Design:

When a user gets logged into website, the user can search books in the following way:

• There will be a search box where user can give the isbn number or title of the book or author of the book and press search button.
• Then the user will be directed in to a page, where user can see the books.

Implementation:

• As soon as user gets logged into website, user can see a search box in "/search" page, where user can give the isbn number or title of the book or author of the book.
• There will be a "search" button below search box, if user presses that button then the user will be redirected "/results" page where the books will be displayed to the user.

Testing:

• Test case to check if the user had given any text in the search box. If not, error message will be displayed on the search page.
• Test case to check if the user had given valid input. If not, error message "Give a valid input" is displayed on the search page