class Command(BaseCommand):
def handle(self, *apps, **options):
self.graph = MigrationLoader(None).graph
comment = options['comment']
self.picture = Digraph(comment=comment)
save_loc = options['filename']
self.render(save_loc)
def add_arguments(self, parser):
parser.add_argument('--comment',
help='optional comments/captions for the picture')
parser.add_argument('filename',
nargs='?',
help='a filename to write GraphViz contents to')
def _create_digraph(self):
nodes = sorted(self.graph.nodes.values(), key=self._get_tuple)
for node in nodes:
self._add_node(node)
for node in nodes:
self._add_dependencies(node)
@staticmethod
def _style_label(tupled_node):
return '/'.join(tupled_node)
@staticmethod
def _get_tuple(node):
return (node.app_label, node.name)
def _add_node(self, node):
node_label = self._style_label(self._get_tuple(node))
self.picture.node(node_label, node_label)
def _add_edges(self, nodeTo, nodeFrom):
self.picture.edge(self._style_label(nodeFrom),
self._style_label(nodeTo))
def _add_dependencies(self, node):
for dep in node.dependencies:
if dep[1] == '__first__':
self._add_edges(
self.graph.root_nodes(dep[0])[0], self._get_tuple(node))
elif dep[1] == '__latest__':
self._add_edges(
self.graph.leaf_nodes(dep[0])[0], self._get_tuple(node))
else:
self._add_edges(dep, self._get_tuple(node))
def render(self, save_loc):
self._create_digraph()
if save_loc:
self.picture.render(save_loc, view=False)
else:
with NamedTemporaryFile() as temp:
self.picture.render(temp.name, view=True)
def get_leaf_node_migrations_for_app(app: Any) -> Dict[str, Any]:
migration_graph = MigrationLoader(None).graph
leaf_migrations = {
migration_name: import_module(f"{app.name}.migrations.{migration_name}")
for app_name, migration_name in migration_graph.leaf_nodes()
if app_name == app.label
}
if not leaf_migrations:
raise Exception(f"Found no migrations for app {app.name}.")
count = len(leaf_migrations)
if count > 2:
raise Exception(f"Too many leaf nodes found for app {app.name}! Found {count}.")
return leaf_migrations
class Command(BaseCommand):
def handle(self, *apps, **options):
self._censor_cache = {}
self._censor_enabled = bool(options['censor'])
if self._censor_enabled:
random.seed(options['random_seed'])
self.graph = MigrationLoader(None).graph
comment = options['comment']
self.picture = Digraph(comment=comment)
save_loc = options['filename']
self._render(save_loc)
def add_arguments(self, parser):
parser.add_argument('--comment',
help='optional comments/captions for the picture')
parser.add_argument('--censor',
action='store_true',
help='censor node names (e.g. for publishing)')
parser.add_argument('--random-seed',
default=0,
type=int,
help='random seed (default: %(default)s)')
parser.add_argument('filename',
nargs='?',
help='a filename to write GraphViz contents to')
def _create_digraph(self):
nodes = sorted(self.graph.nodes.values(), key=self._get_tuple)
for node in nodes:
self._add_node(node)
for node in nodes:
self._add_dependencies(node)
@staticmethod
def _censor(text):
res = []
for word in text.split('_'):
if word not in ('auto', 'initial', 'squashed'):
chars = []
for c in word:
if c not in '0123456789_':
c = chr(random.randint(ord('a'), ord('z')))
chars.append(c)
word = ''.join(chars)
res.append(word)
return '_'.join(res)
def _censor_using_cache(self, text):
try:
return self._censor_cache[text]
except KeyError:
while True:
censored = self._censor(text)
if censored not in self._censor_cache.values():
break
self._censor_cache[text] = censored
return censored
def _style_label(self, tupled_node):
if self._censor_enabled:
tupled_node = [self._censor_using_cache(e) for e in tupled_node]
return '/'.join(tupled_node)
@staticmethod
def _get_tuple(node):
return (node.app_label, node.name)
def _add_node(self, node):
node_label = self._style_label(self._get_tuple(node))
self.picture.node(node_label, node_label)
def _add_edges(self, nodeTo, nodeFrom):
self.picture.edge(self._style_label(nodeFrom),
self._style_label(nodeTo))
def _add_dependencies(self, node):
for dep in node.dependencies:
if dep[1] == '__first__':
self._add_edges(
self.graph.root_nodes(dep[0])[0], self._get_tuple(node))
elif dep[1] == '__latest__':
self._add_edges(
self.graph.leaf_nodes(dep[0])[0], self._get_tuple(node))
else:
self._add_edges(dep, self._get_tuple(node))
def _render(self, save_loc):
self._create_digraph()
if save_loc:
self.picture.render(save_loc, view=False)
else:
with NamedTemporaryFile() as temp:
self.picture.render(temp.name, view=True)
