In setup.py or pip requirements file, how to control order of installing package dependencies?

Question

I\'ve got a Python package with its setup.py having dependencies declared via the usual way, in install_requires=[...]. One of the packages there, scikits.timeseries, has a

Answer 1

Here's a solution which actually works. It's not an overly "pleasant" method to have to resort to, but "desperate times...".

Basically, you have to:

• Override the setuptools "install command" class (plus the closely related analogs)
• Execute pip from the script via command line statements for which you can enforce the order

The drawbacks to this are:

• Pip must be installed. You can't just execute setup.py in an environment without that.
• The console output of the initial "prerequisite" installs don't appear for some weird reason. (Perhaps I'll post an update here down the line fixing that...)

The code:

from setuptools import setup

# Override standard setuptools commands. 
# Enforce the order of dependency installation.
#-------------------------------------------------
PREREQS = [ "ORDERED-INSTALL-PACKAGE" ]

from setuptools.command.install import install
from setuptools.command.develop import develop
from setuptools.command.egg_info import egg_info

def requires( packages ): 
    from os import system
    from sys import executable as PYTHON_PATH
    from pkg_resources import require
    require( "pip" )
    CMD_TMPLT = '"' + PYTHON_PATH + '" -m pip install %s'
    for pkg in packages: system( CMD_TMPLT % (pkg,) )       

class OrderedInstall( install ):
    def run( self ):
        requires( PREREQS )
        install.run( self )        

class OrderedDevelop( develop ):
    def run( self ):
        requires( PREREQS )
        develop.run( self )        

class OrderedEggInfo( egg_info ):
    def run( self ):
        requires( PREREQS )
        egg_info.run( self )        

CMD_CLASSES = { 
     "install" : OrderedInstall
   , "develop" : OrderedDevelop
   , "egg_info": OrderedEggInfo 
}        
#-------------------------------------------------

setup ( 
     ...
    install_requires = [ "UNORDERED-INSTALL-PACKAGE" ],
    cmdclass = CMD_CLASSES
)