`0.0.0.0:80` is a shortcut meaning &quot;bind to all IP addresses this computer supports&quot;. `127.0.0.1:80` makes it bind only to the &quot;lo&quot; or &quot;loopback&quot; interface. If you have just one [NIC][1] with just one IP address, you could bind to it explicitly with, say, `192.168.1.1:80` (if `192.168.1.1` was your IP address), or you could list all the IPs your computer responds to, but `0.0.0.0:80` is a shortcut for that.


  [1]: http://en.wikipedia.org/wiki/Network_interface_controller

127.0.0.1 is the [loopback interface][1], also known as `localhost`; this is an address that is only accessible from the same computer, as nothing actually goes over the network. 0.0.0.0  means &quot;listen on all interfaces&quot;, and thus will listen for connections on all IP addresses that machine has (likely only one).

  [1]: http://en.wikipedia.org/wiki/Loopback

127.0.0.1 is the local (loopback) ip, not the ip of that computer on the network. To access a server across the network, you&#39;ll need to know its&#39; network ip

I have a shape with a gradient that I&#39;m using as a divider between `ListView` items.  I&#39;ve defined it as follows:

    &lt;?xml version=&quot;1.0&quot; encoding=&quot;UTF-8&quot;?&gt;
    &lt;shape
        xmlns:android=&quot;http://schemas.android.com/apk/res/android&quot;
        android:shape=&quot;rectangle&quot;&gt;

    &lt;gradient
        android:startColor=&quot;#ccd0d3&quot;
        android:centerColor=&quot;#b6babd&quot;
        android:endColor=&quot;#ccd0d3&quot;
        android:height=&quot;1px&quot;
        android:angle=&quot;0&quot; /&gt;

    &lt;/shape&gt;

I would like to add 6 pixels of padding on either side of the gradient, so that it doesn&#39;t extend from edge to edge of the screen.

However, no matter where I put an `android:left=&quot;6px&quot;` and `android:right=&quot;6px&quot;`, it doesn&#39;t seem to take effect.  I can put it in the `&lt;shape&gt;` element, the `&lt;gradient&gt;` element, or in a separate `&lt;padding&gt;` child of `&lt;shape&gt;`, and it doesn&#39;t change anything.

How can I add padding on the left and right of my list divider?

How to add padding to gradient &lt;shape&gt; in Android?

Let&#39;s start with a simple test case:

    import java.lang.reflect.Field;
    
    public class Test {
      private final int primitiveInt = 42;
      private final Integer wrappedInt = 42;
      private final String stringValue = &quot;42&quot;;
    
      public int getPrimitiveInt()   { return this.primitiveInt; }
      public int getWrappedInt()     { return this.wrappedInt; }
      public String getStringValue() { return this.stringValue; }
      
      public void changeField(String name, Object value) throws IllegalAccessException, NoSuchFieldException {
        Field field = Test.class.getDeclaredField(name);
        field.setAccessible(true);
        field.set(this, value);
        System.out.println(&quot;reflection: &quot; + name + &quot; = &quot; + field.get(this));
      }
    
      public static void main(String[] args) throws IllegalAccessException, NoSuchFieldException {
        Test test = new Test();
    
        test.changeField(&quot;primitiveInt&quot;, 84);
        System.out.println(&quot;direct: primitiveInt = &quot; + test.getPrimitiveInt());
    
        test.changeField(&quot;wrappedInt&quot;, 84);
        System.out.println(&quot;direct: wrappedInt = &quot; + test.getWrappedInt());
    
        test.changeField(&quot;stringValue&quot;, &quot;84&quot;);
        System.out.println(&quot;direct: stringValue = &quot; + test.getStringValue());
      }
    }

Anybody care to guess what will be printed as output (shown at the bottom as to not spoil the surprise immediately).

The questions are:

 1. Why do primitive and wrapped integer behave differently?
 2. Why does reflective vs direct access return different results?
 3. The one that plagues me most - why does String behave like primitive `int` and not like `Integer`?

Results (java 1.5):

    reflection: primitiveInt = 84
    direct: primitiveInt = 42
    reflection: wrappedInt = 84
    direct: wrappedInt = 84
    reflection: stringValue = 84
    direct: stringValue = 42

Modifying final fields in Java

We&#39;ve got a server over which we&#39;re running a Django powered site. Since we want to test the site, we&#39;re using Django&#39;s build-in development server (i.e `runserver`).  But I&#39;m curious about the ip of the following command:

    python manage.py runserver 0.0.0.0:80

It results in a running site we can visit using server&#39;s ip remotely.  
But when using `127.0.0.1` instead:

    python manage.py runserver 127.0.0.1:80

No one can visit the site with the sever&#39;s ip from another pc.

So why? What does `0.0.0.0` exactly means (Google says it&#39;s the default route) ?  Why can&#39;t `127.0.0.1:80` be accessed remotely?

About IP 0.0.0.0 in Django

We've got a server over which we're running a Django powered site. Since we want to test the site, we're using Django's build-in development server (i.e <code>runserver</code>). But I'm curious about the ip of the following command:
<pre><code class="hljs">python manage.py runserver 0.0.0.0:80
</code></pre>
It results in a running site we can visit using server's ip remotely. 
But when using <code>127.0.0.1</code> instead:
<pre><code class="hljs">python manage.py runserver 127.0.0.1:80
</code></pre>
No one can visit the site with the sever's ip from another pc.
So why? What does <code>0.0.0.0</code> exactly means (Google says it's the default route) ? Why can't <code>127.0.0.1:80</code> be accessed remotely?

How do I find the previous Monday&#39;s date, based off of the current date using Python? I thought maybe I could use: `datetime.weekday()` to do it, but I am getting stuck.

I basically want to find today&#39;s date and Mondays date to construct a date range query in django using: `created__range=(start_date, end_date)`.  

Find Monday&#39;s date with Python

I have a web site which shows different content based on a location
the visitor chooses. e.g: User enters in 55812 as the zip. I know what
city and area lat/long. that is and give them their content pertinent
to that area. My question is how can I store this in a cookie so that
when they return they are not required to always enter their zip code?

I see it as follows:

1. Set persistent cookie based on their area.
2. When they return read cookie, grab zipcode.
3. Return content based on the zip code in their cookie.

I can&#39;t seem to find any solid information on setting a cookie. Any
help is greatly appreciated. 

Django Cookies, how can I set them?

Where should the validation of _model fields_ go in django?

I could name at least two possible choices: in the overloaded .save() method of the model or in the .to_python() method of the models.Field subclass (obviously for that to work you must write custom fields).

Possible use cases:

 - when it is absolutely neccessary to ensure, that an empty string doesn&#39;t get written into the database (blank=False keyword argument doesn&#39;t work here, it is for form validation only)
 - when it is neccessary to ensure, that &quot;choices&quot; keyword argument gets respected on a db-level and not only in admin interface (kind of emulating a enum datatype)

There is also a class-level attribute `empty_strings_allowed` in the models.Field base class definition and derived classes happily override it, however it doesn&#39;t seem to produce any effect on the database level, meaning I can still construct a model with empty-string fields and save it to the database. Which I want to avoid (yes, it is neccessary).

Possible implementations are

on the field level:

    class CustomField(models.CharField):
        __metaclass__ = models.SubfieldBase
        def to_python(self, value):
            if not value:
                raise IntegrityError(_(&#39;Empty string not allowed&#39;))
            return models.CharField.to_python(self, value)

on the model level:

    class MyModel(models.Model)
        FIELD1_CHOICES = [&#39;foo&#39;, &#39;bar&#39;, &#39;baz&#39;]
        field1 = models.CharField(max_length=255, 
                   choices=[(item,item) for item in FIELD1_CHOICES])
        
        def save(self, force_insert=False, force_update=False):
            if self.field1 not in MyModel.FIELD1_CHOICES:
                raise IntegrityError(_(&#39;Invalid value of field1&#39;))
            # this can, of course, be made more generic
            models.Model.save(self, force_insert, force_update)

Perhaps, I am missing something and this can be done easier (and cleaner)?


Django model fields validation

&lt;!-- A Django newbie question: --&gt;

What is the recommended way of handling settings for local development and the production server? Some of them (like constants, etc) can be changed/accessed in both, but some of them (like paths to static files) need to remain different, and hence should not be overwritten every time the new code is deployed.

Currently, I am adding all constants to `settings.py`. But every time I change some constant locally, I have to copy it to the production server and edit the file for production specific changes... :( 

*Edit: looks like there is no standard answer to this question, I&#39;ve accepted the most popular method.*

How to manage local vs production settings in Django?

The django csrf middleware can&#39;t be disabled.  I&#39;ve commented it out from my Middleware of my project but my logins are failing due to missing CSRF issues.  I&#39;m working from the Django trunk.  How can CSRF cause issues if it is not enabled in middleware?

I have to disable it because there are lots of POST requests on my site that CSRF just breaks.  Any feedback on how I can completely disable CSRF in a django trunk project?

The &quot;new&#39; CSRF framework from Django&#39;s trunk is also breaking an external site that is coming in and doing a POST on a URL I&#39;m giving them (this is part of a restful API.)  I can&#39;t disable the CSRF framework as I said earlier, how can I fix this?

Django CSRF framework cannot be disabled and is breaking my site

I want to get the currently running [Android Emulator][1]&#39;s IP address through code.
How can it be achieved?


  [1]: http://en.wikipedia.org/wiki/Android_%28operating_system%29#Software_development_kit

How to get the Android Emulator&#39;s IP address?

Is there a public API from some big company to get my public ip from within a program? 

I&#39;ve found `http://ip-address.domaintools.com/myip.xml`, which is exactly what I want, but unfortunately it blocks Python&#39;s `urllib` as well as many other http libraries, unless you spoof user-agent (anything doing that can&#39;t be called an API at all).

The problem is that I need this data for some potentially open source library, so we have to play by the rules. I also know that I can just do smth like `print $_SERVER[REMOTE_ADDR]`, but I don&#39;t want to server traffic to everyone using my library.

So, is there something like the URL above, but real API, that allows robots?

Getting my public IP via API

I have a simple Node.js program running on my machine and I want to get the local IP address of a PC on which my program is running. How do I get it with Node.js?






Get local IP address in Node.js

Is 0.0.0.0 a valid IP address? I want my program to be able to store it as an indication that no address is in use, but this won&#39;t work if it&#39;s actually valid.

Is 0.0.0.0 a valid IP address?

Is there any Linux command to translate a domain name to an IP address?

Content Type	Original Author	Original Content on Stackoverflow
Question	Zhu Tao	View Question on Stackoverflow
Solution 1 - Django	Paul Tomblin	View Answer on Stackoverflow
Solution 2 - Django	Brian Campbell	View Answer on Stackoverflow
Solution 3 - Django	Adam Hopkinson	View Answer on Stackoverflow

About IP 0.0.0.0 in Django

Django Problem Overview

Django Solutions

Solution 1 - Django

Solution 2 - Django

Solution 3 - Django

Modifying final fields in Java

How to add padding to gradient <shape> in Android?

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