On Mon, 10 Nov 2003, David W. Forslund wrote: ... > > Both statements above are not true: 1) Zope can send back any kind of > > file. 2) Web browsers know what to do with many non-HTML files (e.g. plain > > text, gif, jpg, etc). > > > 1) isn't what I said I said I invoked the object and that is what I > observe it returns. How do I tell it to return something different?
Dave, How can the client tell the server what it likes to see? Send a request. ... > SO I write client code by probing a server and seeing what it answers > with, rather than having a place where I can ask what it wants? With Zope, you can "ask" the server what it needs to process the request. I implemented something like that here: http://www.txoutcome.org/scripts/zope/readings/zsvg_graph_site/graph_me This method gives the required parameter list if the arguments are missing. > One is much more efficient than the other. It is debatable which one is more efficient. :-) ... > > I don't think there is any disagreement on this point. However, there are > > many ways to document, negotiate, and transact according to this > > "agreement". Perhaps CORBA and Java have a more elaborate and rigid way of > > doing this - but that does not mean it is more suitable or more useful for > > application development. > I can write a CORBA client that completely configures itself based on > the data types coming back. Not very "rigid". CORBA/Java is more rigid in the way that the documentation must be produced (e.g. via IDL, type declarations). I can also write a Zope client that completely configures itself based on the data that come back. > It can, in fact, discover the data type coming back rather than having > to "guess". Same with Zope. ... > > "legitimate" interface description language. For example, I showed an > > HTML form as the "interface description" for adding a sub-folder into the > > OIO Library. :-) > > > Is this a standard way that is available for any Zope object? Any Zope object can have an associated web-form. ... > > That's not true. You can embed processing instructions (even Java code) in > > the response. > How do I know it is Java code? Annotate the code block with a java tag? ... > > Right. That's why we have "previous calls". It does not matter whether we > > are using CORBA, Java, Zope, PHP, or C, either the client acts on > > assumptions or the server needs to send info to the client on the > > [previous, same, or future] call. > > > Perhaps, but I don't need that to make a DNS or LDAP call. I understand > the semantics and ack on them There exists some semantics that remain to be defined. Communication requires the ability to transmit novel concepts based on new semantics. ... > > I disagree. HTML happens to be a nice standard that the Mozilla web > > browser renders adequately. > > > But HTML doesn't tell me what any of these things "are". These things "are" to be displayed as tables, cells, paragraphs, etc. Send the right request to the right place and you may get the right response. How is that any different in CORBA/Java? ... > > No, send anything you like - send an XML document between Zope servers. > > How do I know what the meaning of the terms in the XML are without > having some external standard? But we do have external standards. All XML tags rely on accepted written human language. Best regards, Andrew --- Andrew P. Ho, M.D. OIO: Open Infrastructure for Outcomes www.TxOutcome.Org
