Circular links between structs lead to massive memory consumption and a killed program #278
Description
As the title says, using a struct schema which has circular links (as can happen using an ORM like GORM), the memory usage explodes and the program is killed. I have created a small repo with the minimal code to reproduce the issue. I have also attached some code directly below. https://github.com/SetorHabona/gocsv-mem-leak
NOTE: An easy fix is excluding the inner struct using csv:"-"
package main
import (
"fmt"
"os"
"github.com/gocarina/gocsv"
)
// this setup is not not very unusual when working with gorm (maybe also other ORMs)
type Wrapper struct {
Name string `csv:"name"`
Age uint `csv:"age"`
// Inner creates a problem, both as pointer and as value
Inner *Inner // add `csv:"-"` to avoid rapid increase in consumed memory and your program being killed
}
type Inner struct {
Position string
Salary uint
Wrappers *Wrapper
}
func main() {
file, err := os.OpenFile("./data.csv", os.O_RDWR|os.O_CREATE, os.ModePerm)
if err != nil {
panic(err)
}
defer file.Close()
var wraps []Wrapper
if err := gocsv.UnmarshalFile(file, &wraps); err != nil {
panic(err)
}
fmt.Printf("%+v\n", wraps)
}