prevent overposting

main.go

@@ -49,12 +49,20 @@ func postAlbums(c *gin.Context) {
 	// Call BindJSON to bind the received JSON to
 	// newAlbum.
 	if err := c.BindJSON(&newAlbum); err != nil {
+		c.Status(http.StatusBadRequest)
 		return
 	}
 
+	for _, a := range albums {
+		if a == newAlbum {
+			c.Status(http.StatusBadRequest)
+			return
+		}
+	}
+
 	// Add the new album to the slice.
 	albums = append(albums, newAlbum)
-	c.IndentedJSON(http.StatusCreated, newAlbum)
+	c.JSON(http.StatusCreated, newAlbum)
 }
 
 // getAlbumByID locates the album whose ID value matches the id