Merge pull request #10 from Magnus167/prchecks

Add checks for validating merge conditions

.github/scripts/pr_checks.py

@@ -0,0 +1,236 @@
+import os
+import sys
+import urllib.request
+import urllib.error
+import json
+from typing import Any, Dict, List, Optional, Tuple
+import warnings
+import urllib.parse
+
+from time import sleep
+
+sys.path.append(os.getcwd())
+
+ACCESS_TOKEN: Optional[str] = os.getenv("GH_TOKEN", None)
+
+REQUEST_CONFIG = {
+    "Accept": "application/vnd.github.v3+json",
+    "Authorization": f"token {ACCESS_TOKEN}",
+    "X-GitHub-Api-Version": "2022-11-28",
+}
+REPO_OWNER_USERNAME: str = "Magnus167"
+REPO_NAME: str = "rustframe"
+REPOSITORY_WEB_LINK: str = f"github.com/{REPO_OWNER_USERNAME}/{REPO_NAME}"
+
+
+def perform_api_call(
+    target_url: str,
+    call_headers: Optional[dict] = REQUEST_CONFIG,
+    query_parameters: Dict[str, Any] = {},
+    http_method: str = "GET",
+    maximum_attempts: int = 5,
+) -> Any:
+    assert http_method in ["GET", "DELETE", "POST", "PATCH", "PUT"]
+
+    attempt_count = 0
+    while attempt_count < maximum_attempts:
+        try:
+            if query_parameters:
+                encoded_parameters = urllib.parse.urlencode(query_parameters)
+                target_url = f"{target_url}?{encoded_parameters}"
+
+            http_request_object = urllib.request.Request(target_url, method=http_method)
+
+            if call_headers:
+                for key, value in call_headers.items():
+                    http_request_object.add_header(key, value)
+
+            with urllib.request.urlopen(http_request_object) as server_response:
+                if server_response.status == 404:
+                    raise Exception(f"404: {target_url} not found.")
+
+                return json.loads(server_response.read().decode())
+
+        except urllib.error.HTTPError as error_details:
+            unrecoverable_codes = [403, 404, 422]
+            if error_details.code in unrecoverable_codes:
+                raise Exception(f"Request failed: {error_details}")
+
+            print(f"Request failed: {error_details}")
+            attempt_count += 1
+            sleep(1)
+
+        except Exception as error_details:
+            print(f"Request failed: {error_details}")
+            attempt_count += 1
+            sleep(1)
+
+    raise Exception("Request failed")
+
+
+valid_title_prefixes: List[str] = [
+    "Feature:",
+    "Bugfix:",
+    "Documentation:",
+    "CI/CD:",
+    "Misc:",
+    "Suggestion:",
+]
+
+
+def validate_title_format(
+    item_title: str,
+) -> bool:
+    estr = "Skipping PR title validation"
+    for _ in range(5):
+        warnings.warn(estr)
+        print(estr)
+    return True
+
+    is_format_correct: bool = False
+    for prefix_pattern in valid_title_prefixes:
+        cleaned_input: str = item_title.strip()
+        if cleaned_input.startswith(prefix_pattern):
+            is_format_correct = True
+            break
+
+    if not is_format_correct:
+        issue_message: str = (
+            f"PR title '{item_title}' does not match any "
+            f"of the accepted patterns: {valid_title_prefixes}"
+        )
+        raise ValueError(issue_message)
+
+    return is_format_correct
+
+
+def _locate_segment_indices(
+    content_string: str,
+    search_pattern: str,
+    expect_numeric_segment: bool = False,
+) -> Tuple[int, int]:
+    numeric_characters: List[str] = list(map(str, range(10))) + ["."]
+    assert bool(content_string)
+    assert bool(search_pattern)
+    assert search_pattern in content_string
+    start_index: int = content_string.find(search_pattern)
+    end_index: int = content_string.find("-", start_index)
+    if end_index == -1 and not expect_numeric_segment:
+        return (start_index, len(content_string))
+
+    if expect_numeric_segment:
+        start_index = start_index + len(search_pattern)
+        for char_index, current_character in enumerate(content_string[start_index:]):
+            if current_character not in numeric_characters:
+                break
+        end_index = start_index + char_index
+
+    return (start_index, end_index)
+
+
+def _verify_no_merge_flag(
+    content_string: str,
+) -> bool:
+    assert bool(content_string)
+    return "DO-NOT-MERGE" not in content_string
+
+
+def _verify_merge_dependency(
+    content_string: str,
+) -> bool:
+    assert bool(content_string)
+    dependency_marker: str = "MERGE-AFTER-#"
+
+    if dependency_marker not in content_string:
+        return True
+
+    start_index, end_index = _locate_segment_indices(
+        content_string=content_string, pattern=dependency_marker, numeric=True
+    )
+    dependent_item_id: str = content_string[start_index:end_index].strip()
+    try:
+        dependent_item_id = int(dependent_item_id)
+    except ValueError:
+        issue_message: str = f"PR number '{dependent_item_id}' is not an integer."
+        raise ValueError(issue_message)
+
+    dependent_item_data: Dict[str, Any] = fetch_item_details(
+        item_identifier=dependent_item_id
+    )
+    is_dependent_item_closed: bool = dependent_item_data["state"] == "closed"
+    return is_dependent_item_closed
+
+
+def evaluate_merge_conditions(
+    item_details: Dict[str, Any],
+) -> bool:
+    item_body_content: str = item_details["body"]
+
+    if item_body_content is None:
+        return True
+
+    item_body_content = item_body_content.strip().replace(" ", "-").upper()
+    item_body_content = f" {item_body_content} "
+
+    condition_outcomes: List[bool] = [
+        _verify_no_merge_flag(content_string=item_body_content),
+        _verify_merge_dependency(content_string=item_body_content),
+    ]
+
+    return all(condition_outcomes)
+
+
+def validate_item_for_merge(
+    item_data: Dict[str, Any],
+) -> bool:
+    assert set(["number", "title", "state", "body"]).issubset(item_data.keys())
+    accumulated_issues: str = ""
+    if not validate_title_format(item_title=item_data["title"]):
+        accumulated_issues += (
+            f"PR #{item_data['number']} is not mergable due to invalid title.\n"
+        )
+
+    if not evaluate_merge_conditions(item_details=item_data):
+        accumulated_issues += (
+            f"PR #{item_data['number']} is not mergable due to merge restrictions"
+            " specified in the PR body."
+        )
+
+    if accumulated_issues:
+        raise ValueError(accumulated_issues.strip())
+
+    return True
+
+
+def fetch_item_details(
+    item_identifier: int,
+):
+    api_request_url: str = f"https://api.github.com/repos/{REPO_OWNER_USERNAME}/{REPO_NAME}/pulls/{item_identifier}"
+
+    raw_api_response_data: Dict[str, Any] = perform_api_call(target_url=api_request_url)
+
+    extracted_item_info: Dict[str, Any] = {
+        "number": raw_api_response_data["number"],
+        "title": raw_api_response_data["title"],
+        "state": raw_api_response_data["state"],
+        "body": raw_api_response_data["body"],
+    }
+
+    return extracted_item_info
+
+
+def process_item_request(requested_item_id: int):
+    extracted_item_info: Dict[str, Any] = fetch_item_details(
+        item_identifier=requested_item_id
+    )
+    if not validate_item_for_merge(item_data=extracted_item_info):
+        raise ValueError("PR is not mergable.")
+
+    print("PR is mergable.")
+
+    return True
+
+
+if __name__ == "__main__":
+    requested_item_id: int = int(sys.argv[1])
+    process_item_request(requested_item_id=requested_item_id)

.github/workflows/pr-checks.yml

@@ -0,0 +1,29 @@
+name: pr-checks
+
+on:
+  pull_request:
+    branches: [main]
+    types: [opened, synchronize, reopened, edited, ready_for_review]
+
+concurrency:
+  group: pr-checks-${{ github.event.number }}
+
+permissions:
+  contents: read
+  pull-requests: read
+  checks: write
+
+jobs:
+  pr-checks:
+    name: pr-checks
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+
+      - name: Run PR checks
+        shell: bash
+        env:
+          GH_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+          PR_NUMBER: ${{ github.event.number }}
+        run: |
+          python .github/scripts/pr_checks.py $PR_NUMBER