mert

mert

Agile Web Development with Rails 7: page 120

Hello everyone,

I am relatively new to rails. I am reading AWDWR 7.

I am at page 120, I have some questions and having some problems.

Questions:

  • In line_item model we create a relationship to product and cart models. Do we need a n x m relationship between product and cart models? Because of that we create the line_item model?

  • Also inside the product and cart models we have has_many :line_items. Where is these relationships inside our schema.rb? I don’t see any sql relationship? If we don’t have a sql relationship is it good way to create relationships in ruby?

Need help code debugging:

  • I think I am having some problem. inside the line_items_controller.rb in the create method at @line_item = @cart.line_items.build(product: product) it gives me error. Saying : ActiveModel::MissingAttributeError in LineItemsController#create
    can’t write unknown attribute product_id. Any helps solving this problem

Thank you @rubys for this book!

Have a great day!

Mert

Marked As Solved

rubys

rubys

Author of Agile Web Development With Rails

It looks like your line_items are missing both a product and a cart. Those should have been added when you generated your scaffold in Iteration D2.

You can add them now with the following:

bin/rails generate migration AddProductAndCartToLineItems product:references cart:belongs_to

Where Next?

Popular Pragmatic Bookshelf topics Top

abtin
page 20: … protoc command… I had to additionally run the following go get commands in order to be able to compile protobuf code using go...
New
johnp
Running the examples in chapter 5 c under pytest 5.4.1 causes an AttributeError: ‘module’ object has no attribute ‘config’. In particula...
New
jesse050717
Title: Web Development with Clojure, Third Edition, pg 116 Hi - I just started chapter 5 and I am stuck on page 116 while trying to star...
New
Alexandr
Hi everyone! There is an error on the page 71 in the book “Programming machine learning from coding to depp learning” P. Perrotta. You c...
New
alanq
This isn’t directly about the book contents so maybe not the right forum…but in some of the code apps (e.g. turbo/06) it sends a TURBO_ST...
New
New
brian-m-ops
#book-python-testing-with-pytest-second-edition Hi. Thanks for writing the book. I am just learning so this might just of been an issue ...
New
dsmith42
Hey there, I’m enjoying this book and have learned a few things alredayd. However, in Chapter 4 I believe we are meant to see the “>...
New
jwandekoken
Book: Programming Phoenix LiveView, page 142 (157/378), file lib/pento_web/live/product_live/form_component.ex, in the function below: d...
New
andreheijstek
After running /bin/setup, the first error was: The foreman' command exists in these Ruby versions: That was easy to fix: gem install fore...
New

Other popular topics Top

AstonJ
Curious to know which languages and frameworks you’re all thinking about learning next :upside_down_face: Perhaps if there’s enough peop...
New
Rainer
My first contact with Erlang was about 2 years ago when I used RabbitMQ, which is written in Erlang, for my job. This made me curious and...
New
AstonJ
I’ve been hearing quite a lot of comments relating to the sound of a keyboard, with one of the most desirable of these called ‘thock’, he...
New
AstonJ
This looks like a stunning keycap set :orange_heart: A LEGENDARY KEYBOARD LIVES ON When you bought an Apple Macintosh computer in the e...
New
PragmaticBookshelf
Build highly interactive applications without ever leaving Elixir, the way the experts do. Let LiveView take care of performance, scalabi...
New
PragmaticBookshelf
Use WebRTC to build web applications that stream media and data in real time directly from one user to another, all in the browser. ...
New
mafinar
This is going to be a long an frequently posted thread. While talking to a friend of mine who has taken data structure and algorithm cou...
New
New
AstonJ
This is cool! DEEPSEEK-V3 ON M4 MAC: BLAZING FAST INFERENCE ON APPLE SILICON We just witnessed something incredible: the largest open-s...
New
NewsBot
Node.js v22.14.0 has been released. Link: Release 2025-02-11, Version 22.14.0 'Jod' (LTS), @aduh95 · nodejs/node · GitHub
New

Latest in Agile Web Development with Rails 7

Agile Web Development with Rails 7 Portal

Sub Categories: