Re: Patch for 9.1: initdb -C option

Top posting.  On purpose.  :p
This patch seems to be foundering in a sea of opinions.  It seems
that everybody wants to do *something* about this, but what?
For one more opinion, my shop has chosen to never touch the default
postgresql.conf file any more, beyond adding one line to the bottom
of it which is an include directive, to bring in our overrides.
What will make everyone happy here?
-Kevin
KaiGai Kohei <kaigai@ak.jp.nec.com> wrote:
> (2010/03/29 14:04), David Christensen wrote:
>> Enclosed is a patch to add a -C option to initdb to allow you to
>> easily append configuration directives to the generated
>> postgresql.conf file for use in programmatic generation.  In my
>> case, I'd been creating multiple db clusters with a script and
>> would have specific overrides that I needed to make.  This patch
>> fell out of the desire to make this a little cleaner.  
>> Please review and comment.
>> 
>>  From the commit message:
>> 
>>      This is a simple mechanism to allow you to provide explicit
>>      overrides to any GUC at initdb time.  As a basic example,
>>      consider the case where you are programmatically generating
>>      multiple db clusters in order to test various
>>      configurations:
>> 
>>        $ for cluster in 1 2 3 4 5 6;
>>        >    do initdb -D data$cluster -C "port = 1234$cluster" \
>>        >         -C 'max_connections = 10' -C shared_buffers=1M;
>>        >  done
>> 
>>      A possible future improvement would be to provide some basic
>>      formatting corrections to allow specificications such as -C
>>      'port 1234', -C port=1234, and -C 'port = 1234' to all be
>>      ultimately output as 'port = 1234' in the final output. 
>>      This would be consistent with postmaster's parsing.
>> 
>>      The -C flag was chosen to be a mnemonic for "config".
> I'd like to volunteer reviewing your patch at first in this commit
> fest.
> 
> We already had a few comments on the list before. I want to see
> your opinion for the suggestions prior to code reviews.
> 
> Itagaki-san suggested:
> | Why don't you use just "echo 'options' \
> |           >>$PGDATA/postgresql.conf" ?
> | Could you explain where the -C options is better than initdb +
> | echo?
> 
> Greg suggested:
> | We had a patch not quite make it for 9.0 that switched over the 
> | postgresql.conf file to make it easy to scan a whole directory
> | looking for configuration files:
> | 
http://archives.postgresql.org/message-id/9837222c0910240641p7d75e2a4u2cfa6c1b5e603d84@mail.gmail.com
> |
> | The idea there was to eventually reduce the amount of
> | postgresql.conf hacking that initdb and other tools have to do. 
> | Your patch would add more code into a path that I'd like to see
> | reduced significantly.
> |
> | That implementation would make something easy enough for your
> | use case too (below untested but show the general idea):
> |
> | $ for cluster in 1 2 3 4 5 6;
> |  do initdb -D data$cluster
> |  (
> |  cat <<EOF
> |  port = 1234$cluster;
> |  max_connections = 10;
> |  shared_buffers=1M;
> |  EOF
> |  ) > data$cluster/conf.d/99clustersetup
> | done
> |
> | This would actually work just fine for what you're doing right
> | now if you used ">> data$cluster/postgresql.conf" for that next
> | to last line there.  There would be duplicates, which I'm
> | guessing is what you wanted to avoid with this patch, but the
> | later values set for the parameters added to the end would win
> | and be the active ones.
> 
> Peter suggested: 
> | I like this idea, but please use small -c for consistency with
> | the postgres program.
> 
> It seems to me what Greg suggested is a recent trend. Additional 
> configurations within separated files enables to install/uninstall
> third-party plugins easily from the perspective of packagers,
> rather than consolidated configuration.
> 
> However, $PGDATA/postgresql.conf is created on initdb, so it does
> not belong to a certain package. I don't have certainty whether
> the recent trend is also suitable for us, or not.