Test logstash filter with an input file

log-type.conf

# test.conf

input {
        file {
                path => "/tmp/some-file.log"
                start_position => beginning
                sincedb_path => "/dev/null"
                type => "some-type"
        }
}

filter {
    # Handles unprocessed entries
    if [type] == "some-type" {

        if "processed" not in [tags] {
            add_tag => [ "processed" ]
        }
    }
}

output {
    stdout { codec => json }
}

# validate
/usr/share/logstash/bin/logstash --path.settings /etc/logstash -f /tmp/test.conf --debug -t

# run
/usr/share/logstash/bin/logstash --path.settings /etc/logstash -f /tmp/test.conf --debug