Handling HTTP Request Errors
写个简单的小例子，自己做个端点，返回状态码 500。
package main
import (
"log"
"net/http"
)
func main() {
http.HandleFunc("/500", func(w http.ResponseWriter, r *http.Request) {
w.WriteHeader(500)
w.Write([]byte("NOT-OK"))
})
go http.ListenAndServe(":8080", nil)
_, err := http.Get("http://localhost:8080/500")
if err != nil {
log.Fatal(err)
}
}
我们期望抛错的地方并没有执行，原因是因为。
An error is returned if the Client’s CheckRedirect function fails or if there was an HTTP protocol error. A non-2xx response doesn’t cause an error.
所以 GET 请求应该按照下面的写法，自己手动处理非 200 的状态码。
package main
import (
"fmt"
"io/ioutil"
"log"
"net/http"
)
func main() {
resp, err := http.Get("https://httpbin.org/get")
// 域名无法访问的时候才会抛错
if err != nil {
// Print the message and then calls os.Exit to terminate the program.
log.Fatalln(err)
}
// An error is returned if there were too many redirects or if there was an HTTP protocol error.
// A non-2xx response doesn’t cause an error.
// 需要我们自己处理状态码非 200 的情况
if resp.StatusCode != 200 {
b, _ := ioutil.ReadAll(resp.Body)
fmt.Println("second err")
log.Fatal(string(b))
}
// Forgetting to close the response body can cause resource leaks in a long running programs.
defer resp.Body.Close()
body, err := ioutil.ReadAll(resp.Body)
if err != nil {
fmt.Println("second err")
log.Fatalln(err)
}
log.Println(string(body))
}
