dotnet-publicsuffix-data

Wrapper around the Public Suffix List https://publicsuffix.org/.

The Public Suffix List is a community-maintained registry of top-level domains, meaning domains under which you can directly register names. For example, .org, .com, and .uk are top-level domains, so you can register an example.org, example.com, or example.uk domain. However, .co.uk, despite consisting of two tokens, is also a top-level domain, so you cannot register co.uk as a domain.

This is a .NET port of https://github.com/DullReferenceException/node-publicsuffix-data

Installing

To install GoDaddy.PublicSuffixData, run the following command in the Package Manager Console

PM> Install-Package GoDaddy.PublicSuffixData

Simple Usage

Using this is as simple as newing up an instance and calling GetTldAsync:

using GoDaddy.PublicSuffixData;

public class SampleClass
{
    public async Task SampleMethod()
    {
        var dataStore = new PublicSuffixDataStore();
        var tld = await dataStore.GetTldAsync("sample.co.uk");
        Assert.AreEqual(tld, "co.uk");    
    }
}

How it works

Obviously, we don't want to download this database on every request. This library relies on a series of caches. If the data is available in memory, that is used. Else, a file system cache is checked. Otherwise, the data is fetched from the Internet and cached in memory and on disk. Caches have two settings: timeToStale and timeToExpired. If data is stale, it will still be used, but a newer copy of the data is asynchronously fetched and cached. If the data is expired, we wait on the latest data to be fetched.

Custom Configuration

Out of the box, this library uses these default settings:

Setting	Value
url	https://publicsuffix.org/list/effective_tld_names.dat
fileCache	%APPDATA%\.publicsuffix.org
timeToStale	10 days
timeToExpired	30 days

To customize settings, there are two options. First off, you can add a configuration section to your application's web.config or app.config:

<configuration>
  <configSections>
    <section name="goDaddy.publicSuffixData" type="GoDaddy.PublicSuffixData.PublicSuffixDataConfigSection, GoDaddy.PublicSuffixData"/>
  </configSections>
  <goDaddy.publicSuffixData
    timeToStale="5.00:00:00"
    timeToExpired="10.00:00:00"
    url="http://other.url/"
    cacheFile="C:\Path\To\File.json"/>
</configuration>

Alternately, the PublicSuffixDataStore constructor can take an object implementing IPublicSuffixConfig.