Fixes #1598

[redakcja.git] / apps / dvcs / models.py

diff --git a/apps/dvcs/models.py b/apps/dvcs/models.py
index 1c30387..f4cb519 100644 (file)
--- a/apps/dvcs/models.py
+++ b/apps/dvcs/models.py
@@ -1,8 +1,65 @@
-from django.db import models
+from datetime import datetime
+import os.path
+

 from django.contrib.auth.models import User
 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.utils.translation import 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."""
+    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 get_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):
     """
 
 class Change(models.Model):
     """


@@ -10,114 +67,183 @@ class Change(models.Model):
         argument points to the version against which this change has been 
         recorded. Initial text will have a null 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)
-    patch = models.TextField(blank=True)
-    tree = models.ForeignKey('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,
 
     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,
                         related_name="children")
 
     merge_parent = models.ForeignKey('self',
                         null=True, blank=True, default=None,

+                        verbose_name=_('merge parent'),

                         related_name="merge_children")
 
                         related_name="merge_children")
 

-    description = models.TextField(blank=True, default='')
-    created_at = models.DateTimeField(auto_now_add=True)
+    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:
 
     class Meta:

+        abstract = True

         ordering = ('created_at',)
         ordering = ('created_at',)

+        unique_together = ['tree', 'revision']
+        verbose_name = _("change")
+        verbose_name_plural = _("changes")

 
     def __unicode__(self):
 
     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)

 
 

-    @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 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):
 
     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.filter(
-                        ~models.Q(parent=None) | models.Q(merge_parent=None),
-                        tree=self.tree,
-                        created_at__lte=self.created_at).order_by('created_at')
-        text = u''
-        for change in changes:
-            text = change.apply_to(text)
-        return text
-
-    def make_child(self, patch, author, description):
-        return self.children.create(patch=patch,
-                        tree=self.tree, author=author,
-                        description=description)
-
-    def make_merge_child(self, patch, author, description):
-        return self.merge_children.create(patch=patch,
-                        tree=self.tree, author=author,
-                        description=description)
-
-    def apply_to(self, text):
-        return mdiff.patch(text, pickle.loads(self.patch.encode('ascii')))
-
-    def merge_with(self, other, author, description=u"Automatic merge."):
+        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:
         assert self.tree_id == other.tree_id  # same tree
         if other.parent_id == self.pk:

-            # immediate child 
+            # immediate child - fast forward

             return other
 
             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())
 
         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, description=description)
+        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 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)
-    head = models.ForeignKey(Change,
+
+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,
                     null=True, blank=True, default=None,

-                    help_text=_("This document's current head."))
+                    verbose_name=_('head'), 
+                    help_text=_("This document's current head."),
+                    editable=False).contribute_to_class(model, 'head')

 
 

-    @classmethod
-    def create(cls, text='', *args, **kwargs):
-        instance = cls(*args, **kwargs)
-        instance.save()
-        head = instance.head
-        head.patch = Change.make_patch('', text)
-        head.save()
-        return instance
+            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 __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''
     def materialize(self, change=None):
         if self.head is None:
             return u''


@@ -127,53 +253,87 @@ class Document(models.Model):
             change = self.change_set.get(pk=change)
         return change.materialize()
 
             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 'parent' not in kwargs:
             parent = self.head
         else:
             parent = kwargs['parent']

-            if not isinstance(parent, Change):
-                parent = Change.objects.get(pk=kwargs['parent'])
+            if parent is not None and not isinstance(parent, Change):
+                parent = self.change_set.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']
-
-        old_head = self.head
-        if parent != old_head:
-            change = parent.make_merge_child(patch, kwargs['author'], kwargs.get('description', ''))
-            # not Fast-Forward - perform a merge
-            self.head = old_head.merge_with(change, author=kwargs['author'])
-        else:
-            self.head = parent.make_child(patch, kwargs['author'], kwargs.get('description', ''))
+        tags = kwargs.get('tags', [])
+        if tags:
+            # set stage to next tag after the commited one
+            self.stage = max(tags, key=lambda t: t.ordering).get_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()
         self.save()

+
+        post_commit.send(sender=self.head)
+

         return self.head
 
     def history(self):
         return self.head
 
     def history(self):

-        return self.change_set.all()
+        return self.change_set.all().order_by('revision')

 
     def revision(self):
 
     def revision(self):

-        return self.change_set.all().count()
+        rev = self.change_set.aggregate(
+                models.Max('revision'))['revision__max']
+        return rev

 
     def at_revision(self, rev):
 
     def at_revision(self, rev):

-        if rev:
-            return self.change_set.all()[rev-1]
+        """Returns a Change with given revision number."""
+        return self.change_set.get(revision=rev)
+
+    def publishable(self):
+        changes = self.history().filter(publishable=True)
+        if changes.exists():
+            return changes.order_by('-revision')[0]

         else:
         else:

-            return self.head
+            return None

 
 

-    @staticmethod
-    def listener_initial_commit(sender, instance, created, **kwargs):
-        if created:
-            instance.head = Change.objects.create(
-                    author=instance.creator,
-                    patch=Change.make_patch('', ''),
-                    tree=instance)
-            instance.save()
-
-models.signals.post_save.connect(Document.listener_initial_commit, sender=Document)
+    @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()