Files
pull-request-action/pull-request.py
2024-03-11 17:27:24 -06:00

480 lines
17 KiB
Python
Executable File

#!/usr/bin/env python3
import sys
import os
import json
import requests
################################################################################
# Helper Functions
################################################################################
def get_envar(name):
"""
Given a name, return the corresponding environment variable. Exit if not
defined, as using this function indicates the envar is required.
Parameters:
name (str): the name of the environment variable
"""
value = os.environ.get(name)
if not value:
sys.exit("%s is required for vsoch/pull-request-action" % name)
return value
def check_events_json():
"""the github events json is required in order to indicate that we are
in an action environment.
"""
events = get_envar("GITHUB_EVENT_PATH")
if not os.path.exists(events):
sys.exit("Cannot find Github events file at ${GITHUB_EVENT_PATH}")
print("Found ${GITHUB_EVENT_PATH} at %s" % events)
return events
def abort_if_fail(response, reason):
"""If PASS_ON_ERROR, don't exit. Otherwise exit with an error and print
the reason.
Parameters:
response (requests.Response) : an unparsed response from requests
reason (str) : a message to print to the user for fail.
"""
message = "%s: %s: %s\n %s" % (
reason,
response.status_code,
response.reason,
response.json(),
)
if os.environ.get("PASS_ON_ERROR"):
print("Error, but PASS_ON_ERROR is set, continuing: %s" % message)
else:
sys.exit(message)
def parse_into_list(values):
"""A list of reviewers or assignees to parse from a string to a list
Parameters:
values (str) : a list of space separated, quoted values to parse to a list
"""
if values:
values = values.replace('"', "").replace("'", "")
if not values:
return []
return [x.strip() for x in values.split(" ")]
def set_env_and_output(name, value):
"""helper function to echo a key/value pair to the environement file
Parameters:
name (str) : the name of the environment variable
value (str) : the value to write to file
"""
for env_var in ("GITHUB_ENV", "GITHUB_OUTPUT"):
environment_file_path = os.environ.get(env_var)
if not environment_file_path:
print(f"Warning: {env_var} is unset, skipping.")
continue
print("Writing %s=%s to %s" % (name, value, env_var))
with open(environment_file_path, "a") as environment_file:
environment_file.write("%s=%s\n" % (name, value))
def open_pull_request(title, body, target, source, is_draft=False, can_modify=True):
"""Open pull request opens a pull request with a given body and content,
and sets output variables. An unparsed response is returned.
Parameters:
title (str) : the title to set for the new pull request
body (str) : the body to set for the new pull request
target (str) : the target branch
source (str) : the source branch
is_draft (bool) : indicate the pull request is a draft
can_modify (bool) : indicate the maintainer can modify
"""
print("No pull request from %s to %s is open, continuing!" % (source, target))
# Post the pull request
data = {
"title": title,
"body": body,
"base": target,
"head": source,
"draft": is_draft,
"maintainer_can_modify": can_modify,
}
print("Data for opening pull request: %s" % data)
response = requests.post(PULLS_URL, json=data, headers=HEADERS)
if response.status_code != 201:
print(f"pull request url is {PULLS_URL}")
abort_if_fail(response, "Unable to create pull request")
return response
def update_pull_request(entry, title, body, target, state=None):
"""Given an existing pull request, update it.
Parameters:
entry (dict) : the pull request metadata
title (str) : the title to set for the new pull request
body (str) : the body to set for the new pull request
target (str) : the target branch
state (bool) : the state of the PR (open, closed)
"""
print("PULL_REQUEST_UPDATE is set, updating existing pull request.")
data = {
"title": title,
"body": body,
"base": target,
"state": state or "open",
}
# PATCH /repos/{owner}/{repo}/pulls/{pull_number}
url = "%s/%s" % (PULLS_URL, entry.get("number"))
print("Data for updating pull request: %s" % data)
response = requests.patch(url, json=data, headers=HEADERS)
if response.status_code != 200:
abort_if_fail(response, "Unable to create pull request")
return response
def set_pull_request_groups(response):
"""Given a response for an open or updated PR, set metadata
Parameters:
response (requests.Response) : a requests response, unparsed
"""
# Expected return codes are 0 for success
pull_request_return_code = (
0 if response.status_code == 201 else response.status_code
)
response = response.json()
print("::group::github response")
print(response)
print("::endgroup::github response")
number = response.get("number")
html_url = response.get("html_url")
print("Number opened for PR is %s" % number)
set_env_and_output("PULL_REQUEST_NUMBER", number)
set_env_and_output("PULL_REQUEST_RETURN_CODE", pull_request_return_code)
set_env_and_output("PULL_REQUEST_URL", html_url)
def list_pull_requests(target, source):
"""Given a target and source, return a list of pull requests that match
(or simply exit given some kind of error code)
Parameters:
target (str) : the target branch
source (str) : the source branch
"""
# Check if the branch already has a pull request open
params = {"base": target, "head": source, "state": "open"}
print("Params for checking if pull request exists: %s" % params)
response = requests.get(PULLS_URL, params=params)
# Case 1: 401, 404 might warrant needing a token
if response.status_code in [401, 404]:
response = requests.get(PULLS_URL, params=params, headers=HEADERS)
if response.status_code != 200:
abort_if_fail(response, "Unable to retrieve information about pull requests")
return response.json()
def add_assignees(entry, assignees):
"""Given a pull request metadata (from create or update) add assignees
Parameters:
entry (dict) : the pull request metadata
assignees (str) : comma separated assignees string set by action
"""
# Remove leading and trailing quotes
assignees = parse_into_list(assignees)
number = entry.get("number")
print(
"Attempting to assign %s to pull request with number %s" % (assignees, number)
)
# POST /repos/:owner/:repo/issues/:issue_number/assignees
data = {"assignees": assignees}
ASSIGNEES_URL = "%s/%s/assignees" % (ISSUE_URL, number)
response = requests.post(ASSIGNEES_URL, json=data, headers=HEADERS)
if response.status_code != 201:
abort_if_fail(response, "Unable to create assignees")
assignees_return_code = 0 if response.status_code == 201 else response.status_code
print("::group::github assignees response")
print(response.json())
print("::endgroup::github assignees response")
set_env_and_output("ASSIGNEES_RETURN_CODE", assignees_return_code)
def find_pull_request(listing, source):
"""Given a listing and a source, find a pull request based on the source
(the branch name).
Parameters:
listing (list) : the list of PR objects (dict) to parse over
source (str) : the source (head) branch to look for
"""
if listing:
for entry in listing:
if entry.get("head", {}).get("ref", "") == source:
print("Pull request from %s is already open!" % source)
return entry
def find_default_branch():
"""Find default branch for a repo (only called if branch not provided)"""
response = requests.get(REPO_URL)
# Case 1: 401, 404 might need a token
if response.status_code in [401, 404]:
response = requests.get(REPO_URL, headers=HEADERS)
if response.status_code != 200:
abort_if_fail(response, "Unable to retrieve default branch")
default_branch = response.json()["default_branch"]
print("Found default branch: %s" % default_branch)
return default_branch
def add_reviewers(entry, reviewers, team_reviewers):
"""Given regular or team reviewers, add them to a PR.
Parameters:
entry (dict) : the pull request metadata
"""
print("Found reviewers: %s and team reviewers: %s" % (reviewers, team_reviewers))
team_reviewers = parse_into_list(team_reviewers)
reviewers = parse_into_list(reviewers)
print("Parsed reviewers: %s and team reviewers: %s" % (reviewers, team_reviewers))
# POST /repos/:owner/:repo/pulls/:pull_number/requested_reviewers
REVIEWERS_URL = "%s/%s/requested_reviewers" % (PULLS_URL, entry.get("number"))
data = {"reviewers": reviewers, "team_reviewers": team_reviewers}
response = requests.post(REVIEWERS_URL, json=data, headers=HEADERS)
if response.status_code != 201:
abort_if_fail(response, "Unable to assign reviewers")
reviewers_return_code = 0 if response.status_code == 201 else response.status_code
print("::group::github reviewers response")
print(response.json())
print("::endgroup::github reviewers response")
set_env_and_output("REVIEWERS_RETURN_CODE", reviewers_return_code)
################################################################################
# Global Variables (we can't use GITHUB_ prefix)
################################################################################
API_VERSION = "v3"
# Allow for a GitHub enterprise URL
BASE = os.environ.get("GITHUB_API_URL") or "https://api.github.com"
PR_TOKEN = os.environ.get("PULL_REQUEST_TOKEN") or get_envar("GITHUB_TOKEN")
PR_REPO = os.environ.get("PULL_REQUEST_REPOSITORY") or get_envar("GITHUB_REPOSITORY")
HEADERS = {
"Authorization": "token %s" % PR_TOKEN,
"Accept": "application/vnd.github.%s+json;application/vnd.github.antiope-preview+json;application/vnd.github.shadow-cat-preview+json"
% API_VERSION,
}
# URLs
REPO_URL = "%s/repos/%s" % (BASE, PR_REPO)
ISSUE_URL = "%s/issues" % REPO_URL
PULLS_URL = "%s/pulls" % REPO_URL
def create_pull_request(
source,
target,
body,
title,
assignees,
reviewers,
team_reviewers,
is_draft=False,
can_modify=True,
state="open",
):
"""Create pull request is the base function that determines if the PR exists,
and then updates or creates it depending on user preferences.
"""
listing = list_pull_requests(target, source)
# Determine if the pull request is already open
entry = find_pull_request(listing, source)
response = None
# Case 1: we found the PR, the user wants to pass
if entry and os.environ.get("PASS_IF_EXISTS"):
print("PASS_IF_EXISTS is set, exiting with success status.")
sys.exit(0)
# Does the user want to update the existing PR?
if entry and os.environ.get("PULL_REQUEST_UPDATE"):
response = update_pull_request(entry, title, body, target, state)
set_pull_request_groups(response)
# If it's not open, we open a new pull request
elif not entry:
response = open_pull_request(title, body, target, source, is_draft, can_modify)
set_pull_request_groups(response)
# If we have a response, parse into json (no longer need retvals)
response = response.json() if response else None
# If we have opened or updated, we can add assignees
if response and assignees:
add_assignees(response, assignees)
if response and (reviewers or team_reviewers):
add_reviewers(response, reviewers, team_reviewers)
def main():
"""main primarily parses environment variables to prepare for creation"""
# path to file that contains the POST response of the event
# Example: https://github.com/actions/bin/tree/master/debug
# Value: /github/workflow/event.json
check_events_json()
branch_prefix = os.environ.get("BRANCH_PREFIX", "")
print("Branch prefix is %s" % branch_prefix)
if not branch_prefix:
print("No branch prefix is set, all branches will be used.")
# Default to project default branch if none provided
pull_request_branch = os.environ.get("PULL_REQUEST_BRANCH")
if not pull_request_branch:
pull_request_branch = find_default_branch()
print("Pull requests will go to %s" % pull_request_branch)
# Pull request draft
pull_request_draft = os.environ.get("PULL_REQUEST_DRAFT")
if not pull_request_draft:
print("No explicit preference for draft PR: created PRs will be normal PRs.")
pull_request_draft = False
else:
print("PULL_REQUEST_DRAFT set to a value: created PRs will be draft PRs.")
pull_request_draft = True
# If an update is true, we can change the state
pull_request_state = os.environ.get("PULL_REQUEST_STATE", "open")
if pull_request_state not in ["open", "closed"]:
sys.exit("State is required to be one of 'open' or 'closed'")
# Maintainer can modify, defaults to CAN, unless user sets MAINTAINER_CANT_MODIFY
maintainer_can_modify = os.environ.get("MAINTAINER_CANT_MODIFY")
if not maintainer_can_modify:
print("No preference for maintainer being able to modify: default is true.")
maintainer_can_modify = True
else:
print(
"MAINTAINER_CANT_MODIFY set to a value: maintainer will not be able to modify."
)
maintainer_can_modify = False
# Assignees
assignees = os.environ.get("PULL_REQUEST_ASSIGNEES")
if not assignees:
print("PULL_REQUEST_ASSIGNEES is not set, no assignees.")
else:
print("PULL_REQUEST_ASSIGNEES is set, %s" % assignees)
# Reviewers (individual and team)
reviewers = os.environ.get("PULL_REQUEST_REVIEWERS")
team_reviewers = os.environ.get("PULL_REQUEST_TEAM_REVIEWERS")
if not reviewers:
print("PULL_REQUEST_REVIEWERS is not set, no reviewers.")
else:
print("PULL_REQUEST_REVIEWERS is set, %s" % reviewers)
if not team_reviewers:
print("PULL_REQUEST_TEAM_REVIEWERS is not set, no team reviewers.")
else:
print("PULL_REQUEST_TEAM_REVIEWERS is set, %s" % team_reviewers)
# The user is allowed to explicitly set the name of the branch
from_branch = os.environ.get("PULL_REQUEST_FROM_BRANCH")
if not from_branch:
print("PULL_REQUEST_FROM_BRANCH is not set, checking branch in payload.")
with open(check_events_json(), "r") as fd:
from_branch = json.loads(fd.read()).get("ref", "")
from_branch = from_branch.replace("refs/heads/", "").strip("/")
else:
print("PULL_REQUEST_FROM_BRANCH is set.")
# At this point, we must have a branch
if from_branch:
print("Found branch %s to open PR from" % from_branch)
else:
sys.exit(
"You are required to define PULL_REQUEST_FROM_BRANCH in the environment."
)
# If it's to the target branch, ignore it
if from_branch == pull_request_branch:
print("Target and current branch are identical (%s), skipping." % from_branch)
sys.exit(0)
# If the prefix for the branch matches
if not branch_prefix or from_branch.startswith(branch_prefix):
# Pull request body (optional)
pull_request_body = os.environ.get(
"PULL_REQUEST_BODY",
"This is an automated pull request to update from branch %s" % from_branch,
)
print("::group::pull request body")
print(pull_request_body)
print("::endgroup::pull request body")
# Pull request title (optional)
pull_request_title = os.environ.get(
"PULL_REQUEST_TITLE", "Update from %s" % from_branch
)
print("::group::pull request title")
print(pull_request_title)
print("::endgroup::pull request title")
# Create the pull request
create_pull_request(
target=pull_request_branch,
source=from_branch,
body=pull_request_body,
title=pull_request_title,
is_draft=pull_request_draft,
can_modify=maintainer_can_modify,
assignees=assignees,
reviewers=reviewers,
team_reviewers=team_reviewers,
state=pull_request_state,
)
if __name__ == "__main__":
print("==========================================================================")
print("START: Running Pull Request on Branch Update Action!")
main()
print("==========================================================================")
print("END: Finished")