xmlrpc frustration

[Joe Van Dyk]

argh

% cat server.rb
require 'xmlrpc/server'

class ClusterManager
def start_application args
p args
return "ok"
end
end

server =3D XMLRPC::Server.new 1998, `hostname`.strip
server.add_handler "ClusterManager", ClusterManager.new
server.serve


% cat test.rb
require 'xmlrpc/client'

client =3D XMLRPC::Client.new "fatire", nil, 1998

begin
puts client.call "ClusterManager.start_application", "oogie boogie woogie=
"
rescue XMLRPC::FaultException =3D> e
p e
p e.faultCode
p e.faultString
end


% ruby test.rb
/usr/local/lib/ruby/1.8/xmlrpc/client.rb:535:in `do_rpc': HTTP-Error:
500 Internal Server Error (RuntimeError)
from /usr/local/lib/ruby/1.8/xmlrpc/client.rb:409:in `call2'
from /usr/local/lib/ruby/1.8/xmlrpc/client.rb:399:in `call'
from test.rb:7

What's up with the 500 Internal Server Error?
(btw, "oogie boogie woogie" printed in the server output).

 

[Tom Copeland]

argh

% cat server.rb
require 'xmlrpc/server'

class ClusterManager
def start_application args
p args
return "ok"
end
end

server = XMLRPC::Server.new 1998, `hostname`.strip
server.add_handler "ClusterManager", ClusterManager.new
server.serve

Hi Joe -

Hey, I'm doing some XMLRPC things at the moment too. When I run your
test server and client I get:

==============
$ ruby client.rb
client.rb:6: warning: parenthesize argument(s) for future version
ok
==============

Yours,

Tom

 

[Warren Seltzer]

There appear to be 2 separate exception mechanisms in Ruby, catch/throw and
rescue/raise/retry. Is this right?

Warren Seltzer

 

[Alexandru Popescu]

I haven't met/read about catch/throw. The begin/rescue/ensure/end is
for sure ;-).

/alex

 

[Edward Faulkner]

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There appear to be 2 separate exception mechanisms in Ruby, catch/throw a= nd
rescue/raise/retry. Is this right?

Yes, but they're not used for the same thing. =20

rescue/raise is used to signal error conditions. This is analogous to
Exceptions in Java or C++.

Throw/catch is used to unwind the stack to a desired point. It's like
a labeled break. For example:

catchdone){
loop {
do_work
if time_to_stop? throw :done
}
}

It's nice because you can break out of arbitrarily nested loops/blocks/etc.

regards,
Ed

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[Kirk Haines]

There appear to be 2 separate exception mechanisms in Ruby, catch/throw and
rescue/raise/retry. Is this right?

Not really. A throw just lets one unwind from some deep nesting without
generating a back trace, passing some value along to the catch.

It is much faster and lighter weight than the exception mechanism, and should
be used for cases where a fast, lightweight escape from some deep place is
wanted, perhaps with some passing of data from the deep place to the shallow
place, but where an actual exception isn't needed.


Kirk Haines

 

[Robert Klemme]

Yes, but they're not used for the same thing.

rescue/raise is used to signal error conditions. This is analogous to
Exceptions in Java or C++.

Throw/catch is used to unwind the stack to a desired point. It's like
a labeled break. For example:

catchdone){
loop {
do_work
if time_to_stop? throw :done
}
}

You probably meant

catchdone){
loop {
do_work
throw :done if time_to_stop?
}
}

It's nice because you can break out of arbitrarily nested

loops/blocks/etc.

Plus you can return something from the throw like this:

catchdone){
loop {
do_work
throw :done, "result" if time_to_stop?
}
}

Kind regards

robert