.. NutShell documentation, description


.. _nutshell-variables:

==================
NutShell Variables
==================

.. _system-variables:

System variables
================

=============== ============================ ==================
Variable        Description                  Example  
=============== ============================ ==================
``PRODUCT``     Product id, eg.              "my.test.product"  
``TIMESTAMP``   Numeric time or "LATEST"<br> "201708121600"
                or "LATEST" or "TIMESTAMP"
\\-- ``YEAR``    Year (4 digits)             "2017"
\-- ``MONTH``   Month (2 digits)             "08"
\-- ``DAY``     Day (2 digits)               "12"
\-- ``HOUR``    Hour (2 digits)              "16"
\-- ``MINUTE``  Minute (2 digits)            "00"
``PARAMETERS``  Product specific variables   {"SIZE": "300", "NAME": "X"}
\-- ``<KEY>``   Name of a variable           "300"             
\-- ``<KEY>``   Name of a variable           "X"             
\--  ...        ...                          ...             
``EXTENSION``   File format, 
                including compression        "txt.gz"
``FORMAT``      File format                  "txt"
``COMPRESSION`` File compression             "gz"
=============== ============================ ==================

In code, nutshell.product.Info provides parsing of above parameters.

Part of the variables come from :ref:`configuration` files read by
nutshell.nutshell.ProductServer .


Variable parsing scheme
=======================
   
Parsing can be tested interactively:

>>> import nutshell.product
>>> p = nutshell.product.Info("201708121600_my.test.product_SIZE=300.pgm.gz")

.. image:: img/nutshell-variables-dot.png