Synnefo » snf-image-creator

# -*- coding: utf-8 -*-

#

# Copyright 2012 GRNET S.A. All rights reserved.

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# without modification, are permitted provided that the following

# conditions are met:

#

#   1. Redistributions of source code must retain the above

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#      disclaimer.

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#   2. Redistributions in binary form must reproduce the above

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# LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN

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"""This module implements the "expert" mode of the dialog-based version of

snf-image-creator.

"""

import os

import textwrap

import StringIO

import json

from image_creator import __version__ as version

from image_creator.util import MD5, FatalError

from image_creator.output.dialog import GaugeOutput, InfoBoxOutput

from image_creator.kamaki_wrapper import Kamaki, ClientError

from image_creator.help import get_help_file

from image_creator.dialog_util import SMALL_WIDTH, WIDTH, \

    update_background_title, confirm_reset, confirm_exit, Reset, \

    extract_image, extract_metadata_string, add_cloud, edit_cloud

CONFIGURATION_TASKS = [

    ("Partition table manipulation", ["FixPartitionTable"],

        ["linux", "windows"]),

    ("File system resize",

        ["FilesystemResizeUnmounted", "FilesystemResizeMounted"],

        ["linux", "windows"]),

    ("Swap partition configuration", ["AddSwap"], ["linux"]),

    ("SSH keys removal", ["DeleteSSHKeys"], ["linux"]),

    ("Temporal RDP disabling", ["DisableRemoteDesktopConnections"],

        ["windows"]),

    ("SELinux relabeling at next boot", ["SELinuxAutorelabel"], ["linux"]),

    ("Hostname/Computer Name assignment", ["AssignHostname"],

        ["windows", "linux"]),

    ("Password change", ["ChangePassword"], ["windows", "linux"]),

    ("File injection", ["EnforcePersonality"], ["windows", "linux"])

]

class MetadataMonitor(object):

    """Monitors image metadata chages"""

    def __init__(self, session, meta):

        self.session = session

        self.meta = meta

    def __enter__(self):

        self.old = {}

        for (k, v) in self.meta.items():

            self.old[k] = v

    def __exit__(self, type, value, traceback):

        d = self.session['dialog']

        altered = {}

        added = {}

        for (k, v) in self.meta.items():

            if k not in self.old:

                added[k] = v

            elif self.old[k] != v:

                altered[k] = v

        if not (len(added) or len(altered)):

            return

        msg = "The last action has changed some image properties:\n\n"

        if len(added):

            msg += "New image properties:\n"

            for (k, v) in added.items():

                msg += '    %s: "%s"\n' % (k, v)

            msg += "\n"

        if len(altered):

            msg += "Updated image properties:\n"

            for (k, v) in altered.items():

                msg += '    %s: "%s" -> "%s"\n' % (k, self.old[k], v)

            msg += "\n"

        self.session['metadata'].update(added)

        self.session['metadata'].update(altered)

        d.msgbox(msg, title="Image Property Changes", width=SMALL_WIDTH)

def upload_image(session):

    """Upload the image to the storage service"""

    d = session["dialog"]

    image = session['image']

    meta = session['metadata']

    size = image.size

    if "account" not in session:

        d.msgbox("You need to select a valid cloud before you can upload "

                 "images to it", width=SMALL_WIDTH)

        return False

    while 1:

        if 'upload' in session:

            init = session['upload']

        elif 'OS' in meta:

            init = "%s.diskdump" % meta['OS']

        else:

            init = ""

        (code, answer) = d.inputbox("Please provide a filename:", init=init,

                                    width=WIDTH)

        if code in (d.DIALOG_CANCEL, d.DIALOG_ESC):

            return False

        filename = answer.strip()

        if len(filename) == 0:

            d.msgbox("Filename cannot be empty", width=SMALL_WIDTH)

            continue

        kamaki = Kamaki(session['account'], None)

        overwrite = []

        for f in (filename, "%s.md5sum" % filename, "%s.meta" % filename):

            if kamaki.object_exists(f):

                overwrite.append(f)

        if len(overwrite) > 0:

            if d.yesno("The following storage service object(s) already "

                       "exist(s):\n%s\nDo you want to overwrite them?" %

                       "\n".join(overwrite), width=WIDTH, defaultno=1):

                continue

        session['upload'] = filename

        break

    gauge = GaugeOutput(d, "Image Upload", "Uploading...")

    try:

        out = image.out

        out.add(gauge)

        kamaki.out = out

        try:

            if 'checksum' not in session:

                md5 = MD5(out)

                session['checksum'] = md5.compute(image.device, size)

            try:

                # Upload image file

                with open(image.device, 'rb') as f:

                    session["pithos_uri"] = \

                        kamaki.upload(f, size, filename,

                                      "Calculating block hashes",

                                      "Uploading missing blocks")

                # Upload md5sum file

                out.output("Uploading md5sum file...")

                md5str = "%s %s\n" % (session['checksum'], filename)

                kamaki.upload(StringIO.StringIO(md5str), size=len(md5str),

                              remote_path="%s.md5sum" % filename)

                out.success("done")

            except ClientError as e:

                d.msgbox(

                    "Error in storage service client: %s" % e.message,

                    title="Storage Service Client Error", width=SMALL_WIDTH)

                if 'pithos_uri' in session:

                    del session['pithos_uri']

                return False

        finally:

            out.remove(gauge)

    finally:

        gauge.cleanup()

    d.msgbox("Image file `%s' was successfully uploaded" % filename,

             width=SMALL_WIDTH)

    return True

def register_image(session):

    """Register image with the compute service"""

    d = session["dialog"]

    is_public = False

    if "account" not in session:

        d.msgbox("You need to select a valid cloud before you "

                 "can register an images with it", width=SMALL_WIDTH)

        return False

    if "pithos_uri" not in session:

        d.msgbox("You need to upload the image to the cloud before you can "

                 "register it", width=SMALL_WIDTH)

        return False

    while 1:

        (code, answer) = d.inputbox("Please provide a registration name:",

                                    width=WIDTH)

        if code in (d.DIALOG_CANCEL, d.DIALOG_ESC):

            return False

        name = answer.strip()

        if len(name) == 0:

            d.msgbox("Registration name cannot be empty", width=SMALL_WIDTH)

            continue

        ret = d.yesno("Make the image public?\\nA public image is accessible "

                      "by every user of the service.", defaultno=1,

                      width=WIDTH)

        if ret not in (0, 1):

            continue

        is_public = True if ret == 0 else False

        break

    metadata = {}

    metadata.update(session['metadata'])

    if 'task_metadata' in session:

        for key in session['task_metadata']:

            metadata[key] = 'yes'

    img_type = "public" if is_public else "private"

    gauge = GaugeOutput(d, "Image Registration", "Registering image...")

    try:

        out = session['image'].out

        out.add(gauge)

        try:

            try:

                out.output("Registering %s image with the cloud..." % img_type)

                kamaki = Kamaki(session['account'], out)

                result = kamaki.register(name, session['pithos_uri'], metadata,

                                         is_public)

                out.success('done')

                # Upload metadata file

                out.output("Uploading metadata file...")

                metastring = unicode(json.dumps(result, ensure_ascii=False))

                kamaki.upload(StringIO.StringIO(metastring),

                              size=len(metastring),

                              remote_path="%s.meta" % session['upload'])

                out.success("done")

                if is_public:

                    out.output("Sharing metadata and md5sum files...")

                    kamaki.share("%s.meta" % session['upload'])

                    kamaki.share("%s.md5sum" % session['upload'])

                    out.success('done')

            except ClientError as e:

                d.msgbox("Error in storage service client: %s" % e.message)

                return False

        finally:

            out.remove(gauge)

    finally:

        gauge.cleanup()

    d.msgbox("%s image `%s' was successfully registered with the cloud as `%s'"

             % (img_type.title(), session['upload'], name), width=SMALL_WIDTH)

    return True

def modify_clouds(session):

    """Modify existing cloud accounts"""

    d = session['dialog']

    while 1:

        clouds = Kamaki.get_clouds()

        if not len(clouds):

            if not add_cloud(session):

                break

            continue

        choices = []

        for (name, cloud) in clouds.items():

            descr = cloud['description'] if 'description' in cloud else ''

            choices.append((name, descr))

        (code, choice) = d.menu(

            "In this menu you can edit existing cloud accounts or add new "

            " ones. Press <Edit> to edit an existing account or <Add> to add "

            " a new one. Press <Back> or hit <ESC> when done.", height=18,

            width=WIDTH, choices=choices, menu_height=10, ok_label="Edit",

            extra_button=1, extra_label="Add", cancel="Back", help_button=1,

            title="Clouds")

        if code in (d.DIALOG_CANCEL, d.DIALOG_ESC):

            return True

        elif code == d.DIALOG_OK:  # Edit button

            edit_cloud(session, choice)

        elif code == d.DIALOG_EXTRA:  # Add button

            add_cloud(session)

def delete_clouds(session):

    """Delete existing cloud accounts"""

    d = session['dialog']

    choices = []

    for (name, cloud) in Kamaki.get_clouds().items():

        descr = cloud['description'] if 'description' in cloud else ''

        choices.append((name, descr, 0))

    if len(choices) == 0:

        d.msgbox("No available clouds to delete!", width=SMALL_WIDTH)

        return True

    (code, to_delete) = d.checklist("Choose which cloud accounts to delete:",

                                    choices=choices, width=WIDTH)

    if code in (d.DIALOG_CANCEL, d.DIALOG_ESC):

        return False

    if not len(to_delete):

        d.msgbox("Nothing selected!", width=SMALL_WIDTH)

        return False

    if not d.yesno("Are you sure you want to remove the selected cloud "

                   "accounts?", width=WIDTH, defaultno=1):

        for i in to_delete:

            Kamaki.remove_cloud(i)

            if 'cloud' in session and session['cloud'] == i:

                del session['cloud']

                if 'account' in session:

                    del session['account']

    else:

        return False

    d.msgbox("%d cloud accounts were deleted." % len(to_delete),

             width=SMALL_WIDTH)

    return True

def kamaki_menu(session):

    """Show kamaki related actions"""

    d = session['dialog']

    default_item = "Cloud"

    if 'cloud' not in session:

        cloud = Kamaki.get_default_cloud_name()

        if cloud:

            session['cloud'] = cloud

            session['account'] = Kamaki.get_account(cloud)

            if not session['account']:

                del session['account']

        else:

            default_item = "Add/Edit"

    while 1:

        cloud = session["cloud"] if "cloud" in session else "<none>"

        if 'account' not in session and 'cloud' in session:

            cloud += " <invalid>"

        upload = session["upload"] if "upload" in session else "<none>"

        choices = [("Add/Edit", "Add/Edit cloud accounts"),

                   ("Delete", "Delete existing cloud accounts"),

                   ("Cloud", "Select cloud account to use: %s" % cloud),

                   ("Upload", "Upload image to the cloud"),

                   ("Register", "Register image with the cloud: %s" % upload)]

        (code, choice) = d.menu(

            text="Choose one of the following or press <Back> to go back.",

            width=WIDTH, choices=choices, cancel="Back", height=13,

            menu_height=5, default_item=default_item,

            title="Image Registration Menu")

        if code in (d.DIALOG_CANCEL, d.DIALOG_ESC):

            return False

        if choice == "Add/Edit":

            if modify_clouds(session):

                default_item = "Cloud"

        elif choice == "Delete":

            if delete_clouds(session):

                if len(Kamaki.get_clouds()):

                    default_item = "Cloud"

                else:

                    default_time = "Add/Edit"

            else:

                default_time = "Delete"

        elif choice == "Cloud":

            default_item = "Cloud"

            clouds = Kamaki.get_clouds()

            if not len(clouds):

                d.msgbox("No clouds available. Please add a new cloud!",

                         width=SMALL_WIDTH)

                default_item = "Add/Edit"

                continue

            if 'cloud' not in session:

                session['cloud'] = clouds.keys()[0]

            choices = []

            for name, info in clouds.items():

                default = 1 if session['cloud'] == name else 0

                descr = info['description'] if 'description' in info else ""

                choices.append((name, descr, default))

            (code, answer) = d.radiolist("Please select a cloud:",

                                         width=WIDTH, choices=choices)

            if code in (d.DIALOG_CANCEL, d.DIALOG_ESC):

                continue

            else:

                session['account'] = Kamaki.get_account(answer)

                if session['account'] is None:  # invalid account

                    if not d.yesno("The cloud %s' is not valid! Would you "

                                   "like to edit it?" % answer, width=WIDTH):

                        if edit_cloud(session, answer):

                            session['account'] = Kamaki.get_account(answer)

                            Kamaki.set_default_cloud(answer)

                if session['account'] is not None:

                    session['cloud'] = answer

                    Kamaki.set_default_cloud(answer)

                    default_item = "Upload"

                else:

                    del session['account']

                    del session['cloud']

        elif choice == "Upload":

            if upload_image(session):

                default_item = "Register"

            else:

                default_item = "Upload"

        elif choice == "Register":

            if register_image(session):

                return True

            else:

                default_item = "Register"

def add_property(session):

    """Add a new property to the image"""

    d = session['dialog']

    while 1:

        (code, answer) = d.inputbox("Please provide a name for a new image"

                                    " property:", width=WIDTH)

        if code in (d.DIALOG_CANCEL, d.DIALOG_ESC):

            return False

        name = answer.strip()

        if len(name) == 0:

            d.msgbox("A property name cannot be empty", width=SMALL_WIDTH)

            continue

        break

    while 1:

        (code, answer) = d.inputbox("Please provide a value for image "

                                    "property %s" % name, width=WIDTH)

        if code in (d.DIALOG_CANCEL, d.DIALOG_ESC):

            return False

        value = answer.strip()

        if len(value) == 0:

            d.msgbox("Value cannot be empty", width=SMALL_WIDTH)

            continue

        break

    session['metadata'][name] = value

    return True

def modify_properties(session):

    """Modify an existing image property"""

    d = session['dialog']

    while 1:

        choices = []

        for (key, val) in session['metadata'].items():

            choices.append((str(key), str(val)))

        (code, choice) = d.menu(

            "In this menu you can edit existing image properties or add new "

            "ones. Be careful! Most properties have special meaning and "

            "alter the image deployment behaviour. Press <HELP> to see more "

            "information about image properties. Press <BACK> when done.",

            height=18, width=WIDTH, choices=choices, menu_height=10,

            ok_label="Edit", extra_button=1, extra_label="Add", cancel="Back",

            help_button=1, title="Image Properties")

        if code in (d.DIALOG_CANCEL, d.DIALOG_ESC):

            return True

        # Edit button

        elif code == d.DIALOG_OK:

            (code, answer) = d.inputbox("Please provide a new value for the "

                                        "image property with name `%s':" %

                                        choice,

                                        init=session['metadata'][choice],

                                        width=WIDTH)

            if code not in (d.DIALOG_CANCEL, d.DIALOG_ESC):

                value = answer.strip()

                if len(value) == 0:

                    d.msgbox("Value cannot be empty!")

                    continue

                else:

                    session['metadata'][choice] = value

        # ADD button

        elif code == d.DIALOG_EXTRA:

            add_property(session)

        elif code == 'help':

            help_file = get_help_file("image_properties")

            assert os.path.exists(help_file)

            d.textbox(help_file, title="Image Properties", width=70, height=40)

def delete_properties(session):

    """Delete an image property"""

    d = session['dialog']

    choices = []

    for (key, val) in session['metadata'].items():

        choices.append((key, "%s" % val, 0))

    (code, to_delete) = d.checklist("Choose which properties to delete:",

                                    choices=choices, width=WIDTH)

    # If the user exits with ESC or CANCEL, the returned tag list is empty.

    for i in to_delete:

        del session['metadata'][i]

    cnt = len(to_delete)

    if cnt > 0:

        d.msgbox("%d image properties were deleted." % cnt, width=SMALL_WIDTH)

        return True

    else:

        return False

def exclude_tasks(session):

    """Exclude specific tasks from running during image deployment"""

    d = session['dialog']

    index = 0

    displayed_index = 1

    choices = []

    mapping = {}

    if 'excluded_tasks' not in session:

        session['excluded_tasks'] = []

    if -1 in session['excluded_tasks']:

        if not d.yesno("Image deployment configuration is disabled. "

                       "Do you wish to enable it?", width=SMALL_WIDTH):

            session['excluded_tasks'].remove(-1)

        else:

            return False

    for (msg, task, osfamily) in CONFIGURATION_TASKS:

        if session['metadata']['OSFAMILY'] in osfamily:

            checked = 1 if index in session['excluded_tasks'] else 0

            choices.append((str(displayed_index), msg, checked))

            mapping[displayed_index] = index

            displayed_index += 1

        index += 1

    while 1:

        (code, tags) = d.checklist(

            text="Please choose which configuration tasks you would like to "

                 "prevent from running during image deployment. "

                 "Press <No Config> to supress any configuration. "

                 "Press <Help> for more help on the image deployment "

                 "configuration tasks.",

            choices=choices, height=19, list_height=8, width=WIDTH,

            help_button=1, extra_button=1, extra_label="No Config",

            title="Exclude Configuration Tasks")

        if code in (d.DIALOG_CANCEL, d.DIALOG_ESC):

            return False

        elif code == d.DIALOG_HELP:

            help_file = get_help_file("configuration_tasks")

            assert os.path.exists(help_file)

            d.textbox(help_file, title="Configuration Tasks",

                      width=70, height=40)

        # No Config button

        elif code == d.DIALOG_EXTRA:

            session['excluded_tasks'] = [-1]

            session['task_metadata'] = ["EXCLUDE_ALL_TASKS"]

            break

        elif code == d.DIALOG_OK:

            session['excluded_tasks'] = []

            for tag in tags:

                session['excluded_tasks'].append(mapping[int(tag)])

            exclude_metadata = []

            for task in session['excluded_tasks']:

                exclude_metadata.extend(CONFIGURATION_TASKS[task][1])

            session['task_metadata'] = map(lambda x: "EXCLUDE_TASK_%s" % x,

                                           exclude_metadata)

            break

    return True

def sysprep_params(session):

    d = session['dialog']

    image = session['image']

    available = image.os.sysprep_params

    needed = image.os.needed_sysprep_params()

    if len(needed) == 0:

        return True

    fields = []

    for param in needed:

        default = available[param.name] if param.name in available else ""

        fields.append(("%s: " % param.description, default, param.length))

    txt = "Please provide the following system preparation parameters:"

    code, output = d.form(txt, height=13, width=WIDTH, form_height=len(fields),

                          fields=fields)

    if code in (d.DIALOG_CANCEL, d.DIALOG_ESC):

        return False

    sysprep_params = {}

    for i in range(len(fields)):

        if needed[i].validator(output[i]):

            image.os.sysprep_params[needed[i].name] = output[i]

        else:

            d.msgbox("The value you provided for parameter: %s is not valid" %

                     name, width=SMALL_WIDTH)

            return False

    return True

def sysprep(session):

    """Perform various system preperation tasks on the image"""

    d = session['dialog']

    image = session['image']

    # Is the image already shrinked?

    if 'shrinked' in session and session['shrinked']:

        msg = "It seems you have shrinked the image. Running system " \

              "preparation tasks on a shrinked image is dangerous."

        if d.yesno("%s\n\nDo you really want to continue?" % msg,

                   width=SMALL_WIDTH, defaultno=1):

            return

    wrapper = textwrap.TextWrapper(width=WIDTH - 5)

    help_title = "System Preperation Tasks"

    sysprep_help = "%s\n%s\n\n" % (help_title, '=' * len(help_title))

    syspreps = image.os.list_syspreps()

    if len(syspreps) == 0:

        d.msgbox("No system preparation task available to run!",

                 title="System Preperation", width=SMALL_WIDTH)

        return

    while 1:

        choices = []

        index = 0

        for sysprep in syspreps:

            name, descr = image.os.sysprep_info(sysprep)

            display_name = name.replace('-', ' ').capitalize()

            sysprep_help += "%s\n" % display_name

            sysprep_help += "%s\n" % ('-' * len(display_name))

            sysprep_help += "%s\n\n" % wrapper.fill(" ".join(descr.split()))

            enabled = 1 if sysprep.enabled else 0

            choices.append((str(index + 1), display_name, enabled))

            index += 1

        (code, tags) = d.checklist(

            "Please choose which system preparation tasks you would like to "

            "run on the image. Press <Help> to see details about the system "

            "preparation tasks.", title="Run system preparation tasks",

            choices=choices, width=70, ok_label="Run", help_button=1)

        if code in (d.DIALOG_CANCEL, d.DIALOG_ESC):

            return False

        elif code == d.DIALOG_HELP:

            d.scrollbox(sysprep_help, width=WIDTH)

        elif code == d.DIALOG_OK:

            # Enable selected syspreps and disable the rest

            for i in range(len(syspreps)):

                if str(i + 1) in tags:

                    image.os.enable_sysprep(syspreps[i])

                else:

                    image.os.disable_sysprep(syspreps[i])

            if len([s for s in image.os.list_syspreps() if s.enabled]) == 0:

                d.msgbox("No system preperation task is selected!",

                         title="System Preperation", width=SMALL_WIDTH)

                continue

            if not sysprep_params(session):

                continue

            infobox = InfoBoxOutput(d, "Image Configuration")

            try:

                image.out.add(infobox)

                try:

                    # The checksum is invalid. We have mounted the image rw

                    if 'checksum' in session:

                        del session['checksum']

                    # Monitor the metadata changes during syspreps

                    with MetadataMonitor(session, image.os.meta):

                        try:

                            image.os.do_sysprep()

                            infobox.finalize()

                        except FatalError as e:

                            title = "System Preparation"

                            d.msgbox("System Preparation failed: %s" % e,

                                     title=title, width=SMALL_WIDTH)

                finally:

                    image.out.remove(infobox)

            finally:

                infobox.cleanup()

            break

    return True

def shrink(session):

    """Shrink the image"""

    d = session['dialog']

    image = session['image']

    shrinked = 'shrinked' in session and session['shrinked']

    if shrinked:

        d.msgbox("The image is already shrinked!", title="Image Shrinking",

                 width=SMALL_WIDTH)

        return True

    msg = "This operation will shrink the last partition of the image to " \

          "reduce the total image size. If the last partition is a swap " \

          "partition, then this partition is removed and the partition " \

          "before that is shrinked. The removed swap partition will be " \

          "recreated during image deployment."

    if not d.yesno("%s\n\nDo you want to continue?" % msg, width=WIDTH,

                   height=12, title="Image Shrinking"):

        with MetadataMonitor(session, image.meta):

            infobox = InfoBoxOutput(d, "Image Shrinking", height=4)

            image.out.add(infobox)

            try:

                image.shrink()

                infobox.finalize()

            finally:

                image.out.remove(infobox)

        session['shrinked'] = True

        update_background_title(session)

    else:

        return False

    return True

def customization_menu(session):

    """Show image customization menu"""

    d = session['dialog']

    choices = [("Sysprep", "Run various image preparation tasks"),

               ("Shrink", "Shrink image"),

               ("View/Modify", "View/Modify image properties"),

               ("Delete", "Delete image properties"),

               ("Exclude", "Exclude various deployment tasks from running")]

    default_item = 0

    actions = {"Sysprep": sysprep,

               "Shrink": shrink,

               "View/Modify": modify_properties,

               "Delete": delete_properties,

               "Exclude": exclude_tasks}

    while 1:

        (code, choice) = d.menu(

            text="Choose one of the following or press <Back> to exit.",

            width=WIDTH, choices=choices, cancel="Back", height=13,

            menu_height=len(choices), default_item=choices[default_item][0],

            title="Image Customization Menu")

        if code in (d.DIALOG_CANCEL, d.DIALOG_ESC):

            break

        elif choice in actions:

            default_item = [entry[0] for entry in choices].index(choice)

            if actions[choice](session):

                default_item = (default_item + 1) % len(choices)

def main_menu(session):

    """Show the main menu of the program"""

    d = session['dialog']

    update_background_title(session)

    choices = [("Customize", "Customize image & cloud deployment options"),

               ("Register", "Register image to a cloud"),

               ("Extract", "Dump image to local file system"),

               ("Reset", "Reset everything and start over again"),

               ("Help", "Get help for using snf-image-creator")]

    default_item = "Customize"

    actions = {"Customize": customization_menu, "Register": kamaki_menu,

               "Extract": extract_image}

    while 1:

        (code, choice) = d.menu(

            text="Choose one of the following or press <Exit> to exit.",

            width=WIDTH, choices=choices, cancel="Exit", height=13,

            default_item=default_item, menu_height=len(choices),

            title="Image Creator for synnefo (snf-image-creator version %s)" %

                  version)

        if code in (d.DIALOG_CANCEL, d.DIALOG_ESC):

            if confirm_exit(d):

                break

        elif choice == "Reset":

            if confirm_reset(d):

                d.infobox("Resetting snf-image-creator. Please wait...",

                          width=SMALL_WIDTH)

                raise Reset

        elif choice == "Help":

            d.msgbox("For help, check the online documentation:\n\nhttp://www"

                     ".synnefo.org/docs/snf-image-creator/latest/",

                     width=WIDTH, title="Help")

        elif choice in actions:

            actions[choice](session)

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