Synnefo

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from datetime import datetime

from django.db.models import Q

from astakos.quotaholder_app.exception import (

    QuotaholderError,

    NoCommissionError,

    CorruptedError,

    NoHoldingError,

    DuplicateError)

from astakos.quotaholder_app.commission import (

    Import, Release, Operations, finalize, undo)

from astakos.quotaholder_app.models import (

    Holding, Commission, Provision, ProvisionLog)

def format_datetime(d):

    return d.strftime('%Y-%m-%dT%H:%M:%S.%f')[:24]

def get_quota(holders=None, sources=None, resources=None, flt=None):

    if flt is None:

        flt = Q()

    holdings = Holding.objects.filter(flt)

    if holders is not None:

        holdings = holdings.filter(holder__in=holders)

    if sources is not None:

        holdings = holdings.filter(source__in=sources)

    if resources is not None:

        holdings = holdings.filter(resource__in=resources)

    quotas = {}

    for holding in holdings:

        key = (holding.holder, holding.source, holding.resource)

        value = (holding.limit, holding.usage_min, holding.usage_max)

        quotas[key] = value

    return quotas

def delete_quota(keys):

    for holder, source, resource in keys:

        Holding.objects.filter(holder=holder,

                               source=source,

                               resource=resource).delete()

def _get_holdings_for_update(holding_keys, resource=None, delete=False):

    flt = Q(resource=resource) if resource is not None else Q()

    holders = set(holder for (holder, source, resource) in holding_keys)

    objs = Holding.objects.filter(flt, holder__in=holders).order_by('pk')

    hs = objs.select_for_update()

    keys = set(holding_keys)

    holdings = {}

    put_back = []

    for h in hs:

        key = h.holder, h.source, h.resource

        if key in keys:

            holdings[key] = h

        else:

            put_back.append(h)

    if delete:

        objs.delete()

        Holding.objects.bulk_create(put_back)

    return holdings

def _mkProvision(key, quantity):

    holder, source, resource = key

    return {'holder': holder,

            'source': source,

            'resource': resource,

            'quantity': quantity,

            }

def set_quota(quotas, resource=None):

    holding_keys = [key for (key, limit) in quotas]

    holdings = _get_holdings_for_update(

        holding_keys, resource=resource, delete=True)

    new_holdings = {}

    for key, limit in quotas:

        holder, source, res = key

        if resource is not None and resource != res:

            continue

        h = Holding(holder=holder,

                    source=source,

                    resource=res,

                    limit=limit)

        try:

            h_old = holdings[key]

            h.usage_min = h_old.usage_min

            h.usage_max = h_old.usage_max

            h.id = h_old.id

        except KeyError:

            pass

        new_holdings[key] = h

    Holding.objects.bulk_create(new_holdings.values())

def issue_commission(clientkey, provisions, name="", force=False):

    operations = Operations()

    provisions_to_create = []

    keys = [key for (key, value) in provisions]

    holdings = _get_holdings_for_update(keys)

    try:

        checked = []

        for key, quantity in provisions:

            if key in checked:

                m = "Duplicate provision for %s" % str(key)

                provision = _mkProvision(key, quantity)

                raise DuplicateError(m,

                                     provision=provision)

            checked.append(key)

            # Target

            try:

                th = holdings[key]

            except KeyError:

                m = ("There is no such holding %s" % str(key))

                provision = _mkProvision(key, quantity)

                raise NoHoldingError(m,

                                     provision=provision)

            if quantity >= 0:

                operations.prepare(Import, th, quantity, force)

            else:  # release

                abs_quantity = -quantity

                operations.prepare(Release, th, abs_quantity, False)

            holdings[key] = th

            provisions_to_create.append((key, quantity))

    except QuotaholderError:

        operations.revert()

        raise

    commission = Commission.objects.create(clientkey=clientkey,

                                           name=name,

                                           issue_datetime=datetime.now())

    for (holder, source, resource), quantity in provisions_to_create:

        Provision.objects.create(serial=commission,

                                 holder=holder,

                                 source=source,

                                 resource=resource,

                                 quantity=quantity)

    return commission.serial

def _log_provision(commission, provision, holding, log_datetime, reason):

    kwargs = {

        'serial':              commission.serial,

        'name':                commission.name,

        'holder':              holding.holder,

        'source':              holding.source,

        'resource':            holding.resource,

        'limit':               holding.limit,

        'usage_min':           holding.usage_min,

        'usage_max':           holding.usage_max,

        'delta_quantity':      provision.quantity,

        'issue_time':          format_datetime(commission.issue_datetime),

        'log_time':            format_datetime(log_datetime),

        'reason':              reason,

    }

    ProvisionLog.objects.create(**kwargs)

def _get_commissions_for_update(clientkey, serials):

    cs = Commission.objects.filter(

        clientkey=clientkey, serial__in=serials).select_for_update()

    commissions = {}

    for c in cs:

        commissions[c.serial] = c

    return commissions

def _partition_by(f, l):

    d = {}

    for x in l:

        group = f(x)

        group_l = d.get(group, [])

        group_l.append(x)

        d[group] = group_l

    return d

def resolve_pending_commissions(clientkey, accept_set=None, reject_set=None,

                                reason=''):

    if accept_set is None:

        accept_set = []

    if reject_set is None:

        reject_set = []

    actions = dict.fromkeys(accept_set, True)

    conflicting = set()

    for serial in reject_set:

        if actions.get(serial) is True:

            actions.pop(serial)

            conflicting.add(serial)

        else:

            actions[serial] = False

    conflicting = list(conflicting)

    serials = actions.keys()

    commissions = _get_commissions_for_update(clientkey, serials)

    ps = Provision.objects.filter(serial__in=serials).select_for_update()

    holding_keys = sorted(p.holding_key() for p in ps)

    holdings = _get_holdings_for_update(holding_keys)

    provisions = _partition_by(lambda p: p.serial_id, ps)

    log_datetime = datetime.now()

    accepted, rejected, notFound = [], [], []

    for serial, accept in actions.iteritems():

        commission = commissions.get(serial)

        if commission is None:

            notFound.append(serial)

            continue

        accepted.append(serial) if accept else rejected.append(serial)

        ps = provisions.get(serial, [])

        for pv in ps:

            key = pv.holding_key()

            h = holdings.get(key)

            if h is None:

                raise CorruptedError("Corrupted provision")

            quantity = pv.quantity

            action = finalize if accept else undo

            if quantity >= 0:

                action(Import, h, quantity)

            else:  # release

                action(Release, h, -quantity)

            prefix = 'ACCEPT:' if accept else 'REJECT:'

            comm_reason = prefix + reason[-121:]

            _log_provision(commission, pv, h, log_datetime, comm_reason)

            pv.delete()

        commission.delete()

    return accepted, rejected, notFound, conflicting

def resolve_pending_commission(clientkey, serial, accept=True):

    if accept:

        ok, notOk, notF, confl = resolve_pending_commissions(

            clientkey=clientkey, accept_set=[serial])

    else:

        notOk, ok, notF, confl = resolve_pending_commissions(

            clientkey=clientkey, reject_set=[serial])

    assert notOk == confl == []

    assert ok + notF == [serial]

    return bool(ok)

def get_pending_commissions(clientkey):

    pending = Commission.objects.filter(clientkey=clientkey)

    pending_list = pending.values_list('serial', flat=True)

    return list(pending_list)

def get_commission(clientkey, serial):

    try:

        commission = Commission.objects.get(clientkey=clientkey,

                                            serial=serial)

    except Commission.DoesNotExist:

        raise NoCommissionError(serial)

    objs = Provision.objects

    provisions = objs.filter(serial=commission)

    ps = [p.todict() for p in provisions]

    response = {'serial':     serial,

                'provisions': ps,

                'issue_time': commission.issue_datetime,

                'name':       commission.name,

                }

    return response