How to read the properties file from perl script - perl

Question

I have written a perl script where I will be connecting to database, for which I'm using this statement
my $dbh = DBI->connect(
"DBI:mysql:database=test;host=localhost;mysql_socket=/var/run/mysqld/mysqld.sock",
"root", "password", {'RaiseError' => 1});
As I don't want any information to be hardcoded, I want to use properties file where I can list the above details (e.g., database, host, mysql_socket) and read the details of properties file from the script. How can I write the properties file and read the details from perl script?

Answer 1

There are a lot of CPAN modules that helps you to achieve this task.
I like Config::Simple, for example:
#!/usr/bin/perl
use strict;
use warnings;
use Config::Simple;
...
my $cfg = new Config::Simple('myapp.ini');
my $user = $cfg->param('database.user');
my $connection_str = $cfg->param('database.connection');
#...
and the file myapp.ini:
[database]
connection="DBI:mysql:database=test;host=localhost;mysql_socket=/var/run/mysqld/mysqld.sock"
user=root
;...
You can install the module from the terminal/command prompt using:
cpan install Config::Simple
or
yum install perl-Config-Simple

Answer 2

I had issues using perl-Config-Simple and decided to use Config::Properties instead. If you are experiencing the same, then you can try the following.
Make sure you have the Config::Properties installed. The following are several examples of how to install from command line, depending on the OS you are using, you'll want to use the appropriate choice:
cpan Config::Properties
cpan install Config::Properties
yum install perl-Config-Properties
The code:
#!/usr/bin/perl
use strict;
use warnings;
use Config::Properties;
open my $cfh, '<', './foo.properties' or die "unable to open property file";
my $properties = Config::Properties->new();
$properties->load($cfh);
my $dbName = $properties->getProperty('database.name');
my $dbUser = $properties->getProperty('database.user');
The property file:
database.name=somedb
database.user=someuser
Once you have the values in the variables, put them into your connection string and you should be good to go.

Answer 3

var temp;
if($ENV eq "Prod"){
#Prod Configurations
temp = "Prod";
}
else{
# Stage and Test Confgurations
temp = "Stage";
}

Answer 4

My brick and mortar solution, exports one value from a properties file:
#!/usr/bin/perl
use strict;
use warnings;
my $line;
foreach $line (<STDIN>) {
chomp($line);
if(my $match = $line =~ /^(.*)=(.*)$/){
my $key = $1;
my $value = $2;
if ($ARGV[0] eq $key) {
print "$value\n";
exit 0;
}
}
}
Usage: perl script.pl mykey < file.properties