ejpm

ejpm

ejpm stands for e^JANA packet manager helper

The main goal of ejpm is to provide easy experience of:

• installing e^JANA reconstruction framework and dependent packages
• unify installation for different environments: various operating systems, docker images, etc.

The secondary goal is to help users with e^JANA plugin development cycle.

TL;DR; example for CentOS/RHEL7

# INSTALL PREREQUESTIES
ejpm req centos ejana         # get list of OS packets required to build jana and deps
sudo yum install ...          # install watever 'ejpm req' shows

# or if you are a lucky bash user (yes, csh is still common in physics):
sudo yum install $(ejpm req centos ejana --all) 

# SETUP EJPM
ejpm --top-dir=<where-to>   # Directory where packets will be installed
ejpm set root `$ROOTSYS`    # (optional) if you have CERN.ROOT or other monster packets: 

# INSTALL PACKETS
ejpm install ejana          # install ejana and dependencies (like genfit, jana and rave)
ejpm install g4e            # install 'Geant 4 EIC' and dependencies (like vgm, hepmc)

# SET RIGHT ENVIRONMENT 
source<$(ejpm env)          # set environment variables, 
source ~/.local/share/ejpm/env.sh  # more convenient way. Use *.csh file for tcsh

Motivation

ejpm is here as there is no standard convention in HEP and NP of how to distribute and install software packages with its dependencies. Some packages (like eigen, xerces, etc.) are usually supported by OS maintainers, while others (Cern ROOT, Geant4, Rave) are usually built by users or other packet managers and could be located anywhere. Here comes "version hell" multiplied by lack of software manpower (e.g. to continuously maintain packages on distros level or even to fix GitHub issues) Still we love our users and try to get things easier for them! So here is ejpm.

At this points ejpm tries to unify experience and make it simple to deploy e^JANA for:

• Users on RHEL 7, 8 and CentOS
• Users on Ubutnu/Debian (and Windows with WSL) **
• Docker and other containers

It should be as easy as > ejpm install ejana to build and install a packet called 'ejana' and its dependencies. But it should also provide a possibility to adopt existing installations and have a fine control over dependencies: > ejpm set root /opt/root6_04_16

ejpm is not:

• It is not a real package manager, which automatically solves dependencies, download binaries (working with GPG keys, etc.), finds fastest mirrors, manage... etc.
• ejpm is not a requirment for e^JANA. It is not a part of e^JANA build system and one can compile and install e^JANA without ejpm

Get ejana installed

Step by step explained instruction:

• Install prerequisites utilizing OS packet manager:

  # To see the prerequesties
  ejpm req ubuntu         # for all packets that ejpm knows
  ejpm req centos ejana   # for ejana and its dependencies only
  
  # To put everything into packet manager 
  apt-get -y install `ejpm req ubuntu --all`   # debian
  yum -y install `ejpm req centos --all`       # centos/centos    
  

  At this point only 'ubuntu' and 'centos' are known words for req command. Put:

  • ubuntu for debian family
  • centos for RHEL and CentOS systems.

  In the future this will be updated to support macOS and to have more detailed versions

• Set top-dir. This is where all missing packets will be installed.

  ejpm --top-dir=<where-to-install-all>
  

• Register installed packets. You may have CERN.ROOT installed (req. version >= 6.14.00). Run this:

  ejpm set root `$ROOTSYS` 
  

  You may set paths for other installed dependencies combining:

  ejpm install ejana --missing --explain    # to see missing dependencies
  ejpm set <name> <path>                    # to set dependency path
  

  Or you may skip this step and just get everything installed by ejpm

• Install ejana and all missing dependencies:

  ejpm install ejana
  

• Set environment. There are 3 ways for doing this this:

  • Dynamically source output of ejpm env command (recommended)

    source <(ejpm env)                # works for bash only
    

  • Save output of ejpm env command to a file (can be useful)

     ejpm env sh  > your-file.sh       # get environment for bash or compatible shells
     ejpm env csh > your-file.csh      # get environment for CSH/TCSH
    

  • Use ejpm generated env.sh and env.csh files (lazy and convenient)

    $HOME/.local/share/ejpm/env.sh    # bash and compatible
    $HOME/.local/share/ejpm/env.csh   # for CSH/TCSH
    

    (!) The files are regenerated each time ejpm <command> changes something in EJPM. If you change db.json by yourself, ejpm doesn't track it automatically, so call 'ejpm env' to regenerate these 2 files

Environment

EJPM_DATA_PATH- sets the path where the configuration db.json and env.sh, env.csh are located

Each time you make changes to packets, EJPM generates env.sh and env.csh files, that could be found in standard apps user directory.

For linux it is in XDG_DATA_HOME:

~/.local/share/ejpm/env.sh      # sh version
~/.local/share/ejpm/env.csh     # csh version
~/.local/share/ejpm/db.json     # open it, edit it, love it

XDG is the standard POSIX paths to store applications data, configs, etc. EJPM uses XDG_DATA_HOME to store env.sh, env.csh and db.json and db.json

You can always get fresh environment with ejpm env command

ejpm env

You can directly source it like:

source<(ejpm env)

You can control where ejpm stores data by setting EJPM_DATA_PATH environment variable.