This document explains how to make Getdns extension for Ruby
- An installation of getdns 0.1.1 or later is required. Please see the https://github.com/getdnsapi/getdns GitHub.
- Install Ruby
- Then install bundler gem using command "gem install bundler". Bundler manages application dependencies and install into the gem library in your environment.
Note: Please checkout Ruby Version Manager (RVM) https://rvm.io/
In C, variables have types and data do not have types. Ruby is exactly opposite, Ruby variables do not have a static type but data themselves have types, so data will need to converted between languages.
Data in Ruby are represented by the C type `VALUE'. Each VALUE data has its data-type.
To retrieve C data from a VALUE, you need to:
- Identify the VALUE's data type
- Convert the VALUE into C data
Encapsulate a C struct as a Ruby object. There are two macros to do this wrapping, and one to retrieve your structure back out again.
- Data_Wrap_Struct: Take a C level pointer and shoves into a VALUE. Data_Wrap_Struct() returns a created DATA object.
- Data_Get_Struct: To retrieve the C pointer from the Data object, use the macro Data_Get_Struct(). Unwrap the ruby object as a data_type, and set data* to point to it.
#####Argument Checking
- rb_scan_args : It takes argc, argv, the number of required and optional arguments and pointers to the VALUE objects.
It will raise a Ruby exception when argument count is not as expected.
- VALUE foo;
- VALUE optional;
- rb_scan_args(argc, argv, "11", &foo, &optional);
- "11" tell rb_scan_args expect one required, one optional
rb_scan_args(argc, argv, "01", &optional); - "10" tell rb_scan_args expect one optional
getdns-ruby-bindings/
getdns.gemspec
Rakefile
ext/
getdns/
extconf.rb
*.cpp
lib/
getdns/
*.rb
test/
tc_*.rb
##Ruby binding for getdns ####getdns configuration
- Install all of the required gems using command - "bundle install"
$ rake build_ext
/usr/bin/ruby extconf.rb
checking for main() in -lgetdns... yes
checking for main() in -lunbound... yes
checking for main() in -lidn... yes
checking for main() in -lldns... yes
creating Makefile
make
linking shared-object getdns/getdns.so
cp ext/getdns/getdns.bundle lib/
- You can also execute "bundle install" after "rake build_ext"
#####From here on we can call getdns methods two ways 1.
-
After command 'rake build_ext'. cd /ext/getdns. To run all sync functions, async functions, options and extensions implementations:
ruby getdns.rb -
Run all sync functions, options and extensions tests:
rake test or ruby ts_getdns.rb -
Run particular sync functions, async function, options/extensions implementations:(Require library before executing the script)
ruby -r "./dns_transport_module.rb" -e "Dns_transport_module.dns_transport 'verisign.com'" -
Run particular option/extensions Test:
ruby -r "./tc_getdns_transport.rb" -e "Getdns_transport_option.new.test_getdns_transport_status 'verisign.com'"
steps to add this extension as gem.
$ gem build getdns.gemspec
Successfully built RubyGem
Name: getdns-ruby
Version: 0.0.1
File: getdns-ruby-0.0.1.gem
$ sudo gem install ./getdns-ruby-0.0.1.gem
Successfully installed getdns-ruby-0.0.1
Parsing documentation for getdns-ruby-0.0.1
Installing ri documentation for getdns-ruby-0.0.1
Done installing documentation for getdns-ruby after 0 seconds
1 gem installed
####Test gem and use: Check if getdns_ruby gem is installed properly
$ irb
>> require 'getdns_ruby'
=> true
>> ctx = Getdns::Context.new()
=> #<Getdns::Context:0x00000001a9d700>
>> ctx.lookup("verisign.com")
OR load gem directly using following command
irb -Ilib -rgetdns_ruby
Note: Load the ruby shell(irb) from directory lib/getdns for running sample code. There are couple of ways to play around with getdns-ruby gem.
- After gem installation testing load any file for test. For example load 'dns_transport_module.rb'
- Then invoke a method on a Ruby module
$ irb
>> load './dns_transport_module.rb'
=> true
>> Dns_transport_module.dns_transport('any domain name')
- Test code from .rb file
$ irb
>> require_relative '../../ext/getdns/getdns'
=> true
>> require_relative 'getdns_constants'
=> true
>> options = {
"timeout" => 10000,
"return_dnssec_status" => true,
"dns_transport" => GetdnsConstants::TRANSPORT_TCP_ONLY,
"stub" => true,
"upstreams" => ["8.8.8.8"],
}
=> {"timeout"=>10000, "return_dnssec_status"=>true, "dns_transport"=>542, "stub"=>true, "upstreams"=>["8.8.8.8"]}
>> ctx = Getdns::Context.new(options)
=> #<Getdns::Context:0x007ff4a9080e30>
>> x = ctx.lookup('verisign.com')
=> {"answer_type"=>800, "canonical_name"=>"verisign.com.", "just_address_answers"=>["69.58.181.89"], "replies_full"=>[[140688806169888], [140688806169968]],
"replies_tree"=>[{"additional"=>[], "answer"=>[{"class"=>1, "name"=>"verisign.com.", "rdata"=>{"ipv4_address"=>"E:\xB5Y", "rdata_raw"=>"E:\xB5Y"}, "ttl"=>17,
"type"=>1}], "answer_type"=>800, "authority"=>[], "canonical_name"=>"verisign.com.", "dnssec_status"=>403, "header"=>{"aa"=>0, "ad"=>0, "ancount"=>1,
"arcount"=>0, "cd"=>0, "id"=>27467, "nscount"=>0, "opcode"=>0, "qdcount"=>1, "qr"=>1, "ra"=>1, "rcode"=>0, "rd"=>1, "tc"=>0, "z"=>0},
"question"=>{"qclass"=>1, "qname"=>"verisign.com.", "qtype"=>1}}, {"additional"=>[], "answer"=>[],
"answer_type"=>800, "authority"=>[{"class"=>1, "name"=>"verisign.com.", "rdata"=>{"expire"=>3600, "mname"=>"a2.nstld.com.",
"rdata_raw"=>[140688806166784], "refresh"=>3600, "retry"=>1209600, "rname"=>"vshostmaster.verisign.com.", "serial"=>2011041162}, "ttl"=>738, "type"=>6}],
"canonical_name"=>"verisign.com.", "dnssec_status"=>403, "header"=>{"aa"=>0, "ad"=>0, "ancount"=>0, "arcount"=>0, "cd"=>0, "id"=>26773, "nscount"=>1,
"opcode"=>0, "qdcount"=>1, "qr"=>1, "ra"=>1, "rcode"=>0, "rd"=>1, "tc"=>0, "z"=>0}, "question"=>{"qclass"=>1, "qname"=>"verisign.com.", "qtype"=>28}}],
"status"=>900}