I've got a nested resource of User Reading Lists (a User has_many Reading Lists). I'm trying to mock everything in my controller specs, but having trouble keeping it concise. Here's the before code for the #show action:
#reading_lists = mock("Reading lists")
#reading_lists.stub!(:find).with("1").and_return(#reading_list)
#user = mock_model(User, :reading_lists => #reading_lists)
User.stub!(:find).with("1").and_return(#user)
get :show, :user_id => "1", :id => "1"
which is testing:
def show
#user = User.find(params[:user_id])
#reading_list = #user.reading_lists.find params[:id]
end
This seems like a crazy amount of boilerplate - is there a better way to mock it out?
There is not a better way to mock it out, but you are right to note that this is a lot of boiler plate. The reason is that user.reading_lists.find is a Law of Demeter violation. Whether or not you view the Law of Demeter as important, mocking through violations of it is painful.
I'd recommend either using the real models or simplifying the interaction with the model. I can't really say how without seeing what you're trying to specify.
Related
I have two models, User and Account.
# account.rb
belongs_to :user
# user.rb
has_one :account
Account has an attribute name. And in my views, I was calling current_user.account.name multiple times, and I heard that's not the great of a way to do it. So I was incredibly swift, and I created the following method in my user.rb
def account_name
self.account.name
end
So now in my view, I can simply call current_user.account_name, and if the association changes, I only update it in one place. BUT my question is, do I test this method? If I do, how do I test it without any mystery guests?
I agree there is nothing wrong with current_user.account.name - while Sandi Metz would tell us "User knows too much about Account" this is kind of the thing you can't really avoid w/ Active Record.
If you found you were doing a lot of these methods all over the User model you could use the rails delegate method:
delegate :name, :to => :account, :prefix => true
using the :prefix => true option will prefix the method in the User model so it is account_name. In this case I would assume you could write a very simple unit test on the method that it returns something just incase the attribute in account would ever change your test would fail so you would know you need to update the delegate method.
There's nothing wrong with current_user.account.name
There's no difference between calling it as current_user.account.name, or making current_user.account_name call it for you
You're probably not calling current_user in the model, like you say
You should have a spec for it if you use it
Personally I see no good reason for any of this. Just use current_user.account.name.
If you are worrying about efficiency, have current_user return a user that joins account.
This is going to be a bit off-topic. So, apologies in advance if it's not interesting or helpful.
TL;DR: Don't put knowledge of your models in your views. Keep your controllers skinny. Here's how I've been doing it.
In my current project, I've been working to make sure my views have absolutely no knowledge of anything about the rest of the system (to reduce coupling). This way, if you decide to change how you implement something (say, current_user.account.name versus current_user.account_name), then you don't have to go into your views and make changes.
Every controller action provides a #results hash that contains everything the view needs to render correctly. The structure of the #results hash is essentially a contract between the view and the controller.
So, in my controller, #results might look something like {current_user: {account: {name: 'foo'}}}. And in my view, I'd do something like #results[:current_user][:account][:name]. I like using a HashWithIndifferentAccess so I could also do #results['current_user']['account']['name'] and not have things blow up or misbehave.
Also, I've been moving as much logic as I can out of controllers into service objects (I call them 'managers'). I find my managers (which are POROs) a lot easier to test than controllers. So, I might have:
# app/controllers/some_controller.rb
class SomeController
def create
#results = SomeManager.create(params)
if #results[:success]
# happy routing
else
# sad routing
end
end
end
Now, my controllers are super skinny and contain no logic other than routing. They don't know anything about my models. (In fact, almost all of my controller actions look exactly the same with essentially the same six lines of code.) Again, I like this because it creates separation.
Naturally, I need the manager:
#app/managers/some_manager.rb
class SomeManager
class << self
def create(params)
# do stuff that ends up creating the #results hash
# if things went well, the return will include success: true
# if things did not go well, the return will not include a :success key
end
end
end
So, in truth, the structure of #results is a contract between the view and the manager, not between the view and the controller.
Frustrating, I can't find an eligible solution for my problem.
In my Rails 4 app, I want to give my users the possibility to add their own custom post types to their sites. Like:
www.example.com/houses/address-1
www.example2.com/sports/baseball
Both would work, but only for the linked sites. Sports and houses would be the (RESTful) post types, taken from the db, added by users.
I have been struggling to find a elegant solution to accomplish this. I found http://codeconnoisseur.org/ramblings/creating-dynamic-routes-at-runtime-in-rails-4 but that feels kinda hacky and I'm not sure if reloading the routes works in production, I'm getting signals that it won't.
I'd say I have to use routes constraints http://guides.rubyonrails.org/routing.html#advanced-constraints but I don't have a clue how to approach this.
To be clear, I have no problem with the site setting stuff, the multi tenancy part of my app is fully functional (set in Middleware, so the current site is callable in the routes.rb file). My issue is with the (relative) routes, and how they could be dynamically set with db records.
Any pointers much appreciated.
I think route constraints don't work for you because your domain is a variable here. Instead, you should be examining the request object.
In your ApplicationController, you could define a method that would be called before any action, like so:
class ApplicationController < ActionController::Base
before_action :identify_site
def identify_site
#site = Site.where(:domain => request.host).first
end
end
As you scale, you could use Redis for your domains so you're not making an expensive SQL call on each request.
Then you can just add the #site as a parameter to whatever call you're making. I'm assuming you're doing some sort of "Post" thing, so I'll write some boilerplate code:
class PostController < ApplicationController
def show
#post = Post.where(:site => #site, :type => params[:type], :id => params[:id])
end
end
Just write your routes like any other regular resource.
I'm having trouble coming up with some tests for a method I want to write.
The method is going to take a hash of some data and create a bunch of associated models with it. The problem is, I'm having a hard time figuring out what the best practice for writing this sort of test is.
For example, the code will:
Take a hash that looks like:
{
:department => 'CS',
:course_title => 'Algorithms',
:section_number => '01B'
:term => 'Fall 2012',
:instructor => 'Bob Dylan'
}
And save it to the models Department, Course, Section, and Instructor.
This will take many calls to model.find_or_create, etc.
How could I go about testing each separate purpose of this method, e.g.:
it 'should find or create department' do
# << Way too many stubs here for each model and all association calls
dept = mock_model(Department)
Department.should_receive(:find_or_create).with(:name => 'CS').and_return(dept)
end
Is there a way to avoid the massive amounts of stubs to keep each test FIRST (fast independent repeatable self-checking timely) ? Is there a better way to write this method and/or these tests? I'd really prefer to have short, clean it blocks.
Thank you so much for any help.
Edit:
The method will probably look like this:
def handle_course_submission(param_hash)
department = Department.find_or_create(:name => param_hash[:department])
course = Course.find_or_create(:title => param_hash[:course_title])
instructor = Instructor.find_or_create(:name => param_hash[:instructor])
section = Section.find_or_create(:number => param_hash[:section_number], :term => param_hash[:term])
# Maybe put this stuff in a different method?
course.department = department
section.course = course
section.instructor = instructor
end
Is there a better way to write the method? How would I write the tests? Thanks!
For passing an array of sections to be created:
class SectionCreator
# sections is the array of parameters
def initialize(sections)
#sections = sections
end
# Adding the ! here because I think you should use the save! methods
# with exceptions as mentioned in one of my myriad comments.
def create_sections!
#sections.each do |section|
create_section!(section)
end
end
def create_section!(section)
section = find_or_create_section(section[:section_number], section[:term])
section.add_course!(section_params)
end
# The rest of my original example goes here
end
# In your controller or wherever...
def action
SectionCreator.new(params_array).create_sections!
rescue ActiveRecord::RecordInvalid => ex
errors = ex.record.errors
render json: errors
end
Hopefully this covers it all.
My first thought is that you may be suffering from a bigger design flaw. Without seeing the greater context of your method it is hard to give much advice. However, in general it is good to break the method up into smaller pieces and follow the single level of abstraction principle.
http://www.markhneedham.com/blog/2009/06/12/coding-single-level-of-abstraction-principle/
Here is something you could try although as mentioned before this is definitely still not ideal:
def handle_course_submission(param_hash)
department = find_or_create_department(param_hash[:department])
course = find_or_create_course(param_hash[:course_title])
# etc.
# call another method here to perform the actual work
end
private
def find_or_create_department(department)
Department.find_or_create(name: department)
end
def find_or_create_course(course_title)
Course.find_or_create(title: course_title)
end
# Etc.
In the spec...
let(:param_hash) do
{
:department => 'CS',
:course_title => 'Algorithms',
:section_number => '01B'
:term => 'Fall 2012',
:instructor => 'Bob Dylan'
}
end
describe "#save_hash" do
before do
subject.stub(:find_or_create_department).as_null_object
subject.stub(:find_or_create_course).as_null_object
# etc.
end
after do
subject.handle_course_submission(param_hash)
end
it "should save the department" do
subject.should_receive(:find_or_create_department).with(param_hash[:department])
end
it "should save the course title" do
subject.should_receive(:find_or_create_course).with(param_hash[:course_title])
end
# Etc.
end
describe "#find_or_create_department" do
it "should find or create a Department" do
Department.should_receive(:find_or_create).with("Department Name")
subject.find_or_create_department("Department Name")
end
end
# etc. for the rest of the find_or_create methods as well as any other
# methods you add
Hope some of that helped a little. If you post more of your example code I may be able to provide less generalized and possibly useful advice.
Given the new context provided, I would split the functionality up amongst your models a little more. Again, this is really just the first thing that comes to mind and could definitely be improved upon. It seems to me like the Section is the root object here. So you could either add a Section.create_course method or wrap it in a service object like so:
Updated this example to use exceptions
class SectionCreator
def initialize(param_hash)
number = param_hash.delete(:section_number)
term = param_hash.delete(:term)
#section = find_or_create_section(number, term)
#param_hash = param_hash
end
def create!
#section.add_course!(#param_hash)
end
private
def find_or_create_section(number, term)
Section.find_or_create(number: number, term: term)
end
end
class Section < ActiveRecord::Base
# All of your current model stuff here
def add_course!(course_info)
department_name = course_info[:department]
course_title = course_info[:course_title]
instructor_name = param_hash[:instructor]
self.course = find_or_create_course_with_department(course_title, department_name)
self.instructor = find_or_create_instructor(instructor_name)
save!
self
end
def find_or_create_course_with_department(course_title, department_name)
course = find_or_create_course(course_title)
course.department = find_or_create_department(department_name)
course.save!
course
end
def find_or_create_course(course_title)
Course.find_or_create(title: course_title)
end
def find_or_create_department(department_name)
Department.find_or_create(name: department_name)
end
def find_or_create_instructor(instructor_name)
Instructor.find_or_create(name: instructor_name)
end
end
# In your controller (this needs more work but..)
def create_section_action
#section = SectionCreator.new(params).create!
rescue ActiveRecord::RecordInvalid => ex
flash[:alert] = #section.errors
end
Notice how adding the #find_or_create_course_with_department method allowed us to add the association of the department in there while keeping the #add_course method clean. That is why I like to add those methods even though they sometimes seem superflous like in the case of the #find_or_create_instructor method.
The other advantage of breaking out the methods in this fashion is that they become easier to stub in tests as I showed in my first example. You can easily stub all of these methods to make sure the database isn't actually being hit and your tests run fast while at the same time guarantee through the test expectations that the functionality is correct.
Of course, a lot of this comes down to personal preference on how you want to implement it. In this case the service object is probably unnecessary. You could just as easily have implemented that as the Section.create_course method I referenced earlier like so:
class Section < ActiveRecord::Base
def self.create_course(param_hash)
section = find_or_create(number: param_hash.delete(:section_number), term: param_hash.delete(:term))
section.add_course(param_hash)
section
end
# The rest of the model goes here
end
As to your final question, you can definitely stub out methods in RSpec and then apply expectations like should_receive on top of those stubs.
It's getting late so let me know if I missed anything.
Scenario: I have a has_many association (Post has many Authors), and I have a nested Post form to accept attributes for Authors.
What I found is that when I call post.update_attributes(params[:post]) where params[:post] is a hash with post and all author attributes to add, there doesn't seem to be a way to ask Rails to only create Authors if certain criteria is met, e.g. the username for the Author already exists. What Rails would do is just failing and rollback update_attributes routine if username has uniqueness validation in the model. If not, then Rails would add a new record Author if one that does not have an id is in the hash.
Now my code for the update action in the Post controller becomes this:
def update
#post = Post.find(params[:id])
# custom code to work around by inspecting the author attributes
# and pre-inserting the association of existing authors into the testrun's author
# collection
params[:post][:authors_attributes].values.each do |author_attribute|
if author_attribute[:id].nil? and author_attribute[:username].present?
existing_author = Author.find_by_username(author_attribute[:username])
if existing_author.present?
author_attribute[:id] = existing_author.id
#testrun.authors << existing_author
end
end
end
if #post.update_attributes(params[:post])
flash[:success] = 'great!'
else
flash[:error] = 'Urgg!'
end
redirect_to ...
end
Are there better ways to handle this that I missed?
EDIT: Thanks for #Robd'Apice who lead me to look into overriding the default authors_attributes= function that accepts_nested_attributes_for inserts into the model on my behalf, I was able to come up with something that is better:
def authors_attributes=(authors_attributes)
authors_attributes.values.each do |author_attributes|
if author_attributes[:id].nil? and author_attributes[:username].present?
author = Radar.find_by_username(radar_attributes[:username])
if author.present?
author_attributes[:id] = author.id
self.authors << author
end
end
end
assign_nested_attributes_for_collection_association(:authors, authors_attributes, mass_assignment_options)
end
But I'm not completely satisfied with it, for one, I'm still mucking the attribute hashes from the caller directly which requires understanding of how the logic works for these hashes (:id set or not set, for instance), and two, I'm calling a function that is not trivial to fit here. It would be nice if there are ways to tell 'accepts_nested_attributes_for' to only create new record when certain condition is not met. The one-to-one association has a :update_only flag that does something similar but this is lacking for one-to-many relationship.
Are there better solutions out there?
This kind of logic probably belongs in your model, not your controller. I'd consider re-writing the author_attributes= method that is created by default for your association.
def authors_attributes=(authors_attributes)
authors_attributes.values.each do |author_attributes|
author_to_update = Author.find_by_id(author_attributes[:id]) || Author.find_by_username(author_attributes[:username]) || self.authors.build
author_to_update.update_attributes(author_attributes)
end
end
I haven't tested that code, but I think that should work.
EDIT: To retain the other functionality of accepts_nested_Attributes_for, you could use super:
def authors_attributes=(authors_attributes)
authors_attributes.each do |key, author_attributes|
authors_attributes[key][:id] = Author.find_by_username(author_attributes[:username]).id if author_attributes[:username] && !author_attributes[:username].present?
end
super(authors_attributes)
end
If that implementation with super doesn't work, you probably have two options: continue with the 'processing' of the attributes hash in the controller (but turn it into a private method of your controller to clean it up a bit), or continue with my first solution by adding in the functionality you've lost from :destroy => true and reject_if with your own code (which wouldn't be too hard to do). I'd probably go with the first option.
I'd suggest using a form object instead of trying to get accepts_nested_attributes to work. I find that form object are often much cleaner and much more flexible. Check out this railscast
I have an admittedly ugly query to do, to find a particular role related to the current role. This line produces the correct result:
#person_event_role.event_role.event.event_roles.
joins(:mission_role).where(:mission_roles => {:title => 'Boss'}).
first.person_event_roles.first.person
(You can infer the associations from the plurality of those calls)
The only way to get this information requires a ton of knowledge of the structure of the database, but to remove the coupling... It would require filling in a bunch of helper functions in each step of that chain to give back the needed info...
I think the thing to do here is to create the helper functions where appropriate. I'm unclear what the beginning of your association chain is here, but I'd probably assign it a method #event that returns event_role.event. From there, an event has an #boss_role, or whatever makes sense semantically, and that method is
event_roles.joins(:mission_role).where(:mission_roles => {:title => 'Boss'}).first
Finally, also on the Event model, there's a #boss method, which gets
boss_roles.first.person_event_roles.first.person
So, your original query becomes
#person_event_role.event.boss
Each leg of the chain is then self-contained and easy to understand, and it doesn't require the beginning of your chain to be omniscient about the end of it. I don't fully comprehend the full reach of these associations, but I'm pretty sure that just breaking it into three or four model methods will give you the clean reading and separation of concerns you're looking for. You might even break it down further for additional ease of reading, but that becomes a question of style.
Hope that helps!
The following is by the original questioner
I think I followed this advice and ended up with:
#person_event_role.get_related_event_roles_for('Boss').first.filled_by.first
#person_event_role:
def get_related_event_roles_for(role)
event.event_roles_for(role)
end
def event
event_role.event
end
#event:
def event_roles_for(role)
event_roles.for_role(role)
end
#event_role:
scope :for_role, lambda {|role| joins(:mission_role).where(:mission_roles => {:title => role})}
def filled_by
person_event_roles.collect {|per| per.person}
end