[3513] Recommended version is now 20.4 and in its own requirements file.

doc/maintaining/installing/install-from-source.rst

@@ -126,11 +126,11 @@ c. Install the Python modules that CKAN requires into your virtualenv:
 
        pip install -r |virtualenv|/src/ckan/requirements.txt
 
-d. Upgrade 'setuptools':
+d. Install the recommended version of 'setuptools':
 
    .. parsed-literal::
 
-       pip install -U setuptools       
+       pip install -r |virtualenv|/src/ckan/requirement-setuptools.txt
 
 e. Deactivate and reactivate your virtualenv, to make sure you're using the
    virtualenv's copies of commands like ``paster`` rather than any system-wide

requirement-setuptools.txt

@@ -0,0 +1 @@
+setuptools==20.4

setup.py

@@ -17,18 +17,18 @@
 from ckan import (__version__, __description__, __long_description__,
                   __license__)
 
-MIN_SETUPTOOLS_VERSION = 18.5
-SUGGESTED_SETUPTOOLS_VERSION = 18.5
+MIN_SETUPTOOLS_VERSION = 20.4
 assert setuptools_version >= str(MIN_SETUPTOOLS_VERSION) and \
     int(setuptools_version.split('.')[0]) >= int(MIN_SETUPTOOLS_VERSION),\
     ('setuptools version error'
      '\nYou need a newer version of setuptools.\n'
-     'You have {current}, you need at least {minimum} and the suggested '
-     'version is {suggested}.\nDo this:\n'
-     '    pip install setuptools=={suggested}\n'
+     'You have {current}, you need at least {minimum}'
+     '\nInstall the recommended version:\n'
+     '    pip install -r requirement-setuptools.txt\n'
      'and then try again to install ckan into your python environment.'.format(
-         current=setuptools_version, minimum=MIN_SETUPTOOLS_VERSION,
-         suggested=SUGGESTED_SETUPTOOLS_VERSION))
+         current=setuptools_version,
+         minimum=MIN_SETUPTOOLS_VERSION
+         ))
 
 
 entry_points = {