Through a after_create callback I'm trying to assign a User a Program_id though a join model, and assign initial values for three additional parameters in that same join model.
Assigning the program_id works fine, I can't figure out how to add the additional parameters.
class User < ActiveRecord::Base
after_create :assign_user_program, :add_initial_programs
def assign_user_program
self.programs = Program.for_user(self)
end
class Program < ActiveRecord:Base
def self.for_user(user)
where(:goal_id => user.goal_id, :experience_id => user.experience_level_id, :gender => user.gender)
end
I tried creating another method in the after_create to assign the other three parameters, but that just creates another record in the join model with the three parameters assigned, and no program_id
def add_initial_programs
self.user_programs.create(:cycle_order => 1, :group_order => 1, :workout_order => 1)
end
Any ideas on how I can simply update the record that was just created?
EDIT:
To clarify, I'm trying to create one record in the join table with the program_id, user_id, group_order, cycle_order, and workout_order, as shown in the picture:
What is happening is that I'm getting two records, one with a program_id, and one with no program_id, but the other values assigned. See picture below:
You should probably run your callback before_create instead of after_create so the extra attributes get set on the model before it's persisted to the database. Doing it after_create means you'll end up sending two queries (one CREATE and one UPDATE) instead of one CREATE.
class User < ActiveRecord::Base
before_create :assign_user_program, :add_initial_programs
protected
def assign_user_program
self.programs = Program.for_user(self)
end
def add_initial_programs
self.user_programs.build(:cycle_order => 1, :group_order => 1, :workout_order => 1)
end
end
If you really want to do it in after_create, you'll have to call save or save! on the user model to actually persist the attribute changes to the database.
So the answer here was actually quite simple. I needed to put all the logic into one method like this:
def add_initial_program
prog_id = Program.for_user(self).first.id
self.user_programs.build( :cycle_order => 1, :group_order => 1, :workout_order => 1, :program_id => prog_id)
end
Which created the desired result of giving a user a program, and assigning the other values I needed.
Related
Could not find nothing close to what I'm trying to do. I want to store an object into a user's column. That column is in the form of an array:
#postgres
def change
add_column :users, :interest, :string, array: true, default: '{}'
end
I have another model called FooBar setup for other use. Each user has unique information inside as I've added a user_id key.
Im trying to make more sense:
def interest
#user = User.find(current_user.id ) # I need the logged in user's id
#support = Support.find(params[:id]) # I need the post's id they are on
u = FooBar.new
u.user_id = #user
u.support_id = #support
u.save # This saves a new Foo object..this is what I want
#user.interest.push(FooBar.find(#user)) # This just stores the object name itself ;)
end
So when I call u1 = FooBar.find(1) I get value return in hash. I want when I say u1.interest I get the same. The reason is, I need to target those keys on the user ie: u1.interest[0].support_id
Is this possible? I've looked over my basic ruby docs and nothing works. Oh..if I passed FooBar.find(#user).inspect I get the hash but not the way I want it.
Im trying to do something similar to stripe. Look at their data key. That's a hash.
Edit for Rich' answer:
I have, literally, a model called UserInterestSent model and table:
class UserInterestSent < ActiveRecord::Base
belongs_to :user
belongs_to :support # you can call this post
end
class CreateUserInterestSents < ActiveRecord::Migration
def change
create_table :user_interest_sents do |t|
t.integer :user_id # user's unique id to associate with post (support)
t.integer :interest_sent, :default => 0 # this will manually set to 1
t.integer :support_id, :default => 0 # id of the post they're on
t.timestamps # I need the time it was sent/requested for each user
end
end
end
I call interest interest_already_sent:
supports_controller.rb:
def interest_already_sent
support = Support.find(params[:id])
u = UserInterestSent.new(
{
'interest_sent' => 1, # they can only send one per support (post)
'user_id' => current_user.id, # here I add the current user
'support_id' => support.id, # and the post id they're on
})
current_user.interest << u # somewhere this inserts twice with different timestamps
end
And the interest not interests, column:
class AddInterestToUsers < ActiveRecord::Migration
def change
add_column :users, :interest, :text
end
end
HStore
I remembered there's a PGSQL datatype called hStore:
This module implements the hstore data type for storing sets of
key/value pairs within a single PostgreSQL value. This can be useful
in various scenarios, such as rows with many attributes that are
rarely examined, or semi-structured data. Keys and values are simply
text strings.
Heroku supports it and I've seen it used on another live application I was observing.
It won't store your object in the same way as Stripe's data attribute (for that, you'll just need to use text and save the object itself), but you can store a series of key:value pairs (JSON).
I've never used it before, but I'd imagine you can send a JSON object to the column, and it will allow you to to use the attributes you need. There's a good tutorial here, and Rails documentation here:
# app/models/profile.rb
class Profile < ActiveRecord::Base
end
Profile.create(settings: { "color" => "blue", "resolution" => "800x600" })
profile = Profile.first
profile.settings # => {"color"=>"blue", "resolution"=>"800x600"}
profile.settings = {"color" => "yellow", "resolution" => "1280x1024"}
profile.save!
--
This means you should be able to just pass JSON objects to your hstore column:
#app/controllers/profiles_controller.rb
class ProfilesController < ApplicationController
def update
#profile = current_user.profile
#profile.update profile_params
end
private
def profile_params
params.require(:profile).permit(:x, :y, :z) #-> z = {"color": "blue", "weight": "heavy"}
end
end
As per your comments, it seems to me that you're trying to store "interest" in a User from another model.
My first interpretation was that you wanted to store a hash of information in your #user.interests column. Maybe you'd have {name: "interest", type: "sport"} or something.
From your comments, it seems like you're wanting to store associated objects/data in this column. If this is the case, the way you're doing it should be to use an ActiveRecord association.
If you don't know what this is, it's essentially a way to connect two or more models together through foreign keys in your DB. The way you set it up will determine what you can store & how...
#app/models/user.rb
class User < ActiveRecord::Base
has_and_belongs_to_many :interests,
class_name: "Support",
join_table: :users_supports,
foreign_key: :user_id,
association_foreign_key: :support_id
end
#app/models/support.rb
class Support < ActiveRecord::Base
has_and_belongs_to_many :users,
class_name: "Support",
join_table: :users_supports,
foreign_key: :support_id,
association_foreign_key: :user_id
end
#join table = users_supports (user_id, support_id)
by using this, you can populate the .interests or .users methods respectively:
#config/routes.rb
resources :supports do
post :interest #-> url.com/supports/:support_id/interest
end
#app/controllers/supports_controller.rb
class SupportsController < ApplicationController
def interest
#support = Support.find params[:support_id] # I need the post's id they are on
current_user.interests << #support
end
end
This will allow you to call #user.interests and bring back a collection of Support objects.
Okay, look.
What I suggested was an alternative to using interest column.
You seem to want to store a series of hashes for an associated model. This is exactly what many-to-many relationships are for.
The reason your data is being populated twice is because you're invoking it twice (u= is creating a record directly on the join model, and then you're inserting more data with <<).
I must add that in both instances, the correct behaviour is occurring; the join model is being populated, allowing you to call the associated objects.
What you're going for is something like this:
def interest_already_sent
support = Support.find params[:id]
current_user.interests << support
end
When using the method I recommended, get rid of the interest column.
You can call .interests through your join table.
When using the code above, it's telling Rails to insert the support object (IE support_id into the current_user (IE user_id) interests association (populated with the UserInterestSelf table).
This will basically then add a new record to this table with the user_id of current_user and the support_id of support.
EDIT
To store Hash into column, I suggest you to use "text" instead
def change
add_column :users, :interest, :text
end
and then set "serialize" to attribute
class User < ActiveRecord::Base
serialize :interest
end
once it's done, you can save hash object properly
def interest
#user = User.find(current_user.id ) # I need the logged in user's id
#support = Support.find(params[:id]) # I need the post's id they are on
u = FooBar.new
u.user_id = #user
u.support_id = #support
u.save # This saves a new Foo object..this is what I want
#user.interest = u.attributes # store hash
#user.save
end
To convert AR object to hash use object.attributes.
To store a custom hash in a model field you can use serialize or ActiveRecord::Store
You can also use to_json method as object.to_json
User.find(current_user.id ).to_json # gives a json string
I have a class student with has_many tests. The test class has a student_id, marks, name. Here the test name should be unique. The test is a nested attribute for student. So the parameters are this way:
:student => {:first_name => "abc",
:email => "dfsdf#sfdsdsd.bbb",
:tests_attributes => { "0" => {:name => "bgc", :marks => "470"}}}
I have a problem with update. If I update_attributes with the tests_attributes, it throws a validation error saying the name for test is not unique. I am actually addressing the same record here. How do I overcome this?
Without seeing your models (& validations), it's going to be quite difficult to diagnose your error directly.
--
Nested Attributes
We've done something like this, and found that your nested data is passed to the child model as if it were receiving a new object (without being nested). This means if you've got validates uniqueness for that model, it should be okay:
#app/models/test.rb
Class Test < ActiveRecord::Base
belongs_to :student
validates :name, uniqueness: true
end
Reason I write this is because there's a method called inverse_of, which basically allows you to access the parent model data in your child model
--
Update
I think the problem will likely lie with your use of update_attributes. Problem being you're trying to update both the student and the test attributes at one time.
I'm not sure exactly why this would be a problem, but I'd test this:
#app/controllers/students_controller.rb
class StudentsController < ApplicationController
def update
#student = Student.find params[:id]
#student.test.update(name: params[:test_name], marks: params[:marks])
end
end
I think if you can explain your methodology a little more, it will be much more helpful. I.E are you trying to update student or test? If you're updating student & adding a new test, how are you updating the studet?
Thanks for the reply guys. I ended up finding the answer myself. I did have a uniqueness validation for name.
I had a situation where initially I wouldn't know the student but have only his details. So I would have to create this hash and pass it to update. The trick to not trying to create a new record for the same name in test is to pass the actual record's ID along with it. This solved the problem
Nested Attributes
I think the problem with nested_attributes. For update need to pass nested_attributes with ID.
Ex.
:student => {:first_name => "abc",
:email => "dfsdf#sfdsdsd.bbb",
:tests_attributes => { "0" => {id: 1, :name => "bgc", :marks => "470"}}}
I have tried below-given example it is worked for me:
Update
#app/controllers/students_controller.rb
class StudentsController < ApplicationController
def update
#student = Student.find params[:id]
#student.update_attributes(student_params)
end
private
def student_params
params.require(:student).permit(:first_name, :email,
tests_attributes: [:id, :name, :marks])
end
end
I am pretty new to rails (and development) and have a requirement to create a change log. Let's say you have an employees table. On that table you have an employee reference number, a first name, and a last name. When either the first name or last name changes, I need to log it to a table somewhere for later reporting. I only need to log the change, so if employee ref 1 changes from Bill to Bob, then I need to put the reference number and first name into a table. The change table can have all the columns that mnight change, but most only be populated with the reference number and the changed field. I don't need the previous value either, just the new one. hope that makes sense.
Looked at gems such as paper trail, but they seem very complicated for what I need. I don't ever need to manipulate the model or move versions etc, I just need to track which fields have changed, when, and by whom.
I'd appreciate your recommendations.
If you insist on building your own changelog, based on your requirements you can do so using a few callbacks. First create your log table:
def up
create_table :employee_change_logs do |t|
t.references :employee
# as per your spec - copy all column definitions from your employees table
end
end
In your Employee model:
class Employee < ActiveRecord::Base
has_many :employee_change_logs
before_update :capture_changed_columns
after_update :log_changed_columns
# capture the changes before the update occurs
def capture_changed_columns
#changed_columns = changed
end
def log_changed_columns
return if #changed_columns.empty?
log_entry = employee_change_logs.build
#changed_columns.each{|c| log_entry.send(:"#{c}=", self.send(c))}
log_entry.save!
end
end
I recommend the gem vestal_versions.
To version an ActiveRecord model, simply add versioned to your class like so:
class User < ActiveRecord::Base
versioned
validates_presence_of :first_name, :last_name
def name
"#{first_name} #{last_name}"
end
end
And use like this:
#user.update_attributes(:last_name => "Jobs", :updated_by => "Tyler")
#user.version # => 2
#user.versions.last.user # => "Tyler"
The first thing we did was put an around filter in the application controller. This was how I get the current_employee into the employee model, which was the challenge, especially for a newbie like me!
around_filter :set_employee_for_log, :if => Proc.new { #current_account &&
#current_account.log_employee_changes? && #current_employee }
def set_employee_for_log
Thread.current[:current_employee] = #current_employee.id
begin
yield
ensure
Thread.current[:current_employee ] = nil
end
end
end
Next, in the employee model I defined which fields I was interested in monitoring
CHECK_FIELDS = ['first_name', 'last_name', 'middle_name']
then I added some hooks to actually capture the changes IF logging is enabled at the account level
before_update :capture_changed_columns
after_update :log_changed_columns, :if => Proc.new { self.account.log_employee_changes? }
def capture_changed_columns
#changed_columns = changed
#changes = changes
end
def log_changed_columns
e = EmployeeChangeLog.new
Employee::CHECK_FIELDS.each do |field|
if self.send("#{field}_changed?")
e.send("#{field}=", self.send(field))
end
end
if e.changed?
e.update_attribute(:account_id, self.account.id)
e.update_attribute(:employee_id, self.id)
e.update_attribute(:employee_ref, self.employee_ref)
e.update_attribute(:user_id, Thread.current[:current_employee])
e.save
else return
end
end
And that;s it. If the account enables it, the app keeps an eye on specific fields and then all changes to those fields are logged to a table, creating an simple audit trail.
How can I save (insert) only associated objects without saving (updating) the base object?
For example I just want to save the phone numbers, I don't wan to resave/update the person object.
def create_numbers
#params => person_id => 41, person => {:phone_number => '12343445, 1234566, 234886'}
#person = params[:person_id]
nums = params[:person][:phone_numbers].split(',')
nums.each do |num|
#person.phone_numbers.build(:number => num)
end
#person.save #here I just want to save the numbers, I don't want to save the person. It has read only attributes
end
Models:
Person < ...
# id, name
belongs_to :school, :class_name => :facility
has_many :phone_numbers
end
PhoneNumber < ...
# id, number
belongs_to :person
end
This is a bit of a dumb example, but it illustrates what I'm trying to accomplish
How about #person.phone_numbers.create(:number => num)
The downside is that you wont know whether it failed or not - you can handle that, but it depends on how exactly you want to handle it.
The simplest approach is to replace your build(:number => num) with create(:number => num), which will build and save the phone_number object immediately (assuming it passes validation).
If you need to save them all after creating the whole set (for some reason), you could just do something like
#person.phone_numbers.each{|num| num.save}
I have a data object which is composed_of three child instances of the same object. I need to calculate a value from that object and save it in the database. (It is later pulled form the db by another application.)
I've mocked out my class structure below, basically I want a method that will add together the Child values data_one and data_two, and store it into a third variable, total. Which I guess will be total_first, total_second and total_third in the db Parent table. Should I declare total as a Child attribute and use a callback to set it? Any help will be much appreciated - thank you! And apologies if this is a really obvious question...
class Child
attr_reader :data_one, :data_two
def initialize(data_one, data_two)
#data_one, #data_two,
end
def ==(other_child)
data_one == other_child.data_one &&
data_two == other_child.data_two
end
def Sdq.from_params(hash)
Sdq.new(
get_value(hash, :data_one),
get_value(hash, :data_two),
)
end
protected
def Sdq.get_value(hash, key)
hash.has_key?(key) ? hash[key] : hash[key.to_s]
end
end
class Parent < ActiveRecord::Base
composed_of :first_child, :class_name => "Child", :mapping => [
["data_one_first","data_one"],
["data_two_first","data_two"]
]
composed_of :second_child, :class_name => "Child", :mapping => [
["data_one_second","data_one"],
["data_two_second","data_two"]
]
composed_of :third_child, :class_name => "Child", :mapping => [
["data_one_third","data_one"],
["data_two_third","data_two"]
]
end
I can't imagine why a parent will always have exactly two children, why not a many_to_x relation? depending if you need many to many. Hopefully not seeing the example.
You must have your reasons.
I would use call backs like you described. Maybe before_validations and have some validation on it. Note, that returning a non-true value in a callback can result in the record not saving.
E.G If the condition is false, the method returns nil and can halt the save callback chain.
def before_save
if something_sometimes_is_false
#do normal code
end # could not run, which would return nil and break things
end
consider returning self at the end.
def before_save
if something_sometimes_is_false
# do normal code
end
self # should always be a true value in an instance of a class. will not break call backs
end