from datetime import datetime
+import os.path
-from django.db import models
from django.contrib.auth.models import User
-from django.utils.translation import ugettext_lazy as _
+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 string_concat, ugettext_lazy as _
from mercurial import mdiff, simplemerge
-import pickle
+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
- """
+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)
_object_cache = {}
class Meta:
+ abstract = True
ordering = ['ordering']
def __unicode__(self):
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 contains a pickled diff needed to reproduce the initial document.
+ Data file contains a gzipped text of the document.
"""
- author = models.ForeignKey(User, null=True, blank=True)
- author_desc = models.CharField(max_length=128, null=True, blank=True)
- patch = models.TextField(blank=True)
- tree = models.ForeignKey('Document')
- revision = models.IntegerField(db_index=True)
+ 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(blank=True, default='')
+ description = models.TextField(_('description'), blank=True, default='')
created_at = models.DateTimeField(editable=False, db_index=True,
default=datetime.now)
- publishable = models.BooleanField(default=False)
-
- tags = models.ManyToManyField(Tag)
+ publishable = models.BooleanField(_('publishable'), default=False)
class Meta:
+ abstract = True
ordering = ('created_at',)
unique_together = ['tree', 'revision']
def __unicode__(self):
- return u"Id: %r, Tree %r, Parent %r, Patch '''\n%s'''" % (self.id, self.tree_id, self.parent_id, self.patch)
+ 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:
self.author.last_name,
self.author.email)
else:
- return self.author_desc
+ 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:
- self.revision = self.tree.revision() + 1
+ 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)
- @staticmethod
- def make_patch(src, dst):
- if isinstance(src, unicode):
- src = src.encode('utf-8')
- if isinstance(dst, unicode):
- dst = dst.encode('utf-8')
- return pickle.dumps(mdiff.textdiff(src, dst))
-
def materialize(self):
- # special care for merged nodes
- if self.parent is None and self.merge_parent is not None:
- return self.apply_to(self.merge_parent.materialize())
-
- changes = Change.objects.exclude(parent=None).filter(
- tree=self.tree,
- revision__lte=self.revision).order_by('revision')
- text = u''
- for change in changes:
- text = change.apply_to(text)
- return text
-
- def make_child(self, patch, description, author=None,
- author_desc=None, tags=None):
- ch = self.children.create(patch=patch,
- tree=self.tree, author=author,
- author_desc=author_desc,
- description=description)
- if tags is not None:
- ch.tags = tags
- return ch
-
- def make_merge_child(self, patch, description, author=None,
- author_desc=None, tags=None):
- ch = self.merge_children.create(patch=patch,
- tree=self.tree, author=author,
- author_desc=author_desc,
- description=description,
- tags=tags)
- if tags is not None:
- ch.tags = tags
- return ch
-
- def apply_to(self, text):
- return mdiff.patch(text, pickle.loads(self.patch.encode('ascii')))
-
- def merge_with(self, other, author=None, author_desc=None,
+ 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
+ # immediate child - fast forward
return other
- local = self.materialize()
- base = other.merge_parent.materialize()
- remote = other.apply_to(base)
+ 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())
- patch = self.make_patch(local, result)
- return self.children.create(
- patch=patch, merge_parent=other, tree=self.tree,
- author=author, author_desc=author_desc,
+ 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)
-class Document(models.Model):
- """
- File in repository.
- """
- creator = models.ForeignKey(User, null=True, blank=True, editable=False)
- head = models.ForeignKey(Change,
+
+
+
+def create_tag_model(model):
+ name = model.__name__ + 'Tag'
+
+ class Meta(Tag.Meta):
+ app_label = model._meta.app_label
+ verbose_name = string_concat(_("tag"), " ", _("for:"), " ",
+ model._meta.verbose_name)
+ verbose_name_plural = string_concat(_("tags"), " ", _("for:"), " ",
+ model._meta.verbose_name)
+
+ 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
+ verbose_name = string_concat(_("change"), " ", _("for:"), " ",
+ model._meta.verbose_name)
+ verbose_name_plural = string_concat(_("changes"), " ", _("for:"), " ",
+ model._meta.verbose_name)
+
+ 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)
+ 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)
- @models.permalink
- def get_absolute_url(self):
- return ('dvcs.views.document_data', (), {
- 'document_id': self.id,
- 'version': self.head_id,
- })
-
def materialize(self, change=None):
if self.head is None:
return u''
change = self.change_set.get(pk=change)
return change.materialize()
- def commit(self, **kwargs):
+ 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 not isinstance(parent, Change):
- parent = Change.objects.get(pk=kwargs['parent'])
-
- if 'patch' not in kwargs:
- if 'text' not in kwargs:
- raise ValueError("You must provide either patch or target document.")
- patch = Change.make_patch(self.materialize(change=parent), kwargs['text'])
- else:
- if 'text' in kwargs:
- raise ValueError("You can provide only text or patch - not both")
- patch = kwargs['patch']
+ if parent is not None and not isinstance(parent, Change):
+ parent = self.change_set.objects.get(pk=kwargs['parent'])
- author = kwargs.get('author', None)
- author_desc = kwargs.get('author_desc', None)
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()
- old_head = self.head
- if parent != old_head:
- change = parent.make_merge_child(patch, author=author,
- author_desc=author_desc,
+ change = self.change_set.create(author=author,
+ author_name=author_name,
+ author_email=author_email,
description=kwargs.get('description', ''),
- tags=tags)
- # not Fast-Forward - perform a merge
- self.head = old_head.merge_with(change, author=author,
- author_desc=author_desc)
+ 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 = parent.make_child(patch, author=author,
- author_desc=author_desc,
- description=kwargs.get('description', ''),
- tags=tags)
-
+ 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)
+ return self.change_set.all().order_by('revision')
def revision(self):
rev = self.change_set.aggregate(
models.Max('revision'))['revision__max']
- return rev if rev is not None else -1
+ return rev
def at_revision(self, rev):
- if rev is not None:
- return self.change_set.get(revision=rev)
- else:
- return self.head
+ """Returns a Change with given revision number."""
+ return self.change_set.get(revision=rev)
def publishable(self):
- changes = self.change_set.filter(publishable=True).order_by('-created_at')[:1]
- if changes.count():
- return changes[0]
+ changes = self.history().filter(publishable=True)
+ if changes.exists():
+ return changes.order_by('-revision')[0]
else:
return None
- @staticmethod
- def listener_initial_commit(sender, instance, created, **kwargs):
- # run for Document and its subclasses
- if not isinstance(instance, Document):
- return
- if created:
- instance.head = Change.objects.create(
- revision=-1,
- author=instance.creator,
- patch=Change.make_patch('', ''),
- tree=instance)
- instance.save()
-
-models.signals.post_save.connect(Document.listener_initial_commit)
+ @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()
+ # workaround for a non-atomic UPDATE in SQLITE
+ self.change_set.all().update(revision=0-models.F('revision'))
+ self.change_set.all().update(revision=other_revs - models.F('revision'))
+ other.change_set.all().update(tree=self)
+ assert not other.change_set.exists()
+ other.delete()