Add utils for domain backup function

Libvirt's incremental backup related supporting methods added in this file.

Signed-off-by: Yi Sun <[email protected]>

virttest/utils_backup.py

@@ -0,0 +1,266 @@
+import logging
+import os
+import json
+import filecmp
+
+from avocado.utils import process
+from avocado.core import exceptions
+
+from virttest import utils_misc
+from virttest.libvirt_xml.backup_xml import BackupXML
+from virttest.libvirt_xml.checkpoint_xml import CheckpointXML
+
+
+class BackupError(Exception):
+
+    """
+    Class of backup exception
+    """
+
+    def __init__(self, *args):
+        Exception.__init__(self, *args)
+
+
+class BackupBeginError(BackupError):
+
+    """
+    Class of backup begin exception
+    """
+
+    def __init__(self, error_info):
+        BackupError.__init__(self, error_info)
+        self.error_info = error_info
+
+    def __str__(self):
+        return "Backup failed: %s" % self.error_info
+
+
+def create_checkpoint_xml(cp_params, disk_param_list=None):
+    """
+    Create a checkpoint xml
+
+    :param cp_params: Params of checkpoint
+    :param disk_param_list: A list of disk params used in checkpoint xml
+    :return: The checkponit xml
+    """
+    cp_xml = CheckpointXML()
+    cp_name = cp_params.get("checkpoint_name")
+    cp_desc = cp_params.get("checkpoint_desc")
+    if not cp_name:
+        raise exceptions.TestError("Checkpoint name must be provided")
+    cp_xml.name = cp_name
+    if cp_desc:
+        cp_xml.description = cp_desc
+    if disk_param_list:
+        if not isinstance(disk_param_list, list):
+            raise exceptions.TestError("checkpoint disk tags should be defined "
+                                       "by a list.")
+        cp_xml.disks = disk_param_list
+    cp_xml.xmltreefile.write()
+
+    utils_misc.wait_for(lambda: os.path.exists(cp_xml.xml), 5)
+    return cp_xml
+
+
+def create_backup_xml(backup_params, disk_xml_list=None):
+    """
+    Create a backup xml
+
+    :param backup_params: Params of backup
+    :param disk_xml_list: A list of disk params used in backup xml
+    :return: The backup xml
+    """
+    backup_xml = BackupXML()
+    backup_mode = backup_params.get("backup_mode")
+    backup_incremental = backup_params.get("backup_incremental")
+    backup_server = backup_params.get("backup_server")
+    if backup_mode:
+        backup_xml.mode = backup_mode
+    if backup_incremental:
+        backup_xml.incremental = backup_incremental
+    if backup_server:
+        if not isinstance(backup_server, dict):
+            raise exceptions.TestError("Backup server tag should be defined by a dict.")
+        backup_xml.server = backup_server
+    backup_xml.set_disks(disk_xml_list)
+    backup_xml.xmltreefile.write()
+
+    utils_misc.wait_for(lambda: os.path.exists(backup_xml.xml), 5)
+    return backup_xml
+
+
+def create_backup_disk_xml(backup_disk_params):
+    """
+    Create a disk xml which is a subelement of a backup xml
+
+    :param backup_disk_params: Params of disk xml
+    :return: The disk xml
+    """
+    backup_disk_xml = BackupXML.DiskXML()
+    disk_name = backup_disk_params.get("disk_name")
+    disk_type = backup_disk_params.get("disk_type")
+    enable_backup = backup_disk_params.get("enable_backup")
+    exportname = backup_disk_params.get("exportname")
+    exportbitmap = backup_disk_params.get("exportbitmap")
+    backup_target = backup_disk_params.get("backup_target")  # dict
+    backup_driver = backup_disk_params.get("backup_driver")  # dict
+    backup_scratch = backup_disk_params.get("backup_scratch")  # dict
+    if not disk_name:
+        raise exceptions.TestError("Disk name must be provided for backup disk xml.")
+    backup_disk_xml.name = disk_name
+    if disk_type:
+        backup_disk_xml.type = disk_type
+    if enable_backup:
+        backup_disk_xml.backup = enable_backup
+    if exportname:
+        backup_disk_xml.exportname = exportname
+    if exportbitmap:
+        backup_disk_xml.exportbitmap = exportbitmap
+    if backup_target:
+        if not isinstance(backup_target, dict):
+            raise exceptions.TestError("disk target tag should be defined by a dict.")
+        backup_disk_xml.target = backup_target
+    if backup_driver:
+        if not isinstance(backup_driver, dict):
+            raise exceptions.TestError("disk driver tag should be defined by a dict.")
+        backup_disk_xml.driver = backup_driver
+    if backup_scratch:
+        if not isinstance(backup_scratch, dict):
+            raise exceptions.TestError("disk scratch tag should be defined by a dict.")
+        backup_disk_xml.scratch = backup_scratch
+    backup_disk_xml.xmltreefile.write()
+
+    utils_misc.wait_for(lambda: os.path.exists(backup_disk_xml.xml), 5)
+    return backup_disk_xml
+
+
+def pull_incremental_backup_to_file(nbd_params, target_path,
+                                    bitmap_name, file_size):
+    """
+    Dump pull-mode incremental backup data to a file
+
+    :param nbd_params: The params of nbd service which provide the backup data
+    :param target_path: The path of the file to dump the data
+    :param bitmap_name: The dirty bitmap used for the backup
+    :param file_size: The size of the target file to be preapred
+    """
+    nbd_protocol = nbd_params.get("nbd_protocol", "tcp")
+    cmd = "qemu-img create -f qcow2 %s %s" % (target_path, file_size)
+    logging.debug(process.run(cmd, shell=True).stdout_text)
+    map_from = "--image-opts driver=nbd,export=%s,server.type=%s"
+    map_from += ",%s"
+    map_from += ",x-dirty-bitmap=qemu:dirty-bitmap:%s"
+    nbd_export = nbd_params.get("nbd_export", "vdb")
+    if nbd_protocol == "tcp":
+        nbd_host = nbd_params.get("nbd_host", "127.0.0.1")
+        nbd_tcp_port = nbd_params.get("nbd_tcp_port", "10809")
+        nbd_type = "inet"
+        nbd_server = "server.host=%s,server.port=%s" % (nbd_host, nbd_tcp_port)
+        nbd_image_path = "nbd://%s:%s/%s" % (nbd_host, nbd_tcp_port, nbd_export)
+    elif nbd_protocol == "unix":
+        nbd_type = "unix"
+        nbd_socket = nbd_params.get("nbd_socket", "/tmp/pull_backup.socket")
+        nbd_server = "server.path=%s" % nbd_socket
+        nbd_image_path = "nbd+unix:///%s?socket=%s" % (nbd_export, nbd_socket)
+    map_from %= (nbd_export, nbd_type, nbd_server, bitmap_name)
+    # Rebase backup file to nbd image
+    rebase_cmd = "qemu-img rebase -u -f qcow2 -F raw -b %s %s"
+    rebase_cmd %= (nbd_image_path, target_path)
+    process.run(rebase_cmd, shell=True)
+    # Remove backing chain of the backup file
+    qemu_map_cmd = "qemu-img map --output=json %s -U" % map_from
+    result = process.run(qemu_map_cmd, shell=True).stdout_text
+    json_data = json.loads(result)
+    for entry in json_data:
+        if not entry["data"]:
+            qemu_io_cmd = "qemu-io -C -c \"r %s %s\" -f qcow2 %s"
+            qemu_io_cmd %= (entry["start"], entry["length"], target_path)
+            process.run(qemu_io_cmd, shell=True)
+    # remove the backing file info for the target image
+    rebase_cmd = "qemu-img rebase -u -f qcow2 -b '' %s" % target_path
+    process.run(rebase_cmd, shell=True)
+
+
+def pull_full_backup_to_file(nbd_export, target_path):
+    """
+    Dump pull-mode full backup data to a file
+
+    :param nbd_export: The nbd export info of the backup job
+    :param target_path: The path of the file to dump the data
+    """
+    cmd = "qemu-img convert -f raw %s -O qcow2 %s" % (nbd_export,
+                                                      target_path)
+    logging.debug("Execute command %s: %s", cmd,
+                  process.run(cmd, shell=True).stdout_text)
+
+
+def get_img_data_size(img_path, driver='qcow2'):
+    """
+    Get the actual data size of a image
+
+    :param img_path: The path to the image
+    :return: The actual data size of the image in 'MB'.
+    """
+    cmd = "qemu-img map -f %s %s --output=json -U" % (driver, img_path)
+    result = process.run(cmd, shell=True).stdout_text
+    json_data = json.loads(result)
+    summary = 0
+    for entry in json_data:
+        if entry["data"]:
+            summary += entry["length"]
+    return summary/1024/1024
+
+
+def get_img_data_map(img_path, driver='qcow2'):
+    """
+    Get the data map of a image
+
+    :prama img_path: The path to the image
+    :return: The data map of the image
+    """
+    cmd = "qemu-img map -f %s %s --output=json -U" % (driver, img_path)
+    result = process.run(cmd, shell=True).stdout_text
+    json_data = json.loads(result)
+    data_map = []
+    for entry in json_data:
+        if entry["data"]:
+            data_map.append(entry)
+    return data_map
+
+
+def dump_data_to_file(data_map, source_file_path, target_file_path, driver='qcow2'):
+    """
+    Dump real data from the source file to a target file according to data map
+
+    :param data_map: The data map used to indicate which part of the image
+    containing real data
+    :param source_file_path: The path to the source file
+    :param target_file_path: The path to the target file
+    :param driver: The image format of the source file
+    """
+    with open(target_file_path, 'w'):
+        cmd = "qemu-io -f %s -c \"read -vC %s %s\" %s -r -U  | sed '$d'"
+        for entry in data_map:
+            cmd %= (driver, entry["start"], entry["length"], source_file_path)
+            cmd += ">> %s" % target_file_path
+            process.run(cmd, shell=True)
+
+
+def cmp_backup_data(original_file, backup_file,
+                    original_file_driver='qcow2', backup_file_driver='qcow2'):
+    """
+    Compare the backuped data and the original data
+
+    :param original_file: The file containing the original data
+    :param backup_file: The file containing the backuped data
+    :param original_file_driver: Original image format
+    :param backup_file_driver: Backup image format
+    :return: Trun if data is correct, false if not
+    """
+    original_file_dump = original_file + ".dump"
+    backup_file_dump = backup_file + ".dump"
+    data_map = get_img_data_map(backup_file, backup_file_driver)
+    dump_data_to_file(data_map, original_file, original_file_dump, original_file_driver)
+    dump_data_to_file(data_map, backup_file, backup_file_dump, backup_file_driver)
+    if filecmp.cmp(original_file_dump, backup_file_dump):
+        return True