# pylint: disable=unused-argument, no-self-use, avoid-list-comprehension
import difflib
from django.db.models import signals
from django.http import HttpResponseRedirect
from django.template.defaultfilters import safe
from django.utils.translation import gettext_lazy as _
from simple_history.admin import SimpleHistoryAdmin
from simple_history.models import HistoricalRecords
from tcms.core.templatetags.extra_filters import bleach_input
[docs]
def diff_objects(old_instance, new_instance, fields):
"""
Diff two objects by examining the given fields and
return a string.
"""
full_diff = []
for field in fields:
field_diff = []
old_value = getattr(old_instance, field.attname)
new_value = getattr(new_instance, field.attname)
# clean stored XSS
if isinstance(old_value, str):
old_value = bleach_input(old_value)
if isinstance(new_value, str):
new_value = bleach_input(new_value)
for line in difflib.unified_diff(
str(old_value).split("\n"),
str(new_value).split("\n"),
fromfile=field.attname,
tofile=field.attname,
lineterm="",
):
field_diff.append(line)
full_diff.extend(field_diff)
return "\n".join(full_diff)
[docs]
def history_email_for(instance, title):
"""
Generate the subject and email body that is sent via
email notifications post update!
"""
history = instance.history.latest()
subject = _("UPDATE: %(model_name)s #%(pk)d - %(title)s") % {
"model_name": instance.__class__.__name__,
"pk": instance.pk,
"title": title,
}
body = (
_(
"""Updated on %(history_date)s
Updated by %(username)s
%(diff)s
For more information:
%(instance_url)s"""
)
% {
"history_date": history.history_date.strftime("%c"),
"username": getattr(history.history_user, "username", ""),
"diff": history.history_change_reason,
"instance_url": instance.get_full_url(),
}
)
return subject, body
[docs]
class KiwiHistoricalRecords(HistoricalRecords):
"""
This class will keep track of what fields were changed
inside of the ``history_change_reason`` field. This gives us
a crude changelog until upstream introduces their new interface.
"""
[docs]
def pre_save(self, instance, **kwargs):
"""
Signal handlers don't have access to the previous version of
an object so we have to load it from the database!
"""
if kwargs.get("raw", False):
return
if instance.pk and hasattr(instance, "history"):
instance.previous = instance.__class__.objects.filter(
pk=instance.pk
).first()
[docs]
def post_save(self, instance, created, using=None, **kwargs):
"""
Calculate the changelog and call the inherited method to
write the data into the database.
"""
if kwargs.get("raw", False):
return
if hasattr(instance, "previous") and instance.previous:
# note: simple_history.utils.update_change_reason() performs an extra
# DB query so it is better to use the private field instead!
# In older simple_history version this field wasn't private but was renamed
# in 2.10.0 hence the pylint disable!
instance._change_reason = diff_objects( # pylint: disable=protected-access
instance.previous, instance, self.fields_included(instance)
)
super().post_save(instance, created, using, **kwargs)
[docs]
def finalize(self, sender, **kwargs):
"""
Connect the pre_save signal handler after calling the inherited method.
"""
super().finalize(sender, **kwargs)
signals.pre_save.connect(self.pre_save, sender=sender, weak=False)
[docs]
class ReadOnlyHistoryAdmin(SimpleHistoryAdmin):
"""
Custom history admin which shows all fields
as read-only.
"""
history_list_display = ["Diff"]
[docs]
def Diff(self, obj): # pylint: disable=invalid-name
return safe(f"<pre>{obj.history_change_reason}</pre>")
[docs]
def get_readonly_fields(self, request, obj=None):
# make all fields readonly
readonly_fields = list(
set(
[field.name for field in self.opts.local_fields]
+ [field.name for field in self.opts.local_many_to_many]
)
)
return readonly_fields
[docs]
def response_change(self, request, obj):
super().response_change(request, obj)
return HttpResponseRedirect(obj.get_absolute_url())