reddo

consu/reddo

Package reddo provides utility functions to convert values using Golang's reflection.

Installation

$ go get -u github.com/btnguyen2k/consu/reddo

Usage

package main

import (
	"fmt"
	"reflect"
	
	"github.com/btnguyen2k/consu/reddo"
)

type Abc struct {
	A int
}

type Def struct {
	Abc
	D string
}

// convenient method to get value and discarding error
func getValue(data map[string]interface{}, field string, typ reflect.Type) interface{} {
	v, err := reddo.Convert(data[field], typ)
	if err != nil {
		panic(err)
	}
	return v
}

func main() {
	// let's build a 'generic' key-value data store
	data := map[string]interface{}{}
	data["id"] = "1"
	data["name"] = "Thanh Nguyen"
	data["year"] = 2019
	data["abc"] = Abc{A: 103}
	data["def"] = Def{Abc: Abc{A: 1981}, D: "btnguyen2k"}

	// data["id"] and data["year"] both have type interface{}, we would want the correct type
	var id = getValue(data, "id", reddo.TypeString).(string)
	var year = getValue(data, "year", reddo.TypeInt).(int64)
	var yearUint = getValue(data, "year", reddo.TypeUint).(uint64)
	fmt.Printf("Id is %s, year is %d (%d)\n", id, year, yearUint) // Id is 1, year is 2019 (2019) 

	typeAbc := reflect.TypeOf(Abc{})
	typeDef := reflect.TypeOf(Def{})
	var abc = getValue(data, "abc", typeAbc).(Abc)
	var def = getValue(data, "def", typeDef).(Def)
	// special case: struct Def 'inherit' struct Abc, hence Def can be 'cast'-ed to Abc
	var abc2 = getValue(data, "def", typeAbc).(Abc)
	fmt.Println("data.abc       :", abc)  // data.abc       : {103}
	fmt.Println("data.def       :", def)  // data.def       : {{1981} btnguyen2k}
	fmt.Println("data.def as abc:", abc2) // data.def as abc: {1981}
	
	// special case: convert value to 'time.Time'
	v,_ := reddo.ToTime(1547549353)
	fmt.Println(v) // 2019-01-15 17:49:13 +0700 +07
	v,_ = reddo.ToTime("1547549353123")
	fmt.Println(v) // 2019-01-15 17:49:13.123 +0700 +07
}

License

This project is licensed under the MIT License - see the LICENSE.md file for details.

Support and Contribution

Feel free to create pull requests or issues to report bugs or suggest new features. Please search the existing issues before filing new issues to avoid duplicates. For new issues, file your bug or feature request as a new issue.

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