[py] Add copybara scripts (#8368)

These are the scripts I've been using to sync between mostrobotpy and
here. I debated putting it in the "source of truth" that is
`mostrobotpy` , but I think it makes more sense here since it already
has bazel set up, and I've also recently added the ability to sync the
`commands-v2` repository, so having it all in one copybara script makes
sense.

This includes a helper python script to make it a little bit easier to
run.

shared/bazel/copybara/run_copybara.py

@@ -0,0 +1,257 @@
+import argparse
+import dataclasses
+import json
+import os
+import pathlib
+import re
+import subprocess
+from typing import Optional
+
+
+@dataclasses.dataclass
+class CopybaraConfig:
+    # Needed to run the additional updates for updating the rdev file
+    mostrobotpy_local_repo_path: Optional[str] = None
+
+    # Settings for migrating to a fork that you own
+    mostrobotpy_fork_repo: Optional[str] = None
+    allwpilib_fork_repo: Optional[str] = None
+    robotpy_commandsv2_fork_repo: Optional[str] = None
+
+    # Settings for truth repositories
+    mostrobotpy_truth_repo: str = "https://github.com/robotpy/mostrobotpy.git"
+    mostrobotpy_truth_branch: str = "2027"
+
+    allwpilib_truth_repo: str = "https://github.com/wpilibsuite/allwpilib.git"
+    allwpilib_truth_branch: str = "2027"
+
+
+def run_copybara(copybara_file: pathlib.Path, migration: str, destination_url: str):
+    args = [
+        "bazel",
+        "run",
+        "//:copybara",
+        "--",
+        "migrate",
+        str(copybara_file),
+        migration,
+        "--force",
+        "--git-destination-url",
+        destination_url,
+        "--git-destination-non-fast-forward",
+    ]
+
+    subprocess.check_call(args)
+
+
+def checkout_branch(auto_delete_branch: bool, branch_name: str):
+    """
+    This will attempt run a fetch on the repository in the cwd and checkout the given branch.
+
+    If the branch currently exists locally, it will be deleted before the fetch happens.
+    """
+    # Check if the magic branch exists locally, and if so attempt to delete it
+    ret = subprocess.call(["git", "rev-parse", "--verify", branch_name])
+    branch_exists = ret == 0
+    if branch_exists:
+        if not auto_delete_branch:
+            ans = input(f"Delete local branch {branch_name}?")
+            if ans.lower() != "y":
+                raise Exception(
+                    f"You must delete your local copy of {branch_name} before the script can finish"
+                )
+
+        subprocess.check_call(["git", "branch", "-D", branch_name])
+
+    subprocess.check_call(["git", "fetch", "--all"])
+    subprocess.check_call(["git", "checkout", branch_name])
+
+
+def update_mostrobotpy_rdev(wpilib_bin_version: str, is_development_build: bool):
+    with open("rdev.toml") as f:
+        contents = f.read()
+
+    artifactory_path = "https://frcmaven.wpi.edu/artifactory/"
+    if is_development_build:
+        artifactory_path += "development-2027"
+    else:
+        artifactory_path += "release-2027"
+
+    contents = re.sub(
+        'wpilib_bin_version = ".*"',
+        f'wpilib_bin_version = "{wpilib_bin_version}"',
+        contents,
+    )
+    contents = re.sub(
+        'wpilib_bin_url = ".*"', f'wpilib_bin_url = "{artifactory_path}"', contents
+    )
+
+    with open("rdev.toml", "w") as f:
+        f.write(contents)
+
+    subprocess.check_call(["./rdev.sh", "update-pyproject", "--commit"])
+
+
+def allwpilib_to_mostrobotpy(
+    copybara_file: pathlib.Path,
+    mostrobotpy_local_repository: str,
+    mostrobotpy_fork_repo: str,
+    wpilib_bin_version: str,
+    is_development_build: bool,
+    auto_delete_branch: bool,
+):
+    run_copybara(copybara_file, "allwpilib_to_mostrobotpy", mostrobotpy_fork_repo)
+
+    os.chdir(mostrobotpy_local_repository)
+    checkout_branch(auto_delete_branch, "copybara_allwpilib_to_mostrobotpy")
+    update_mostrobotpy_rdev(wpilib_bin_version, is_development_build)
+    subprocess.check_call(["git", "push", "-f"])
+
+
+def mostrobotpy_to_allwpilib(copybara_file: pathlib.Path, allwpilib_fork):
+    run_copybara(copybara_file, "mostrobotpy_to_allwpilib", allwpilib_fork)
+
+
+def commandsv2_to_allwpilib(copybara_file: pathlib.Path, allwpilib_fork):
+    run_copybara(copybara_file, "commandsv2_to_allwpilib", allwpilib_fork)
+
+
+def allwpilib_to_commandsv2(copybara_file: pathlib.Path, allwpilib_fork):
+    run_copybara(copybara_file, "allwpilib_to_commandsv2", allwpilib_fork)
+
+
+def load_user_config() -> CopybaraConfig:
+    script_dir = pathlib.Path(__file__).parent
+    user_config_file = script_dir / ".copybara.json"
+    if os.path.exists(user_config_file):
+        print(f"Loading user config from '{user_config_file}'")
+        with open(user_config_file, "r") as f:
+            json_config = json.load(f)
+    else:
+        print(
+            f"No user config present at '{user_config_file}', no defaults will be loaded"
+        )
+        json_config = {}
+
+    return CopybaraConfig(**json_config)
+
+
+def main():
+    user_config = load_user_config()
+
+    parser = argparse.ArgumentParser()
+    subparsers = parser.add_subparsers(
+        dest="migration", required=True, help="Available commands"
+    )
+
+    def add_allwpilib_fork_arg(subparser):
+        subparser.add_argument(
+            "--allwpilib_fork_repo",
+            default=user_config.allwpilib_fork_repo,
+            help="URL to your github fork of allwpilib that you have write permissions for",
+        )
+
+    # allwpilib -> mostrobotpy
+    allwpilib_to_mostrobotpy_parser = subparsers.add_parser(
+        "allwpilib_to_mostrobotpy",
+        help="Pushes changes from the allwpilib mirror to mostrobotpy",
+    )
+    allwpilib_to_mostrobotpy_parser.add_argument(
+        "--wpilib_bin_version",
+        required=True,
+        type=str,
+        help="The wpilib release version as hosted on artifactory",
+    )
+    allwpilib_to_mostrobotpy_parser.add_argument(
+        "--development_build",
+        action="store_true",
+        help="True if you are upgrading to a development build instead of a release build. Affects where artifacts will be downloaded from.",
+    )
+    allwpilib_to_mostrobotpy_parser.add_argument(
+        "--mostrobotpy_local_repo_path",
+        default=user_config.mostrobotpy_local_repo_path,
+        help="Path on your local computer to a mostrobotpy clone",
+    )
+    allwpilib_to_mostrobotpy_parser.add_argument(
+        "--mostrobotpy_fork_repo",
+        default=user_config.mostrobotpy_fork_repo,
+        help="URL to your github fork of mostrobotpy that you have write permissions for",
+    )
+    allwpilib_to_mostrobotpy_parser.add_argument(
+        "-y",
+        "--auto_delete_branch",
+        action="store_true",
+        help="If present, will automatically delete the local version of the copybara branch if it exists. Otherwise you will be prompted if it is ok to delete",
+    )
+
+    # mostrobotpy -> allwpilib
+    mostrobotpy_to_allwpilib_parser = subparsers.add_parser(
+        "mostrobotpy_to_allwpilib",
+        help="Pulls changes from the mostrobotpy source of truth to this mirror",
+    )
+    add_allwpilib_fork_arg(mostrobotpy_to_allwpilib_parser)
+
+    # allwpilib -> commands-v2
+    allwpilib_to_commandsv2_parser = subparsers.add_parser(
+        "allwpilib_to_commandsv2",
+        help="Pushes changes from the allwpilib mirror to the robotpy commands-v2 repo",
+    )
+    allwpilib_to_commandsv2_parser.add_argument(
+        "--robotpy_commandsv2_fork_repo",
+        default=user_config.robotpy_commandsv2_fork_repo,
+        help="URL to your github fork of mostrobotpy that you have write permissions for",
+    )
+
+    # commands-v2 -> allwpilib
+    commandsv2_to_allwpilib_parser = subparsers.add_parser(
+        "commandsv2_to_allwpilib",
+        help="Pulls changes from the robotpy commands-v2 source of truth into this mirror",
+    )
+    add_allwpilib_fork_arg(commandsv2_to_allwpilib_parser)
+
+    script_dir = pathlib.Path(__file__).parent
+    copybara_file = script_dir / "../../../copy.bara.sky"
+
+    args = parser.parse_args()
+
+    if args.migration == "allwpilib_to_mostrobotpy":
+        if args.mostrobotpy_local_repo_path is None:
+            raise Exception(
+                "You mist specify mostrobotpy_local_repo_path, either on the command line or in your user config"
+            )
+        if args.mostrobotpy_fork_repo is None:
+            raise Exception(
+                "You mist specify mostrobotpy_fork_repo, either on the command line or in your user config"
+            )
+        allwpilib_to_mostrobotpy(
+            copybara_file,
+            args.mostrobotpy_local_repo_path,
+            args.mostrobotpy_fork_repo,
+            args.wpilib_bin_version,
+            args.development_build,
+            args.auto_delete_branch,
+        )
+    elif args.migration == "mostrobotpy_to_allwpilib":
+        if args.allwpilib_fork_repo is None:
+            raise Exception(
+                "You mist specify allwpilib_fork_repo, either on the command line or in your user config"
+            )
+        mostrobotpy_to_allwpilib(copybara_file, args.allwpilib_fork_repo)
+    elif args.migration == "allwpilib_to_commandsv2":
+        if args.robotpy_commandsv2_fork_repo is None:
+            raise Exception(
+                "You mist specify robotpy_commandsv2_fork_repo, either on the command line or in your user config"
+            )
+        allwpilib_to_commandsv2(copybara_file, args.robotpy_commandsv2_fork_repo)
+    elif args.migration == "commandsv2_to_allwpilib":
+        if args.allwpilib_fork_repo is None:
+            raise Exception(
+                "You mist specify allwpilib_fork_repo, either on the command line or in your user config"
+            )
+        commandsv2_to_allwpilib(copybara_file, args.allwpilib_fork_repo)
+    else:
+        raise Exception(f"Unexpected migration {args.migration}")
+
+
+if __name__ == "__main__":
+    main()