+ scons_python_usability_improvements2 (springmeyer)

SConstruct

@@ -20,6 +20,7 @@
 
 
 import os, sys, platform
+from subprocess import Popen, PIPE
 
 def color_print(color,text,newline=True):
     # 1 - red
@@ -32,6 +33,13 @@ def color_print(color,text,newline=True):
     else:
         print text
 
+def call(cmd):
+    stdin, stderr = Popen(cmd,shell=True,stdout=PIPE,stderr=PIPE).communicate()
+    if not stderr:
+      return stdin.strip()
+    else:
+      color_print(1,'Problem encounted with SCons scripts, please post bug report to: http://trac.mapnik.org')
+
 # Helper function for uniquely appending paths to a SCons path listing.
 def uniq_add(env, key, val):
     if not val in env[key]: env[key].append(val)
@@ -93,6 +101,7 @@ opts.Add(BoolVariable('DEBUG', 'Compile a debug version of Mapnik', 'False'))
 
 # Install Variables
 opts.Add('PREFIX', 'The install path "prefix"', '/usr/local')
+opts.Add('PYTHON_PREFIX','Custom install path "prefix" for python bindings (default of no prefix)','')
 opts.Add('DESTDIR', 'The root directory to install into. Useful mainly for binary package building', '/')
 
 
@@ -126,7 +135,6 @@ opts.Add(PathVariable('PROJ_LIBS', 'Search path for PROJ.4 library files', '/usr
 # Variables affecting rendering back-ends
 opts.Add(BoolVariable('INTERNAL_LIBAGG', 'Use provided libagg', 'True'))
 
-
 # Variables for optional dependencies
 # Note: cairo, cairomm, and pycairo all optional but configured automatically through pkg-config
 # Therefore, we use a single boolean for whether to attempt to build cairo support.
@@ -142,7 +150,7 @@ opts.Add(PathVariable('OCCI_INCLUDES', 'Search path for OCCI include files', '/u
 opts.Add(PathVariable('OCCI_LIBS', 'Search path for OCCI library files', '/usr/lib/oracle/10.2.0.3/client/'+ LIBDIR_SCHEMA, PathVariable.PathAccept))
 
 # Other variables
-opts.Add(PathVariable('PYTHON','Python executable', sys.executable))
+opts.Add(PathVariable('PYTHON','Full path to Python executable used to build bindings', sys.executable))
 opts.Add(ListVariable('BINDINGS','Language bindings to build','all',['python']))
 opts.Add(EnumVariable('THREADING','Set threading support','multi', ['multi','single']))
 opts.Add(EnumVariable('XMLPARSER','Set xml parser ','libxml2', ['tinyxml','spirit','libxml2']))
@@ -512,18 +520,49 @@ else:
             color_print(1,"Cannot run python interpreter at '%s', make sure that you have the permissions to execute it." % env['PYTHON'])
             Exit(1)
     
-        env['PYTHON_PREFIX'] = os.popen("%s -c 'import sys; print sys.prefix'" % env['PYTHON']).read().strip()
+        sys_prefix = "%s -c 'import sys; print sys.prefix'" % env['PYTHON']
-        env['PYTHON_VERSION'] = os.popen("%s -c 'import sys; print sys.version'" % env['PYTHON']).read()[0:3]
+        env['PYTHON_SYS_PREFIX'] = call(sys_prefix)
-    
+        
-        color_print(4,'Bindings Python version... %s' % env['PYTHON_VERSION'])
+        site_packages = "%s -c 'from distutils.sysconfig import get_python_lib; print get_python_lib()'" % env['PYTHON']
-    
+        env['PYTHON_SITE_PACKAGES'] = call(site_packages)
+        
+        sys_version = "%s -c 'import sys; print sys.version'" % env['PYTHON']
+        env['PYTHON_VERSION'] = call(sys_version)[0:3]
+        
+        py_includes = "%s -c 'from distutils.sysconfig import get_python_inc; print get_python_inc()'" % env['PYTHON']
+        env['PYTHON_INCLUDES'] =  call(py_includes)
+
+        # if user-requested custom prefix fall back to manual concatenation for building subdirectories
+        py_relative_install = env['LIBDIR_SCHEMA'] + '/python' + env['PYTHON_VERSION'] + '/site-packages/'        
+        if env['PYTHON_PREFIX']:
+            env['PYTHON_INSTALL_LOCATION'] = env['DESTDIR'] + '/' + env['PYTHON_PREFIX'] + '/' +  py_relative_install
+        
+        # TODO...
+        # When the env['PREFIX'] is changed should that
+        # also affect/override where to install python?
+        # Perhaps env['PREFIX'] should be None by default
+        # while 'usr/local' would be overridden in the code if
+        # env['PREFIX'] is set?
+        # This way we could more easily check for a 'custom' PREFIX
+        
+        # code here but disabled...
+        #elif not env['PREFIX'] == '/usr/local':
+        #    env['PYTHON_INSTALL_LOCATION'] = env['DESTDIR'] + '/' + env['PREFIX'] + '/' +  py_relative_install        
+        
+        else:
+            env['PYTHON_INSTALL_LOCATION'] = env['DESTDIR'] + '/' + env['PYTHON_SITE_PACKAGES']
+           
         majver, minver = env['PYTHON_VERSION'].split('.')
     
         if (int(majver), int(minver)) < (2, 2):
             color_print(1,"Python version 2.2 or greater required")
             Exit(1)
     
-        color_print(4,'Python %s prefix... %s' % (env['PYTHON_VERSION'], env['PYTHON_PREFIX']))
+        color_print(4,'Bindings Python version... %s' % env['PYTHON_VERSION'])
+
+        color_print(4,'Python %s prefix... %s' % (env['PYTHON_VERSION'], env['PYTHON_SYS_PREFIX']))
+        
+        color_print(4,'Python bindings will install in... %s' % os.path.abspath(env['PYTHON_INSTALL_LOCATION']))
     
         SConscript('bindings/python/SConscript')
         

bindings/python/SConscript

@@ -30,9 +30,6 @@ if env['CAIRO'] and conf.CheckPKGConfig('0.15.0') and conf.CheckPKG('pycairo'):
     env.ParseConfig('pkg-config --cflags pycairo')
     env.Append(CXXFLAGS = '-DHAVE_PYCAIRO');
 
-prefix = env['PYTHON_PREFIX'] + '/' + env['LIBDIR_SCHEMA'] + '/python' + env['PYTHON_VERSION'] + '/site-packages/'
-install_prefix = env['DESTDIR'] + '/' + prefix
-
 linkflags = ''
 libraries = ['mapnik','png','jpeg']
 libraries.append('boost_python%s' % env['BOOST_APPEND'])
@@ -47,9 +44,7 @@ if env['PLATFORM'] == 'Darwin':
         libraries.append([lib for lib in env['LIBS'] if lib.startswith('cairo')])
     linkflags = '-F/ -framework Python'
 
-headers = [env['PYTHON_PREFIX'] + '/include/python' + env['PYTHON_VERSION']] + env['CPPPATH']
+headers = [env['PYTHON_INCLUDES']] + env['CPPPATH']
-
-_mapnik = env.LoadableModule('_mapnik', glob.glob('*.cpp'), LIBS=libraries, LDMODULEPREFIX='', LDMODULESUFFIX='.so', CPPPATH=headers,LINKFLAGS=linkflags)
 
 paths = """
 mapniklibpath = '%s'
@@ -57,13 +52,26 @@ inputpluginspath = mapniklibpath + '/input'
 fontscollectionpath = mapniklibpath + '/fonts'
 """
 
+# write out the location of the 'mapniklibpath' into a python file
+# so that the python module can located it at runtime
 exp =  r"%s{2,}" % os.sep
 mapnik_plugins_dir  = re.sub(exp,os.sep, env['PREFIX'] + '/'+env['LIBDIR_SCHEMA']+'/mapnik')
 file('mapnik/paths.py','w').write(paths % (mapnik_plugins_dir,))
 
-pymapnik = glob.glob('mapnik/*.py')
+# install the core mapnik python files, including '__init__.py' and 'paths.py'
-env.Alias(target='install', source=env.Install(install_prefix+'/mapnik', pymapnik))
+init_files = glob.glob('mapnik/*.py')
-pymapnik2 = glob.glob('mapnik/ogcserver/*.py')
+init_module = env.Install(env['PYTHON_INSTALL_LOCATION'] + '/mapnik', init_files)
-env.Alias(target='install', source=env.Install(install_prefix+'/mapnik/ogcserver', pymapnik2))
+env.Alias(target='install', source=init_module)
-pymapniklib = env.Install(install_prefix+'/mapnik',_mapnik)
+
-env.Alias(target="install",source=pymapniklib)
+# install the ogcserver module code
+ogcserver_files = glob.glob('mapnik/ogcserver/*.py')
+ogcserver_module = env.Install(env['PYTHON_INSTALL_LOCATION'] + '/mapnik/ogcserver', ogcserver_files)
+env.Alias(target='install', source=ogcserver_module)
+
+
+# install the shared object beside the module directory
+_mapnik = env.LoadableModule('_mapnik', glob.glob('*.cpp'), LIBS=libraries, LDMODULEPREFIX='', LDMODULESUFFIX='.so', CPPPATH=headers,LINKFLAGS=linkflags)
+pymapniklib = env.Install(env['PYTHON_INSTALL_LOCATION'] + '/mapnik',_mapnik)
+env.Alias(target='install',source=pymapniklib)
+
+#import pdb;pdb.set_trace()