simplify dvcs storage

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

diff --git a/apps/dvcs/models.py b/apps/dvcs/models.py
index dddbf3a..1668dee 100644 (file)
--- a/apps/dvcs/models.py
+++ b/apps/dvcs/models.py
@@ -1,10 +1,15 @@
 from datetime import datetime
 
 from datetime import datetime
 

+from django.core.files.base import ContentFile
+from django.core.files.storage import FileSystemStorage

 from django.db import models
 from django.db import models

+from django.db.models.base import ModelBase

 from django.contrib.auth.models import User
 from django.utils.translation import ugettext_lazy as _
 from mercurial import mdiff, simplemerge
 from django.contrib.auth.models import User
 from django.utils.translation import ugettext_lazy as _
 from mercurial import mdiff, simplemerge

-import pickle
+
+from dvcs.fields import GzipFileSystemStorage
+from dvcs.settings import REPO_PATH

 
 
 class Tag(models.Model):
 
 
 class Tag(models.Model):


@@ -20,6 +25,7 @@ class Tag(models.Model):
     _object_cache = {}
 
     class Meta:
     _object_cache = {}
 
     class Meta:

+        abstract = True

         ordering = ['ordering']
 
     def __unicode__(self):
         ordering = ['ordering']
 
     def __unicode__(self):


@@ -38,21 +44,36 @@ class Tag(models.Model):
     def listener_changed(sender, instance, **kwargs):
         sender._object_cache = {}
 
     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 Tag.objects.filter(ordering__gt=self.ordering)[0]
+        except IndexError:
+            return None
+

 models.signals.pre_save.connect(Tag.listener_changed, sender=Tag)
 
 
 models.signals.pre_save.connect(Tag.listener_changed, sender=Tag)
 
 

+repo = GzipFileSystemStorage(location=REPO_PATH)
+
+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.
         
 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 = 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')
+    author_name = models.CharField(max_length=128, null=True, blank=True)
+    author_email = models.CharField(max_length=128, null=True, blank=True)
+    data = models.FileField(upload_to=data_upload_to, storage=repo)

     revision = models.IntegerField(db_index=True)
 
     parent = models.ForeignKey('self',
     revision = models.IntegerField(db_index=True)
 
     parent = models.ForeignKey('self',


@@ -66,15 +87,15 @@ class Change(models.Model):
     description = models.TextField(blank=True, default='')
     created_at = models.DateTimeField(editable=False, db_index=True, 
                         default=datetime.now)
     description = models.TextField(blank=True, default='')
     created_at = models.DateTimeField(editable=False, db_index=True, 
                         default=datetime.now)

-
-    tags = models.ManyToManyField(Tag)
+    publishable = models.BooleanField(default=False)

 
     class Meta:
 
     class Meta:

+        abstract = True

         ordering = ('created_at',)
         unique_together = ['tree', 'revision']
 
     def __unicode__(self):
         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:
 
     def author_str(self):
         if self.author:


@@ -83,7 +104,10 @@ class Change(models.Model):
                 self.author.last_name, 
                 self.author.email)
         else:
                 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):
 
 
     def save(self, *args, **kwargs):


@@ -91,87 +115,102 @@ class Change(models.Model):
             take the next available revision number if none yet
         """
         if self.revision is None:
             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 = 0
+            else:
+                self.revision = tree_rev + 1

         return super(Change, self).save(*args, **kwargs)
 
         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):
     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."):
             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, 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)
                     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 create_tag_model(model):
+    name = model.__name__ + 'Tag'
+    attrs = {
+        '__module__': model.__module__,
+    }
+    return type(name, (Tag,), attrs)
+
+
+def create_change_model(model):
+    name = model.__name__ + 'Change'
+
+    attrs = {
+        '__module__': model.__module__,
+        'tree': models.ForeignKey(model, related_name='change_set'),
+        'tags': models.ManyToManyField(model.tag_model, related_name='change_set'),
+    }
+    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, 
+                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,
+                    help_text=_("This document's current head."),
+                    editable=False).contribute_to_class(model, 'head')
+
+        return model
+
+
+

 class Document(models.Model):
     """
         File in repository.        
     """
 class Document(models.Model):
     """
         File in repository.        
     """

-    creator = models.ForeignKey(User, null=True, blank=True, editable=False)
-    head = models.ForeignKey(Change,
-                    null=True, blank=True, default=None,
-                    help_text=_("This document's current head."),
-                    editable=False)
+    __metaclass__ = DocumentMeta
+
+    creator = models.ForeignKey(User, null=True, blank=True, editable=False,
+                related_name="created_documents")
+
+    user = models.ForeignKey(User, null=True, blank=True)
+
+    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)


@@ -192,42 +231,39 @@ 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, **kwargs):

         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 '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 = kwargs.get('author', None)

-        author_desc = kwargs.get('author_desc', None)
+        author_name = kwargs.get('author_name', None)
+        author_email = kwargs.get('author_email', None)

         tags = kwargs.get('tags', [])
         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', ''),
                     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)
-        else:
-            self.head = parent.make_child(patch, author=author, 
-                    author_desc=author_desc, 
-                    description=kwargs.get('description', ''),
-                    tags=tags)
+                    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()
         return self.head
 
         self.save()
         return self.head
 


@@ -237,32 +273,15 @@ class Document(models.Model):
     def revision(self):
         rev = self.change_set.aggregate(
                 models.Max('revision'))['revision__max']
     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):
 
     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 last_tagged(self, tag):
-        changes = tag.change_set.filter(tree=self).order_by('-created_at')[:1]
+    def publishable(self):
+        changes = self.change_set.filter(publishable=True).order_by('-created_at')[:1]

         if changes.count():
             return changes[0]
         else:
             return None
         if changes.count():
             return changes[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)