How to Fix Error: unexpected end of JSON input in Go

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The Error: unexpected end of json input occurs when the “JSON being parsed is either empty or truncated.”

To fix the Error: unexpected end of json input in Go, ensure the JSON input is complete and well-formed.

package main

import (
  "encoding/json"
  "fmt"
)

type Student struct {
  Name string `json:"name"`
  Age int `json:"age"`
}

func main() {
  var s Student
  jsonData := `{"name":"Krunal", "age": 30`

  err := json.Unmarshal([]byte(jsonData), &s)
  if err != nil {
    fmt.Println("Error:", err)
    return
  }
  fmt.Printf("Person: %+v\n", s)
}

Output

Error: unexpected end of JSON input

In this example, the jsonData variable contains an incomplete JSON string (missing the closing }), which would result in the “unexpected end of JSON input” error.

You can fix the error by correcting the JSON input.

jsonData := `{"name":"Krunal", "age": 30}`

In a real-world scenario, the JSON input might come from an external source like a file or an API response.

You should always validate the JSON input before attempting to unmarshal it.

If you presume the JSON input might be empty, you can add a check before calling the json.Unmarshal() function.

if len(jsonData) == 0 {
  fmt.Println("Error: Empty JSON input")
  return
}

That’s it!

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