Using Pyrex To Write Components

First stab at writing Kamaelia Components using Pyrex. This code uses Pyrex 0.9.3, and has some issues that need resolving, but this does actually work.

File: pyrexcomponent.pyx

#
# Simple pyrex component
#

import Axon.Component.component

cdef class test(Axon.Component.component):
def mainBody(self):
if self.dataReady("inbox"):
data = self.recv("inbox")
self.send(data, "outbox")
return 1

File: Axon.Component.pxd

class component:
pass

File: setup.py

from distutils.core import setup
from distutils.extension import Extension
from Pyrex.Distutils import build_ext

setup(
name = 'PyrexComponent',
ext_modules=list(
Extension("pyrexcomponent",
["pyrexcomponent.pyx"],
),
),
cmdclass = {'build_ext': build_ext}
)

Build

> sudo python setup.py install
Password:
running install
running build
running build_ext
building 'pyrexcomponent' extension
.../pyrex/Axon.Component.pxd:1:0: class definition not allowed here
.../pyrex/pyrexcomponent.pyx:7:5: 'component' is not declared
> sudo python setup.py install
running install
running build
running build_ext
building 'pyrexcomponent' extension
gcc -pthread -fno-strict-aliasing -DNDEBUG -O2 -march=i586 -mcpu=i686 -fmessage-length=0 -Wall -g -fPIC -I/usr/include/python2.4 -c
pyrexcomponent.c -o build/temp.linux-i686-2.4/pyrexcomponent.o
pyrexcomponent.c: In function `__pyx_tp_new_14pyrexcomponent_test':
pyrexcomponent.c:187: warning: unused variable `p'
pyrexcomponent.c: In function `__pyx_tp_dealloc_14pyrexcomponent_test':
pyrexcomponent.c:192: warning: unused variable `p'
pyrexcomponent.c: In function `__pyx_tp_traverse_14pyrexcomponent_test':
pyrexcomponent.c:197: warning: unused variable `e'
pyrexcomponent.c:198: warning: unused variable `p'
pyrexcomponent.c: In function `__pyx_tp_clear_14pyrexcomponent_test':
pyrexcomponent.c:203: warning: unused variable `p'
pyrexcomponent.c: At top level:
pyrexcomponent.c:12: warning: `__Pyx_UnpackItem' declared `static' but never defined
pyrexcomponent.c:13: warning: `__Pyx_EndUnpack' declared `static' but never defined
pyrexcomponent.c:14: warning: `__Pyx_PrintItem' declared `static' but never defined
pyrexcomponent.c:15: warning: `__Pyx_PrintNewline' declared `static' but never defined
pyrexcomponent.c:16: warning: `__Pyx_Raise' declared `static' but never defined
pyrexcomponent.c:17: warning: `__Pyx_ReRaise' declared `static' but never defined
pyrexcomponent.c:19: warning: `__Pyx_GetExcValue' declared `static' but never defined
pyrexcomponent.c:20: warning: `__Pyx_ArgTypeTest' declared `static' but never defined
pyrexcomponent.c:21: warning: `__Pyx_TypeTest' declared `static' but never defined
pyrexcomponent.c:22: warning: `__Pyx_GetStarArgs' declared `static' but never defined
pyrexcomponent.c:23: warning: `__Pyx_WriteUnraisable' declared `static' but never defined
pyrexcomponent.c:25: warning: `__Pyx_ImportType' declared `static' but never defined
pyrexcomponent.c:26: warning: `__Pyx_SetVtable' declared `static' but never defined
pyrexcomponent.c:27: warning: `__Pyx_GetVtable' declared `static' but never defined
pyrexcomponent.c:28: warning: `__Pyx_CreateClass' declared `static' but never defined
pyrexcomponent.c:31: warning: `__Pyx_GetName' declared `static' but never defined
gcc -pthread -shared build/temp.linux-i686-2.4/pyrexcomponent.o -o build/lib.linux-i686-2.4/pyrexcomponent.so
running install_lib
copying build/lib.linux-i686-2.4/pyrexcomponent.so -> /usr/lib/python2.4/site-packages

Creating an instance

> python
Python 2.4 (#1, Mar 22 2005, 21:42:42)
[GCC 3.3.5 20050117 (prerelease) (SUSE Linux)] on linux2
Type "help", "copyright", "credits" or "license" for more information.
>>> from Axon.Component import component
>>> import pyrexcomponent
Traceback (most recent call last):
File "<stdin>", line 1, in ?
File "pyrexcomponent.pyx", line 12, in pyrexcomponent
import Axon.Component.component
ImportError: No module named component
>>> import pyrexcomponent
>>> pyrexcomponent
<module 'pyrexcomponent' (built-in)>

>>> class foo(pyrexcomponent.test, component): pass
...
>>> x=foo()
>>> x
>>> component.__init__(x)
>>> x.inboxes
>>> x.mainBody
<built-in method mainBody of foo object at 0x404a4a04>
>>> x.mainBody.__doc__
>>> x.activate()
<__main__.foo object at 0x404a4a04>
>>> x.mainBody.__doc__
>>> x._deliver("hello")
>>> x._deliver("world")
>>> x.next()
1
>>> x.next()
1
>>> x.next()
1
>>> x._collect()
'hello'
>>> x._collect()
'world'

Summary

There's clearly some minor issues here and scope for improvement, but this clearly shows that you can write components in pyrex, which therefore means you can pull in any library with a C interface with relative ease.