package main import ( "encoding/json" "errors" "mime" "net/http" "strings" ) type redditList struct { Data struct { Children []struct { Data EarthPorn `json:"data"` } `json:"children"` } `json:"data"` } type EarthPorn struct { Title string `json:"title"` URL string `json:"url,omitempty"` Permalink string `json:"permalink"` } const earthPornURL = "http://www.reddit.com/r/EarthPorn.json" func GetEarthPorn() (EarthPorn, error) { resp, err := http.Get(earthPornURL) if err != nil { return EarthPorn{}, err } defer resp.Body.Close() var list redditList dec := json.NewDecoder(resp.Body) if err := dec.Decode(&list); err != nil { return EarthPorn{}, err } for _, el := range list.Data.Children { p := el.Data if p.URL == "" { continue } if (&p).getImageURL() { return p, nil } } return EarthPorn{}, errors.New("Could not get EarthPorn: No image could be extracted") } func (p *EarthPorn) getImageURL() bool { // TODO: We can do further processing here (e.g. if we get a link to flickr, extract the image). // For now, we will simply test, if the URL points to an image. resp, err := http.Head(p.URL) if err != nil { return false } defer resp.Body.Close() t := resp.Header.Get("Content-Type") if t == "" { return false } mt, _, err := mime.ParseMediaType(t) if err != nil { return false } return (strings.Split(mt, "/")[0] == "image") }