[Django] Changing field widget when when using inlines

For example, if you create a SiteOption model to extend Django's core sites framework you may want to add multiple inlines from one model (SiteOption) for grouping options, like:

General Options

Theme Options

Security Options

SEO Options

"Show me the code!"

	from django import forms
	from django.contrib import admin
	from django.contrib.sites.models import Site
	from django.contrib.sites.admin import SiteAdmin
	from django.utils.translation import ugettext_lazy as _
	from colorful.fields import RGBColorField # third-party app
	from .models import SiteOption
	OPTION_COLOR_VARIABLE_CHOICES = (
	('header_color', _('Header Color')),
	# ...
	)
	OPTION_VARIABLE_CHOICES = (
	('contact_email', _(u'admin@site.com')),
	# ...
	)
	# Register site option model as inline into sites
	# by unregistering Site model first
	class ThemeColorsInlineAdmin(admin.TabularInline):
	model = SiteOption
	verbose_name = _('Theme Color')
	verbose_name_plural = _('Theme Colors')
	extra = 0
	def formfield_for_dbfield(self, db_field, **kwargs):
	if db_field.attname == 'variable':
	# Change variable field's widget with selectbox!
	kwargs['widget'] = forms.Select(
	choices=OPTION_COLOR_VARIABLE_CHOICES)
	if db_field.attname == 'value':
	# change value field's widget with color picker!
	db_field = RGBColorField()
	return super(ThemeColorsInlineAdmin, self).formfield_for_dbfield(
	db_field, **kwargs)
	def get_queryset(self, request):
	"""
	Limit result to get only color variables.
	"""
	qs = super(ThemeColorsInlineAdmin, self).get_queryset(request)
	return qs.filter(variable__in=[f[0] for f in OPTION_COLOR_VARIABLE_CHOICES])
	class SiteOptionInlineAdmin(admin.TabularInline):
	model = SiteOption
	extra = 0
	def formfield_for_dbfield(self, db_field, **kwargs):
	if db_field.attname == 'variable':
	# Change variable field's widget with selectbox!
	kwargs['widget'] = forms.Select(choices=OPTION_VARIABLE_CHOICES)
	return super(SiteOptionInlineAdmin, self).formfield_for_dbfield(db_field, **kwargs)
	def get_queryset(self, request):
	"""
	Limit result to get only non-color variables.
	"""
	qs = super(SiteOptionInlineAdmin, self).get_queryset(request)
	return qs.exclude(variable__in=[f[0] for f in OPTION_COLOR_VARIABLE_CHOICES])
	class MySiteAdmin(SiteAdmin):
	inlines = [ThemeColorsInlineAdmin, SiteOptionInlineAdmin]
	admin.site.unregister(Site)
	admin.site.register(Site, MySiteAdmin)

view raw admin.py hosted with ❤ by GitHub

	from django.db import models
	from django.contrib.sites.models import Site
	from django.contrib.sites.managers import CurrentSiteManager
	class SiteOption(models.Model):
	variable = models.CharField(max_length=80)
	value = models.TextField()
	site = models.ForeignKey(Site)
	objects = models.Manager()
	on_site = CurrentSiteManager()
	class Meta:
	unique_together = (('variable', 'site'),)

view raw models.py hosted with ❤ by GitHub

[Django] Using cloud storage services as default storage backend

To use cloud storage services as default storage backend in Django – or actullay in Python, Apache's Libcloud wrapper can be a nice solution. Because it supports more than 30 providers, and has a huge community.

django-storages-redux app provides storage backends to use in Django. Good news, also supports Apache Libcloud. So you can use more than 30 cloud providers with Django. To install the app execute this:

$ pip install django-storages-redux

Also you must install Apache Libcloud:

$ pip install apache-libcloud

And enable from settings.py by adding following lines:

DEFAULT_FILE_STORAGE = 'storages.backends.apache_libcloud.LibCloudStorage'
DEFAULT_LIBCLOUD_PROVIDER = 'google_storage'
LIBCLOUD_PROVIDERS = {
 'google_storage': {
 'type': 'libcloud.storage.types.Provider.GOOGLE_STORAGE',
 'user': 'yourcloudstorageapikey:)',
 'key': 'yourcloudstorageapisecretkey:)',
 'bucket': 'default-bucket-name',
 }
}

 If you don't create bucket, you can create from shell:

$ ./manage.py shell

$ from storages.backends.apache_libcloud import LibCloudStorage
$ LibCloudStorage('google_storage').driver.create_container('default-bucket-name')

Detecting if an image is really an image

About Technique

HTTP protocol has really cool methods such as HEAD. HEAD method allows you to get only head data instead of head and body. Head data contains mimetype of the body, so we can rely on it to detect if it's really an image. Let's get it with JavaScript...

The Code

Sync Example

	request = new XMLHttpRequest()
	request.onreadystatechange = ->
	if request.readyState is 4
	mimetype = request.getResponseHeader('content-type')
	if mimetype.split('/').shift() is 'image'
	alert 'Image!'
	else
	alert 'Not Image!'
	request.open 'HEAD', 'http://upload.wikimedia.org/wikipedia/commons/5/5b/Ultraviolet_image_of_the_Cygnus_Loop_Nebula_crop.jpg', true
	request.send()

view raw async.coffee hosted with ❤ by GitHub

Async Example

	request = new XMLHttpRequest()
	request.onreadystatechange = ->
	if request.readyState is 4
	mimetype = request.getResponseHeader('content-type')
	if mimetype.split('/').shift() is 'image'
	alert 'Image!'
	else
	alert 'Not Image!'
	request.open 'HEAD', 'http://upload.wikimedia.org/wikipedia/commons/5/5b/Ultraviolet_image_of_the_Cygnus_Loop_Nebula_crop.jpg', true
	request.send()

view raw async.coffee hosted with ❤ by GitHub

As you can see, you can even detect huge images very quickly. ;)

Originally posted at https://coderwall.com/p/qdg71a/detecting-if-an-image-is-really-an-image

Using Nginx on Mac OSX

To install Nginx on your Mac you can use simply brew command:

$ brew install nginx 

Default Nginx server name is localhost with 8080 port. So you can see default Nginx page by entering http://localhost:8080 address. Let's change something:

Changing default server name and port
Nginx.conf located at /usr/local/etc/nginx/nginx.conf dir. Open it with your favorite editor, to me the Vim:

$ vim /usr/local/etc/nginx/nginx.conf

 You'll see default server configuration like this:

server {    listen 8080;    server_name locahost;
    ## other things}

Change them with what you want and save the file. To reload Nginx configuration you should restart Nginx by calling these:

$ sudo nginx -s stop$ sudo nginx 

Including multi server defination from different files
Aww, cool topic. To keep different server definations in different files, you should need to this. Open nginx.conf, locate your cursor to the end of http defination block and simple paste this two lines:

$ include /usr/local/etc/nginx/conf.d/*.conf;
$ include /usr/local/etc/nginx/sites-enabled/*.conf;

Now your can create symlinks to these directories. Of course, don't forget to restart Nginx!

[Django] Farkli App Icerisindeki Model'leri Ayni Grupta Gosterebilmek

Django admin'de birbiri ile alakali olan iki farkli app'iniz mevcutsa, bu modelleriniz asagidaki gibi gorunecektir:

[App 1]
- Model 1
- Model 2
[App 2]
- Model 3

Ancak siz bu goruntuyu istemiyor, asagidaki gibi bir goruntu istiyorsunuz:

[App 1]
- Model 1
- Model 2
- Model 3 

Hosgeldiniz! Yapilmasi gereken islem, App 2 altinda bulunan Model 3'un Meta sinifinda o modelin app'inin aslinda App 1 oldugunu soylemek. Onu da boyle yapiyoruz:

	# app_2.models.py
	from django.db import models
	class Model3(models.Model):
	field = models.CharField(max_length=80)
	class Meta():
	app_label = 'app_1'

view raw model3.py hosted with ❤ by GitHub

Onemli Guncelleme:
Bu degisikligin etkileri sandiginizdan daha buyuk olabilir. Bu islem tam anlami ile Django'nun app mimarisindeki app'inizin adinin degistirilmesi anlamina geliyor. Yani varsayilan olarak app'inizin adi olusturulan klasor ayni iken bunun degistirilmis olmasini sagladik. Buna ek olarak Python'un package yapisi yine klasor adi uzerinden calisacaktir.

Bu guncellemeyi yapmama neden olan case, bu app adini degistirdigim zaman bu Model 3'un Model 2'de Foreign key olarak tanimlandigi yerde hata almaya basladim. Bunun sebebi olaraki su tanimlamaydi:

	# app_1.models.py
	from django.db import models
	class Model2(models.Model):
	field = models.ForeignKey('app_1.Model3')

view raw model2.py hosted with ❤ by GitHub

Artik app adimiz 'app_1' olduguna gore buradakini de gistirmek zorundayiz. Bu durumda modelin refresh edilecegini de uzuntuyle belirtmem gerekiyor. :(

Yazar Olma Sorunsali

Yaklasik bir bucuk sene once buyuk paylasim umutlari ile actigim bloguma ozellikle son bes aydir yazamadigimi fark ettim. Draft olarak birkac paragrafi yazilmis 18 adet yazim bulunmaktaymis. Bunlari sirasiyla tamamlayip daha fazla yazmak niyetindeyim. Yazi yazmak uretkenligimi arttirdigini hatirliyorum. Bunun ustune gidecegim. Hatta yazmanin faydalari da bir konu olarak olabilir! Takipte kalin, degerli gunluk bir tane olan ziyaretcilerim! 21 Subat '14 guncellemesi: (Yazamadi)

[DevOps][Nginx] fastcgi_pass Problems

If you are getting error about fastcgi_pass option like this:

2014/07/31 08:08:39 [error] 3536#0: *6 connect() failed (111: Connection refused) while connecting to upstream, client: 95.95.95.1, server: localhost, request: "GET / HTTP/1.1", upstream: "fastcgi://127.0.0.1:9000", host: "localhost"

or this:

2014/07/31 08:25:07 [crit] 3644#0: *23 connect() to unix:/tmp/php5-fpm.sock failed (2: No such file or directory) while connecting to upstream, client: 95.95.95.1, server: localhost, request: "GET / HTTP/1.1", upstream: "fastcgi://unix:/tmp/php5-fpm.sock:", host: "localhost"

You have probably setted wrong or passive TCP or socket address. You can learn PHP's TCP or socket addsress from /etc/php5/fpm/pool.d/www.conf file. Check lines that starts with these:

listen = 127.0.0.1:9000 ;listen = /tmp/php5-fpm.sock

Destroy ; char from starting, and have fun! Don't forget to restart your PHP or your another service -- like this $ service php5-fpm restart!