env with python ruby

Signed-off-by: Sebastien Varrette <[email protected]>

slides/2016/cloudcom2016/src/_environment.md

@@ -1,7 +1,93 @@
-### RR the DIY Way
+### Environment Management
 
-* Let's see how to reproduce a simple yet practical example!
+* RR assumes that you _Master your environment_
+* Keep it _clean and automated_ by:
+    - Using common building tools \hfill{make, cmake etc.}
+    - Using a constrained environment
+          * Sandboxed Ruby environment \hfill{}`bundler`, `Gemfile`
+          * Sandboxed Python \hfill{}`pip freeze`, [`pyenv`](https://github.com/yyuu/pyenv), [`virtualenv`](https://virtualenv.pypa.io/en/latest/)
+          * VMs or Containers \hfill{}[Vagrant](https://www.vagrantup.com), [Docker](https://www.docker.com/)
+    - Automate its building through cross-platform recipes
+    - Automatically test your recipes for Environment configuration
 
+
+### Controlled Ruby Environment
+
+* Consider using [RVM](https://rvm.io/), [rbenv](http://rbenv.org/) and more importantly  [Bundler](http://bundler.io/)
+     - Bring the flexibility of `Rakefile` (`Makefile` + Ruby)
+     - [Bundler](http://bundler.io/): _reproducible_ running environment **across** developpers
+     - easy configuration through `Gemfile[.lock]` + `bundle` command
+* [RVM](https://rvm.io/):  [sandboxed environment](https://hpc.uni.lu/blog/2014/create-a-sandboxed-python-slash-ruby-environment/) per project (**alternative**: [rbenv](http://rbenv.org/))
+     - easy configuration through `.ruby-{version,gemset}` files
+
+\pause
+
+_Typical setup of a freshly cloned project:_
+
+~~~bash
+$> gem install bundler # assuming it is not yet available
+$> bundle              # clone ruby deps/env as defined in Gemfile*
+$> rake -T             # To list the available tasks
+~~~
+
+\pause
+\vspace*{-1em}
+\wbegin{Recommended Gems}\centering\small
+
+`rake`, `bundler`, `falkorlib`
+
+\wend
+
+### Controlled Python Environment
+
+* [`pip`](https://pypi.python.org/pypi/pip): Python package manager
+      - "nice" python packages: `mkdocs`...
+	  - Windows: install via [Chocolatey](https://chocolatey.org/)
+
+\command{pip install <package> \hfill\textit{\# install <package>}}
+\pause
+\command{pip install -U pip \hfill\textit{\# upgrade on Linux/Mac OS}}
+<!-- \command{python -m pip install -U pip \hfill\textit{\# upgrade on Windows}} -->
+\pause
+
+* Dump python environment to a requirements file
+
+\command{pip freeze -l > requirements.txt \hfill\textit{\# as Ruby Gemfiles }}
+
+
+
+### Pyenv / VirtualEnv / Autoenv
+
+\cbegin{0.6\textwidth}
+
+* [`pyenv`](https://github.com/yyuu/pyenv): $\simeq$ RVM/rbenv for Python
+* [`virtualenv`](https://virtualenv.pypa.io/en/latest/) $\simeq$ RVM Gemset
+* (optional) [`autoenv`](https://github.com/kennethreitz/autoenv)
+    - Directory-based shell environments
+	- easy config through `.env` file. _Ex_:
+
+\column{0.4\textwidth}
+
+\centering\includegraphics[height=0.4\textheight]{pyenv.png}
+
+\cend
+
+
+~~~bash
+# (rootdir)/.env : autoenv configuration file
+pyversion=`head .python-version`
+pvenv=`head .python-virtualenv`
+
+pyenv virtualenv --force --quiet ${pyversion} ${pvenv}-${pyversion}
+# activate it
+pyenv activate ${pvenv}-${pyversion}
+~~~
+
+### Constrained VM environment
+
+* Let's see how to reproduce a simple yet practical example in a _constrained_ and _reproducible_ VM environment.
+
+\vspace*{-1em}
 \wbegin{Challenge 1: Reproduce the Build of these Slides}
 
 * Several **tricky** issues illustrating previous best practices