add an eden remove command

Summary:
Add a `remove` command to the Eden CLI.  This behaves like
`eden unmount --destroy`, but calling this "remove" is hopefully a more
intuitive UI.  If stdin is a TTY this command also prompts the user for
confirmation before removing the checkout.

I plan to deprecate the `eden unmount --destroy` command in a subsequent
diff.

Reviewed By: wez

Differential Revision: D8086823

fbshipit-source-id: 562cf0f998eea416b80589b188eee255a10b9699

eden/cli/main.py

@@ -12,12 +12,14 @@ import errno
 import glob
 import json
 import os
+import readline  # noqa: F401 Importing readline improves the behavior of input()
 import signal
 import subprocess
 import sys
 import typing
 from typing import Any, List, Optional, Set, Tuple
 
+import eden.thrift
 from eden.thrift import EdenNotRunningError
 from facebook.eden import EdenService
 
@@ -71,7 +73,7 @@ def do_version(args: argparse.Namespace) -> int:
         print("Running:   %s" % rv)
         if rv.startswith("-") or rv.endswith("-"):
             print("(Dev version of eden seems to be running)")
-    except eden.thrift.client.EdenNotRunningError:
+    except EdenNotRunningError:
         print("Running:   Unknown (edenfs does not appear to be running)")
     return 0
 
@@ -445,6 +447,66 @@ class MountCmd(Subcmd):
         return 0
 
 
+@subcmd("remove", "Remove an eden checkout", aliases=["rm"])
+class RemoveCmd(Subcmd):
+
+    def setup_parser(self, parser: argparse.ArgumentParser) -> None:
+        parser.add_argument(
+            "-y",
+            "--yes",
+            "--no-prompt",
+            dest="prompt",
+            default=True,
+            action="store_false",
+            help="Do not prompt for confirmation before removing the checkouts.",
+        )
+        parser.add_argument(
+            "paths", nargs="+", metavar="path", help="The Eden checkout(s) to remove"
+        )
+
+    def run(self, args: argparse.Namespace) -> int:
+        config = create_config(args)
+
+        # First translate the list of paths into mount point names
+        mounts = []
+        for path in args.paths:
+            try:
+                mount_path = util.get_eden_mount_name(path)
+            except util.NotAnEdenMountError as ex:
+                print(f"error: {ex}")
+                return 1
+            except Exception as ex:
+                print(f"error: cannot determine moint point for {path}: {ex}")
+                return 1
+            mounts.append(mount_path)
+
+        # Warn the user since this operation permanently destroys data
+        if args.prompt and sys.stdin.isatty():
+            mounts_list = "\n  ".join(mounts)
+            print(
+                f"""\
+Warning: this operation will permanently delete the following checkouts:
+  {mounts_list}
+
+Any uncommitted changes and shelves in this checkout will be lost forever."""
+            )
+            if not prompt_confirmation("Proceed?"):
+                print("Not confirmed")
+                return 2
+
+        # Unmount + destroy everything
+        for mount in mounts:
+            print(f"Removing {mount}...")
+            try:
+                config.unmount(mount, delete_config=True)
+            except EdenService.EdenError as ex:
+                print_stderr("error: {}", ex)
+                return 1
+
+        print(f"Success")
+        return 0
+
+
 @subcmd("unmount", "Unmount a specific checkout")
 class UnmountCmd(Subcmd):
 
@@ -527,7 +589,7 @@ class StartCmd(Subcmd):
         )
 
 
-def stop_aux_processes(client) -> None:
+def stop_aux_processes(client: eden.thrift.EdenClient) -> None:
     """Tear down processes that will hold onto file handles and prevent shutdown"""
 
     active_mount_points: Set[Optional[str]] = {
@@ -738,16 +800,16 @@ def create_parser() -> argparse.ArgumentParser:
     return parser
 
 
-def main() -> int:
-    parser = create_parser()
-    args = parser.parse_args()
-    if args.version:
-        return do_version(args)
-    if getattr(args, "func", None) is None:
-        parser.print_help()
-        return 0
-    return_code: int = args.func(args)
-    return return_code
+def prompt_confirmation(prompt: str) -> bool:
+    prompt_str = f"{prompt} [y/N] "
+    while True:
+        response = input(prompt_str)
+        value = response.lower()
+        if value in ("y", "yes"):
+            return True
+        if value in ("", "n", "no"):
+            return False
+        print('Please enter "yes" or "no"')
 
 
 def normalize_path_arg(path_arg: str, may_need_tilde_expansion: bool = False) -> str:
@@ -766,6 +828,18 @@ def normalize_path_arg(path_arg: str, may_need_tilde_expansion: bool = False) ->
     return path_arg
 
 
+def main() -> int:
+    parser = create_parser()
+    args = parser.parse_args()
+    if args.version:
+        return do_version(args)
+    if getattr(args, "func", None) is None:
+        parser.print_help()
+        return 0
+    return_code: int = args.func(args)
+    return return_code
+
+
 if __name__ == "__main__":
     retcode = main()
     sys.exit(retcode)

eden/cli/util.py

@@ -39,6 +39,15 @@ class ShutdownError(Exception):
     pass
 
 
+class NotAnEdenMountError(Exception):
+
+    def __init__(self, path: str) -> None:
+        self.path = path
+
+    def __str__(self) -> str:
+        return f"{self.path} does not appear to be inside an Eden checkout"
+
+
 class HealthStatus(object):
 
     def __init__(self, status: int, pid: Optional[int], detail: str) -> None:
@@ -423,3 +432,19 @@ def read_all(path: str) -> str:
     """One-liner to read the contents of a file and properly close the fd."""
     with open(path, "r") as f:
         return f.read()
+
+
+def get_eden_mount_name(path_arg: str) -> str:
+    """
+    Get the path to the Eden checkout containing the specified path
+    """
+    path = os.path.join(path_arg, ".eden", "root")
+    try:
+        return os.readlink(path)
+    except OSError as ex:
+        if ex.errno == errno.ENOTDIR:
+            path = os.path.join(os.path.dirname(path_arg), ".eden", "root")
+            return os.readlink(path)
+        elif ex.errno == errno.ENOENT:
+            raise NotAnEdenMountError(path_arg)
+        raise

eden/integration/basic_test.py

@@ -216,13 +216,17 @@ class BasicTest(testcase.EdenRepoTest):
             msg="attempting to run noexec.sh should fail with " "EACCES",
         )
 
+    def test_remove_invalid_paths(self) -> None:
+        self.eden.run_unchecked("remove", "/tmp")
+        self.eden.run_unchecked("remove", "/root")
+
     def test_unmount(self) -> None:
         entries = set(os.listdir(self.mount))
         self.assertEqual(self.expected_mount_entries, entries)
 
         self.assertTrue(self.eden.in_proc_mounts(self.mount))
 
-        self.eden.unmount(self.mount)
+        self.eden.remove(self.mount)
 
         self.assertFalse(self.eden.in_proc_mounts(self.mount))
         self.assertFalse(os.path.exists(self.mount))

eden/integration/clone_test.py

@@ -67,7 +67,7 @@ class CloneTest(testcase.EdenRepoTest):
                 empty_dir, active_mount_points, msg="mounted using the realpath"
             )
 
-        self.eden.run_cmd("unmount", "--destroy", symlinked_target)
+        self.eden.run_cmd("remove", "--yes", symlinked_target)
 
     def test_clone_to_existing_empty_directory(self) -> None:
         tmp = self._new_tmp_dir()

eden/integration/lib/edenclient.py

@@ -361,11 +361,11 @@ class EdenFS(object):
             params.append("--allow-empty-repo")
         self.run_cmd(*params)
 
-    def unmount(self, path: str) -> None:
+    def remove(self, path: str) -> None:
         """
-        Run "eden unmount --destroy <path>"
+        Run "eden remove <path>"
         """
-        self.run_cmd("unmount", "--destroy", path)
+        self.run_cmd("remove", "--yes", path)
 
     def in_proc_mounts(self, mount_path: str) -> bool:
         """Gets all eden mounts found in /proc/mounts, and returns

eden/integration/rc_test.py

@@ -27,9 +27,9 @@ class RCTest(testcase.EdenRepoTest):
         mounts = self.eden.list_cmd()
         self.assertEqual({self.mount: self.eden.CLIENT_ACTIVE}, mounts)
 
-        self.eden.unmount(self.mount)
+        self.eden.remove(self.mount)
         mounts = self.eden.list_cmd()
-        self.assertEqual({}, mounts, msg="There should be 0 mount paths after unmount")
+        self.assertEqual({}, mounts, msg="There should be 0 mount paths after remove")
 
         self.eden.clone(self.repo_name, self.mount)
         mounts = self.eden.list_cmd()
@@ -45,10 +45,10 @@ class RCTest(testcase.EdenRepoTest):
         mounts = self.eden.list_cmd()
         self.assertEqual({self.mount: self.eden.CLIENT_ACTIVE}, mounts)
 
-        self.eden.unmount(self.mount)
+        self.eden.remove(self.mount)
         self.assertFalse(os.path.isdir(test_client_dir))
 
-        # Check that _remove_path_from_directory_map in unmount is successful
+        # Check that _remove_path_from_directory_map in remove is successful
         mounts = self.eden.list_cmd()
         self.assertEqual({}, mounts, msg="There should be 0 paths in the directory map")
 

eden/integration/remount_test.py

@@ -85,7 +85,7 @@ class RemountTest(testcase.EdenRepoTest):
             self.eden.clone(self.repo_name, self.mount + "-" + str(i))
 
         # Unmount a client
-        self.eden.unmount(self.mount)
+        self.eden.remove(self.mount)
         self.assertFalse(os.path.exists(self.mount))
 
         self.eden.shutdown()
@@ -108,8 +108,8 @@ class RemountTest(testcase.EdenRepoTest):
         self.eden.start()
 
         # Unmount clients
-        self.eden.unmount(self.mount)
-        self.eden.unmount(self.mount + "-3")
+        self.eden.remove(self.mount)
+        self.eden.remove(self.mount + "-3")
 
         self.eden.shutdown()
         self.eden.start()