grass.app: Move lock to mapset subcommand (#6437)

The lock and unlock subcommands are operating on a mapset and are low-level (they specifically just lock and unlock and don't do anything with any session). So, this is moving them under a new top-level subcommand mapset (from #6462).

With the lock subcommands being accessible outside of GRASS through CLI without a Python API or a GRASS tools (with or without #6442), other applications which can call subprocesses (such as QGIS) can use GRASS locking when accessing GRASS mapsets.

This is using the new structure in the cli.py file with parser definitions having their own functions (minimizing name conflicts between parses and keeping the main function short). Additionally, the interface and execution code are placed together because they would be changed at the same time.

Tests now test locking the the default mapset and a separate mapset in a smoke test fashion (more in-depth tests exist in the Python API).

Example: grass mapset lock /tmp/project_1/work_2

Author: wenzeslaus

python/grass/app/cli.py

@@ -100,6 +100,37 @@ def add_mapset_subparser(subparsers):
     subparser.add_argument("path", help="path to the new mapset")
     subparser.set_defaults(func=subcommand_mapset_create)
 
+    subparser = mapset_subparsers.add_parser("lock", help="lock a mapset")
+    subparser.add_argument("mapset_path", type=str)
+    subparser.add_argument(
+        "--process-id",
+        metavar="PID",
+        type=int,
+        default=1,
+        help=_(
+            "process ID of the process locking the mapset (a mapset can be "
+            "automatically unlocked if there is no process with this PID)"
+        ),
+    )
+    subparser.add_argument(
+        "--timeout",
+        metavar="TIMEOUT",
+        type=float,
+        default=30,
+        help=_("mapset locking timeout in seconds"),
+    )
+    subparser.add_argument(
+        "-f",
+        "--force-remove-lock",
+        action="store_true",
+        help=_("remove lock if present"),
+    )
+    subparser.set_defaults(func=subcommand_lock_mapset)
+
+    subparser = mapset_subparsers.add_parser("unlock", help="unlock a mapset")
+    subparser.add_argument("mapset_path", type=str)
+    subparser.set_defaults(func=subcommand_unlock_mapset)
+
 
 def subcommand_mapset_create(args) -> int:
     try:
@@ -110,7 +141,7 @@ def subcommand_mapset_create(args) -> int:
     return 0
 
 
-def subcommand_lock_mapset(args):
+def subcommand_lock_mapset(args) -> int:
     gs.setup.setup_runtime_env()
     try:
         lock_mapset(
@@ -122,10 +153,17 @@ def subcommand_lock_mapset(args):
         )
     except MapsetLockingException as e:
         print(str(e), file=sys.stderr)
+        return 1
+    return 0
 
 
-def subcommand_unlock_mapset(args):
-    unlock_mapset(args.mapset_path)
+def subcommand_unlock_mapset(args) -> int:
+    try:
+        unlock_mapset(args.mapset_path)
+    except OSError as error:
+        print(str(error), file=sys.stderr)
+        return 1
+    return 0
 
 
 def call_g_manual(**kwargs):
@@ -222,37 +260,6 @@ def main(args=None, program=None):
     add_project_subparser(subparsers)
     add_mapset_subparser(subparsers)
 
-    subparser = subparsers.add_parser("lock", help="lock a mapset")
-    subparser.add_argument("mapset_path", type=str)
-    subparser.add_argument(
-        "--process-id",
-        metavar="PID",
-        type=int,
-        default=1,
-        help=_(
-            "process ID of the process locking the mapset (a mapset can be "
-            "automatically unlocked if there is no process with this PID)"
-        ),
-    )
-    subparser.add_argument(
-        "--timeout",
-        metavar="TIMEOUT",
-        type=float,
-        default=30,
-        help=_("mapset locking timeout in seconds"),
-    )
-    subparser.add_argument(
-        "-f",
-        "--force-remove-lock",
-        action="store_true",
-        help=_("remove lock if present"),
-    )
-    subparser.set_defaults(func=subcommand_lock_mapset)
-
-    subparser = subparsers.add_parser("unlock", help="unlock a mapset")
-    subparser.add_argument("mapset_path", type=str)
-    subparser.set_defaults(func=subcommand_unlock_mapset)
-
     subparser = subparsers.add_parser(
         "help", help="show HTML documentation for a tool or topic"
     )

python/grass/app/tests/grass_app_cli_test.py

@@ -129,6 +129,23 @@ def test_subcommand_run_with_crs_as_pack_subprocess(pack_raster_file4x5_rows, ca
     assert json.loads(result.stdout)["srid"] == "EPSG:3358"
 
 
+def test_create_lock_unlock(tmp_path):
+    """Check that we can create, lock, unlock (smoke test)"""
+    project = tmp_path / "test_1"
+    assert main(["project", "create", str(project)]) == 0
+    assert main(["mapset", "lock", str(project / "PERMANENT")]) == 0
+    assert main(["mapset", "unlock", str(project / "PERMANENT")]) == 0
+
+
+def test_create_mapset_lock_unlock(tmp_path):
+    """Check that we can create, lock, unlock (smoke test)"""
+    project = tmp_path / "test_1"
+    assert main(["project", "create", str(project)]) == 0
+    assert main(["mapset", "create", str(project / "data_1")]) == 0
+    assert main(["mapset", "lock", str(project / "data_1")]) == 0
+    assert main(["mapset", "unlock", str(project / "data_1")]) == 0
+
+
 def test_create_mapset(tmp_path):
     """Check that we can create mapset and we can set its computational region"""
     project = tmp_path / "test_1"