If then else in json - json

Question

Set values based on the ip address in JSON with if the else
Using perl JSON module.
I'm trying to setup my etc/config.json so that I never have to edit it when I move code from development->staging->production.
sql ip addresses will be different for different VM's
{
"html_title" : "Bogus",
"local_ip" :
"default" : "[production]",
"hosts" :
{
"production" :
{
"10.11.12.13" : "b102-vm",
"10.11.12.14" : "b103-vm"
},
"stage" :
{
"10.11.12.15" : "b102-vm-s",
"10.11.12.16" : "b103-vm-s"
},
},
"production" :
{
"some_schema" :
{
"host" : "10.11.12.13",
"database" : "some_table",
"dsn" : "DBI:mysql:[production.some_schema.database]:[production.some_schema.host]",
"user" : "user",
"pass" : "pass"
}
},
"stage" :
{
"some_schema" :
{
"host" : "10.11.12.16",
"database" : "some_table",
"dsn" : "DBI:mysql:[stage.some_schema.database]:[stage.some_schema.host]",
"user" : "user",
"pass" : "pass"
}
},
"if" : HERE IS WHERE I GET LOST.
{
"local_ip" : {
"anyOf" : ["[hosts.production]"]
}
},
"then" : { "default" : "[production]" }
"else" :
{
"if" :
{
"local_ip" : {
"anyOf" : ["[hosts.stage]"]
}
},
"then" : { "default" : "[production]" }
}
}
Would like to see "default" point to the production or stage values

Answer 1

As others have pointed out in the comments, JSON is not a programming language; it is a data storage format.
I can think of two obvious ways to do this. Yours is, I'm sorry to say, not one of them.
Both of my solutions involve your various systems having an environment variable set which identifies the kind of environment it is. I'm also going to assume some kind of get_config() function that reads a config file and returns a Perl data structure of the config.
Solution 1: Separate files
Have two files called "staging.json" and "production.json". The get_config() function reads the required one.
sub get_config {
my %valid_env = (
staging => 1,
production => 1,
);
die "$ENV{ENVIRONMENT} is not a valid environment type\n"
unless $valid_env{$ENV{ENVIRONMENT}};
my $json = read_file("$ENV{ENVIRONMENT}.json");
return JSON->new->decode($json);
}
As an extension to this, you could have three files - common.json, staging.json and production.json. You'd always read common.json along with the correct environment file and merge the two data structures into one before returning the data.
Solution 2: Munge the config
Stick with your existing file but munge the data structure after you've read it and before you return it.
sub get_config {
my %valid_env = (
staging => 1,
production => 1,
);
die "$ENV{ENVIRONMENT} is not a valid environment type\n"
unless $valid_env{$ENV{ENVIRONMENT}};
my $json = read_file('config.json');
my $config = JSON->new->decode($json);
# Use $ENV{ENVIRONMENT} to munge the contents of $config
# so it only contains data about the current environment
return $config;
}