searchInArray.go

// Loop through a map array to find the item matching by any of its keys/values
// In this example:
// [0]:
//     "fruta": "manzana",
//     "verdura": "coliflor"
// [1]:
//     "planas": "lentejas",
//     "redondas": "garbanzos"
// searching for "planas": "lentejas" yields array item [1]
//

package main

import (
	"encoding/json"
	"fmt"
	"reflect"
)

func myDebug(s string, i interface{}) {
	pretty, err := json.MarshalIndent(i, "", "  ")
	if err != nil {
		fmt.Println("error:", err)
	}
	fmt.Printf("\n\nmyDebug: %s (%s) => %s\n", s, reflect.TypeOf(i).String(), string(pretty))

	fmt.Printf("\n\nmyDebugPlain: %+v\n", i)
}

type Map map[string]interface{}

/**
 * Devuelve el elemento de un array cuyo campo indicado tiene el valor tambien indicado.
 */
func searchInArray(theArray []Map, key string, value string) Map {
	for i := range theArray {
		if theArray[i][key] == value {
			return theArray[i]
		}
	}

	return Map{}
}

func main() {
	mapas := make([]Map, 2)

	/*
		myDebug("mapas0", mapas[0])
		mapas[0] = make(Map)
		myDebug("mapas0", mapas[0])

			myDebug: mapas0 (main.Map) => null
			myDebugPlain: map[]
			myDebug: mapas0 (main.Map) => {}
			myDebugPlain: map[]
	*/

	// mapas = append(mapas, Map{})
	mapas[0] = make(Map)
	mapas[0]["fruta"] = "manzana"
	mapas[0]["verdura"] = "coliflor"

	// mapas = append(mapas, Map{})
	mapas[1] = make(Map)
	mapas[1]["planas"] = "lentejas"
	mapas[1]["redondas"] = "garbanzos"

	myDebug("mapas", mapas)
	/*
		myDebug: mapas ([]main.Map) => [
			{
				"fruta": "manzana",
				"verdura": "coliflor"
			},
			{
				"planas": "lentejas",
				"redondas": "garbanzos"
			}
		]
		myDebugPlain: [map[fruta:manzana verdura:coliflor] map[planas:lentejas redondas:garbanzos]]
	*/

	var result interface{}

	result = searchInArray(mapas, "planas", "lentejas")
	myDebug("result", result)

	result = searchInArray(mapas, "redondas", "lentejas")
	myDebug("result", result)

	result = searchInArray(mapas, "redondas", "garbanzos")
	myDebug("result", result)
}