Trollflow2 YAML File Configuration
Welcome to this Wiki-Tutorial, where you will find information on how to configure properly a Trollflow2 YAML file. Specifically, in this page we will follow the case of setting up an operational Trollflow2 YAML file that executes a chain production of satellite imagery with MSG HRIT SEVIRI data.
The first and most necessary step is to create a .yaml file inside /home/user/dockers/pytroll/mnt/trollflow2/config_seviri_hrit (or the related path you may have defined in your machine).
Inside this folder we should have such file named trollflow2_seviri_hrit.yaml which will contain all the information related to our satellite processing set up.
At the top of the file we first define the output directory, the subscribe and publish topic, the reader, the filename pattern and the sun zenith latitude and longitude.
If delay_composites: True, Trollflow will consider if the composites you will select later share some channels, and if that is the case (mostly true), the images will be processed in a single batch instead of one by one.
Since we establish that in this tutorial we will be working with MSG HRIT SEVIRI data, for this first step, you should have something similar to this in terms of parameters:
For this second step we need to refer to the areas.yaml file we should have inside the same folder. And indeed, we are selecting an area in a file based on the definition of such area inside a different file.
If we take a look inside areas.yaml, we can find the following information:
We can either select one of the predefined areas Pytroll offers, or create a custom one. If you want to create a custom one, it is possible if you know the parameters that define such area.
euro1:
description: Euro 4km area - Europe
projection:
proj: stere
ellps: bessel
lat_0: 90.0
lon_0: 14.0
lat_ts: 60.0
shape:
height: 4096
width: 4096
area_extent:
lower_left_xy: [-2717181.7304994687, -5571048.14031214]
upper_right_xy: [1378818.2695005313, -1475048.1403121399]
In this third section is where we can select which product will get developed. The main principle is basically writing the standard name of a composite, which is usually the same as the product name. After that we should repeat the following information for as many types of image formats as we wish to have.
- Overlay: Coast and border lines can be added on the images. For that, in the folder where we assign
/mnt/shapesinside the container, id
This is the last step of the file and it should usually look like this:
