Files
edx-platform/lms/djangoapps/certificates/queue.py
2012-11-20 15:18:09 -05:00

263 lines
8.4 KiB
Python

from certificates.models import GeneratedCertificate
from certificates.models import certificate_status_for_student
from certificates.models import CertificateStatuses as status
from courseware import grades, courses
from django.test.client import RequestFactory
from capa.xqueue_interface import XQueueInterface
from capa.xqueue_interface import make_xheader, make_hashkey
from django.conf import settings
from requests.auth import HTTPBasicAuth
from student.models import UserProfile
import json
import random
import logging
logger = logging.getLogger(__name__)
class XQueueCertInterface(object):
"""
XQueueCertificateInterface provides an
interface to the xqueue server for
managing student certificates.
Instantiating an object will create a new
connection to the queue server.
See models.py for valid state transitions,
summary of methods:
add_cert: Add a new certificate. Puts a single
request on the queue for the student/course.
Once the certificate is generated a post
will be made to the update_certificate
view which will save the certificate
download URL.
regen_cert: Regenerate an existing certificate.
For a user that already has a certificate
this will delete the existing one and
generate a new cert.
del_cert: Delete an existing certificate
For a user that already has a certificate
this will delete his cert.
"""
def __init__(self, request=None):
# Get basic auth (username/password) for
# xqueue connection if it's in the settings
if settings.XQUEUE_INTERFACE.get('basic_auth') is not None:
requests_auth = HTTPBasicAuth(
*settings.XQUEUE_INTERFACE['basic_auth'])
else:
requests_auth = None
if request is None:
factory = RequestFactory()
self.request = factory.get('/')
else:
self.request = request
self.xqueue_interface = XQueueInterface(
settings.XQUEUE_INTERFACE['url'],
settings.XQUEUE_INTERFACE['django_auth'],
requests_auth,
)
def regen_cert(self, student, course_id):
"""
Arguments:
student - User.object
course_id - courseenrollment.course_id (string)
Removes certificate for a student, will change
the certificate status to 'regenerating'.
Certificate must be in the 'error' or 'downloadable' state
If the student has a passing grade a certificate
request will be put on the queue
If the student is not passing his state will change
to status.notpassing
otherwise it will return the current state
"""
VALID_STATUSES = [status.error, status.downloadable]
cert_status = certificate_status_for_student(
student, course_id)['status']
if cert_status in VALID_STATUSES:
# grade the student
course = courses.get_course_by_id(course_id)
grade = grades.grade(student, self.request, course)
profile = UserProfile.objects.get(user=student)
try:
cert = GeneratedCertificate.objects.get(
user=student, course_id=course_id)
except GeneratedCertificate.DoesNotExist:
logger.critical("Attempting to regenerate a certificate"
"for a user that doesn't have one")
raise
if grade['grade'] is not None:
cert.status = status.regenerating
cert.name = profile.name
contents = {
'action': 'regen',
'delete_verify_uuid': cert.verify_uuid,
'delete_download_uuid': cert.download_uuid,
'username': cert.user.username,
'course_id': cert.course_id,
'name': profile.name,
}
key = cert.key
self._send_to_xqueue(contents, key)
cert.save()
else:
cert.status = status.notpassing
cert.name = profile.name
cert.save()
return cert_status
def del_cert(self, student, course_id):
"""
Arguments:
student - User.object
course_id - courseenrollment.course_id (string)
Removes certificate for a student, will change
the certificate status to 'deleting'.
Certificate must be in the 'error' or 'downloadable' state
otherwise it will return the current state
"""
VALID_STATUSES = [status.error, status.downloadable]
cert_status = certificate_status_for_student(
student, course_id)['status']
if cert_status in VALID_STATUSES:
try:
cert = GeneratedCertificate.objects.get(
user=student, course_id=course_id)
except GeneratedCertificate.DoesNotExist:
logger.warning("Attempting to delete a certificate"
"for a user that doesn't have one")
raise
cert.status = status.deleting
contents = {
'action': 'delete',
'delete_verify_uuid': cert.verify_uuid,
'delete_download_uuid': cert.download_uuid,
'username': cert.user.username,
}
key = cert.key
self._send_to_xqueue(contents, key)
cert.save()
return cert_status
def add_cert(self, student, course_id):
"""
Arguments:
student - User.object
course_id - courseenrollment.course_id (string)
Request a new certificate for a student.
Will change the certificate status to 'deleting'.
Certificate must be in the 'unavailable', 'error',
or 'deleted' state.
If a student has a passing grade a request will made
for a new cert
If a student does not have a passing grade the status
will change to status.notpassing
Returns the student's status
"""
VALID_STATUSES = [status.unavailable, status.deleted, status.error,
status.notpassing]
cert_status = certificate_status_for_student(
student, course_id)['status']
if cert_status in VALID_STATUSES:
# grade the student
course = courses.get_course_by_id(course_id)
grade = grades.grade(student, self.request, course)
profile = UserProfile.objects.get(user=student)
cert, created = GeneratedCertificate.objects.get_or_create(
user=student, course_id=course_id)
if grade['grade'] is not None:
cert_status = status.generating
key = make_hashkey(random.random())
cert.status = cert_status
cert.grade = grade['percent']
cert.user = student
cert.course_id = course_id
cert.key = key
cert.name = profile.name
contents = {
'action': 'create',
'username': student.username,
'course_id': course_id,
'name': profile.name,
}
self._send_to_xqueue(contents, key)
cert.save()
else:
cert_status = status.notpassing
cert.grade = grade['percent']
cert.status = cert_status
cert.user = student
cert.course_id = course_id
cert.name = profile.name
cert.save()
return cert_status
def _send_to_xqueue(self, contents, key):
xheader = make_xheader(
'https://{0}/update_certificate?{1}'.format(
settings.SITE_NAME, key), key, settings.CERT_QUEUE)
(error, msg) = self.xqueue_interface.send_to_queue(
header=xheader, body=json.dumps(contents))
if error:
logger.critical('Unable to add a request to the queue')
raise Exception('Unable to send queue message')