How to be a Ninja 101

This note shows how to change the directory of your virtualenv without breaking the PATH of your packages.

Step 1:

copy & paste the your virtualenv to wherever you want to transfer it.

$ cp -R ~/old_directory/env ~/new_directory/env

Step 2:

Now it will (surely) not work properly and will get a bunch of error messages

go to env’s bin directory to fix the activate script

$ cd ~/new_directory/env/bin

$ nano activate # edit the activate file

then change the VIRTUAL_ENV to the new location of the env

VIRTUAL_ENV=“~/new_directory/env” # In this case

Step 3:

Your virtualenv now will work properly but you need to fix your pip script because the path for the python that is harcoded at the top of the script is still set to the old directory

$ cd ~/new_directory/env/bin

$ nano pip # edit the pip file

At the top most part of the script change the path of your python

#!~/new_directory/env/bin/python

Earlier i was challenged by a celestial being, He wants me to check and fix some designs in his web application but the problem is that it is in PHP (lol).

The main issue is that the project should be run in a webserver and for apps built in php i need to install WAMPP or LAMPP, or XAMPP, or <variable>AMPP and i don't think it is worth the time to download and install those stuff. (123mb for xampp installer?!? oh c'mon i live in the philippines we have 10kbps download speed lol). In addition, i am lazy to do that.

So i was like "screw this! I'm gonna make my own webserver!!"

Here's how i did it:

1st Package: I use BaseHTTPServer that is already a python builtin.

Main script

Note: this needs a handler so it will know what to serve

2nd Handler: I created a custom Handler and specify which type of files to be served.

My Custom Handler is named "ServerHandler"

Output:

Note: I looks ugly!! (trollface). staticfiles are not served because i only set .html and .php to be served.

Add more content types

Output:

Note: Ohohoy! that's what i am talking about!

3rd Polish: while i am working on this i remember baymax from the "big hero 6 movie" so what i did is name my webserver baymax.

Starting the server:

Stop the server:

and it's done! it only took me less than 30mins to do it. Well it's fun though it is the very basic functionality of a webserver. It's best to use those pre-built applications for this purpose. I just build my own coz it is fun!

that's all!

I found this cool script from http://www.macminivault.com. It will check and install mysql to your system. (you can check his blog from the link above)

Just run : bash <(curl -Ls http://git.io/eUx7rg) and the script will do the rest.

In addition:

when installing mysql-python package using pip install you may encounter the error: (EnvironmentError: mysql_config not found)

Just add the path on your bin/activate file

PATH="$PATH:/usr/local/mysql/bin/"

NOTE*: Usually, mysql_config is found on that directory but check yours and add the correct path. reactivate env so the new settings is applied.

Top 400 Python projects on Github; Top 400 Python projects on Github

Lately i have been working on how to install OpenCV in my mac OSX. I noticed that there has been a lot of people who are still having problems installing it so i thought i will post the steps that i did to install it. by this is my setup:

- Mac OSX (mavericks)

- python2.7

- virtualenv

- django1.6.1

Step1:

You need homebrew installed in your machine. follow the guide http://brew.sh

Step 2:

Open your terminal and execute "brew install homebrew/science/opencv"

*Note: This make take a while and if the installation fails, you might have ffmpeg in your machine so execute this instead

'brew install homebrew/science/opencv --env=std"

Step 3:

add this line to your ~/.bash_profile. (this is located on your home directory)

export PYTHONPATH=/usr/local/lib/python2.7/site-packages:$PYTHONPATH

*Note: You might need to re-open your terminal to make it work.

that's all! you can try it by opening python in your terminal and then import cv and if there is no error that means that it worked!

checking if it is properly installed:

python

>>> import cv inside an env: (go to your env directory)

. bin/activate

cd <django project root directory>

python manage.py shell

>>> import cv

Cheers!

- Earvin

Since i started developing web applications i had problems dealing with this issue. Although it's not really a major issue i still find it annoying and sometimes it adds unwanted/duplicate/bad data in the database. ( considering users loves to press F5)

After searching for so long(exaggerating).. i found a solution to this problem lol ;). When you create a view function with a post request you should return using HttpResponseRedirect even redirecting to the same page.

def post_view(request):     if request.method == "POST":         #Process post data         return HttpResponseRedirect(reverse('same_url'))

    return render_to_response(template_name, context,         context_instance=RequestContext(request))

Hello, this note shows how to display the values you set for your ChoiceField in your templates. Some people (including me before Lol).. creates custom template tags just to show these values. It's kinda annoying right? XD

Here's the proper and simplier way to print those: ( example ) Source Code:

Models.py: class AwesomePeople(models.Model): """List of awesome people""" LEVEL = ( ('c', 'Cool Guy'), ('g', 'Genius'), ('h', 'Hardworking'), ('b', 'Beast'), ('n', 'Ninja'), ) name = models.CharField(max_length=255) level = models.CharField(max_length=1, choices=LEVEL)

template.html {% for person in awesome_list %} {{ person.name }} {{ person.get_level_display }} {% endfor %}

 The custom template tag contains some integration and modification to admin site interface. This doesn't modify the core source code of django but instead it overrides some functionalities in Django app. I will add more functionalities when i have time. Enjoy! 

Steps on applying this into your site. ( Same as applying normal custom templatetags)

Step 1: Copy and paste this `templatetags` directory inside your app ( any app ). It should be recognized by Django or else it will raise an error 'invalid templatetag'

Step 2: Override your admin/index.html. If you don't know how to override the admin( customize ), You can search the net. It's pretty simple though, just add an admin directory to your templates directory and copy&paste the admin templates to that folder. In this case just copy the index.html

Step 3: Load the templatetag. {% load custom_admin %} <-- add this above. or this {% load i18n %} to this {% load i18n custom_admin %}. (you'll know what i mean lol)

Step 4: Add ADMIN_APP_ORDER in settings.py and add the apps(the way you want it to be order).

        ex. ADMIN_APP_ORDER = ('app1','app2','app3')

Step 5: No step 5. run it and check if it works. If not I'm sorry bro i failed you.

* Note: The current tag will only re-order the apps in index.html but not the models inside the app but I will updated it with cooler stuff when i have time. You can edit it though. thanks!

File Link: https://www.dropbox.com/s/diq2r0p9nl7lk6k/templatetags.tar.gz

Hey while doing some date time feature in the project i am working with i discover a cool library in python. With this feature i can say "Awesome python is awesome" lol.

Working with dates is really a pain in the ass like getting the number of days in Febuary or number of leap years between a year range(ikr). Python has this "calendar" library that will solve most of your problem regarding dates.

Reference: http://docs.python.org/2/library/calendar.html

Example: Getting the number of days in a month.

Import calendar

days = calendar.monthrange(2013, 2) # 2013 is year and 2 is month [feb]

output is (4, 28) # Where 4 is the weekday of first day of the month and 28 is the number of days in the month you specified.

Easy and Cool right!? You can check for more in the link i posted above.

Here is a simple way of adding comma(,) to item list in django templates.

# List of items in views.py items = ['earvin', 'ronil', 'sonito'] ctx['items'] = items # In templates {% for item in items %}     {% if not forloop.first %}, {% endif %}         {{ item }} {% endfor %}

That's it!

Having problems adding login with validations in your django app? I will show you one of the easiest and very efficient way of implementing this functionality.

In Django we have this AuthenticationForm which is located in django.contrib.auth.forms which we can use for our login feature. It already has data validation that checks if the inputted user account exist, is not active, or is invalid. (see code below)

from django.contrib.auth.forms import AuthenticationForm def user_login(request, template_name="main/login.html"):     """     Login Form with data validation     """     if request.method == "POST":         form = AuthenticationForm(request.POST)         if form.is_valid():             ## Do your Stuff ##     else:         form = AuthenticationForm()     return render_to_response(template_name, ctx,         context_instance=RequestContext(request))

That's it! Easy right? You can also customize this form and add your custom validation ( Which will be my next post because it is hard to type python codes in the blog -____-)

One way of fixing the error "password hashing" when saving users data using model form.

Solution: Customize the save function of your UserForm in your forms.py

This is a way on checking valid email address format in the front-end.

function isValidEmailAddress(email) { var pattern = new RegExp(/^((([a-z]|\d|[!#\$%&'\*\+\-\/=\?\^_`{\|}~]|[\u00A0-\uD7FF\uF900-\uFDCF\uFDF0-\uFFEF])+(\.([a-z]|\d|[!#\$%&'\*\+\-\/=\?\^_`{\|}~]|[\u00A0-\uD7FF\uF900-\uFDCF\uFDF0-\uFFEF])+)*)|((\x22)((((\x20|\x09)*(\x0d\x0a))?(\x20|\x09)+)?(([\x01-\x08\x0b\x0c\x0e-\x1f\x7f]|\x21|[\x23-\x5b]|[\x5d-\x7e]|[\u00A0-\uD7FF\uF900-\uFDCF\uFDF0-\uFFEF])|(\\([\x01-\x09\x0b\x0c\x0d-\x7f]|[\u00A0-\uD7FF\uF900-\uFDCF\uFDF0-\uFFEF]))))*(((\x20|\x09)*(\x0d\x0a))?(\x20|\x09)+)?(\x22)))@((([a-z]|\d|[\u00A0-\uD7FF\uF900-\uFDCF\uFDF0-\uFFEF])|(([a-z]|\d|[\u00A0-\uD7FF\uF900-\uFDCF\uFDF0-\uFFEF])([a-z]|\d|-|\.|_|~|[\u00A0-\uD7FF\uF900-\uFDCF\uFDF0-\uFFEF])*([a-z]|\d|[\u00A0-\uD7FF\uF900-\uFDCF\uFDF0-\uFFEF])))\.)+(([a-z]|[\u00A0-\uD7FF\uF900-\uFDCF\uFDF0-\uFFEF])|(([a-z]|[\u00A0-\uD7FF\uF900-\uFDCF\uFDF0-\uFFEF])([a-z]|\d|-|\.|_|~|[\u00A0-\uD7FF\uF900-\uFDCF\uFDF0-\uFFEF])*([a-z]|[\u00A0-\uD7FF\uF900-\uFDCF\uFDF0-\uFFEF])))\.?$/i); return pattern.test(email); }; // -- test if( !isValidEmailAddress( email ) ) { /* do stuff here */ }

Below are the following ways that you can do to fix this problem when deploying your application to heroku.

1. Check if your requirements.txt exist and is located in your project root directory.

django1.4: project - manage.py - requirements.txt django1.3: settings.py - manage.py - requirements.txt - urls.py

2. Check if your requirements.txt is included in your commit. ( git status ). this file should not be in the list of new files

- requirements.txt is very important in heroku and it should be put in the right directory for heroku to recognize( project root directory).

If you encounter the error: ViewsNotFound and there is no error messages in your error logs. here's a way to find out what is causing the error.

" Open your python shell ( python manage.py shell ) and import the views.py that contains the view function that is missing(even if it's not) " then tadddaaah! you will get the error message that you are expecting.

Hello i will share some ways on how to re-factor your codes in Django using dictionaries. Gonna post this here as my notes and for future references

have you experienced coding a views.py and you pass alot of context to the template( yet they all do the same but uses different model for example). Here is a sample code in your views.py that you can re-factor using dictionaries.

Here's how i made the code simpler and cleaner using dictionary.

* if you noticed the dictionary model_dic has dual purpose. the value is for the Models( of course) but for the keys, I also used them as the context name( cool idea right?). You won't notice much of a difference between the two code but if you have for example 10 types of news then this would work pretty cool.

That's all!.. hope this would help someone out there xD.