Asterix specifications

This project uses .xml files for asterix definitions. The .xml files can be created and maintained by editing the files directly, however a prefered approach is to convert existing definition files instead.

Basic conversion flow:

(unstructured).pdf → .ast ↔ .json → .xml

This directory contains a script to convert asterix definitions from .json to .xml format.

Asterix specification formats

• Original asterix definitions are defined as unstructured (free text) .pdf files by eurocontrol.

• A structured version of the specifications is available in .ast and .json formats. Custom .ast format uses a low overhead syntax and is used to maintain the specifications. A converter exists, as part of asterix-specs project, to convert between .ast and .json syntaxes in both directions transparently.

• .json files are in turn converted to the target .xml format, using a script from this directory.

In case of problems in asterix definitions, users of this project are encouraged to report problems upstream.

Running asterixjson2xml.py script

NOTE: asterixjson2xml.py script requires python36 or higher.

Basic conversion example:

# check python version
python3 --version

# download definition in .json format
curl https://zoranbosnjak.github.io/asterix-specs/specs/cat062/cats/cat1.18/definition.json > input.json

# convert json to xml
python3 asterixjson2xml.py < input.json > output.xml

# or directly
curl https://zoranbosnjak.github.io/asterix-specs/specs/cat062/cats/cat1.18/definition.json | python3 asterixjson2xml.py

Combine CAT+REF definition to a single xml:

python3 asterixjson2xml.py --cat category.json --ref ref.json --outfile out.xml

Running update-specs.py script

This scripts autimatically reads latest Asterix specifications from asterix-specs-out and creates all XML definitions in specs folder.

python3 update-specs.py

Conversion workflow when .json file is available

• download .json file;
• convert .json to .xml;
• review generated .xml file;
• compare new .xml file with an old one (if exists);
• commit new/changed .xml file to this repository;

NOTE: If the resulting .xml file in not as expected, check/modify the asterixjson2xml.py script.

NOTE: Do not manually edit converted .xml files if possible.

Updating asterix specifications

Asterix specifications shall be extended/modified in the upstream asterix-specs project.

Procedure:

• clone asterix-specs project;
• add/modify .ast file(s);
• validate file(s) using a converter;
• the same converter can be used to convert to .json for local testing;
• pretify modified .ast files, using a converter.
• review changes by peer reviewer, make sure that changes are correct and complete;
• create pull request to make the changes available to others;