ECG is a program that automates software environment checking for scientific artifacts.
It is meant to be executed periodically to analyze variations in the software environment of the artifact through time.
## How it works
ECG takes as input a JSON configuration telling where to download the artifact, where to find the Dockerfile to build in the artifact, and which package managers are used by the Docker container.
It will then download the artifact, build the Dockerfile, and then create a list of the installed packages in the Docker container. It also stores the potential errors encountered when building the Dockerfile, and logs the hash of the artifact for future comparison.
## Setup
A Linux operating system and the following packages are required:
-`<config_file>` is the configuration file of the artifact in JSON format. A template of the Nickel file to use to produce the JSON config file is given in `artifacts/nickel/template.ncl`. WARNING: The name of the file (without the extension) must comply with the Docker image naming convention: only characters allowed are lowercase letters and numbers, separated with either one "." maximum, or two "_" maximum, or an unlimited number of "-", and should be of 128 characters maximum.
-`<cache_directory>` is the path to the cache directory, where downloaded artifacts will be stored for future usage. If not specified, cache is disabled.
The list of packages installed in the container, depending on the package managers, Git packages and other miscellaneous packages given in the config file, in the form of a CSV file, with the following columns in order:
For Git packages, the hash of the last commit is used as version number. For miscellaneous packages, the hash of the file that has been used to install the package is used as version number.
-`job_time_exceeded`: When running on a batch system such as OAR, this error indicates that the script exceeded the allocated run time and had to be terminated.