// Create a new artist.
func PostArtists(w http.ResponseWriter, r *http.Request) {
// retrieve route parameters
env := GetRequestEnv(r)
// decode the artist body
var artist models.Artist
if err := json.NewDecoder(r.Body).Decode(&artist); err != nil {
http.Error(w, err.Error(), http.StatusBadRequest)
return
}
// retrieve artist songs so we don't overwrite their fields when
// we create the artist
for i, _ := range artist.Songs {
song := &artist.Songs[i]
if err := env.DB.Find(&song).Error; err != nil {
http.Error(w, err.Error(), http.StatusNotFound)
return
}
}
// create the artist
artist.ID = 0
if err := env.DB.Create(&artist).Error; err != nil {
http.Error(w, err.Error(), http.StatusInternalServerError)
return
}
// encode the response
w.Header().Set("Content-Type", "application/json; charset=UTF-8")
w.WriteHeader(http.StatusCreated)
if err := json.NewEncoder(w).Encode(artist); err != nil {
log.Fatal(err)
}
}
// Update an artist.
func PutArtist(w http.ResponseWriter, r *http.Request) {
// retrieve route parameters
env := GetRequestEnv(r)
vars := mux.Vars(r)
id, err := strconv.Atoi(vars["id"])
if err != nil {
http.Error(w, err.Error(), http.StatusInternalServerError)
return
}
// retrieve the artist
var artist models.Artist
if err := env.DB.Find(&artist, id).Error; err != nil {
http.Error(w, err.Error(), http.StatusNotFound)
return
}
// decode the artist body
if err := json.NewDecoder(r.Body).Decode(&artist); err != nil {
http.Error(w, err.Error(), http.StatusBadRequest)
return
}
// retrieve artist songs so we don't overwrite their fields when
// we update the artist
for i, _ := range artist.Songs {
song := &artist.Songs[i]
if err := env.DB.Find(&song).Error; err != nil {
http.Error(w, err.Error(), http.StatusNotFound)
return
}
}
// start a transaction for updating the artist
tx := env.DB.Begin()
// update the artist songs
if err := tx.Model(&artist).Association("Songs").Replace(artist.Songs).Error; err != nil {
tx.Rollback()
http.Error(w, err.Error(), http.StatusInternalServerError)
return
}
// save the updated artist using the original primary key
artist.ID = id
if err := tx.Save(&artist).Error; err != nil {
tx.Rollback()
http.Error(w, err.Error(), http.StatusInternalServerError)
return
}
// commit the transaction
if err := tx.Commit().Error; err != nil {
http.Error(w, err.Error(), http.StatusInternalServerError)
return
}
// encode the response
w.Header().Set("Content-Type", "application/json; charset=UTF-8")
w.WriteHeader(http.StatusOK)
if err := json.NewEncoder(w).Encode(artist); err != nil {
log.Fatal(err)
}
}