GitHub - jnfeinstein/gortex: Text search for postgres w/ ORM in golang

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!