From: "Ara.T.Howard" <Ara.T.Howard@...>
Date: 2005-09-10T00:13:16+09:00
Subject: Re: [ANN] acgi-0.0.0

On Fri, 9 Sep 2005, Tom Counsell wrote:

> Thank you for this Ara,
>
> On 7 Sep 2005, at 21:25, Ara.T.Howard wrote:
>>   this version is proof of concept only!!!  it's likely to run only on 
>> linux,
>>   though it may run on many *nix platforms.  or maybe not.  there is little 
>> to
>>   no error checking, the sun could explode if you run the example program.
>>   security is not considered.
>

> 1. I can confirm that your example script works on Mac OS X Tiger 10.4.2
> once the posixlock extension is installed.

great!

> 2. Do error messages caused by me miss-coding my cgi scripts go anywhere
> accessible when using acgi?

not yet.  if you look at index.c or alib.rb you'll see that only stdout is
currently processed.  stdin and stderr are essentially ignored.  this is
because i need to write someting portable that does the following in index.c:

   if stdin has data
     send it down the pipe
   end

   while data from stdout or stderr pipes
     relay stdout from pipe to stdout
     relay stderr from pipe to stderr
   end

and - in the ruby code - i need to add the following logic

   if stdin_pipe.has_data?
     redirect STDIN => stdin_pipe
   end

so http posts would work (which come in on stdin).  the ruby code is already
setup to deal with stderr (but c program is not).  basically i didn't want to
spend the time to do this portably if there wasn't any interest.

however - you don't have to fumble in the dark guessing if you're program
runs.  the way acgi.rb is setup only on instance of a servlet can run at once
and the c program will not attempt to spawn another if it finds one running.
therefore there is no harm in starting you cgi servelet from a terminal where
you can see all the stderr for yourself.  so could do something like the
following in a terminal.

   - just run at the terminal.  here stderr will appear on the console.  or, if
     your script has a syntax error - it won't even start:

     ~ > ruby ./server.rb </dev/null

   - run using a file full of key=value pairs for testing, letting stderr go to
     console.

     ~ > ruby ./server.rb <key_val.txt

   - just run at the terminal.  send stderr to a log.  view the log using tail:

     ~ > nohup ruby ./server.rb </dev/null 2>./server.log &

     ~ > tail -F ./server.log

obviously you need to kill any running instance of your servlet before doing
this or a new instance will refuse to start - so someting like

   ~ > ps -elf | grep server.rb

   ~ > kill -9 $pid


of course, for syntax errors, there is always 'ruby -c' too.


btw.  i forgot to add the benchmarks to the README, but on my box a cgi
running under acgi.rb is about 4/5 times faster (approx. 100 requests per
second) as compared to the same code written using plain ruby cgi (approx. 20
requests per second).  the server.cgi program included in the dist is the same
code as server.rb (the servlet) but meant to run as a cgi.  any chance you
could benchmark both using

   # profile acgi

     ~ > ab -n100 http://yourhost/path/index.cgi

   # profile normal cgi

     ~ > ab -n100 http://yourhost/path/server.cgi

and let me know the results?

kind regards.

-a
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