On Thu, 28 Aug 2003, David Forslund wrote:
...
> callable_from_URL doesn't necessarily help in interoperability.
Dave,
After giving it some more thought, I am wondering whether
callable_from_URL can serve the same role for networked machines as the
"command line" did for individual machines?
Callable_from_URL does not guarantee interoperability, neither does the
command line interface. However, a simple interface through which
applications can be invoked is an important foundation on which UNIX-like
systems built "interoperable" applications. I noticed this similarity when
I programmed the help screen that gets displayed when the ZSVG_Graph's
"graph_me" method did not receive the required parameters.
This is idea is most likely not novel or revolutionary, but maybe it can
help us move forward in this discussion?
> There are almost no constraints involved there that will help with
> interoperability other than not caring what the language is.
With the command line interface (CLI), the implementation details of the
called application is similarly irrelevant. So, the importance of this
characteristic should not be under-estimated.
...
> Certainly, but this is what things like "Design by Contract" deal with
> and why one has to understand the side effects of a call and constrain
> the random user from doing something malicious.
...
> It is why things like "strong typing" and other constraining mechanisms
> help.
How is this any different for applications running on a single machine?
Did we need "Design by Contract" and "strong typing" to make "grep" work
with "mv"?
I am not saying that "Design by Contract" and "typing" are not helpful -
but 1) I don't think they are necessary for interoperability and
2) a simple, common calling convention is necessary.
...
> > > But has poor security management.
> >
> >Could you support this assertion with more information, references, or
> >examples?
>
> You need to know who is making the UR_call to decide whether you want to
> honor it. This may be difficult unless you are adding something else to
> the mix. At least https with full authentication.
I agree.
...
> >Why would it be harder to ensure availability of a "URL_callable"
> >application? "URL_callable" is just an application interface (ok, it
> >implies transport via http too).
>
> You said you wanted to rely on someone else's service on the Internet.
Actually, "URL_callable" does not mean "Internet". It is just an interface
for invoking an application.
...
> Reliable networks are required. I don't think this has anything to do with
> R&D.
If we are talking about remote invocation of programs, then reliable
network will always help availability. Whether a program is "URL_callable"
has nothing to do with this.
...
> I don't see the superior usability. I think it is a familiarity thing.
fine, but if more people/developers can become familiar with using the URL
to call a program, then this "familiarity thing" turns into a huge
"superior usability" perception! :-)
Best regards,
Andrew
---
Andrew P. Ho, M.D.
OIO: Open Infrastructure for Outcomes
www.TxOutcome.Org
