The YANG Development Kit (YDK) is a Software Development Kit that provides API's that are modeled in YANG. The main goal of YDK is to reduce the learning curve of YANG data models by expressing the model semantics in an API and abstracting protocol/encoding details. YDK is composed of a core package that defines services and providers, plus one or more module bundles that are based on YANG models.

Ubuntu (Debian-based) - The following packages must be present in your system before installing YDK-Py:

$ sudo apt-get install python-pip zlib1g-dev python-lxml libxml2-dev libxslt1-dev python-dev

Centos (Fedora-based) - The following packages must be present in your system before installing YDK-Py:

$ sudo yum install epel-release
$ sudo yum install python-pip python-devel libxml2-devel libxslt-devel libcurl-devel libtool

It is required to install Xcode command line tools, homebrew and the following homebrew packages on your system before installing YDK-Py:

$ xcode-select --install
$ /usr/bin/ruby -e "$(curl -fsSL https://raw.githubusercontent.com/Homebrew/install/master/install)"
$ brew install python pkg-config libssh xml2 curl pcre

You must install the following requirements:

• Python Releases for Windows
• Visual C++ Build Tools

Both Python 2 and 3 are supported. At least, Python2.7 or Python 3.4 must be installed in your system.

You can install the latest model packages from the Python package index. Note that, in some systems, you need to install the new package as root. You get a fully operational YDK environment by installing the cisco-ios-xr bundle which automatically installs all other YDK-related packages (ydk, cisco-ios-xr, openconfig and ietf packages):

$ pip install ydk-models-cisco-ios-xr

Alternatively, you can perform a partial installation. If you only want to install the openconfig bundle and its dependencies (ydk and ietf packages), execute:

$ pip install ydk-models-openconfig

If you only want to install the ietf bundle and its dependencies (ydk package), execute:

$ pip install ydk-models-ietf

If you prefer not to use the YDK packages in the Python package index, you need to install manually the ydk core package and then the model bundles you plan to use. To install the ydk core package, execute:

$ cd core
core$ python setup.py sdist
core$ pip install dist/ydk*.gz

Once you have installed the ydk core package, you can install one more model bundles. Note that some bundles have dependencies on other bundles. Those dependencies are already captured in the bundle package. Make sure you install the desired bundles in the order below. To install the IETF bundle, execute:

core$ cd ../ietf
ietf$ python setup.py sdist
ietf$ pip install dist/ydk*.gz

To install the OpenConfig bundle, execute:

ietf$ cd ../openconfig
openconfig$ python setup.py sdist
openconfig$ pip install dist/ydk*.gz

To install the cisco-ios-xr bundle, execute:

openconfig$ cd ../cisco-ios-xr
cisco-ios-xr$ python setup.py sdist
cisco-ios-xr$ pip install dist/ydk*.gz
cisco-ios-xr$ cd ..

You may want to perform the installation under a Python virtual environment (virtualenv/virtualenvwrapper). A virtual environment allows you to install multiple versions of YDK if needed. In addition, it prevents any potential conflicts between package dependencies in your system.

To install virtual environment support in your system, execute:

$ pip install virtualenv virtualenvwrapper
$ source /usr/local/bin/virtualenvwrapper.sh

In some systems (e.g. Debian-based Linux), you need to install support for Python virtual environments as root:

$ sudo pip install virtualenv virtualenvwrapper
$ source /usr/local/bin/virtualenvwrapper.sh

Create a new virtual environment:

$ mkvirtualenv -p python2.7 ydk-py

At this point, you can perform the quick install or the installation from source described above. Take into account that must not attempt to install YDK as root under a virtual environment.

• Samples can be found under the core/samples directory
• API documentation can be found at http://ydk.cisco.com/py/docs
• Hundreds of samples can be found at https://github.com/CiscoDevNet/ydk-py-samples
• For queries related to usage of the API, please join the YDK community at https://communities.cisco.com/community/developer/ydk

The current YDK release version is 0.5.4 (beta). YDK-Py is licensed under the Apache 2.0 License.