eden cli: Refactor handler.exe code a bit

Summary:
This diff moves the code that manages handler.exe to its own module and abstract the functionality into a base class, even though for now only Windows is implemented.

It also calls this new handle in the branch that deletes a non-Eden directory, because it's very convenient to test.

Reviewed By: genevievehelsel

Differential Revision: D53594227

fbshipit-source-id: 309efab3f89893f745a82fe5acd128ecd702d42e

eden/fs/cli/TARGETS

@@ -141,6 +141,7 @@ python_library(
         "doctor/facebook/lib/fake_vscode_extensions_checker.py",
         "doctor/problem.py",
         "doctor/util.py",
+        "file_handler_tools.py",
         "filesystem.py",
         "hg_util.py",
         "logfile.py",

eden/fs/cli/config.py

@@ -44,6 +44,7 @@ from facebook.eden.ttypes import MountInfo as ThriftMountInfo, MountState
 from filelock import BaseFileLock, FileLock
 
 from . import configinterpolator, configutil, telemetry, util, version
+from .file_handler_tools import WinFileHandlerReleaser
 from .util import (
     FUSE_MOUNT_PROTOCOL_STRING,
     HealthStatus,
@@ -862,51 +863,6 @@ Do you want to run `eden mount %s` instead?"""
         with self.get_thrift_client_legacy(timeout=60) as client:
             client.unmount(os.fsencode(path))
 
-    def get_handle_path(self) -> Optional[Path]:
-        handle = shutil.which("handle.exe")
-        if handle:
-            return Path(handle)
-        return None
-
-    def check_handle(self, mount: Path) -> None:
-        handle = self.get_handle_path()
-
-        if not handle:
-            return
-
-        print(f"Checking handle.exe for processes using '{mount}'...")
-        print("Press ctrl+c to skip.")
-        try:
-            output = subprocess.check_output(
-                [handle, "-nobanner", "-accepteula", mount]
-            )
-        except KeyboardInterrupt:
-            print("Handle check interrupted.\n")
-            print("If you want to find out which process is still using the repo, run:")
-            print(f"    handle.exe {mount}\n")
-            return
-        parsed = [
-            line.split() for line in output.decode(errors="ignore").splitlines() if line
-        ]
-        non_edenfs_process = any(filter(lambda x: x[0].lower() != "edenfs.exe", parsed))
-
-        # When no handle is found in the repo, handle.exe will report `"No
-        # matching handles found."`, which will be 4 words.
-        if not non_edenfs_process or not parsed or len(parsed[0]) == 4:
-            # Nothing other than edenfs.exe is holding handles to files from
-            # the repo, we can proceed with the removal
-            return
-
-        print(
-            "The following processes are still using the repo, please terminate them.\n"
-        )
-
-        for executable, _, pid, _, _type, _, path in parsed:
-            print(f"{executable}({pid}): {path}")
-
-        print()
-        return
-
     def destroy_mount(
         self, path: Union[Path, str], preserve_mount_point: bool = False
     ) -> None:
@@ -1007,22 +963,8 @@ trouble cleaning up leftovers. You will need to manually remove {path}.
             )
 
             if used_by_other:
-                if self.get_handle_path():
+                winhr = WinFileHandlerReleaser()
-                    self.check_handle(path)
+                winhr.try_release(path)
-                else:
-                    print(
-                        f"""\
-    It looks like {path} is still in use by another process. If you need help to
-    figure out which process, please try `handle.exe` from sysinternals:
-
-    handle.exe {path}
-
-    """
-                    )
-                print(
-                    f"After terminating the processes, please manually delete {path}."
-                )
-                print()
 
             raise errors[0][1]
 

eden/fs/cli/file_handler_tools.py

@@ -0,0 +1,106 @@
+#!/usr/bin/env python3
+# Copyright (c) Meta Platforms, Inc. and affiliates.
+#
+# This software may be used and distributed according to the terms of the
+# GNU General Public License version 2.
+
+# pyre-strict
+
+import shutil
+import subprocess
+import sys
+from abc import ABC, abstractmethod
+from pathlib import Path
+from typing import Optional
+
+WINDOWS_HANDLE_BIN = "handle.exe"
+
+
+class FileHandlerReleaser(ABC):
+    @abstractmethod
+    def get_handle_path(self) -> Optional[Path]:
+        """Returns the path to the handle tool if it exists on the system, such as handle.exe on Windows or lsof on Linux."""
+        pass
+
+    @abstractmethod
+    def check_handle(self, mount: Path) -> None:
+        """Displays processes keeping an open handle to files and if possible, offers to terminate them."""
+        pass
+
+    @abstractmethod
+    def try_release(self, mount: Path) -> None:
+        """If a handle tool exist, use it to display info to the user with check handle."""
+        pass
+
+
+class WinFileHandlerReleaser(FileHandlerReleaser):
+    def get_handle_path(self) -> Optional[Path]:
+        if sys.platform != "win32":
+            return None
+
+        handle = shutil.which(WINDOWS_HANDLE_BIN)
+        if handle:
+            return Path(handle)
+        return None
+
+    def check_handle(self, mount: Path) -> None:
+        handle = self.get_handle_path()
+
+        if not handle:
+            return
+
+        print(
+            f"Checking handle.exe for processes using '{mount}'. This can take a while..."
+        )
+        print("Press ctrl+c to skip.")
+        try:
+            output = subprocess.check_output(
+                [
+                    handle,
+                    "-nobanner",
+                    "/accepteula",
+                    mount,
+                ]  # / vs - is importart for accepteula, otherwise it won't find handles (??)
+            )
+        except KeyboardInterrupt:
+            print("Handle check interrupted.\n")
+            print("If you want to find out which process is still using the repo, run:")
+            print(f"    handle.exe {mount}\n")
+            return
+        parsed = [
+            line.split() for line in output.decode(errors="ignore").splitlines() if line
+        ]
+        non_edenfs_process = any(filter(lambda x: x[0].lower() != "edenfs.exe", parsed))
+
+        # When no handle is found in the repo, handle.exe will report `"No
+        # matching handles found."`, which will be 4 words.
+        if not non_edenfs_process or not parsed or len(parsed[0]) == 4:
+            # Nothing other than edenfs.exe is holding handles to files from
+            # the repo, we can proceed with the removal
+            return
+
+        print(
+            "The following processes are still using the repo, please terminate them.\n"
+        )
+
+        for executable, _, pid, _, _type, _, path in parsed:
+            print(f"{executable}({pid}): {path}")
+
+        print()
+        return
+
+    def try_release(self, mount: Path) -> None:
+        if self.get_handle_path():
+            self.check_handle(mount)
+        else:
+            print(
+                f"""\
+It looks like {mount} is still in use by another process. If you need help to
+figure out which process, please try `handle.exe` from sysinternals:
+
+handle.exe {mount}
+
+"""
+            )
+        print(f"After terminating the processes, please manually delete {mount}.")
+        print()

eden/fs/cli/main.py

@@ -78,6 +78,7 @@ from .constants import (
     SHUTDOWN_EXIT_CODE_REQUESTED_SHUTDOWN,
     SHUTDOWN_EXIT_CODE_TERMINATED_VIA_SIGKILL,
 )
+from .file_handler_tools import WinFileHandlerReleaser
 from .stats_print import format_size
 from .subcmd import Subcmd
 from .util import get_environment_suitable_for_subprocess, print_stderr, ShutdownError
@@ -1599,8 +1600,15 @@ Do you still want to delete {path}?"""
                                     path.rmdir()
                                 return 0
                             except Exception as ex:
-                                print(f"error: cannot remove contents of {path}: {ex}")
+                                if sys.platform != "win32":
-                                return 1
+                                    print(
+                                        f"Error: cannot remove contents of {path}: {ex}"
+                                    )
+                                    return 1
+                                else:
+                                    winhr = WinFileHandlerReleaser()
+                                    winhr.try_release(path)
+                                    return 0
                     else:
                         # We can't ask the user what their true intentions are,
                         # so let's fail by default.