search

Documentation

Overview

Package search provides a way to index entities and run relatively complicated search queries, best served outside of data stores, and by specialized search engines like ElasticSearch or Solr etc.

This tackles the limitations caused by gocrud in terms of filtering and sort operations which would otherwise would need to be done at application level.

Index

• func Register(name string, driver Engine)
• type Engine
  • func Get() Engine
• type FilterQuery
• type Query

Functions

func Register

func Register(name string, driver Engine)

Types

type Engine

type Engine interface {
	// Init should be used for initializing search engine. The string arguments
	// can be used differently by different engines.
	Init(args ...string)

	// Update doc into index. Note that doc.NanoTs should be utilized to implement
	// any sort of versioning facility provided by the search engine, to avoid
	// overwriting a newer doc by an older doc.
	Update(x.Doc) error

	// NewQuery creates the query encapsulator, restricting results by given kind.
	NewQuery(kind string) Query
}

Engine provides the interface to be implemented to support search engines.

func Get

func Get() Engine

type FilterQuery

type FilterQuery interface {
	// AddExact would do exact full string, int, etc. filtering. Also called
	// term filtering by some engines.
	AddExact(field string, value interface{}) FilterQuery

	// AddRegex would do regular expression filtering.
	// Naturally, requires value to be string.
	AddRegex(field string, value string) FilterQuery
}

type Query

type Query interface {
	// NewAndFilter would return a filter which would run AND operation
	// among individual filter queries.
	NewAndFilter() FilterQuery

	// NewOrFilter would return a filter which would run OR operation
	// among individual filter queries.
	NewOrFilter() FilterQuery

	// From would set the offset from the first result. Use it along
	// with Limit(int) to do pagination.
	From(num int) Query

	// Limit would limit the number of results to num.
	Limit(num int) Query

	// Order would sort the results by field in ascending order.
	// A "-field" can be provided to sort results in descending order.
	Order(field string) Query

	// Run the generated query, providing resulting documents and error, if any.
	Run() ([]x.Doc, error)

	// Count the number of results that would be generated. Don't run the query.
	Count() (int64, error)
}

Query interface provides the search api encapsulator, responsible for generating the right query for the engine, and then running it.