[Openstreetmap] pop goes the segment

Lars Aronsson lars at aronsson.se
Mon Dec 5 10:14:22 GMT 2005

nick at hogweed.org wrote:

> I've noticed something similar.... I'm uploading segments (or 
> rather changing their tags) using osm-editor and sometimes I 
> don't get a response to the API call (which causes osmeditor to 
> hang... part of a major overhaul will be better error 
> checking...). I guess it must be a database issue.

In sufficiently complex software systems, I've found 
subject-oriented (rather than object-oriented) programming to be 
of great value.  If you're a client programmer, make your client 
act like a subject, speaking error messages in terms of "I" and 
"me", trying to cover its own ass, putting blame on other parts of 
the system.  For example: "At 10:57:05 I, the editor client, sent 
this call to the server and at 10:57:35 (30 seconds later), that 
stupid server still hasn't responded."  Then it is up to the 
server to cover its own reputation by providing an even more 
detailed log of who's to blame.  It's a code war, your program 
against mine shooting blame on each other.  Of course the programs 
should not log everything they do.  This should only happen when 
there is a chance that someone will try to put blame on them, e.g. 
when responses aren't issued within a reasonable time after a 

The server apparently can keep count of how many requests it 
receives and what the average response time is.  What if there was 
an API call to query this information.  The Java applet could 
display these numbers next to the tool bar.  On 
http://runeberg.org/rc.pl I display the unix server's uptime and 
load average at the top of the page.

  Lars Aronsson (lars at aronsson.se)
  Aronsson Datateknik - http://aronsson.se

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