10.3 Iteration E3: Finishing the Cart 10.1 Iteration E1: Creating a Smarter Cart
Log errors and show them on the screen.
Rescue error: log, flash, and redirect.
edit app/controllers/carts_controller.rb
# GET /carts/1
# GET /carts/1.xml
def show
begin
@cart = Cart.find(params[:id])
rescue ActiveRecord::RecordNotFound
logger.error "Attempt to access invalid cart #{params[:id]}"
redirect_to store_url, :notice => 'Invalid cart'
else
respond_to do |format|
format.html # show.html.erb
format.xml { render :xml => @cart }
end
end
end
Reproduce the error.
get /carts/wibble
get http://localhost:3000/
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Invalid cart
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Inspect the log.
tail -25 log/development.log
/home/rubys/.rvm/rubies/ruby-1.9.3-r28190/lib/ruby/1.9.1/webrick/server.rb:183:in `block in start_thread'
Rendered /home/rubys/git/rails/actionpack/lib/action_dispatch/middleware/templates/rescues/_trace.erb (1.7ms)
Rendered /home/rubys/git/rails/actionpack/lib/action_dispatch/middleware/templates/rescues/_request_and_response.erb (4.3ms)
Rendered /home/rubys/git/rails/actionpack/lib/action_dispatch/middleware/templates/rescues/diagnostics.erb within rescues/layout (10.5ms)
Started GET "/carts/wibble" for 127.0.0.1 at 2010-06-06 10:35:26 -0400
Processing by CartsController#show as HTML
Parameters: {"id"=>"wibble"}
SQL (0.6ms) *[1m SELECT name
FROM sqlite_master
WHERE type = 'table' AND NOT name = 'sqlite_sequence'
*[0m
Cart Load (0.3ms) SELECT "carts".* FROM "carts" WHERE ("carts"."id" = 0) LIMIT 1
Attempt to access invalid cart wibble
Redirected to http://localhost:3000/
Completed 302 Found in 20ms
Started GET "/" for 127.0.0.1 at 2010-06-06 10:35:27 -0400
Processing by StoreController#index as */*
Product Load (1.0ms) *[1mSELECT "products".* FROM "products" ORDER BY title*[0m
Rendered store/index.html.erb within layouts/application (25.8ms)
Completed 200 OK in 67ms (Views: 42.1ms | ActiveRecord: 1.0ms)
10.3 Iteration E3: Finishing the Cart 10.1 Iteration E1: Creating a Smarter Cart