Go - Creating JSON Data from Structs

Problem: You want to create JSON data from a struct.

Solution: Create the structs then use the json.Marshal or json.MarshalIndent to marshal the data into a JSON slice of bytes.

 

func main() {
    person := struct{}

    data, err := json.Marshal(&person)
    if err != nil {
        log.Println("Cannot  marshal  person:", err)
    }
    err = os.WriteFile("han.json", data, 0644)
    if err != nil {
        log.Println("Cannot  write  to  file", err)
    }
}

 

The file is not very readable. If you want a more readable version, you can use json.Mar⁠shalIndent instead. You need to put in two more parameters: the first is the prefix, and the second is the indent. Mostly if you want to have a clean JSON output, the prefix is an empty string while the indent is a single space:

data, err := json.MarshalIndent(&person, "", "  ")