Install Google App Engine on Ubuntu 12.10

Google App Engine  is currently on version 1.7.4 and Ubuntu has recently released Ubuntu 12.10 (Quantal Quetzal). Quantal Quetzal comes with Python 2.7 installed, and App Engine has been providing that version of Python as an option since February 2012. So if you are starting a new App Engine project, it's probably a good time to move to Python 2.7.

I'll explain briefly how you start a new project and there's a nice clean copy of the code at the bottom that you can cut and paste.

Let's get the show on the road. Choose a name for the project and create and switch to a virtual environment:

PROJ=gae_project
mkvirtualenv ${PROJ}
cdvirtualenv

Note that note that "--no-site-packages" and "--distribute" are now the defaults for mkvirtualenv. You don't even need to use "--python=python2.7" on Ubuntu 12.10.

Now we need to know what the latest version of App Engine is, but as of writing it's 1.7.4:

GAE=1.7.4
wget -O /tmp/gae.zip http://googleappengine.googlecode.com/files/google_appengine_${GAE}.zip
unzip /tmp/gae.zip

Now let's create an App Engine app. The app will need a name that has been created in the App Engine Console:

GAE_APP_NAME=dummy
mkdir -p gae_app/static

Now create the app.yaml file:

echo """application: ${GAE_APP_NAME}
version: development
runtime: python27
api_version: 1
threadsafe: true

default_expiration: 7d

handlers:
- url: /static
  static_dir: static
- url: .*
  script: wsgi_app.app
""" > gae_app/app.yaml

And finally the app itself:

echo """import webapp2

class MainPage(webapp2.RequestHandler):
  def get(self):
      self.response.headers['Content-Type'] = 'text/plain'
      self.response.out.write('Please replace me with a decent WSGI App Framework such as Flask')

app = webapp2.WSGIApplication([('/', MainPage)],
                              debug=True)
""" > gae_app/wsgi_app.py

And finally to run the development server:

python ./google_appengine/dev_appserver.py gae_app/

I hope that this has all been of some help to you. Did I miss anything? Please comment below.

Install Stackless Python on Ubuntu

I'm just about to write a couple of posts on Stackless Python and the Nagare Micro Framework which runs on it. So I've been installing Stackless on my Ubuntu 12.04. Here are some nice copy and paste instructions if you want to play along.

First install the required libraries and get stackless itself:

Now install stackless :

After the "make" you'll see some failures as below. Just ignore them.

Now it's time to link your standard (CPython) packages so that they can be used with stackless:

...and edit the paths in the site.py file. At about line 300, edit the file to look like this. It's the second sitepackages.append bit we're adding here:

That should be it! Let's test it:

Install Google App Engine on Ubuntu 12.04

If you want to use Google App Engine on Ubuntu there are a couple of things to note. Firstly GAE has recently moved to version 1.6.5 and secondly Ubuntu has recently released Ubuntu 12.04 (Precise Pangolin). Precise Pangolin is a Long Term Support (LTS) version of Ubuntu to come with Python 2.7 installed, and App Engine has been providing it as an option since February 2012. So if you are starting a new App Engine project, it's probably a good time to move to Python 2.7.

I'll explain briefly how you start a new project and there's a nice clean copy of the code at the bottom that you can cut and paste.

Let's get the show on the road. Choose a name for the project and create and switch to a virtual environment:

PROJ=py27_gae_project
mkvirtualenv ${PROJ}
cdvirtualenv

Note that note that "--no-site-packages" and "--distribute" are now the defaults for mkvirtualenv. You don't even need to use "--python=python2.7" on Ubuntu 12.04.

Now we need to know what the latest version of App Engine is, but as of writing it's 1.6.5:

GAE=1.6.5
wget -O /tmp/gae.zip http://googleappengine.googlecode.com/files/google_appengine_${GAE}.zip
unzip /tmp/gae.zip

Now let's create an App Engine app. The app will need a name that has been created in the App Engine Console:

GAE_APP_NAME=dummy
mkdir -p gae_app/static

Now create the app.yaml file:

echo """application: ${GAE_APP_NAME}
version: development
runtime: python27
api_version: 1
threadsafe: true

default_expiration: 7d

handlers:
- url: /static
  static_dir: static
- url: .*
  script: wsgi_app.app
""" > gae_app/app.yaml

And finally the app itself:

echo """import webapp2

class MainPage(webapp2.RequestHandler):
  def get(self):
      self.response.headers['Content-Type'] = 'text/plain'
      self.response.out.write('Please replace me with a decent WSGI App Framework such as Flask')

app = webapp2.WSGIApplication([('/', MainPage)],
                              debug=True)
""" > gae_app/wsgi_app.py

And finally to run the development server:

python ./google_appengine/dev_appserver.py gae_app/

I hope that this has all been of some help to you. Did I miss anything? Please comment below.

Github: Who needs it?

Do you ever think that you just don't want all your code on Github? I mean it's only a quick hack right?

Truth is, once you start using git you probably use it automatically for all your code, but you don't always want all your code floating around the net. What about those hard-coded email addresses and API tokens, or those references to your private net servers?

The answer is probably so simple that you have just overlooked it. You don't need to set up a local git server or hire one from Amazon. All you need to do is use DropBox or Ubuntu One as your remote origin repository.

Here's how, using Ubuntu One on Ubuntu:

Write a short shell script something like this and save it on your path as repo.sh.

Now when you want to create a new repository all you have to do is:

If you use Python and virtualenv you may be interested in the slightly extended script at http://pythonic-apis.blogspot.com/2012/01/using-ubuntu-one-as-git-repository.html.

Set Up Your Own Git Repository Hosting Service in Three Minutes

You might have seen my earlier post "A Review of Free Code Repositories".

Well I forgot about hosting your own. Really handy for hobbyist development. I have one of those free developer servers from Amazon out there somewhere. I don't use it much except to demo the occasional site and so on.

I decided that it was a good idea to set it up as a git repository and i show you here how to do this. If you are using something Ubuntu-ish remotely then this should take about three minutes.

A Word of Explanation
This is the simple setup, it avoids creating 'git' user on the remote server, but you DO need to use a seperate key for using the git service and I show you that first.

On your local machine:

# echo "Host gitserver
  Hostname ec2-XXX-XXX-XXX-XXX.compute-1.amazonaws.com
  User git-col
  PreferredAuthentications publickey
  IdentityFile ~/keys/git-col.pub
" >> ~/.ssh/config

# mkdir ~/keys

# ssh-keygen
Generating public/private rsa key pair.
Enter file in which to save the key (/home/col/.ssh/id_rsa): git-col.pub # do NOT accept the default

# cp git-col* ~/keys
# scp git-col.pub ec2-XXX-XXX-XXX-XXX.compute-1.amazonaws.com:
# ssh 
ec2-XXX-XXX-XXX-XXX.compute-1.amazonaws.com

On your remote host you are now logged in as 'ubuntu':

# sudo apt-get install git
# git clone git://github.com/sitaramc/gitolite
# ./gitolite/src/gl-system-install 
# gl-setup -q ~/git-col.pub 
# exit

On your local machine:

# git config --global user.name "Your Name"
# git config --global user.email your@email.address
# git clone gitserver:gitolite-admin
# exit

That's it really. To create a new repository called dummy and initialize it, you can do something like this.

On your local machine:

# set the new repository name
export repo=dummy

# update the gitolite conf file with your new repository
cd ~/gitolite-admin
echo "        repo    ${repo}" >> conf/gitolite.conf
echo "                RW+     =   @all" >> conf/gitolite.conf

# push the config to your server
git commit -m "added new repository ${repo}" conf/gitolite.conf
git push 

# make sure you cd to an existing directory!
mkdir ~/Projects
cd ~/Projects

# pull back the new empty repository
git clone gitserver:${repo}

# go to repository and make any change
cd ${repo}
echo "*.pyc" >> .git/info/exclude # I use python
touch README

# do your first push back to master
git add .
git commit -am "repository ${repo} pushed to origin on gitserver"
git push origin master

You'll be using that last code section again, so you might want to make it into a script.

Never type anything you don't understand. 

If I've made any mistakes then please let me know.