# Ruby DnsMock
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[](https://rubygems.org/gems/dns_mock)
[](LICENSE.txt)
[](CODE_OF_CONDUCT.md)
💎 Ruby DNS mock. Mimic any DNS records for your test environment and even more.
## Table of Contents
- [Features](#features)
- [Requirements](#requirements)
- [Installation](#installation)
- [Usage](#usage)
- [RSpec](#rspec)
- [Contributing](#contributing)
- [License](#license)
- [Code of Conduct](#code-of-conduct)
- [Credits](#credits)
- [Versioning](#versioning)
- [Changelog](CHANGELOG.md)
## Features
- Ability to mimic any DNS records (`A`, `AAAA`, `CNAME`, `MX`, `NS`, `PTR`, `SOA` and `TXT`)
- Zero runtime dependencies
- Lightweight UDP DNS mock server with dynamic/manual port assignment
- Test framework agnostic (it's PORO, so you can use it outside of `RSpec`, `Test::Unit` or `MiniTest`)
- Simple and intuitive DSL
## Requirements
Ruby MRI 2.5.0+
## Installation
Add this line to your application's `Gemfile`:
```ruby
group :development, :test do
gem 'dns_mock', require: false
end
```
And then execute:
$ bundle
Or install it yourself as:
$ gem install dns_mock
## Usage
```ruby
# Example of mocked DNS records, please follow this data structure
records = {
'example.com' => {
a: %w[1.1.1.1 2.2.2.2],
aaaa: %w[2a00:1450:4001:81e::200e],
ns: %w[ns1.domain.com ns2.domain.com],
mx: %w[mx1.domain.com mx2.domain.com:50], # you can specify host(s) or host(s) with priority
txt: %w[txt_record_1 txt_record_2],
cname: 'some.domain.com',
soa: [
{
mname: 'dns1.domain.com',
rname: 'dns2.domain.com',
serial: 2_035_971_683,
refresh: 10_000,
retry: 2_400,
expire: 604_800,
minimum: 3_600
}
]
},
'1.2.3.4' => {
ptr: %w[domain_1.com domain_2.com]
}
}
# Main DnsMock interface
# records:Hash, port:Integer, exception_if_not_found:Boolean
# are optional params. By default creates dns mock server with
# empty records. A free port for server will be randomly assigned
# in the range from 49152 to 65535, if record not found exception
# won't raises. Returns current dns mock server
dns_mock_server = DnsMock.start_server(records: records) # => DnsMock::Server instance
# returns current dns mock server port
dns_mock_server.port # => 49322
# interface to setup mock records.
# Available only in case when server mocked records is empty
dns_mock_server.assign_mocks(records) # => true/nil
# interface to reset current mocked records
dns_mock_server.reset_mocks! # => true
# interface to stop current dns mock server
dns_mock_server.stop! # => true
# returns list of running dns mock servers
DnsMock.running_servers # => [DnsMock::Server instance]
# interface to stop all running dns mock servers
DnsMock.stop_running_servers! # => true
```
### RSpec
Require this either in your Gemfile or in RSpec's support scripts. So either:
```ruby
# Gemfile
group :test do
gem 'rspec'
gem 'dns_mock', require: 'dns_mock/test_framework/rspec'
end
```
or
```ruby
# spec/support/config/dns_mock.rb
require 'dns_mock/test_framework/rspec'
```
#### DnsMock RSpec helper
Just add `DnsMock::TestFramework::RSpec::Helper` if you wanna use shortcut `dns_mock_server` for DnsMock server instance into your `RSpec.describe` blocks:
```ruby
# spec/support/config/dns_mock.rb
RSpec.configure do |config|
config.include DnsMock::TestFramework::RSpec::Helper
end
```
```ruby
# your awesome first_a_record_spec.rb
RSpec.describe FirstARecord do
subject(:service) do
described_class.call(
hostname,
dns_gateway_host: 'localhost',
dns_gateway_port: dns_mock_server.port
)
end
let(:hostname) { 'example.com' }
let(:first_a_record) { '1.2.3.4' }
let(:records) { { hostname => { a: [first_a_record] } } }
before { dns_mock_server.assign_mocks(records) }
it { is_expected.to eq(first_a_record) }
end
```
#### DnsMock RSpec interface
If you won't use `DnsMock::TestFramework::RSpec::Helper` you can use `DnsMock::TestFramework::RSpec::Interface` directly instead:
```ruby
DnsMock::TestFramework::RSpec::Interface.start_server # creates and runs DnsMock server instance
DnsMock::TestFramework::RSpec::Interface.stop_server! # stops current DnsMock server instance
DnsMock::TestFramework::RSpec::Interface.reset_mocks! # resets mocks in current DnsMock server instance
DnsMock::TestFramework::RSpec::Interface.clear_server! # stops and clears current DnsMock server instance
```
## Contributing
Bug reports and pull requests are welcome on GitHub at https://github.com/mocktools/ruby-dns-mock. This project is intended to be a safe, welcoming space for collaboration, and contributors are expected to adhere to the [Contributor Covenant](http://contributor-covenant.org) code of conduct. Please check the [open tikets](https://github.com/mocktools/ruby-dns-mock/issues). Be shure to follow Contributor Code of Conduct below and our [Contributing Guidelines](CONTRIBUTING.md).
## License
The gem is available as open source under the terms of the [MIT License](https://opensource.org/licenses/MIT).
## Code of Conduct
Everyone interacting in the DnsMock project’s codebases, issue trackers, chat rooms and mailing lists is expected to follow the [code of conduct](CODE_OF_CONDUCT.md).
## Credits
- [The Contributors](https://github.com/mocktools/ruby-dns-mock/graphs/contributors) for code and awesome suggestions
- [The Stargazers](https://github.com/mocktools/ruby-dns-mock/stargazers) for showing their support
## Versioning
DnsMock uses [Semantic Versioning 2.0.0](https://semver.org)