#!/usr/bin/env perl

use strict;
use warnings;
use Inca::Reporter::SimpleUnit;

my $BACKOFF_SECS = 30;
my $reporter = new Inca::Reporter::SimpleUnit(
  name => 'data.access.postgres.unit.connect',
  description => 'Tries to connect to postgres server and list databases',
  version => 8,
  unit_name => 'postgres connect'
);
$reporter->addArg('exec', 'postgres user account', 'psql');
$reporter->addArg('user', 'postgres user account', '');
$reporter->addArg('numTries', 'number of connect attempts before giving up', 5);
$reporter->processArgv(@ARGV);
my $user = $reporter->argValue( 'user' );
$user = "-U $user" if $user ne '';
my $psql = $reporter->argValue( 'exec' );
my $numTries = $reporter->argValue( 'numTries' );

my $success = 0;
my @output;
my $i;
for( $i = 0; $i < $numTries && ! $success; $i++ ) {
  sleep( $BACKOFF_SECS * $i ) if $? != 0;
  @output = $reporter->loggedCommand("$psql $user -l");
  $success = 1 if $? == 0;
}
$reporter->failPrintAndExit( "$psql $user -l failed after $i tries: @output $!" ) if $?;
if( ! grep(/List of databases/, @output) ) {
  $reporter->unitFailure( "Failed to list databases: @output" );
} else {
  shift @output; shift @output; shift @output; # trim off header (3 lines)
  my @dbnames = map( /^\s+(\S+)/, @output );
  $reporter->log( 'info', "databases found: " . join(", ", @dbnames) );
  $reporter->unitSuccess();
}
$reporter->print();

Click here to see help information for the data.access.postgres.unit.connect reporter.