Rails and unexisting parameters - ruby-on-rails-3

I have a code like this:
User.create(params[:user])
But if someone sends params through API like
{"userr":{"name":"Firstname"}}
then I get 500 error because of undefined method * for nil:NilClass. How should I handle this and should I at all?

Of course you should handle false input - this is a situation which might happen in production as well.
I'd simply do:
if params[:user].blank?
# Handle false input here
else
User.create(params[:user])
end

Related

How to stop further routing in a plug?

I'm using Phoenix, and in router.ex, I have defined a function that verifies the user's JWT token, before continuing on to routing through the api, in order to protect the routes. However, I am having the issue that if, say, I return a status of 403 in the plug, it continues routing and I end up getting an error as I am both accessing the route and disallowing access.
My code looks something like this:
def validate(conn, _opts) do
if !Map.has_key?(conn.cookies, "jwt") do
conn
|> send_resp(403, "Forbidden")
# I would like to have something here that stops further
# routing - i.e. a way to say 'already sent a response; don't keep going'
end
end
Here is an excerpt from Plug.Conn.send_resp/3
Note that this function does not halt the connection, so if subsequent plugs try to send another response, it will error out. Use halt/1 after this function if you want to halt the plug pipeline.

Flask Error: If something fails in the flask backend, how does the error propagate to the front end?

Consider a simple application where a user fills a form to divide two numbers, in the routes the form data is proceeded [made into float] and then passed as parameters to a python script's function that has the division logic.
The logic fails due to division by 0 is handled as a custom message in the terminal. How does one send this custom message back to the front end UI along with a 500 error message? Trying to make a restful flask app here.
So far I can abort and show a custom message but not the one that propagated from the backend. Also looked into custom error handling but I want to writer of the external python script to be able to write the custom message.
You can Flask errorhandler(errorcode) to manage your errors and display those on the frontend.
#app.errorhandler(500)
def code_500(error):
return render_template("errors/500.html", error=error), 500
You can put whatever else you want in the html template.
You can also call the code_500(error) func directly.
Same principle applies for any other HTTP error code if you want to customize the page and the message (401, 403, 404, etc...).
If you're inside a blueprint, you can use app_errorhandler instead.
You could use the abort() function. From the docs:
When using Flask for web APIs, you can use the same techniques as above to return JSON responses to API errors. abort() is called with a description parameter. The errorhandler() will use that as the JSON error message, and set the status code to 404.
You could implement it like this
#app.route("/div")
def divide():
x, y = request.form['x'], request.form['y']
try:
result = x / y
except ZeroDivisionError:
abort(400, description="Your message here")
else:
# Proper response
From there, the important step is properly catching that message on your frontend.

Post method gets converted to GET after redirection

I have one POST call related to search.It is like I am sending some data as parameters to call and some in payload.after getting 302 it gets redirected.But the issue is once it gets redirected,POST call gets converted to GET call and payload is lost.As a result I am unable to get desired search result.Is there anything related to config that I might be missing??
Yes this is the correct behavior. Sounds like you need to disable automatic re-directs for this test, see configure. You can do:
* configure followRedirects = false
And then get the redirect location manually as follows:
* def location = responseHeaders['Location'][0]
Refer to this test for an example: redirect.feature

wrong params in url with Rails

Here is my url : /creations/stock?id=3
When I click to my link creations_stock_path(:id => creation.id) I have an error Couldn't find Creation with id=stock. I really don't understand the problem, I have the same for another object (products) and it works.
When I check what are send with my params, I have
>> params
=> {"id"=>"stock", "action"=>"show", "controller"=>"creations"}
Why ??? In my controller, I wrote :
def stock
#creation = Creation.find(params[:id])
end
So I don't understand first why rails want to use Show action and also why my params are wrong...
Any idea ?
Edit : My routes.rb file :
get "creations/stock"
get "products/stock"
The error means that there's no Creation record in the database that has an id equal to params[:id]. Check your db to see if the record exists. This exception shows a 404 page when running in production mode or at least when config.consider_all_requests_local is false.
If you don't want it to raise an exception, try find_by_id instead which will return nil when the record is not found.

How to test with RSpec if an email is delivered

I'd like to test if an email is delivered if I call a controller method with :post. I'll use email_spec so I tried this snipped here: http://rubydoc.info/gems/email_spec/1.2.1/file/README.rdoc#Testing_In_Isolation
But it doesn't work, because I pass an instance of the model-object to the delivery-method and the instance is saved before the delivery.
I tried to create an other instance of the model-object, but then the id isn't the same.
My controller-method looks like this:
def create
#params = params[:reservation]
#reservation = Reservation.new(#params)
if #reservation.save
ReservationMailer.confirm_email(#reservation).deliver
redirect_to success_path
else
#title = "Reservation"
render 'new'
end
end
Do you have any idea to solve this?
Assuming your test environment is set up in the usual fashion (that is, you have config.action_mailer.delivery_method = :test), then delivered emails are inserted into the global array ActionMailer::Base.deliveries as Mail::Message instances. You can read that from your test case and ensure the email is as expected. See here.
Configure your test environment to accumulate sent mails in ActionMailer::Base.deliveries.
# config/environments/test.rb
config.action_mailer.delivery_method = :test
Then something like this should allow you to test that the mail was sent.
# Sample parameters you would expect for POST #create.
def reservation_params
{ "reservation" => "Drinks for two at 8pm" }
end
describe MyController do
describe "#create" do
context "when a reservation is saved" do
it "sends a confirmation email" do
expect { post :create, reservation_params }.to change { ActionMailer::Base.deliveries.count }.by(1)
end
end
end
end
Note that my example uses RSpec 3 syntax.
I know I'm late to the party with this one, but for future Googlers...
I think a better solution to this problem is answered here
The previously accepted answer is testing the Mailer itself (inside the controller spec). All you should be testing for here is that the Mailer gets told to deliver something with the right parameters.
You can then test the Mailer elsewhere to make sure it responds to those parameters correctly.
ReservationMailer.should_receive(:confirm_email).with(an_instance_of(Reservation))
This is way how to test that Mailer is called with right arguments. You can use this code in feature, controller or mailer spec:
delivery = double
expect(delivery).to receive(:deliver_now).with(no_args)
expect(ReservationMailer).to receive(:confirm_email)
.with('reservation')
.and_return(delivery)
Anyone using rspec +3.4 and ActiveJob to send async emails, try with:
expect {
post :create, params
}.to have_enqueued_job.on_queue('mailers')
To add a little more, make sure if you're going to stub out a call using should_receive that you have an integration test elsewhere testing that you're actually calling the method correctly.
I've been bit a few times by changing a method that was tested elsewhere with should_receive and having tests still pass when the method call was broken.
If you prefer to test the outcome rather than using should_receive, shoulda has a nice matcher that works like the following:
it { should have_sent_email.with_subject(/is spam$/) }
Shoulda documentation
More information on using Shoulda Matchers with rSpec
If you're using Capybara with Capybara Email and you sent an email to test#example.com, you can also use this method:
email = open_email('test#example.com')
And then you can test it like this:
expect(email.subject).to eq('SUBJECT')
expect(email.to).to eq(['test#example.com'])
Try email-spec
describe "POST /signup (#signup)" do
it "should deliver the signup email" do
# expect
expect(UserMailer).to(receive(:deliver_signup).with("email#example.com", "Jimmy Bean"))
# when
post :signup, "Email" => "email#example.com", "Name" => "Jimmy Bean"
end
end
more examples here: https://github.com/email-spec/email-spec#testing-in-isolation