Node ndvi¶

This is the first node of the workflow. As such, the platform takes cares of providing the inputs to the streaming executable: the list of Landsat catalogue entries you created earlier.

Tip

ciop-copy can handle catalogue entries and download the datasets using the online resources in the metadata

A node requires a job template including:

The path to the streaming executable:
Default parameters
Default configuration

  <jobTemplates>
    <jobTemplate id="py-ndvi">
      <streamingExecutable>/application/py-ndvi/run.py</streamingExecutable>
      <defaultParameters>
  </defaultParameters>
      <defaultJobconf>
        <property id="mapred.task.timeout">9900000000000</property>
      </defaultJobconf>
    </jobTemplate>
  </jobTemplates>

Info

The code for the whole application is available here: https://github.com/Terradue/dcs-python-ndvi

While this job template doesn’t define any parameter, it defines the mapred.task.timeout property which is the wall-time in miliseconds between two logging entries.

Note

Log entries using ciop-log function in bash (or rciop.log in R and cioopy.log in Python) tell the platform the process is alive. If the wall-time is reached the execution is terminated with an error