.NET Tokenizer

.NET Tokenizer is a library written in C# that extracts values from text. The library creates structured objects by overlaying patterns onto blocks of text.

##Installation

Installation:

Enter the following into the Package Manager Console window in Visual Studio:

Install-Package Tokenizer

##Basic Example

The Tokenizer library was originally developed in order to parse information from WHOIS records. A typical WHOIS record will contain free-form text such as the example below:

Domain Name: LATIMES.COM
Registry Domain ID: 510925_DOMAIN_COM-VRSN
Registrar WHOIS Server: whois.godaddy.com
Registrar URL: http://www.godaddy.com
Update Date: 2013-12-02 10:38:01
Creation Date: 1990-12-12 00:00:00
Registrar Registration Expiration Date: 2015-12-11 00:00:00
Registrar: GoDaddy.com, LLC
Registrar IANA ID: 146
Registrar Abuse Contact Email: [email protected]
Registrar Abuse Contact Phone: +1.480-624-2505
Registrant Name: TRIBUNE COMPANY
Registrant Organization: Tribune Technology LLC
Registrant Street: 435 N. Michigan Ave
Registrant City: Chicago
Registrant State/Province: Illinois
Registrant Postal Code: 60611
Registrant Country: United States
Registrant Phone: +1.3122229100
Registrant Email: [email protected]

The Tokenizer will create an object with the information from the text extract and set onto it's properties. A JSON representation of the information extracted from the above would be:

{
    "WhoisRecord": {
        "DomainName": "LATIMES.COM",
        "RegistryDomainId": "510925_DOMAIN_COM-VRSN",
        "Registrar": {
            "WhoisHostName": "whois.godaddy.com",
            "URL": "http://www.godaddy.com",
            "Name": "GoDaddy.com, LLC",
            "IanaId": "146"                
        },
        "CreatedDate": "1990-12-12",
        "ModifiedDate": "2013-12-03",
        "ExpirationDate": "2015-12-11",
        "AbuseEmail": "[email protected]",
        "AbusePhoneNumber": "+1.480-624-2505",
        "Registrant": {
            "Name": "TRIBUNE COMPANY",
            "Organization": "Tribune Technology LLC",
            "Street": "435 N. Michigan Ave",
            "City": "Chicago",
            "State": "Illinois",
            "PostalCode": "60611",
            "Country": "United States",
            "Phone": "+1.3122229100",
            "Email": "[email protected]",
        },
    }
}

The coding required to extract the information in the above example is simple. First create a simple class to hold all the information you'd like to extract from the source text:

public class WhoisRecord
{
    public string DomainName { get; set; }

    ...
}

In order to populate the class with values, create an instance of the Tokenizer and call the Parse() method. This instantiates a new object and parses the input text and reflects it's content onto the object. The TokenResult object contains a list of all tokens extracted, as well as a Value property with the new object assigned to.

public WhoisRecord Parse(string input)
{
    var tokenizer = new Tokenizer();

    var result = tokenizer.Parse<WhoisRecord>(pattern, input);

    return result.Value;
}

Before you can call the Tokenizer, you need to supply it with a pattern first. For the example above, the pattern would look something like:

Domain Name: #{WhoisRecord.DomainName}
Registry Domain ID: #{WhoisRecord.DomainId}
Registrar WHOIS Server: #{WhoisRecord.Registrar.WhoisHostName}
Registrar URL: #{WhoisRecord.Registrar.Url}
Updated Date: #{WhoisRecord.UpdatedDate}
Creation Date: #{WhoisRecord.CreatedDate}
Registrar Registration Expiration Date: #{WhoisRecord.ExpirationDate}
Registrar: #{WhoisRecord.Registrar.Name}
Registrar IANA ID: #{WhoisRecord.RegistrarIanaId}
Registrar Abuse Contact Email: #{WhoisRecord.AbuseEmail}
Registrar Abuse Contact Phone: #{WhoisRecord.AbusePhoneNumber}
Registrant Name: #{WhoisRecord.Registrant.Name}
Registrant Organization: #{WhoisRecord.Registrant.Organization}
Registrant Street: #{WhoisRecord.Registrant.Street}
Registrant City: #{WhoisRecord.Registrant.City}
Registrant State/Province: #{WhoisRecord.Registrant.State}
Registrant Postal Code: #{WhoisRecord.Registrant.PostalCode}
Registrant Country: #{WhoisRecord.Registrant.Country}
Registrant Phone: #{WhoisRecord.Registrant.PhoneNumber}
Registrant Email: #{WhoisRecord.Registrant.Email}

Each placeholder in the pattern refers to a property on the object. The library will walk the object graph, instantiating properties as it encounters them, to set the values specified in the placeholder.

Transforming Input

Sometimes the data you're processing requires preprocessing before it can be mapped onto your object. The Tokenizer library contains a number of built-in functions that enable this to save writing additional code.

Transforming Dates

Sometimes a dates in input text can't automatically be parsed by the .NET framework. In this case, you can add a ToDateTime() transform to tell the Tokenizer to parse the date in an exact format:

Creation Date: 4 Dec 1990 14:32

Pattern with transform:

Creation Date: #{WhoisRecord.CreationDate:ToDateTime('d MMM yyyy HH:mm')}

Limitations

The Tokenizer currently works on line-by-line. You cannot currently write multi-line placeholders.

Extending Tokenizer

The Tokenizer is easily extensible by adding new Token Operators and Token Validators.