[TransWarp] peak.binding questions

Ulrich Eck ueck at net-labs.de
Wed Jun 4 12:55:36 EDT 2003

Hi Phillip,

while i have done lots of coding with peak during the last weeks
the following problem occured regularly and i don't know
how to "peak"ish solve it:

- I have different Implementations of something (e.g.
  platform-dependent) i specify them in my package-ini:

variantA = importString('some.path.to:A')
variantB = importString('some.path.to:B')

- then i have some Component where i want to use *one*
  of those variants. i also specify the choice in some
  user-conf(ini) file:

wichVariant = 'variantA'

the user-conf file should be as easy as possible e.g. no
cryptic config.getProperty(propertyMap ........)

initially i thought i could write something like this to create
an instance of some.path.to.A:

class MyImpl(binding.Component):

    myVariantInstance = binding.New( \
                        PropertyName('some.property.' + \

this obviously does not work as getProperty has ctx as first
parameter and is not known at that time. and New only accepts
strings or types/classes.

within the component i end up with once methods that do the
property lookups and create the instance by hand.

is there an easier way to do this?

same applies when i wanna configure some e.g. LDAPConnection:

i want to specify it in a config-file:

ldapurl = 'ldap://user:auth@server/base'

but i cannot say:

class MyDBComponent(binding.Base):

    connection = \

if these situations could be solved without writing once-methods
my could would look much better.

thanks for your comments



Ulrich Eck
net-labs Systemhaus GmbH
Ebersberger Str. 46
85570 Markt Schwaben - Germany

eMail: ueck <at> net-labs.de
phone: +49 8121 4747 10
fax:   +49 8121 4747 77

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