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✏️ Editing: glusterfs.py

"""
Manage a glusterfs pool
"""

import logging
import re
import sys
import xml.etree.ElementTree as ET

import salt.utils.cloud
import salt.utils.path
from salt.exceptions import CommandExecutionError, SaltInvocationError

log = logging.getLogger(__name__)

def __virtual__():
    """
    Only load this module if the gluster command exists
    """
    if salt.utils.path.which("gluster"):
        return True
    return (False, "glusterfs server is not installed")

def _get_version():
    # Set the default minor version to 6 for tests
    version = [3, 6]
    cmd = "gluster --version"
    result = __salt__["cmd.run"](cmd).splitlines()
    for line in result:
        m = re.match(r"glusterfs ((?:\d+\.)+\d+)", line)
        if m:
            version = m.group(1).split(".")
            version = [int(i) for i in version]
    return tuple(version)

def _gluster_ok(xml_data):
    """
    Extract boolean return value from Gluster's XML output.
    """
    return int(xml_data.find("opRet").text) == 0

def _gluster_output_cleanup(result):
    """
    Gluster versions prior to 6 have a bug that requires tricking
    isatty. This adds "gluster> " to the output. Strip it off and
    produce clean xml for ElementTree.
    """
    ret = ""
    for line in result.splitlines():
        if line.startswith("gluster>"):
            ret += line[9:].strip()
        elif line.startswith("Welcome to gluster prompt"):
            pass
        else:
            ret += line.strip()

return ret

def _gluster_xml(cmd):
    """
    Perform a gluster --xml command and log result.
    """
    # We will pass the command string as stdin to allow for much longer
    # command strings. This is especially useful for creating large volumes
    # where the list of bricks exceeds 128 characters.
    if _get_version() < (
        3,
        6,
    ):
        result = __salt__["cmd.run"](
            'script -q -c "gluster --xml --mode=script"', stdin=f"{cmd}\n\004"
        )
    else:
        result = __salt__["cmd.run"]("gluster --xml --mode=script", stdin=f"{cmd}\n")

try:
        root = ET.fromstring(_gluster_output_cleanup(result))
    except ET.ParseError:
        raise CommandExecutionError("\n".join(result.splitlines()[:-1]))

if _gluster_ok(root):
        output = root.find("output")
        if output is not None:
            log.info('Gluster call "%s" succeeded: %s', cmd, root.find("output").text)
        else:
            log.info('Gluster call "%s" succeeded', cmd)
    else:
        log.error("Failed gluster call: %s: %s", cmd, root.find("opErrstr").text)

return root

def _gluster(cmd):
    """
    Perform a gluster command and return a boolean status.
    """
    return _gluster_ok(_gluster_xml(cmd))

def _etree_to_dict(t):
    d = {}
    for child in t:
        d[child.tag] = _etree_to_dict(child)
    return d or t.text

def _iter(root, term):
    """
    Checks for python2.6 or python2.7
    """
    if sys.version_info < (2, 7):
        return root.getiterator(term)
    else:
        return root.iter(term)

def peer_status():
    """
    Return peer status information

The return value is a dictionary with peer UUIDs as keys and dicts of peer
    information as values. Hostnames are listed in one list. GlusterFS separates
    one of the hostnames but the only reason for this seems to be which hostname
    happens to be used first in peering.

CLI Example:

.. code-block:: bash

salt '*' glusterfs.peer_status

GLUSTER direct CLI example (to show what salt is sending to gluster):

$ gluster peer status

GLUSTER CLI 3.4.4 return example (so we know what we are parsing):

Number of Peers: 2

Hostname: ftp2
        Port: 24007
        Uuid: cbcb256b-e66e-4ec7-a718-21082d396c24
        State: Peer in Cluster (Connected)

Hostname: ftp3
        Uuid: 5ea10457-6cb2-427b-a770-7897509625e9
        State: Peer in Cluster (Connected)

"""
    root = _gluster_xml("peer status")
    if not _gluster_ok(root):
        return None

result = {}
    for peer in _iter(root, "peer"):
        uuid = peer.find("uuid").text
        result[uuid] = {"hostnames": []}
        for item in peer:
            if item.tag == "hostname":
                result[uuid]["hostnames"].append(item.text)
            elif item.tag == "hostnames":
                for hostname in item:
                    if hostname.text not in result[uuid]["hostnames"]:
                        result[uuid]["hostnames"].append(hostname.text)
            elif item.tag != "uuid":
                result[uuid][item.tag] = item.text
    return result

def peer(name):
    """
    Add another node into the peer list.

name
        The remote host to probe.

CLI Example:

.. code-block:: bash

salt 'one.gluster.*' glusterfs.peer two

GLUSTER direct CLI example (to show what salt is sending to gluster):

$ gluster peer probe ftp2

GLUSTER CLI 3.4.4 return example (so we know what we are parsing):
        #if the "peer" is the local host:
        peer probe: success: on localhost not needed

#if the peer was just added:
        peer probe: success

#if the peer was already part of the cluster:
        peer probe: success: host ftp2 port 24007 already in peer list

"""
    if salt.utils.cloud.check_name(name, "a-zA-Z0-9._-"):
        raise SaltInvocationError(f'Invalid characters in peer name "{name}"')

cmd = f"peer probe {name}"
    return _gluster(cmd)

def create_volume(
    name,
    bricks,
    stripe=False,
    replica=False,
    device_vg=False,
    transport="tcp",
    start=False,
    force=False,
    arbiter=False,
):
    """
    Create a glusterfs volume

name
        Name of the gluster volume

bricks
        Bricks to create volume from, in <peer>:<brick path> format. For \
        multiple bricks use list format: '["<peer1>:<brick1>", \
        "<peer2>:<brick2>"]'

stripe
        Stripe count, the number of bricks should be a multiple of the stripe \
        count for a distributed striped volume

replica
        Replica count, the number of bricks should be a multiple of the \
        replica count for a distributed replicated volume

arbiter
        If true, specifies volume should use arbiter brick(s). \
        Valid configuration limited to "replica 3 arbiter 1" per \
        Gluster documentation. Every third brick in the brick list \
        is used as an arbiter brick.

.. versionadded:: 2019.2.0

device_vg
        If true, specifies volume should use block backend instead of regular \
        posix backend. Block device backend volume does not support multiple \
        bricks

transport
        Transport protocol to use, can be 'tcp', 'rdma' or 'tcp,rdma'

start
        Start the volume after creation

force
        Force volume creation, this works even if creating in root FS

CLI Examples:

.. code-block:: bash

salt host1 glusterfs.create newvolume host1:/brick

salt gluster1 glusterfs.create vol2 '["gluster1:/export/vol2/brick", \
        "gluster2:/export/vol2/brick"]' replica=2 start=True
    """
    # If single brick given as a string, accept it
    if isinstance(bricks, str):
        bricks = [bricks]

# Error for block devices with multiple bricks
    if device_vg and len(bricks) > 1:
        raise SaltInvocationError(
            "Block device backend volume does not " + "support multiple bricks"
        )

# Validate bricks syntax
    for brick in bricks:
        try:
            peer_name, path = brick.split(":")
            if not path.startswith("/"):
                raise SaltInvocationError(f"Brick paths must start with / in {brick}")
        except ValueError:
            raise SaltInvocationError(f"Brick syntax is <peer>:<path> got {brick}")

# Validate arbiter config
    if arbiter and replica != 3:
        raise SaltInvocationError(
            "Arbiter configuration only valid " + "in replica 3 volume"
        )

# Format creation call
    cmd = f"volume create {name} "
    if stripe:
        cmd += f"stripe {stripe} "
    if replica:
        cmd += f"replica {replica} "
    if arbiter:
        cmd += "arbiter 1 "
    if device_vg:
        cmd += "device vg "
    if transport != "tcp":
        cmd += f"transport {transport} "
    cmd += " ".join(bricks)
    if force:
        cmd += " force"

if not _gluster(cmd):
        return False

if start:
        return start_volume(name)
    return True

def list_volumes():
    """
    List configured volumes

CLI Example:

.. code-block:: bash

salt '*' glusterfs.list_volumes
    """

root = _gluster_xml("volume list")
    if not _gluster_ok(root):
        return None
    results = [x.text for x in _iter(root, "volume")]
    return results

def status(name):
    """
    Check the status of a gluster volume.

name
        Volume name

CLI Example:

.. code-block:: bash

salt '*' glusterfs.status myvolume
    """
    # Get volume status
    root = _gluster_xml(f"volume status {name}")
    if not _gluster_ok(root):
        # Most probably non-existing volume, the error output is logged
        # This return value is easy to test and intuitive
        return None

ret = {"bricks": {}, "nfs": {}, "healers": {}}

def etree_legacy_wrap(t):
        ret = _etree_to_dict(t)
        ret["online"] = ret["status"] == "1"
        ret["host"] = ret["hostname"]
        return ret

# Build a hash to map hostname to peerid
    hostref = {}
    for node in _iter(root, "node"):
        peerid = node.find("peerid").text
        hostname = node.find("hostname").text
        if hostname not in ("NFS Server", "Self-heal Daemon"):
            hostref[peerid] = hostname

for node in _iter(root, "node"):
        hostname = node.find("hostname").text
        if hostname not in ("NFS Server", "Self-heal Daemon"):
            path = node.find("path").text
            ret["bricks"][f"{hostname}:{path}"] = etree_legacy_wrap(node)
        elif hostname == "NFS Server":
            peerid = node.find("peerid").text
            true_hostname = hostref[peerid]
            ret["nfs"][true_hostname] = etree_legacy_wrap(node)
        else:
            peerid = node.find("peerid").text
            true_hostname = hostref[peerid]
            ret["healers"][true_hostname] = etree_legacy_wrap(node)

return ret

def info(name=None):
    """
    .. versionadded:: 2015.8.4

Return gluster volume info.

name
        Optional name to retrieve only information of one volume

CLI Example:

.. code-block:: bash

salt '*' glusterfs.info
    """
    cmd = "volume info"
    if name is not None:
        cmd += " " + name

root = _gluster_xml(cmd)
    if not _gluster_ok(root):
        return None

ret = {}
    for volume in _iter(root, "volume"):
        name = volume.find("name").text
        ret[name] = _etree_to_dict(volume)

bricks = {}
        for i, brick in enumerate(_iter(volume, "brick"), start=1):
            brickkey = f"brick{i}"
            bricks[brickkey] = {"path": brick.text}
            for child in brick:
                if not child.tag == "name":
                    bricks[brickkey].update({child.tag: child.text})
            for k, v in brick.items():
                bricks[brickkey][k] = v
        ret[name]["bricks"] = bricks

options = {}
        for option in _iter(volume, "option"):
            options[option.find("name").text] = option.find("value").text
        ret[name]["options"] = options

return ret

def start_volume(name, force=False):
    """
    Start a gluster volume

name
        Volume name

force
        Force the volume start even if the volume is started
        .. versionadded:: 2015.8.4

CLI Example:

.. code-block:: bash

salt '*' glusterfs.start mycluster
    """
    cmd = f"volume start {name}"
    if force:
        cmd = f"{cmd} force"

volinfo = info(name)
    if name not in volinfo:
        log.error("Cannot start non-existing volume %s", name)
        return False

if not force and volinfo[name]["status"] == "1":
        log.info("Volume %s already started", name)
        return True

return _gluster(cmd)

def stop_volume(name, force=False):
    """
    Stop a gluster volume

name
        Volume name

force
        Force stop the volume

.. versionadded:: 2015.8.4

CLI Example:

.. code-block:: bash

salt '*' glusterfs.stop_volume mycluster
    """
    volinfo = info()
    if name not in volinfo:
        log.error("Cannot stop non-existing volume %s", name)
        return False
    if int(volinfo[name]["status"]) != 1:
        log.warning("Attempt to stop already stopped volume %s", name)
        return True

cmd = f"volume stop {name}"
    if force:
        cmd += " force"

return _gluster(cmd)

def delete_volume(target, stop=True):
    """
    Deletes a gluster volume

target
        Volume to delete

stop : True
        If ``True``, stop volume before delete

CLI Example:

.. code-block:: bash

salt '*' glusterfs.delete_volume <volume>
    """
    volinfo = info()
    if target not in volinfo:
        log.error("Cannot delete non-existing volume %s", target)
        return False

# Stop volume if requested to and it is running
    running = volinfo[target]["status"] == "1"

if not stop and running:
        # Fail if volume is running if stop is not requested
        log.error("Volume %s must be stopped before deletion", target)
        return False

if running:
        if not stop_volume(target, force=True):
            return False

cmd = f"volume delete {target}"
    return _gluster(cmd)

def add_volume_bricks(name, bricks):
    """
    Add brick(s) to an existing volume

name
        Volume name

bricks
        List of bricks to add to the volume

CLI Example:

.. code-block:: bash

salt '*' glusterfs.add_volume_bricks <volume> <bricks>
    """

volinfo = info()
    if name not in volinfo:
        log.error("Volume %s does not exist, cannot add bricks", name)
        return False

new_bricks = []

cmd = f"volume add-brick {name}"

if isinstance(bricks, str):
        bricks = [bricks]

volume_bricks = [x["path"] for x in volinfo[name]["bricks"].values()]

for brick in bricks:
        if brick in volume_bricks:
            log.debug(
                "Brick %s already in volume %s...excluding from command", brick, name
            )
        else:
            new_bricks.append(brick)

if new_bricks:
        for brick in new_bricks:
            cmd += f" {brick}"
        return _gluster(cmd)
    return True

def enable_quota_volume(name):
    """
    Enable quota on a glusterfs volume.

name
        Name of the gluster volume

CLI Example:

.. code-block:: bash

salt '*' glusterfs.enable_quota_volume <volume>
    """

cmd = f"volume quota {name} enable"
    if not _gluster(cmd):
        return False
    return True

def disable_quota_volume(name):
    """
    Disable quota on a glusterfs volume.

name
        Name of the gluster volume

CLI Example:

.. code-block:: bash

salt '*' glusterfs.disable_quota_volume <volume>
    """

cmd = f"volume quota {name} disable"
    if not _gluster(cmd):
        return False
    return True

def set_quota_volume(name, path, size, enable_quota=False):
    """
    Set quota to glusterfs volume.

name
        Name of the gluster volume

path
        Folder path for restriction in volume ("/")

size
        Hard-limit size of the volume (MB/GB)

enable_quota
        Enable quota before set up restriction

CLI Example:

.. code-block:: bash

salt '*' glusterfs.set_quota_volume <volume> <path> <size> enable_quota=True
    """
    cmd = f"volume quota {name}"
    if path:
        cmd += f" limit-usage {path}"
    if size:
        cmd += f" {size}"

if enable_quota:
        if not enable_quota_volume(name):
            pass
    if not _gluster(cmd):
        return False
    return True

def unset_quota_volume(name, path):
    """
    Unset quota on glusterfs volume

name
        Name of the gluster volume

path
        Folder path for restriction in volume

CLI Example:

.. code-block:: bash

salt '*' glusterfs.unset_quota_volume <volume> <path>
    """
    cmd = f"volume quota {name}"
    if path:
        cmd += f" remove {path}"

if not _gluster(cmd):
        return False
    return True

def list_quota_volume(name):
    """
    List quotas of glusterfs volume

name
        Name of the gluster volume

CLI Example:

.. code-block:: bash

salt '*' glusterfs.list_quota_volume <volume>
    """
    cmd = f"volume quota {name}"
    cmd += " list"

root = _gluster_xml(cmd)
    if not _gluster_ok(root):
        return None

ret = {}
    for limit in _iter(root, "limit"):
        path = limit.find("path").text
        ret[path] = _etree_to_dict(limit)

return ret

def get_op_version(name):
    """
    .. versionadded:: 2019.2.0

Returns the glusterfs volume op-version

name
        Name of the glusterfs volume

CLI Example:

.. code-block:: bash

salt '*' glusterfs.get_op_version <volume>
    """

cmd = f"volume get {name} cluster.op-version"
    root = _gluster_xml(cmd)

if not _gluster_ok(root):
        return False, root.find("opErrstr").text

result = {}
    for op_version in _iter(root, "volGetopts"):
        for item in op_version:
            if item.tag == "Value":
                result = item.text
            elif item.tag == "Opt":
                for child in item:
                    if child.tag == "Value":
                        result = child.text

return result

def get_max_op_version():
    """
    .. versionadded:: 2019.2.0

Returns the glusterfs volume's max op-version value
    Requires Glusterfs version > 3.9

CLI Example:

.. code-block:: bash

salt '*' glusterfs.get_max_op_version
    """
    if _get_version() < (
        3,
        10,
    ):
        return (
            False,
            "Glusterfs version must be 3.10+.  Your version is {}.".format(
                str(".".join(str(i) for i in _get_version()))
            ),
        )

cmd = "volume get all cluster.max-op-version"
    root = _gluster_xml(cmd)

if not _gluster_ok(root):
        return False, root.find("opErrstr").text

result = {}
    for max_op_version in _iter(root, "volGetopts"):
        for item in max_op_version:
            if item.tag == "Value":
                result = item.text
            elif item.tag == "Opt":
                for child in item:
                    if child.tag == "Value":
                        result = child.text

return result

def set_op_version(version):
    """
    .. versionadded:: 2019.2.0

Set the glusterfs volume op-version

version
        Version to set the glusterfs volume op-version

CLI Example:

.. code-block:: bash

salt '*' glusterfs.set_op_version <volume>
    """

cmd = f"volume set all cluster.op-version {version}"
    root = _gluster_xml(cmd)

if not _gluster_ok(root):
        return False, root.find("opErrstr").text

return root.find("output").text

def get_version():
    """
    .. versionadded:: 2019.2.0

Returns the version of glusterfs.

CLI Example:

.. code-block:: bash

salt '*' glusterfs.get_version
    """

return ".".join(_get_version())

MR SKB