import logging from functools import partial from django.db import models from django.db import transaction from rest_framework.exceptions import NotFound from django.contrib.auth import get_user_model from api.utils import dict_diff from api.exceptions import DryccException, AlreadyExists, UnprocessableEntity from .base import UuidAuditedModel User = get_user_model() logger = logging.getLogger(__name__) class AppSettings(UuidAuditedModel): """ Instance of Application settings used by scheduler """ owner = models.ForeignKey(User, on_delete=models.PROTECT) app = models.ForeignKey('App', on_delete=models.CASCADE) routable = models.BooleanField(default=None) autodeploy = models.BooleanField(default=None) autorollback = models.BooleanField(default=None) autoscale = models.JSONField(default=dict, blank=True) label = models.JSONField(default=dict, blank=True) class Meta: get_latest_by = 'created' unique_together = (('app', 'uuid'), ) ordering = ['-created'] def __init__(self, *args, **kwargs): UuidAuditedModel.__init__(self, *args, **kwargs) self.summary = [] def __str__(self): return "{}-{}".format(self.app.id, str(self.uuid)[:7]) def log(self, message, level=logging.INFO): """Logs a message in the context of this application. This prefixes log messages with an application "tag" that the customized drycc-logspout will be on the lookout for. When it's seen, the message-- usually an application event of some sort like releasing or scaling, will be considered as "belonging" to the application instead of the controller and will be handled accordingly. """ logger.log(level, "[{}]: {}".format(self.app.id, message)) def previous(self): """ Return the previous Release to this one. :return: the previous :class:`Release`, or None """ app_settings_set = self.app.appsettings_set if self.pk: app_settings_set = app_settings_set.exclude(pk=self.pk) try: # Get the Release previous to this one prev_app_settings = app_settings_set.latest() except AppSettings.DoesNotExist: prev_app_settings = None return prev_app_settings def _update_field(self, field, previous_settings): old = getattr(previous_settings, field, None) new = getattr(self, field, None) # if nothing changed copy the settings from previous if new is None and old is not None: setattr(self, field, old) elif new is None and isinstance(self._meta.get_field(field), models.BooleanField): setattr(self, field, True) elif old != new: self.summary += ["{} changed {} from {} to {}".format(self.owner, field, old, new)] def _update_autoscale(self, previous_settings): data = getattr(previous_settings, 'autoscale', {}).copy() new = getattr(self, 'autoscale', {}).copy() # If no previous settings then do nothing if not previous_settings: return # if nothing changed copy the settings from previous if not new and data: setattr(self, 'autoscale', data) elif data != new: for proc, scale in new.items(): if scale is None: # error if unsetting non-existing key if proc not in data: raise UnprocessableEntity('{} does not exist under {}'.format(proc, 'autoscale')) # noqa del data[proc] else: data[proc] = scale setattr(self, 'autoscale', data) # only apply new items for proc, scale in new.items(): self.app.autoscale(proc, scale) # if the autoscale information changed, log the dict diff changes = [] old_autoscale = getattr(previous_settings, 'autoscale', {}) diff = dict_diff(self.autoscale, old_autoscale) # try to be as succinct as possible added = ', '.join(list(map(lambda x: 'default' if x == '' else x, [k for k in diff.get('added', {})]))) # noqa added = 'added autoscale for process type ' + added if added else '' changed = ', '.join(list(map(lambda x: 'default' if x == '' else x, [k for k in diff.get('changed', {})]))) # noqa changed = 'changed autoscale for process type ' + changed if changed else '' deleted = ', '.join(list(map(lambda x: 'default' if x == '' else x, [k for k in diff.get('deleted', {})]))) # noqa deleted = 'deleted autoscale for process type ' + deleted if deleted else '' changes = ', '.join(i for i in (added, changed, deleted) if i) if changes: self.summary += ["{} {}".format(self.owner, changes)] def _update_label(self, previous_settings): data = getattr(previous_settings, 'label', {}).copy() new = getattr(self, 'label', {}).copy() if not previous_settings: return # if nothing changed copy the settings from previous if not new and data: setattr(self, 'label', data) elif data != new: for k, v in new.items(): if v is not None: data[k] = v else: if k not in data: raise UnprocessableEntity('{} does not exist under {}'.format(k, 'label')) # noqa del data[k] setattr(self, 'label', data) diff = dict_diff(self.label, getattr(previous_settings, 'label', {})) added = ', '.join(list(map(lambda x: 'default' if x == '' else x, [k for k in diff.get('added', {})]))) # noqa added = 'added label ' + added if added else '' changed = ', '.join(list(map(lambda x: 'default' if x == '' else x, [k for k in diff.get('changed', {})]))) # noqa changed = 'changed label ' + changed if changed else '' deleted = ', '.join(list(map(lambda x: 'default' if x == '' else x, [k for k in diff.get('deleted', {})]))) # noqa deleted = 'deleted label ' + deleted if deleted else '' changes = ', '.join(i for i in (added, changed, deleted) if i) if changes: if self.summary: self.summary += ' and ' self.summary += ["{} {}".format(self.owner, changes)] @transaction.atomic def save(self, ignore_update_fields=None, *args, **kwargs): previous_settings = None try: previous_settings = self.app.appsettings_set.latest() except AppSettings.DoesNotExist: pass update_fields = ["routable", "autodeploy", "autorollback", "autoscale", "label"] try: for field in update_fields: if ignore_update_fields is None or field not in ignore_update_fields: getattr( self, "_update_%s" % field, partial(self._update_field, field) )(previous_settings) except (UnprocessableEntity, NotFound): raise except Exception as e: self.delete() raise DryccException(str(e)) from e if not self.summary and previous_settings: self.delete() raise AlreadyExists("{} changed nothing".format(self.owner)) super(AppSettings, self).save(**kwargs) summary = ' '.join(self.summary) self.log('summary of app setting changes: {}'.format(summary), logging.DEBUG)