Damon Bauer
Find or Create By (Rails)
Recently on a Rails project, I had the need to create a shelf record and associate it with a book record. (These particular records are using a has_many :through relationship).
The problem I ran into was the need to search for a book to associate with; if it didn't exist, I needed to create it first... I found that Rails has me covered.
find_or_create_by will either find a record with the provided attributes, or create it. (shocker)
Here's how I used it:
def add
shelf = find_or_create_shelf
book = find_or_create_book
SavedBook.create(book_id: book.id, shelf_id: shelf.id)
redirect_to user_to_read_path(params[:user_id]), notice: '✓ Book saved for later.'
end
private
def find_or_create_book
Book.find_or_create_by(id: params[:book_id],
image: params.dig(:book, :image),
title: params.dig(:book, :title),
author: params.dig(:book, :author))
end
def find_or_create_shelf
Shelf.find_or_create_by(user_id: params[:user_id])
end