-from datetime import datetime
-import os.path
-
-from django.contrib.auth.models import User
-from django.core.files.base import ContentFile
-from django.core.files.storage import FileSystemStorage
-from django.db import models, transaction
-from django.db.models.base import ModelBase
-from django.utils.translation import ugettext_lazy as _
-from mercurial import mdiff, simplemerge
-
-from django.conf import settings
-from dvcs.signals import post_commit, post_publishable
-from dvcs.storage import GzipFileSystemStorage
-
-
-class Tag(models.Model):
- """A tag (e.g. document stage) which can be applied to a Change."""
- name = models.CharField(_('name'), max_length=64)
- slug = models.SlugField(_('slug'), unique=True, max_length=64,
- null=True, blank=True)
- ordering = models.IntegerField(_('ordering'))
-
- _object_cache = {}
-
- class Meta:
- abstract = True
- ordering = ['ordering']
- verbose_name = _("tag")
- verbose_name_plural = _("tags")
-
- def __unicode__(self):
- return self.name
-
- @classmethod
- def get(cls, slug):
- if slug in cls._object_cache:
- return cls._object_cache[slug]
- else:
- obj = cls.objects.get(slug=slug)
- cls._object_cache[slug] = obj
- return obj
-
- @staticmethod
- def listener_changed(sender, instance, **kwargs):
- sender._object_cache = {}
-
- def next(self):
- """
- Returns the next tag - stage to work on.
- Returns None for the last stage.
- """
- try:
- return type(self).objects.filter(ordering__gt=self.ordering)[0]
- except IndexError:
- return None
-
-models.signals.pre_save.connect(Tag.listener_changed, sender=Tag)
-
-
-def data_upload_to(instance, filename):
- return "%d/%d" % (instance.tree.pk, instance.pk)
-
-class Change(models.Model):
- """
- Single document change related to previous change. The "parent"
- argument points to the version against which this change has been
- recorded. Initial text will have a null parent.
-
- Data file contains a gzipped text of the document.
- """
- author = models.ForeignKey(User, null=True, blank=True, verbose_name=_('author'))
- author_name = models.CharField(_('author name'), max_length=128,
- null=True, blank=True,
- help_text=_("Used if author is not set.")
- )
- author_email = models.CharField(_('author email'), max_length=128,
- null=True, blank=True,
- help_text=_("Used if author is not set.")
- )
- revision = models.IntegerField(_('revision'), db_index=True)
-
- parent = models.ForeignKey('self',
- null=True, blank=True, default=None,
- verbose_name=_('parent'),
- related_name="children")
-
- merge_parent = models.ForeignKey('self',
- null=True, blank=True, default=None,
- verbose_name=_('merge parent'),
- related_name="merge_children")
-
- description = models.TextField(_('description'), blank=True, default='')
- created_at = models.DateTimeField(editable=False, db_index=True,
- default=datetime.now)
- publishable = models.BooleanField(_('publishable'), default=False)
-
- class Meta:
- abstract = True
- ordering = ('created_at',)
- unique_together = ['tree', 'revision']
- verbose_name = _("change")
- verbose_name_plural = _("changes")
-
- def __unicode__(self):
- return u"Id: %r, Tree %r, Parent %r, Data: %s" % (self.id, self.tree_id, self.parent_id, self.data)
-
- def author_str(self):
- if self.author:
- return "%s %s <%s>" % (
- self.author.first_name,
- self.author.last_name,
- self.author.email)
- else:
- return "%s <%s>" % (
- self.author_name,
- self.author_email
- )
-
-
- def save(self, *args, **kwargs):
- """
- take the next available revision number if none yet
- """
- if self.revision is None:
- tree_rev = self.tree.revision()
- if tree_rev is None:
- self.revision = 1
- else:
- self.revision = tree_rev + 1
- return super(Change, self).save(*args, **kwargs)
-
- def materialize(self):
- f = self.data.storage.open(self.data)
- text = f.read()
- f.close()
- return unicode(text, 'utf-8')
-
- def merge_with(self, other, author=None,
- author_name=None, author_email=None,
- description=u"Automatic merge."):
- """Performs an automatic merge after straying commits."""
- assert self.tree_id == other.tree_id # same tree
- if other.parent_id == self.pk:
- # immediate child - fast forward
- return other
-
- local = self.materialize().encode('utf-8')
- base = other.parent.materialize().encode('utf-8')
- remote = other.materialize().encode('utf-8')
-
- merge = simplemerge.Merge3Text(base, local, remote)
- result = ''.join(merge.merge_lines())
- merge_node = self.children.create(
- merge_parent=other, tree=self.tree,
- author=author,
- author_name=author_name,
- author_email=author_email,
- description=description)
- merge_node.data.save('', ContentFile(result))
- return merge_node
-
- def revert(self, **kwargs):
- """ commit this version of a doc as new head """
- self.tree.commit(text=self.materialize(), **kwargs)
-
- def set_publishable(self, publishable):
- self.publishable = publishable
- self.save()
- post_publishable.send(sender=self, publishable=publishable)
-
-
-def create_tag_model(model):
- name = model.__name__ + 'Tag'
-
- class Meta(Tag.Meta):
- app_label = model._meta.app_label
-
- attrs = {
- '__module__': model.__module__,
- 'Meta': Meta,
- }
- return type(name, (Tag,), attrs)
-
-
-def create_change_model(model):
- name = model.__name__ + 'Change'
- repo = GzipFileSystemStorage(location=model.REPO_PATH)
-
- class Meta(Change.Meta):
- app_label = model._meta.app_label
-
- attrs = {
- '__module__': model.__module__,
- 'tree': models.ForeignKey(model, related_name='change_set', verbose_name=_('document')),
- 'tags': models.ManyToManyField(model.tag_model, verbose_name=_('tags'), related_name='change_set'),
- 'data': models.FileField(_('data'), upload_to=data_upload_to, storage=repo),
- 'Meta': Meta,
- }
- return type(name, (Change,), attrs)
-
-
-class DocumentMeta(ModelBase):
- "Metaclass for Document models."
- def __new__(cls, name, bases, attrs):
-
- model = super(DocumentMeta, cls).__new__(cls, name, bases, attrs)
- if not model._meta.abstract:
- # create a real Tag object and `stage' fk
- model.tag_model = create_tag_model(model)
- models.ForeignKey(model.tag_model, verbose_name=_('stage'),
- null=True, blank=True).contribute_to_class(model, 'stage')
-
- # create real Change model and `head' fk
- model.change_model = create_change_model(model)
-
- models.ForeignKey(model.change_model,
- null=True, blank=True, default=None,
- verbose_name=_('head'),
- help_text=_("This document's current head."),
- editable=False).contribute_to_class(model, 'head')
-
- models.ForeignKey(User, null=True, blank=True, editable=False,
- verbose_name=_('creator'), related_name="created_%s" % name.lower()
- ).contribute_to_class(model, 'creator')
-
- return model
-
-
-class Document(models.Model):
- """File in repository. Subclass it to use version control in your app."""
-
- __metaclass__ = DocumentMeta
-
- # default repository path
- REPO_PATH = os.path.join(settings.MEDIA_ROOT, 'dvcs')
-
- user = models.ForeignKey(User, null=True, blank=True,
- verbose_name=_('user'), help_text=_('Work assignment.'))
-
- class Meta:
- abstract = True
-
- def __unicode__(self):
- return u"{0}, HEAD: {1}".format(self.id, self.head_id)
-
- def materialize(self, change=None):
- if self.head is None:
- return u''
- if change is None:
- change = self.head
- elif not isinstance(change, Change):
- change = self.change_set.get(pk=change)
- return change.materialize()
-
- def commit(self, text, author=None, author_name=None, author_email=None,
- publishable=False, **kwargs):
- """Commits a new revision.
-
- This will automatically merge the commit into the main branch,
- if parent is not document's head.
-
- :param unicode text: new version of the document
- :param parent: parent revision (head, if not specified)
- :type parent: Change or None
- :param User author: the commiter
- :param unicode author_name: commiter name (if ``author`` not specified)
- :param unicode author_email: commiter e-mail (if ``author`` not specified)
- :param Tag[] tags: list of tags to apply to the new commit
- :param bool publishable: set new commit as ready to publish
- :returns: new head
- """
- if 'parent' not in kwargs:
- parent = self.head
- else:
- parent = kwargs['parent']
- if parent is not None and not isinstance(parent, Change):
- parent = self.change_set.objects.get(pk=kwargs['parent'])
-
- tags = kwargs.get('tags', [])
- if tags:
- # set stage to next tag after the commited one
- self.stage = max(tags, key=lambda t: t.ordering).next()
-
- change = self.change_set.create(author=author,
- author_name=author_name,
- author_email=author_email,
- description=kwargs.get('description', ''),
- publishable=publishable,
- parent=parent)
-
- change.tags = tags
- change.data.save('', ContentFile(text.encode('utf-8')))
- change.save()
-
- if self.head:
- # merge new change as new head
- self.head = self.head.merge_with(change, author=author,
- author_name=author_name,
- author_email=author_email)
- else:
- self.head = change
- self.save()
-
- post_commit.send(sender=self.head)
-
- return self.head
-
- def history(self):
- return self.change_set.filter(revision__gt=-1)
-
- def revision(self):
- rev = self.change_set.aggregate(
- models.Max('revision'))['revision__max']
- return rev
-
- def at_revision(self, rev):
- """Returns a Change with given revision number."""
- return self.change_set.get(revision=rev)
-
- def publishable(self):
- changes = self.change_set.filter(publishable=True)
- if changes.exists():
- return changes.order_by('-created_at')[0]
- else:
- return None
-
- @transaction.commit_on_success
- def prepend_history(self, other):
- """Takes over the the other document's history and prepends to own."""
-
- assert self != other
- other_revs = other.change_set.all().count()
- self.change_set.all().update(revision=models.F('revision') + other_revs)
- other.change_set.all().update(tree=self)
- assert not other.change_set.exists()
- other.delete()