Discussion on: Making concurrent API requests in Go

[Adeniyi Stephen Oluwatola]

package main

import (
    "encoding/json"
    "fmt"
    "log"
    "net/http"
    "time"
)

type Comic struct {
    Num   int    `json:"num"`
    Link  string `json:"link"`
    Img   string `json:"img"`
    Title string `json:"title"`
}

const baseXkcdURL = "https://xkcd.com/%d/info.0.json"

func GetComic(comicID int) (comic Comic, err error) {
    url := fmt.Sprintf(baseXkcdURL, comicID)
    response, err := http.Get(url)
    if err != nil {
        log.Println(err)
    }

    err = json.NewDecoder(response.Body).Decode(&comic)
    if err != nil {
        log.Println(err)
    }

    return comic, nil
}

func main() {
    start := time.Now()
    defer func() {
        fmt.Println("Execution Time: ", time.Since(start).Seconds())
    }()

    comicsNeeded := []int{1, 2, 3, 4, 5, 6, 7, 8, 9, 10}

    ch := make(chan Comic)

    for _, id := range comicsNeeded {
        go func(id int) {
            comic, err := GetComic(id)
            if err != nil {
                log.Println("error getting comic", err)
            }
            ch <- comic
        }(id)
    }

    var comics []Comic
    for i := 0; i < len(comicsNeeded); i++{
        comm := <-ch
        comics = append(comics, comm)
        fmt.Println("Fetched comic", comicsNeeded[i], "of title:", comics[i].Title)
    }
}

Here's an updated code with channels also making it faster and ran for 1 sec