##pc2

PC2 is a workflow orchestration framework for incorporating varied earth data analytic modules as a unified solution.

Conda environment setup:

 >> conda create -n stratus -c conda-forge python=3.6 libnetcdf netCDF4 pyyaml six xarray networkx requests decorator

Install Celery and Redis:

>> pip install "celery[redis]"

Start Redis

>> redis-server

Build PC2 installation by installing the pc2-module and pc2 packages:

>> git clone https://github.com/nasa-nccs-cds/pc2-module.git
>> cd pc2-module
>> python setup.py install

> git clone https://github.com/nasa-nccs-cds/pc2.git
> cd pc2
> python setup.py install <handlers(s)>

The handlers(s) qualifier in the last install command tells the builder to include dependencies for the listed optional services. To build a pc2 instance that supports both the celery and zeromq services one would execute “python setup.py install celery zeromq”, or for only rest: “python setup.py install rest”. The purpose of building an instance without Celery would be to stand up a remote module that connects to the process controller via zmq or rest (and can be installed in a celery-free environment).

Following are the optional pc2 services:

• zeromq
• celery
• rest
• rest_client

To generate CURVE certificates for zmq security you can execute the script stratus/handlers/zeromq/security/generate_certificates.py. The certificates will, by default, be written to the ~/.stratus/zmq directory, which is the default location where zmq will look for them. The certificate path will need to be specified using the certificate_path parameter in the stratus configuration if the certificates are stored elsewhere.

In order to expose some capability within the pc2 framework, that capability must be wrapped as a pc2 module. Examples of PC2 module wrappings can be found in the pc2/handlers/module/samples directory.