Management Command to Visualize Model Relationships
2011-06-17 16:09 (13 years ago)
ytyng
# -*- coding: utf-8 -*-
"""
Django management command to visualize model relations
management/commands/view_models_relation.py
./manage.py view_models_relation
+ django.contrib.auth.models.Group
+ django.contrib.auth.models.User
| + django.contrib.auth.models.Message
| + django.contrib.admin.models.LogEntry
+ django.contrib.contenttypes.models.ContentType
| + django.contrib.auth.models.Permission
| + django.contrib.admin.models.LogEntry
+ django.contrib.sessions.models.Session
+ django.contrib.sites.models.Site
+ south.models.MigrationHistory
"""
from optparse import make_option
from django.core.management.base import BaseCommand
from django.db import models
from django.utils.encoding import smart_str
from django.conf import settings
from django.utils.importlib import import_module
class Command(BaseCommand):
help = 'print model relation'
args = '<app_name>'
option_list = BaseCommand.option_list + (
make_option('--verbose',
action='store_true',
dest='verbose',
default=False,
help='Verbose message output'),
)
def echo(self, message):
"""
Example: self.echo(self.style.NOTICE('NG!'))
"""
self.stdout.write(smart_str(message, errors='ignore'))
self.stdout.write('\n')
self.stdout.flush()
def echo_verbose(self, message):
if self._verbose:
return self.echo(message)
def handle(self, app_label=None, **options):
self._verbose=options.get('verbose', False)
# Import APP
for app_name in settings.INSTALLED_APPS:
try:
import_module('.management', app_name)
except ImportError as exc:
msg = exc.args[0]
if not msg.startswith('No module named') or 'management' not in msg:
raise
if app_label:
app_list = [models.get_app(app_label)]
else:
app_list = models.get_apps()
self.childs_dict = {} # List of children
#self.parents_dict = {} # List of parents
primitive_models = [] # No relations at all
for app in app_list:
if not app_label:
self.echo_verbose('=' * 50)
self.echo_verbose('App: %s' % app)
app_models = models.get_models(app)
if not app_models:
self.echo_verbose('No app models.')
for app_model in app_models:
self.echo_verbose('-' * 50)
app_model_name = self.get_model_path(app_model)
self.echo_verbose('app_model_name=%s' % app_model_name)
has_parent = False
for field in app_model._meta.fields:
field_class_name = field.__class__.__name__
if field_class_name == 'ForeignKey' or \
field_class_name == 'OneToOneField' or \
field_class_name == 'ManyToManyField':
self.echo_verbose('related_field: %s' % field.name)
related_model = field.related.parent_model
rmn = self.get_model_path(related_model)
self.echo_verbose('related_model: %s' % rmn)
self.append_dict_list(self.childs_dict, rmn, app_model_name)
#self.append_dict_list(self.parents_dict, app_model_name, rmn)
has_parent = True
if not has_parent:
primitive_models.append(app_model_name)
for primitive_model in primitive_models:
self.print_child(primitive_model)
def print_child(self, model_name, depth=0):
indent = ("| " * depth)
self.echo(indent +"+ "+ model_name)
if model_name in self.childs_dict:
child_models = self.childs_dict[model_name]
for child_model in child_models:
if child_model == model_name:
self.echo(indent +"+ " + child_model + " (self relation)")
else:
self.print_child(child_model, depth=depth+1)
def append_dict_list(self, d, k, v):
"""
Dictionary d has a list as its value.
Add an item to that list. If it doesn't exist, create a new list.
"""
if k in d:
d[k].append(v)
else:
d[k] = [v]
def get_model_path(self, model_class):
return "%s.%s" % (model_class.__module__, model_class.__name__)
The author runs the application development company Cyberneura.
We look forward to discussing your development needs.
We look forward to discussing your development needs.