Post Processors

Reason

A post processor service is a type that configured in a SearchContext will process a collection of ResultInfo producing a new one. It's a class of type PostProcessor that must override the following abstract method:

IEnumerable<ResultInfo> Process(IEnumerable<ResultInfo> results)

It's also mandatory to define a constructor that accepts a single object parameter, used for the settings of the specific post processor.

Built-In

PickAll comes with following built-in post processors, that chan be found in PickAll.PostProcessors namespace:

• Uniqueness: removes duplicate results by URL
• Order: orders results placing indexes of same number close by each other
• FuzzyMatch: compares a string against results descriptions
• Improve: improves results computing word frequency to perform a subsequent search
• Wordify: reduces documents identified by results URLs to a collection of words

FuzzyMatch

FuzzyMatch post processors computes (Levenshtein Distance)[https://en.wikipedia.org/wiki/Levenshtein_distance] between a given string and results descriptions. If the distance is out of the specified range, the result will be excluded. Is configured as follows:

var context = SearchContext.Default
                    .With<FuzzyMatch>(new FuzzyMatchSettings {
                        Text = options.FuzzyMatch,
                        MaximumDistance = 10 }); // MinimumDistance default is 0