source: main/waeup.sirp/trunk/src/waeup/sirp/accesscodes/accesscodes.py @ 6416

"""Components to handle access codes.
"""
import csv
import grok
import os
from BTrees.OIBTree import OIBTree
from datetime import datetime
from hurry.workflow.interfaces import (
    IWorkflowInfo, InvalidTransitionError, IWorkflowState)
from random import SystemRandom as random
from waeup.sirp.interfaces import IWAeUPSIRPPluggable
from waeup.sirp.accesscodes.interfaces import (
    IAccessCode, IAccessCodeBatch, IAccessCodeBatchContainer
    )
from waeup.sirp.accesscodes.workflow import DISABLED, USED

class ManageACBatches(grok.Permission):
    grok.name('waeup.manageACBatches')

class AccessCode(grok.Model):
    grok.implements(IAccessCode)

    def __init__(self, batch_serial, random_num):
        self.batch_serial = batch_serial
        self.random_num = random_num
        IWorkflowInfo(self).fireTransition('init')

    @property
    def representation(self):
        return '%s-%s-%s' % (
            self.batch_prefix, self.batch_num, self.random_num)

    @property
    def batch(self):
        return getattr(self, '__parent__', None)

    @property
    def batch_prefix(self):
        if self.batch is None:
            return ''
        return self.batch.prefix

    @property
    def batch_num(self):
        if self.batch is None:
            return ''
        return self.batch.num

    @property
    def cost(self):
        if self.batch is None:
            return None
        return self.batch.cost

    @property
    def disabled(self):
        return IWorkflowState(self).getState() == DISABLED

    @property
    def used(self):
        return IWorkflowState(self).getState() == USED

class AccessCodeBatch(grok.Model):
    """A batch of access codes.
    """
    grok.implements(IAccessCodeBatch)

    def __init__(self, creation_date, creator, batch_prefix, cost,
                 entry_num, num=None):
        super(AccessCodeBatch, self).__init__()
        self.creation_date = creation_date
        self.creator = creator
        self.prefix = batch_prefix.upper()
        self.cost = cost
        self.entry_num = entry_num
        self.num = num
        self.invalidated_num = 0
        self.disabled_num = 0
        self._entries = list()
        self._acids = OIBTree()
        self._createEntries()

    def _createEntries(self):
        """Create the entries for this batch.
        """
        for num, pin in enumerate(self._getNewRandomNum(num=self.entry_num)):
            self.addAccessCode(num, pin)
        return

    def _getNewRandomNum(self, num=1):
        """Create a set of ``num`` random numbers of 10 digits each.

        The number is returned as string.
        """
        curr = 1
        while curr <= num:
            pin = ''
            for x in range(10):
                pin += str(random().randint(0, 9))
            if not '%s-%s-%s' % (self.prefix, self.num, pin) in self._acids:
                curr += 1
                yield pin
            # PIN already in use

    def _getStoragePath(self):
        """Get the directory, where we store all batch-related CSV files.
        """
        site = grok.getSite()
        storagepath = site['datacenter'].storage
        ac_storage = os.path.join(storagepath, 'accesscodes')
        if not os.path.exists(ac_storage):
            os.mkdir(ac_storage)
        return ac_storage

    def entries(self):
        """Get all entries of this batch as generator.
        """
        for x in self._entries:
            yield x

    def getAccessCode(self, ac_id):
        """Get the AccessCode with ID ``ac_id`` or ``KeyError``.
        """
        return self._entries[self._acids[ac_id]]

    def addAccessCode(self, num, pin):
        """Add an access-code.
        """
        ac = AccessCode(num, pin)
        ac.__parent__ = self
        self._entries.append(ac)
        self._acids.update({ac.representation: num})
        return

    def invalidate(self, ac_id, student_id=None):
        """Invalidate the AC with ID ``ac_id``.
        """
        num = self._acids[ac_id]
        self.invalidated_num += 1

    def disable(self, ac_id, user_id=None):
        """Disable the AC with ID ``ac_id``.

        ``user_id`` is the user ID of the user triggering the
        process. Already disabled ACs are left untouched.
        """
        num = self._acids[ac_id]
        ac = self.getAccessCode(ac_id)
        if ac._disabled == True:
            return
        self.disabled_num += 1

    def enable(self, ac_id):
        """(Re-)enable the AC with ID ``ac_id``.

        This leaves the given AC in state ``unused``. Already enabled
        ACs are left untouched.
        """
        num = self._acids[ac_id]
        self.disabled_num -= 1

    def createCSVLogFile(self):
        """Create a CSV file with data in batch.

        Data will not contain invalidation date nor student ids.  File
        will be created in ``accesscodes`` subdir of data center
        storage path.

        Returns name of created file.
        """
        date = self.creation_date.strftime('%Y_%m_%d_%H_%M_%S')
        ac_storage = self._getStoragePath()
        csv_path = os.path.join(
            ac_storage, '%s-%s-%s-%s.csv' % (
                self.prefix, self.num, date, self.creator)
            )
        writer = csv.writer(open(csv_path, 'w'), quoting=csv.QUOTE_ALL)
        writer.writerow(['serial', 'ac', 'cost'])
        writer.writerow([self.prefix, str(self.num), "%0.2f" % self.cost])

        for value in self._entries:
            writer.writerow(
                [str(value.batch_serial), str(value.representation)]
                )
        site = grok.getSite()
        logger = site.logger
        logger.info(
            "Created batch %s-%s" % (self.prefix, self.num))
        logger.info(
            "Written batch CSV to %s" % csv_path)
        return os.path.basename(csv_path)

    def archive(self):
        """Create a CSV file for archive.
        """
        ac_storage = self._getStoragePath()
        now = datetime.now()
        timestamp = now.strftime('%Y_%m_%d_%H_%M_%S')
        csv_path = os.path.join(
            ac_storage, '%s-%s_archive-%s-%s.csv' % (
                self.prefix, self.num, timestamp, self.creator)
            )
        writer = csv.writer(open(csv_path, 'w'), quoting=csv.QUOTE_ALL)
        writer.writerow(['prefix', 'serial', 'ac', 'date'])
        writer.writerow([self.prefix, '%0.2f' % self.cost, str(self.num),
                         str(self.entry_num)])
        for value in self._entries:
            writer.writerow([
                    self.prefix, value.batch_serial, value.representation,
                    ])
        return os.path.basename(csv_path)

    def search(self, searchterm, searchtype):
        if searchtype == 'serial':
            if len(self._entries) < searchterm + 1:
                return []
            return [self._entries[searchterm]]
        if searchtype == 'pin':
            try:
                entry = self.getAccessCode(searchterm)
                return [entry]
            except KeyError:
                return []

class AccessCodeBatchContainer(grok.Container):
    grok.implements(IAccessCodeBatchContainer)

    def _getStoragePath(self):
        """Get the directory, where batch import files are stored.
        """
        site = grok.getSite()
        storagepath = site['datacenter'].storage
        ac_storage = os.path.join(storagepath, 'accesscodes')
        import_path = os.path.join(ac_storage, 'imports')
        if not os.path.exists(import_path):
            os.mkdir(import_path)
        return import_path

    def addBatch(self, batch):
        """Add a batch.
        """
        batch.num = self.getNum(batch.prefix)
        key = "%s-%s" % (batch.prefix, batch.num)
        self[key] = batch
        self._p_changed = True

    def createBatch(self, creation_date, creator, batch_prefix, cost,
                    entry_num):
        """Create and add a batch.
        """
        batch_num = self.getNum(batch_prefix)
        batch = AccessCodeBatch(creation_date, creator, batch_prefix,
                                cost, entry_num, num=batch_num)
        self.addBatch(batch)
        return batch

    def getNum(self, prefix):
        """Get next unused num for given prefix.
        """
        num = 1
        while self.get('%s-%s' % (prefix, num), None) is not None:
            num += 1
        return num

    def getImportFiles(self):
        """Return a generator with basenames of available import files.
        """
        path = self._getStoragePath()
        for filename in sorted(os.listdir(path)):
            yield filename

    def reimport(self, filename, creator=u'UNKNOWN'):
        """Reimport a batch given in CSV file.

        CSV file must be of format as generated by createCSVLogFile
        method.
        """
        path = os.path.join(self._getStoragePath(), filename)
        reader = csv.DictReader(open(path, 'rb'), quoting=csv.QUOTE_ALL)
        entry = reader.next()
        cost = float(entry['cost'])
        num = int(entry['ac'])
        batch_name = '%s-%s' % (entry['serial'], num)
        if batch_name in self.keys():
            raise KeyError('Batch already exists: %s' % batch_name)
        batch = AccessCodeBatch(
            datetime.now(), creator, entry['serial'], cost, 0, num=num)
        num_entries = 0
        for row in reader:
            pin = row['ac']
            serial = int(row['serial'])
            rand_num = pin.rsplit('-', 1)[-1]
            batch.addAccessCode(serial, rand_num)
            num_entries += 1
        batch.entry_num = num_entries
        self[batch_name] = batch
        batch.createCSVLogFile()
        return

    def search(self, searchterm, searchtype, ):
        """Look for access-codes that comply with the given params.
        """
        results = []
        if searchtype == 'serial':
            try:
                searchterm = int(searchterm)
            except:
                return []
        for batchname in self.keys():
            part_result = self[batchname].search(searchterm, searchtype)
            results.extend(part_result)
        return results

    def getAccessCode(self, ac_id):
        """Get the AccessCode with ID ``ac_id`` or ``KeyError``.
        """
        for batchname in self.keys():
            batch = self[batchname]
            try:
                return batch.getAccessCode(ac_id)
            except KeyError:
                continue
        return None

    def disable(self, ac_id, user_id):
        """Disable the AC with ID ``ac_id``.

        ``user_id`` is the user ID of the user triggering the
        process. Already disabled ACs are left untouched.
        """
        ac = self.getAccessCode(ac_id)
        if ac is None:
            return
        ac.__parent__.disable(ac_id, user_id)
        return

    def enable(self, ac_id):
        """(Re-)enable the AC with ID ``ac_id``.

        This leaves the given AC in state ``unused``. Already enabled
        ACs are left untouched.
        """
        ac = self.getAccessCode(ac_id)
        if ac is None:
            return
        ac.__parent__.enable(ac_id)
        return

    def invalidate(self, ac_id):
        """Invalidate the AC with ID ``ac_id``.
        """
        ac = self.getAccessCode(ac_id)
        if ac is None:
            return
        ac.__parent__.invalidate(ac_id)
        return


class AccessCodePlugin(grok.GlobalUtility):
    grok.name('accesscodes')
    grok.implements(IWAeUPSIRPPluggable)

    def setup(self, site, name, logger):
        site['accesscodes'] = AccessCodeBatchContainer()
        logger.info('Installed container for access code batches.')
        return

    def update(self, site, name, logger):
        if not 'accesscodes' in site.keys():
            logger.info('Updating site at %s. Installing access codes.' % (
                    site,))
            self.setup(site, name, logger)
        else:
            logger.info(
                'AccessCodePlugin: Updating site at %s: Nothing to do.' % (
                    site, ))
        return

def get_access_code(access_code):
    """Get an access code instance.

    An access code here is a string like ``PUDE-1-1234567890``.

    Returns ``None`` if the given code cannot be found.

    This is a convenicence function that is faster than looking up a
    batch container for the approriate access code.
    """
    site = grok.getSite()
    if not isinstance(access_code, basestring):
        return None
    try:
        batch_id, ac_id = access_code.rsplit('-', 1)
    except:
        return None
    batch = site['accesscodes'].get(batch_id, None)
    if batch is None:
        return None
    try:
        code = batch.getAccessCode(access_code)
    except KeyError:
        return None
    return code

def fire_transition(access_code, arg, toward=False):
    """Fire workflow transition for access code.

    The access code instance is looked up via `access_code` (a string
    like ``APP-1-12345678``).

    `arg` tells what kind of transition to trigger. This will be a
    transition id like ``'use'`` or ``'init'``, or some transition
    target like :var:`waeup.sirp.accesscodes.workflow.INITIALIZED`.

    If `toward` is ``False`` (the default) you have to pass a
    transition id as `arg`, otherwise you must give a transition
    target.

    :func:`fire_transition` might raise exceptions depending on the
    reason why the requested transition cannot be performed.

    The following exceptions can occur during processing:

    :exc:`KeyError`:
      signals not existent access code, batch or site.

    :exc:`ValueError`:
      signals illegal format of `access_code` string. The regular format is
      ``APP-N-XXXXXXXX``.

    :exc:`hurry.workflow.interfaces.InvalidTransitionError`:
      the transition requested cannot be performed because the workflow
      rules forbid it.

    :exc:`Unauthorized`:
      the current user is not allowed to perform the requested transition.

    """
    try:
        batch_id, ac_id = access_code.rsplit('-', 1)
    except ValueError:
        raise ValueError(
            'Invalid access code format: %s (use: APP-N-XXXXXXXX)' % (
                access_code,))
    try:
        ac = grok.getSite()['accesscodes'][batch_id].getAccessCode(access_code)
    except TypeError:
        raise KeyError(
            'No site available for looking up accesscodes')
    info = IWorkflowInfo(ac)
    if toward:
        info.fireTransitionToward(arg)
    else:
        info.fireTransition(arg)
    return True

def invalidate_accesscode(access_code):
    """Invalidate AccessCode denoted by string ``access_code``.

    Fires an appropriate transition to perform the task.

    See :func:`fire_transition` for possible exceptions and their
    meanings.
    """
    return fire_transition(access_code, 'use')

def disable_accesscode(access_code):
    """Disable AccessCode denoted by string ``access_code``.

    Fires an appropriate transition to perform the task.

    See :func:`fire_transition` for possible exceptions and their
    meanings.
    """
    return fire_transition(access_code, DISABLED, toward=True)

def reenable_accesscode(access_code):
    """Reenable AccessCode denoted by string ``access_code``.

    Fires an appropriate transition to perform the task.

    See :func:`fire_transition` for possible exceptions and their
    meanings.
    """
    return fire_transition(access_code, 'reenable')