Add comprehensive test for virsh managedsave-edit

This commit introduces a new test for `virsh managedsave-edit`,
verifying its ability to modify a VM's saved XML configuration,
specifically the disk path, and successfully restore the VM. It includes
scenarios for different VM states and validates error handling for
invalid options and readonly mode.

Signed-off-by: Yalan Zhang <yalzhang@redhat.com>

Author: yalzhang

libvirt/tests/cfg/save_and_restore/managedsave_edit.cfg

@@ -0,0 +1,25 @@
+- save_and_restore.managedsave_edit:
+    type = managedsave_edit
+    start_vm = "yes"
+    status_error = "no"
+    variants:
+        - opt_none:
+            virsh_opt = ''
+            pre_state = 'running'
+        - opt_running:
+            virsh_opt = '--running'
+            pre_state = 'paused'
+        - opt_paused:
+            virsh_opt = '--paused'
+            pre_state = 'running'
+        - opt_exclusive:
+            virsh_opt = '--running --paused'
+            pre_state = 'running'
+            status_error = 'yes'
+    variants:
+        - normal:
+            readonly = 'no'
+        - readonly:
+            only opt_none
+            readonly = 'yes'
+            status_error = 'yes'

libvirt/tests/src/save_and_restore/managedsave_edit.py

@@ -0,0 +1,120 @@
+import logging
+import os
+import re
+import shutil
+
+from virttest import virsh
+from virttest.utils_test import libvirt
+
+LOG = logging.getLogger("avocado.test." + __name__)
+
+
+def vm_state_check(test, vm_name, new_disk_path, virsh_opt):
+    """
+    Check domain xml and state after restore from saved image.
+    """
+    cmd_re = virsh.dumpxml(vm_name, debug=True)
+    if cmd_re.exit_status:
+        test.fail(f"Failed to dump xml of domain '{vm_name}'")
+
+    # The xml should contain the match_string
+    xml = cmd_re.stdout.strip()
+    xml_pattern = f"<source file='{new_disk_path}'"
+    LOG.info(f"Checking for disk path '{new_disk_path}' in domain XML.")
+
+    if not re.search(xml_pattern, xml):
+        test.fail(
+            f"After domain restore the xml is not expected, could not find source file='{new_disk_path}'"
+        )
+    else:
+        LOG.info(f"Found source file='{new_disk_path}' in the domain xml successfully!")
+
+    dom_state = virsh.domstate(vm_name, debug=True).stdout.strip()
+    LOG.info(f"VM state after restore is '{dom_state}'")
+    if virsh_opt == "--running" and dom_state != "running":
+        test.fail(
+            "The domain state is not as expected with option '--running'. Got 'paused', expected 'running'"
+        )
+    elif virsh_opt == "--paused" and dom_state != "paused":
+        test.fail(
+            "The domain state is not as expected with option '--paused'. Got 'running', expected 'paused'"
+        )
+
+
+def run(test, params, env):
+    """
+    Test command: virsh managedsave-edit <vm_name> [option]
+    1) Prepare test environment, ensure VM is in requested state: running or paused
+    2) Do managedsave for the VM
+    3) Execute virsh managedsave-edit to edit xml
+    4) Start VM
+    5) Check the new xml of the VM and its state
+    """
+    pre_state = params.get("pre_state")
+    readonly = "yes" == params.get("readonly", "no")
+    status_error = "yes" == params.get("status_error", "no")
+    virsh_opt = params.get("virsh_opt")
+
+    vm_name = params.get("main_vm")
+    vm = env.get_vm(vm_name)
+    new_path = None
+    try:
+        LOG.info("Preparing the VM state...")
+        if not vm.is_alive():
+            vm.start()
+        if pre_state == "paused":
+            virsh.suspend(vm_name, debug=True)
+        vm_state = virsh.domstate(vm_name).stdout_text.strip()
+        LOG.info(f"The VM state is '{vm_state}' before save")
+
+        LOG.info("TEST STEP 1: Perform 'virsh managedsave' to save the vm...")
+        cmd_result = virsh.managedsave(vm_name, debug=True)
+        libvirt.check_result(cmd_result)
+
+        LOG.info("TEST STEP 2: Run managedsave-edit to update the disk path:")
+        disk_path = vm.get_first_disk_devices()["source"]
+        new_path = f"{disk_path}.test"
+
+        # Ensure the new path does not already exist
+        if os.path.exists(new_path):
+            LOG.warning(f"The path '{new_path}' already exists. Removing it...")
+            os.remove(new_path)
+
+        shutil.copy(disk_path, new_path)
+        LOG.info(f"The original disk path is '{disk_path}'")
+        LOG.info(f"The new disk path will be: '{new_path}'")
+
+        replace_string = r":%s /" + disk_path.replace("/", "\/")
+        replace_string += "/" + new_path.replace("/", "\/")
+        stat = libvirt.exec_virsh_edit(
+            vm_name,
+            [replace_string],
+            managedsave_edit=True,
+            readonly=readonly,
+            virsh_opt=virsh_opt,
+        )
+        if not stat:
+            if status_error:
+                LOG.info("Failed to edit the xml, this was expected!")
+            else:
+                test.fail("managedsave-edit failed!")
+        else:
+            if status_error:
+                test.fail("managedsave-edit succeeded when it should have failed!")
+
+        if not status_error:
+            LOG.info("TEST STEP 3: Start VM for positive scenarios:")
+            cmd_result = virsh.start(vm_name, debug=True)
+            libvirt.check_result(cmd_result)
+            LOG.info(
+                "TEST STEP 4: Verify VM status and the XML content for positive scenarios:"
+            )
+            vm_state_check(test, vm_name, new_path, virsh_opt)
+    except Exception as e:
+        test.error(f"Unexpected error happened during the test execution: {e}")
+    finally:
+        # Cleanup
+        if new_path and os.path.exists(new_path):
+            LOG.info(f"Remove the file {new_path}")
+            os.remove(new_path)
+        virsh.managedsave_remove(vm_name, debug=True)