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Agile Web Development with Rails 8: B6.0(page 126)

bunnahabhain

bunnahabhain

Agile Web Development with Rails 8: B6.0(page 126)

Code shows:

@line_item = @cart.line_items.build(product: product)

This produces an error of " * Product must exist" when you press the “Add to Cart” button.

However, if I change the line to add “.id” to product, then it works as expected:

@line_item = @cart.line_items.build(product_id: product.id)

2 comments
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Marked As Solved

bunnahabhain

bunnahabhain

I have resolved the issue by recreating the depot app from the beginning. I had been avoiding doing so as I was following along with each beta release of the book, and had been building upon the chapters that I had already completed.

I have a feeling that it might have simply been an issue with a bad record in the database, as I recall pressing the “new product” button before completing the code that went along with the button. Unfortunately, I had dropped and recreated the database before I thought to take a look at it.

Please consider this issue closed. Thanks!

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