+ var genreId int64
+ row := env.Db.Db.QueryRow(`
+SELECT ID
+FROM GENRE
+WHERE NAME = lower(?)
+`,
+ genre,
+ )
+
+ err := row.Scan(&genreId)
+ if err == sql.ErrNoRows {
+ result, err := env.Db.Db.Exec(`
+INSERT INTO GENRE
+(NAME)
+VALUES (?)`,
+ genre,
+ )
+ if err != nil {
+ log.Printf("Failed to insert genre %s: %s", genre, err.Error())
+ http.Error(w, http.StatusText(http.StatusInternalServerError), http.StatusInternalServerError)
+ return
+ }
+
+ genreId, err = result.LastInsertId()
+ if err != nil {
+ log.Print("Failed to retrieve last insert id: ", err.Error())
+ http.Error(w, http.StatusText(http.StatusInternalServerError), http.StatusInternalServerError)
+ return
+ }
+ }
+
+ env.Db.Db.Exec(`
+INSERT INTO ARTIST_GENRE_XREF
+(ARTIST_ID, GENRE_ID)
+VALUES (?, ?)`,
+ artist.ID,
+ genreId,
+ )
+ }
+ w.WriteHeader(http.StatusCreated)
+ }
+}
+
+func ByGenre(env *env.Env) routes.Handler {
+ return func(w http.ResponseWriter, r *http.Request) {
+ if r.Method != "GET" {
+ http.Error(w, http.StatusText(http.StatusMethodNotAllowed), http.StatusMethodNotAllowed)
+ return
+ }
+
+ w.Header().Set("Content-Type", "application/json")
+ genreName := r.FormValue("genre_name")
+ if genreName != "" {
+ rows, err := env.Db.Db.Query(`
+SELECT a.ID, a.NAME
+FROM ARTIST a
+JOIN ARTIST_GENRE_XREF x ON a.ID = x.ARTIST_ID
+JOIN GENRE g ON g.ID = x.GENRE_ID
+WHERE g.NAME = lower(?)
+`,
+ genreName,
+ )