I wrote this very basic parser that goes through Reddit JSON and am curious how I can specifically manage an error in Go.
For example I have this "Get" method for a link:
func Get(reddit string) ([]Item, error) {
url := fmt.Sprintf("http://reddit.com/r/%s.json", reddit)
resp, err := http.Get(url)
if err != nil {
return nil, err
}
defer resp.Body.Close()
if resp.StatusCode != http.StatusOK {
return nil, err
}
/*
* Other code here
*/
}
How can I handle, say, a 404 error from the StatusCode? I know I can test for the 404 error itself:
if resp.StatusCode == http.StatusNotfound {
//do stuff here
}
But is there a way I can directly manage the resp.StatusCode != http.StatusOK without having to write a bunch of if statements? Is there a way I can use err in a switch statement?
Firstly note that http.Get doesn't return an error for an HTTP return which isn't 200. The Get did its job successfully even when the server gave it a 404 error. From the docs
A non-2xx response doesn't cause an error.
Therfore in your code, err will be nil when you call this which means it will return err=nil which probably isn't what you want.
if resp.StatusCode != http.StatusOK {
return nil, err
}
This should do what you want
if resp.StatusCode != http.StatusOK {
return nil, fmt.Errorf("HTTP Error %d: %s", resp.StatusCode, resp.Status)
}
Which will return an error for any kind of HTTP error, with a message as to what it was.
Sure you can:
package main
import "fmt"
func main() {
var err error
switch err {
case nil:
fmt.Println("Is nil")
}
}