zero backends return an error using the replication-topo branch

[fmpwizard]

If you use a dot file like this one

digraph proxydb
    {
       node[ class=proxy, "log-level"=message, "proxy.proxy-lua-script"="/Users/wizard/etools/mysql-lua-scripts/trunk/scripts/proxydb.lua" ];

       proxy1;
    }

You get this error "unable to read/parse /proxydb.dot" when running ./bin/make_sandbox_topology

If you add at least one slave, it works fine.

================

Details: This is using Oldag's branch.

revno: 22
committer: Darren L. Oldag <email address hidden>
branch nick: OldagSandbox
timestamp: Fri 2009-05-08 09:22:36 -0500
message:
  add some error checking so a bad dot/graph file
  does not contine and wipe out all your sandboxes.

Command was:

$ PROXY_HOME=/Applications/mysql/enterprise/2.1/mysql-proxy-0.7.0.0-osx10.5-x86-64bit ./bin/make_sandbox_topology 5132 /Users/wizard/Desktop/work/proxydb.dot

(I couldn't find a way to report a bug on just the topology branch :( )

[Oldag (oldag)]

this appears to be a bug in the underlying Graph::Reader::Dot parser. though your dot is valid (graphviz can parse it), the perl graph parser chokes on it.

without a fix to that, or moving to our own dot parser (i've found bugs in several others i've tried), the best we can do is workaround it.

try changing

proxy1;

to

proxy1[class=proxy];

while this shouldn't be necessary, it does seem to work around the parser problem.