = "python-coverage-comment-action"
     COMMENT_FILENAME: pathlib.Path = pathlib.Path("python-coverage-comment-action.txt")
+    SUBPROJECT_ID: str | None = None
     GITHUB_OUTPUT: pathlib.Path | None = None
     MINIMUM_GREEN: decimal.Decimal = decimal.Decimal("100")
     MINIMUM_ORANGE: decimal.Decimal = decimal.Decimal("70")
@@ -119,6 +120,21 @@ def GITHUB_PR_NUMBER(self) -> int | None:
             return int(self.GITHUB_REF.split("/")[2])
         return None
 
+    @property
+    def FINAL_COMMENT_FILENAME(self):
+        filename = self.COMMENT_FILENAME
+        if self.SUBPROJECT_ID:
+            new_name = f"{filename.stem}-{self.SUBPROJECT_ID}{filename.suffix}"
+            return filename.parent / new_name
+        return filename
+
+    @property
+    def FINAL_COVERAGE_DATA_BRANCH(self):
+        parts = [self.COVERAGE_DATA_BRANCH]
+        if self.SUBPROJECT_ID:
+            parts.append(self.SUBPROJECT_ID)
+        return "-".join(parts)
+
     # We need to type environ as a MutableMapping because that's what
     # os.environ is, and just saying `dict[str, str]` is not enough to make
     # mypy happy

coverage_comment/template.py

@@ -7,7 +7,9 @@
 
 from coverage_comment import coverage as coverage_module
 
-MARKER = """<!-- This comment was produced by python-coverage-comment-action -->"""
+MARKER = (
+    """<!-- This comment was produced by python-coverage-comment-action{id_part} -->"""
+)
 
 
 def uptodate():
@@ -39,11 +41,17 @@ class TemplateError(Exception):
     pass
 
 
+def get_marker(marker_id: str | None):
+    return MARKER.format(id_part=f" (id: {marker_id})" if marker_id else "")
+
+
 def get_comment_markdown(
     coverage: coverage_module.Coverage,
     diff_coverage: coverage_module.DiffCoverage,
     previous_coverage_rate: decimal.Decimal | None,
     base_template: str,
+    marker: str,
+    subproject_id: str | None = None,
     custom_template: str | None = None,
 ):
     loader = CommentLoader(base_template=base_template, custom_template=custom_template)
@@ -55,12 +63,13 @@ def get_comment_markdown(
             previous_coverage_rate=previous_coverage_rate,
             coverage=coverage,
             diff_coverage=diff_coverage,
-            marker=MARKER,
+            subproject_id=subproject_id,
+            marker=marker,
         )
     except jinja2.exceptions.TemplateError as exc:
         raise TemplateError from exc
 
-    if MARKER not in comment:
+    if marker not in comment:
         raise MissingMarker()
 
     return comment

coverage_comment/template_files/comment.md.j2

@@ -1,4 +1,4 @@
-{% block title %}## Coverage report{% endblock title %}
+{% block title %}## Coverage report{% if subproject_id %} ({{ subproject_id  }}){% endif %}{% endblock title %}
 {% block coverage_evolution -%}
 {% if previous_coverage_rate -%}
 {% block coverage_evolution_wording -%}