Perl - Creating json object in perl for zabbix host.update api

Question

I am trying to call a zabbix api host.update by using JSON RPC module. $json variable

$json = {
    jsonrpc => '2.0',
    method  => 'host.update',
    params  => {
        hostid => "$host_id",    #  global variable from the first function host.get
        groups => [
            { groupid => "$arg1" },
            { groupid => "$arg2" },
            { groupid => "$arg3" },
        ],
    },
    id   => 2,
    auth => "$authID",
};

$response = $client->call( $url, $json );

This works fine. But issue is when we have a dynamic list of groupids. It cannot always be 3 groupids.

So i created an array of hash for groupids and also a hash variable to hold other information.

Eg

# @gid is an array of group ids

my @groups;    # this array will hold records of hash ie array of hash records

foreach my $id (@gid) {
    push( @groups, { groupid => $id } );
    # construct array of hash records of groupids
}

my $groupjson = encode_json( \@groups );

my %data = (
    jsonrpc => '2.0',
    method  => 'host.update',
    params  => { hostid => "@hid", groups => "$groupjson" },
    id      => 1,
    auth    => "$authID"
);

my $datajson = encode_json \%data;

$response = $client->call( $api_url, $datajson );

When i run the above code, i get the error "not a hash reference" for "groups"

Can any one pls assist me?

Answer 1

You can do all your json encoding in a single pass, like so:

# shortcut for creating an array of hashes
my @groups = map { { groupid => $_ } } @gid;

my %data = (
    jsonrpc => '2.0',
    method  => 'host.update',
    params  => {
        hostid => \@hid,
        groups => \@groups
    },
    id   => 1,
    auth => $authID
);

my $json = encode_json( \%data );

If you put data that is already a JSON string into your %data hash, it will get encoded twice!