GORTEX

Text search for postgres w/ ORM using Golang

Overview

• Based on Textacular
• Utilizes gorm
• Creates scopes that, in conjunction with gorm, find records and scan them into Go structs
• Offers equivalent of Textacular advanced search
• Offers equivalent of Textacular fuzzy search
• You can even make your own types of search
• Generated scopes have no state so they can be used repeatedly

Example setup

import (
  "github.com/jnfeinstein/gorm"
  "github.com/jnfeinstein/gortex"
  _ "github.com/lib/pq"
)

type Note struct {
  Id       int64
  Contents string
  Author   string
}

DB, _ := gorm.Open("postgres", $POSTGRES_SRC)
DB.AutoMigrate(Note{})

var notes []Note

Normal search

Usage

gortex.NewSearchScope(clause interface{}, opts ...map[string]interface{})

Params

clause interface{} May be a struct or map[string]interface{} which specifies the fields and values to search

opts map[string]interface{} List of options which might include:

"language": string Specify language for search

"exclusive": bool Controls whether search fields should be AND'd or OR'd

Note: If clause is a struct, it will automatically set the table to the struct's type

Example

searchScope1 := gortex.NewSearchScope(Note{Contents: "brown"}, map[string]interface{}{"language": "english"})
DB.Scopes(searchScope1).Select("*").Find(&notes)
//// Finds all records with 'brown' in the contents field

searchScope2 := gortex.NewSearchScope(map[string]interface{}{"contents": "brown", "author": "dog"}, map[string]interface{}{"exclusive": false})
DB.Scopes(searchScope2).Select("*").Find(&notes)
//// Using 'simple' language, finds all records with 'brown' in the contents field OR 'dog' in the author field

Note: You must include .Select("*"), which instructs gorm to select all fields in addition to the search rankings

Fuzzy search

Usage

gortex.NewFuzzySearchScope(clause interface{}, opts ...map[string]interface{})

Params

clause interface{} May be a struct or map[string]interface{} which specifies the fields and values to search

opts map[string]interface{} List of options which might include:

"exclusive": bool Controls whether search fields should be AND'd or OR'd

Example

gortex.InitFuzzySearch(&DB) //// Creats pg_trgm extension
gortex.SetFuzzySearchLimit(&DB, limit) //// Optional, sets fuzzy search limit (default is 0.1)
//// Only need to be run once

searchScope3 := gortex.NewFuzzySearchScope(Note{Contents: "or"})
DB.Scopes(searchScope3).Select("*").Find(&notes)
//// Finds all records with something like 'or' in the contents, maybe 'organic' or 'boring'

Custom search (not for timid souls)

All gortex searches use a series of condition queries to determine qualification, and a series of select queries to determine rank. These queries are defined by the following interface:

type SearchSqlFormat interface {
  Rank(field string, opts map[string]interface{}) string
  Condition(field string, opts map[string]interface{}) string
}

SearchSqlFormat params

field string: Name of the field

opts map[string]interface{} The very same map passed into gortex.NewCustomSearchScope

Usage

gortex.NewCustomSearchScope(format SearchSqlFormat, clause interface{}, opts ...map[string]interface{})

Params

clause interface{} May be a struct or map[string]interface{} which specifies the fields and values to search

opts map[string]interface{} List of options which might include:

"exclusive": bool Controls whether search fields should be AND'd or OR'd

Example

type customSearchFormat struct{}

func (c customSearchFormat) Rank(field string, opts map[string]interface{}) string {
  return fmt.Sprintf("LENGTH(%s)", field)
}

func (c customSearchFormat) Condition(field string, opts map[string]interface{}) string {
  return fmt.Sprintf("%s LIKE ?", field)
}

searchScope4 := gortex.NewCustomSearchScope(customSearchFormat{}, Note{Author: "L%"})
DB.Scopes(searchScope4).Select("*").Find(&notes)
//// Finds all records with an author beginning with 'L' and ranks them by length of author

Indexing

Usage

gortex.AutoIndex(db *gorm.DB, language string, clause interface{}, table ...string)

Params

db *gorm.DB Instance of gorm.DB on which to add indexes (uses .Exec)

language string Postgres language to be indexed

clause interface{} May be a struct, string, or []string containing the fields to be indexed

table ...string Specifies the table to migrate if clause is a string or []string

Example

gortex.AutoIndex(&DB, "english", Note{})
//// Adds gin indexes idx_notes_content and idx_notes_author

gortex.AutoIndex(&DB, "english", "contents", "notes")
//// Adds gin index idx_notes_content

gortex.AutoIndex(&DB, "english", "contents", []string{"notes", "author"})
//// Adds gin indexes idx_notes_content and idx_notes_author

Note: This function is best-effort, and is not designed to be re-run. Therefore it will not return errors. You should verify the indexes manually if you care.

Contributing

Feel free to do so!