Last active
August 21, 2024 05:26
-
-
Save mattetti/3798173 to your computer and use it in GitHub Desktop.
async fetching of urls using goroutines and channels
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
package main | |
import ( | |
"fmt" | |
"net/http" | |
"time" | |
) | |
var urls = []string{ | |
"https://splice.com/", | |
"https://golang.org/", | |
"https://matt.aimonetti.net/", | |
} | |
type HttpResponse struct { | |
url string | |
response *http.Response | |
err error | |
} | |
func asyncHttpGets(urls []string) []*HttpResponse { | |
ch := make(chan *HttpResponse, len(urls)) // buffered | |
responses := []*HttpResponse{} | |
for _, url := range urls { | |
go func(url string) { | |
fmt.Printf("Fetching %s \n", url) | |
resp, err := http.Get(url) | |
if err == nil { | |
resp.Body.Close() | |
} | |
ch <- &HttpResponse{url, resp, err} | |
}(url) | |
} | |
for { | |
select { | |
case r := <-ch: | |
fmt.Printf("%s was fetched\n", r.url) | |
responses = append(responses, r) | |
if len(responses) == len(urls) { | |
return responses | |
} | |
case <-time.After(50 * time.Millisecond): | |
fmt.Printf(".") | |
} | |
} | |
return responses | |
} | |
func main() { | |
results := asyncHttpGets(urls) | |
for _, result := range results { | |
if result.err != nil { | |
fmt.Printf("%s error: %v\n", result.url, | |
result.err) | |
continue | |
} | |
fmt.Printf("%s status: %s\n", result.url, | |
result.response.Status) | |
} | |
} |
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
@DudeFactory I fixed the example, try with your domains now. The problem was that my quick fix was skipping writing to the channel in case of error so I didn't have to check if there was an error. The fix was to check for errors when reading from the channel and print the proper statement.