How to unmarshall a json file with nested objects which can be different from eachother in Golang

With a json file that looks something like this, where someone can only have one social but it could be different depending on the person, how would I unmarshal this into a struct.

[
  {
    "name": "Bob",
    "age": 14,
    "occupation": "Builder",
    "social": {
        "facebook": "Bob_the_builder"
  },
  {
    "name": "Alice",
    "age": 14,
    "occupation": "Builder",
    "social": {
        "twitter": "Alice_the_builder"
  }
]

My current struct variables looks like this.

type User struct {
   Name String 'json:"name"'
   Age int 'json:"age"'
   Occupation String 'json:"occupation"'
   Social Social 'json:"social"'
}

type Social struct {
  Facebook String 'json:"facebook"'
  Twitter String 'json:"twitter"'
}

Is this the correct way to unmarshall the json or will it fail as the 'Social' struct wants two different strings one for Facebook and one for Twitter. Is there a better way to unmarshall a json like this?

The example you provided should work, it will just leave one of your strings empty.

If you want to replace Social with 2 different structs, you can make Social an interface which both new structs implement. Then use json.RawMessage to delay the unmarshalling of the json in social. This is the example given in the godocs:

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

func main() {
	type Color struct {
		Space string
		Point json.RawMessage // delay parsing until we know the color space
	}
	type RGB struct {
		R uint8
		G uint8
		B uint8
	}
	type YCbCr struct {
		Y  uint8
		Cb int8
		Cr int8
	}

	var j = []byte(`[
	{"Space": "YCbCr", "Point": {"Y": 255, "Cb": 0, "Cr": -10}},
	{"Space": "RGB",   "Point": {"R": 98, "G": 218, "B": 255}}
]`)
	var colors []Color
	err := json.Unmarshal(j, &colors)
	if err != nil {
		log.Fatalln("error:", err)
	}

	for _, c := range colors {
		var dst interface{}
		switch c.Space {
		case "RGB":
			dst = new(RGB)
		case "YCbCr":
			dst = new(YCbCr)
		}
		err := json.Unmarshal(c.Point, dst)
		if err != nil {
			log.Fatalln("error:", err)
		}
		fmt.Println(c.Space, dst)
	}
}

In this example they use a string to indicate as which struct to unmarshall Point. In your case you may need to first unmarshall social as map[string]interface{} and determine which type should be used based on the fields. Or add a socialType field to the User struct.