CPLEX Nix Environment

This is a Nix flake template for setting up an IBM ILOG CPLEX Optimization Studio environment.

Motivation

I had the need to create this because the nixpkgs cplex installer was failing during installPhase with this error:

Running phase: installPhase
mv: cannot stat '/nix/store/rwnwq5m6fhc0vsyrzg9p890i40hbsjyr-cplex-22.12/doc': No such file or directory
       > Running phase: installPhase
       > mv: cannot stat '/nix/store/rwnwq5m6fhc0vsyrzg9p890i40hbsjyr-cplex-22.12/doc': No such file or directory
       For full logs, run 'nix log /nix/store/333yavk6iq6442jwaci1bhwsrdny8x79-cplex-22.12.drv'.

Which seems to occur if doc or license directories are not found in the installation path. This issue has been addressed by conditionally checking their existance here as following:

    if [ -d "$out/doc" ]; then
      mkdir -p $out/share/doc
      mv $out/doc $out/share/doc/$name
    else
      echo "No doc directory found, skipping doc installation"
    fi

    if [ -d "$out/license" ]; then
      mkdir -p $out/share/licenses
      mv $out/license $out/share/licenses/$name
    else
      echo "No license directory found, skipping license installation"
    fi

Furthermore this also allows upgrading to cplex latest version (22.12).

Prerequisites

• Nix with flakes enabled
• An IBM CPLEX installer (you need to download this yourself from IBM)

Setup Instructions

1. Initialize a new project from this template:

   nix flake init -t github:elenaferr0/cplex-nix

2. Download your CPLEX installer from IBM: https://www.ibm.com/support/pages/downloading-ibm-ilog-cplex-optimization-studio-2212

3. Update the flake.nix file to point to your CPLEX installer:

   cplex = pkgs.callPackage ./cplex.nix {
     releasePath = ./path/to/your/cplex.bin;
   };

4. Update the devShell section to include the cplex package:

   buildInputs = [
     cplex
     pkgs.curl
     pkgs.python3
     # Other packages...
   ];

5. Enter the development environment:

   nix develop -c $SHELL

   In case you did not enable unfree packages you will need to run the following command instead:

   NIXPKGS_ALLOW_UNFREE=1 nix develop --impure -c $SHELL

Environment Variables

When properly configured, the environment sets up:

• CPLEX_STUDIO_DIR: Points to the CPLEX installation
• CPLEX_BIN_DIR: Points to the CPLEX binary directory
• LD_LIBRARY_PATH: Includes the CPLEX library path

License

The CPLEX software requires a valid license from IBM. This template only helps with the Nix environment setup.