class Subject(CreatedModified):
'''
This class represents a master patient index for the eHB system. It serves as the
primary key for linking a given subject stored in the eHB to all other records stored in
external systems
'''
first_name = EncryptCharField(max_length=50, verbose_name='First Name')
last_name = EncryptCharField(max_length=70, verbose_name='Last Name')
# This is the organization that created the subject record, e.g. CHOP
organization = models.ForeignKey(Organization, on_delete=models.CASCADE)
# This is the organization's id for this subject, e.g. MRN value
organization_subject_id = EncryptCharField(max_length=120, verbose_name='Organization Subject Record ID')
dob = EncryptDateField(verbose_name='Date Of Birth', help_text=date_help_text)
cleanmsg = 'There is already a Subject for this Organization and Subject ID'
class Meta(CreatedModified.Meta):
ordering = ['organization', 'organization_subject_id']
# class Meta(CreatedModified.Meta):
# unique_together=('organization','organization_subject_id')
# I WOULD LIKE TO USE THE META ABOVE BUT RIGHT NOW THAT BREAKS THE ehb-client WHEN TRYING UPDATE AN EXTERNAL_RECORD
def clean(self):
try:
subs = Subject.objects.filter(
organization_subject_id=self.organization_subject_id).filter(
organization=self.organization)
for sub in subs:
if sub.pk != self.pk: # if they are equal then we are modifying this record
raise ValidationError(self.cleanmsg)
except Organization.DoesNotExist:
pass # The Organization field validation will handle this
def responseFieldDict(self):
response = {}
response['created'] = self.created.strftime('%Y-%m-%d %H:%M:%S.%f')
response['modified'] = self.modified.strftime('%Y-%m-%d %H:%M:%S.%f')
response['first_name'] = self.first_name
response['last_name'] = self.last_name
response['organization'] = self.organization_id
response['id'] = self.id
response['organization_subject_id'] = self.organization_subject_id
response['organization_id_label'] = self.organization.subject_id_label
response['dob'] = self.dob.strftime('%Y-%m-%d')
return response
def __str__(self):
return "{0}, {1} : {2} : {3}".format(
self.last_name,
self.first_name,
self.organization.name,
self.organization_subject_id
)
class GroupEhbKey(GroupPropsKey):
key = EncryptCharField(max_length=255,
unique=True,
verbose_name='EHB KEY',
editable=False,
blank=True)
def _make_random_key(self,
seed,
ja,
l,
chars=string.ascii_uppercase + string.digits):
random.seed(seed)
for i in range(ja):
dummy = random.random()
return ''.join(random.choice(chars) for idx in range(l))
def _set_key(self):
'''Generate a unique key'''
if not self.pk:
ehb_key_length = self._ehb_key_length()
seed = self._ehb_key_seed()
jump = GroupEhbKey.objects.count()
# Generate a new key, overriding any key that was used to create this object
uk = ''
idx = 0
max_idx = 1e6
while idx < max_idx:
uk = self._make_random_key(seed=seed,
ja=jump + idx,
l=ehb_key_length)
if not GroupEhbKey.objects.all():
idx = max_idx
else:
grps_using_uk = GroupEhbKey.objects.filter(key=uk)
if grps_using_uk.count() == 0:
idx = max_idx
else:
idx += 1
self.key = uk
def _ehb_key_seed(self, default=123456789):
return self.ehb_prop('EHB_GROUP_EHB_KEYS', 'seed', default)
def _ehb_key_length(self, default=15):
return self.ehb_prop('EHB_GROUP_EHB_KEYS', 'length', default)
def save(self, force_insert=False, force_update=False, using=None):
self._set_key()
super(GroupEhbKey, self).save()
def __str__(self):
return self.key
class UserAudit(CreatedModified):
"""
This class will store User Audit data to track subject data changes.
"""
id = models.AutoField(primary_key=True)
user_name = models.CharField(
max_length=50, verbose_name='User Name')
# Change type: SubjectFamRelation, external record, Subject ... should reference a table
change_type = models.CharField(
max_length=50, verbose_name='Change type')
# is not a foreignKey because this could be a PK for many different tables
change_type_ehb_pk = models.CharField(
max_length=20, verbose_name='Change Type eHB PK', blank=True)
# Change Action: create, delete or update
change_action = models.CharField(
max_length=50, verbose_name='Change action', blank=True)
# Change Field: updated field
change_field = models.CharField(
max_length=50, verbose_name='Change field', blank=True)
old_value = EncryptCharField(
max_length=128, verbose_name='Old Value', blank=True)
new_value = EncryptCharField(
max_length=128, verbose_name='New value', blank=True)
subject = models.ForeignKey(Subject, verbose_name='Subject', on_delete=models.CASCADE)
class Group(CreatedModified):
'''
This class is used as a unique identifier to group related model objects
such as Subjects and External Records.
The ehb_key field is randomly generated by the eHB and is guaranteed to be
unique. Values for ehb_key submitted to
the API or in a form are ignored.
'''
name = EncryptCharField(max_length=255, unique=True, verbose_name='Group Name')
client_key = models.CharField(max_length=255, verbose_name='Client KEY', editable=True)
is_locking = models.BooleanField(default=False, verbose_name='Lock Group')
# this cannot use onetoone because I don't want the ehb_keys to EVER be deleted
ehb_key = models.ForeignKey(GroupEhbKey, editable=False, blank=True, unique=True, on_delete=models.CASCADE)
desc_help = 'Please briefly describe this Group.'
description = models.TextField(verbose_name='Group Description', help_text=desc_help)
def _create_ehb_key(self):
'''generate an ehb_key for this Group'''
# if the key already exists then this model is being edited but this key should not change
try:
if self.ehb_key:
return
except Exception:
group_ehb_key = GroupEhbKey()
group_ehb_key.save()
self.ehb_key = group_ehb_key
def ehb_prop(self, GROUP, KEY, default=None):
EHB_PROPS = settings.EHB_PROPS
if EHB_PROPS:
GROUP_SETTINGS = EHB_PROPS.get(GROUP)
if GROUP_SETTINGS:
return GROUP_SETTINGS.get(KEY, default)
def _salt_length(self, default=12):
return self.ehb_prop('EHB_GROUP_CLIENT_KEYS', 'salt_length', default)
def _salt_seed(self, default=987654321):
return self.ehb_prop('EHB_GROUP_CLIENT_KEYS', 'seed', default)
def _make_salt(self, jump):
salt_length = self._salt_length()
seed = self._salt_seed()
chars = string.ascii_uppercase + string.digits
random.seed(seed)
for i in range(jump): dummy = random.random()
return ''.join(random.choice(chars) for idx in range(salt_length))
def _hash_value(self, value):
value = value.encode("utf8")
h = hashlib.sha256()
h.update(value)
return h.hexdigest()
def verify_client_key(self, other_key):
if not other_key:
return False
b, alg, salt, shpw = self.client_key.split('$')
return self._hash_value(salt + other_key) == shpw
def save(self, force_insert=False, force_update=False, using=None):
self._create_ehb_key()
jump = self.pk
if not jump:
jump = Group.objects.count()
salt = self._make_salt(jump=jump)
prefix = '$sha256$' + salt + '$'
if self.client_key and not self.client_key.startswith(prefix):
self.client_key = '$sha256$'+salt+'$'+self._hash_value(salt + self.client_key)
super(Group, self).save()
class Meta(CreatedModified.Meta):
ordering = ['name']
def __str__(self):
return self.name