Synnefo

# Copyright 2011 GRNET S.A. All rights reserved.

#

# Redistribution and use in source and binary forms, with or

# without modification, are permitted provided that the following

# conditions are met:

#

#   1. Redistributions of source code must retain the above

#      copyright notice, this list of conditions and the following

#      disclaimer.

#

#   2. Redistributions in binary form must reproduce the above

#      copyright notice, this list of conditions and the following

#      disclaimer in the documentation and/or other materials

#      provided with the distribution.

#

# THIS SOFTWARE IS PROVIDED BY GRNET S.A. ``AS IS'' AND ANY EXPRESS

# OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED

# WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR

# PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL GRNET S.A OR

# CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,

# SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT

# LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF

# USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED

# AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT

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

# ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE

# POSSIBILITY OF SUCH DAMAGE.

#

# The views and conclusions contained in the software and

# documentation are those of the authors and should not be

# interpreted as representing official policies, either expressed

# or implied, of GRNET S.A.

import json

from logging import getLogger

from string import punctuation

from StringIO import StringIO

from urllib import unquote

from django.conf import settings

from django.http import HttpResponse, HttpResponseNotFound

from synnefo.plankton.util import plankton_method

FILTERS = ('name', 'container_format', 'disk_format', 'status', 'size_min',

           'size_max')

PARAMS = ('sort_key', 'sort_dir')

SORT_KEY_OPTIONS = ('id', 'name', 'status', 'size', 'disk_format',

                    'container_format', 'created_at', 'updated_at')

SORT_DIR_OPTIONS = ('asc', 'desc')

LIST_FIELDS = ('status', 'name', 'disk_format', 'container_format', 'size',

               'id')

DETAIL_FIELDS = ('name', 'disk_format', 'container_format', 'size', 'checksum',

                 'location', 'created_at', 'updated_at', 'deleted_at',

                 'status', 'is_public', 'owner', 'properties', 'id')

ADD_FIELDS = ('name', 'id', 'store', 'disk_format', 'container_format', 'size',

              'checksum', 'is_public', 'owner', 'properties', 'location')

UPDATE_FIELDS = ('name', 'disk_format', 'container_format', 'is_public',

                 'owner', 'properties', 'status')

log = getLogger('synnefo.plankton')

def _create_image_response(image):

    response = HttpResponse()

    for key in DETAIL_FIELDS:

        if key == 'properties':

            for k, v in image.get('properties', {}).items():

                name = 'x-image-meta-property-' + k.replace('_', '-')

                response[name] = v

        else:

            name = 'x-image-meta-' + key.replace('_', '-')

            response[name] = image.get(key, '')

    return response

def _get_image_headers(request):

    def normalize(s):

        return ''.join('_' if c in punctuation else c.lower() for c in s)

    META_PREFIX = 'HTTP_X_IMAGE_META_'

    META_PREFIX_LEN = len(META_PREFIX)

    META_PROPERTY_PREFIX = 'HTTP_X_IMAGE_META_PROPERTY_'

    META_PROPERTY_PREFIX_LEN = len(META_PROPERTY_PREFIX)

    headers = {'properties': {}}

    for key, val in request.META.items():

        if key.startswith(META_PROPERTY_PREFIX):

            name = normalize(key[META_PROPERTY_PREFIX_LEN:])

            headers['properties'][unquote(name)] = unquote(val)

        elif key.startswith(META_PREFIX):

            name = normalize(key[META_PREFIX_LEN:])

            headers[unquote(name)] = unquote(val)

    is_public = headers.get('is_public', None)

    if is_public is not None:

        headers['is_public'] = True if is_public.lower() == 'true' else False

    if not headers['properties']:

        del headers['properties']

    return headers

@plankton_method('POST')

def add_image(request):

    """Add a new virtual machine image

    Described in:

    3.6. Adding a New Virtual Machine Image

    Implementation notes:

      * The implementation is very inefficient as it loads the whole image

        in memory.

    Limitations:

      * x-image-meta-id is not supported. Will always return 409 Conflict.

    Extensions:

      * An x-image-meta-location header can be passed with a link to file,

        instead of uploading the data.

    """

    params = _get_image_headers(request)

    log.debug('add_image %s', params)

    assert 'name' in params

    assert set(params.keys()).issubset(set(ADD_FIELDS))

    name = params.pop('name')

    location = params.pop('location', None)

    if location:

        image = request.backend.register(name, location, params)

    else:

        #f = StringIO(request.raw_post_data)

        #image = request.backend.put(name, f, params)

        return HttpResponse(status=501)     # Not Implemented

    if not image:

        return HttpResponse('Registration failed', status=500)

    return _create_image_response(image)

@plankton_method('PUT')

def add_image_member(request, image_id, member):

    """Add a member to an image

    Described in:

    3.9. Adding a Member to an Image

    Limitations:

      * Passing a body to enable `can_share` is not supported.

    """

    log.debug('add_image_member %s %s', image_id, member)

    request.backend.add_user(image_id, member)

    return HttpResponse(status=204)

@plankton_method('GET')

def get_image(request, image_id):

    """Retrieve a virtual machine image

    Described in:

    3.5. Retrieving a Virtual Machine Image

    Implementation notes:

      * The implementation is very inefficient as it loads the whole image

        in memory.

    """

    #image = request.backend.get_image(image_id)

    #if not image:

    #    return HttpResponseNotFound()

    #

    #response = _create_image_response(image)

    #data = request.backend.get_data(image)

    #response.content = data

    #response['Content-Length'] = len(data)

    #response['Content-Type'] = 'application/octet-stream'

    #response['ETag'] = image['checksum']

    #return response

    return HttpResponse(status=501)     # Not Implemented

@plankton_method('HEAD')

def get_image_meta(request, image_id):

    """Return detailed metadata on a specific image

    Described in:

    3.4. Requesting Detailed Metadata on a Specific Image

    """

    image = request.backend.get_image(image_id)

    if not image:

        return HttpResponseNotFound()

    return _create_image_response(image)

@plankton_method('GET')

def list_image_members(request, image_id):

    """List image memberships

    Described in:

    3.7. Requesting Image Memberships

    """

    members = [{'member_id': user, 'can_share': False}

                for user in request.backend.list_users(image_id)]

    data = json.dumps({'members': members}, indent=settings.DEBUG)

    return HttpResponse(data)

@plankton_method('GET')

def list_public_images(request, detail=False):

    """Return a list of public VM images.

    Described in:

    3.1. Requesting a List of Public VM Images

    3.2. Requesting Detailed Metadata on Public VM Images

    3.3. Filtering Images Returned via GET /images andGET /images/detail

    Extensions:

      * Image ID is returned in both compact and detail listings

    """

    def get_request_params(keys):

        params = {}

        for key in keys:

            val = request.GET.get(key, None)

            if val is not None:

                params[key] = val

        return params

    log.debug('list_public_images detail=%s', detail)

    filters = get_request_params(FILTERS)

    params = get_request_params(PARAMS)

    params.setdefault('sort_key', 'created_at')

    params.setdefault('sort_dir', 'desc')

    assert params['sort_key'] in SORT_KEY_OPTIONS

    assert params['sort_dir'] in SORT_DIR_OPTIONS

    images = request.backend.list_public(filters, params)

    # Remove keys that should not be returned

    fields = DETAIL_FIELDS if detail else LIST_FIELDS

    for image in images:

        for key in image.keys():

            if key not in fields:

                del image[key]

    data = json.dumps(images, indent=settings.DEBUG)

    return HttpResponse(data)

@plankton_method('GET')

def list_shared_images(request, member):

    """Request shared images

    Described in:

    3.8. Requesting Shared Images

    Implementation notes:

      * It is not clear what this method should do. We return the IDs of

        the users's images that are accessible by `member`.

    """

    log.debug('list_shared_images %s', member)

    images = []

    for image_id in request.backend.iter_shared(member):

        images.append({'image_id': image_id, 'can_share': False})

    data = json.dumps({'shared_images': images}, indent=settings.DEBUG)

    return HttpResponse(data)

@plankton_method('DELETE')

def remove_image_member(request, image_id, member):

    """Remove a member from an image

    Described in:

    3.10. Removing a Member from an Image

    """

    log.debug('remove_image_member %s %s', image_id, member)

    request.backend.remove_user(image_id, member)

    return HttpResponse(status=204)

@plankton_method('PUT')

def update_image(request, image_id):

    """Update an image

    Described in:

    3.6.2. Updating an Image

    Implementation notes:

      * It is not clear which metadata are allowed to be updated. We support:

        name, disk_format, container_format, is_public, owner, properties

        and status.

    """

    meta = _get_image_headers(request)

    log.debug('update_image %s', meta)

    assert set(meta.keys()).issubset(set(UPDATE_FIELDS))

    image = request.backend.update(image_id, meta)

    return _create_image_response(image)

@plankton_method('PUT')

def update_image_members(request, image_id):

    """Replace a membership list for an image

    Described in:

    3.11. Replacing a Membership List for an Image

    Limitations:

      * can_share value is ignored

    """

    log.debug('update_image_members %s', image_id)

    members = []

    try:

        data = json.loads(request.raw_post_data)

        for member in data['memberships']:

            members.append(member['member_id'])

    except (ValueError, KeyError, TypeError):

        return HttpResponse(status=400)

    request.backend.replace_users(image_id, members)

    return HttpResponse(status=204)