i have used public_activity gem in my app and also the act_as_follower gem
where a user can follow other user
the logic i am using to fetch all the following activities is
#follow_activities = PublicActivity::Activity.where(trackable_type: 'follow', key: 'follow.create')
here #follow_activities is fetching all the records where the following has been done but i want to limit this query,
It should fetch the follow activities only of those users which the current_user has followed.
fetching all queries is a bad idea.
for elaboration i am showing you the models i have included
class User< ActiveRecord::Base
acts_as_follower
acts_as_followable
end
and the follow model is as
class Follow < ActiveRecord::Base
include PublicActivity::Model
tracked owner: ->(controller, model) { controller && controller.current_user }
extend ActsAsFollower::FollowerLib
extend ActsAsFollower::FollowScopes
# NOTE: Follows belong to the "followable" interface, and also to followers
belongs_to :followable, :polymorphic => true
belongs_to :follower, :polymorphic => true
def block!
self.update_attribute(:blocked, true)
end
end
Please tell me how can i limit the records fetching. Thankx in advance
I finally figured it out i need to do this
follow_activities = PublicActivity::Activity.where(trackable_type: 'follow', key: 'follow.create', owner_id: current_user.all_following)
now this will fetch the records of only those users which the current_user has followed
I am using rails version 4.2 and ruby version 2.2.0. I am trying to save a record to lollypops table. No exceptions indicating reasons.
TASK: As soon as a member is created and saved, I want to populate the lollypops table by calling the create_lollypop(#member.id) in members controller's create method like this:
# POST /members
# POST /members.json
def create
#member = Member.create(members_params)
return unless request.post?
#member.save!
self.current_user = #member
c = Country.find(#member.country_id)
#member.update_attributes(
:country_code=>c.code)
create_lollypop(#member.id) #From here I want to create lollypop
MemberMailer.signup_notification(#member).deliver_now
redirect_to(:controller => '/admin/members', :action => 'show',
:id=> #member.id)
flash[:notice] = "Thanks for signing up! Check your email now to
confirm that your email is correct!"
rescue ActiveRecord::RecordInvalid
load_data
render :action => 'new'
end
def create_lollypop(member_id)
#member = Member.find(member_id)
Lollypop.create(
:member_id=>#member.id,
:product_name=>'lollypop',
:product_price=>100,
:email=>#member.email,
:house_flat => #member.house_flat,
:street=>#member.street,
:city_town=>#member.city_town,
:country =>#member.country,
:postcode_index=>#member.postcode_index,
:name=>#member.name)
end
The 'member' is created but the 'lollypops' table is not populated. The associations are:
MEMBER model:
has_one :lollypop, :dependent=>:destroy
LOLLYPOP model
belongs_to :member
If I use generic SQL command then the lollypops table gets populated but I do not want to do that:
def self.create_lollypop(member_id)
member = Member.find(member_id)
ActiveRecord::Base.connection.execute("insert into lollypops (member_id,product_name,product_price,email,house_flat,street,city_town,country,postcode_index,name)
values(#{member.id},'lollypop',#{100},'#{member.email}','#{member.house_flat}','#{member.street}','#{member.city_town}','#{member.country_code}','#{member.postcode_index}','#{member.name}')")
end
Any advice would be welcomed. Thank you.
In your create_lollypop(), You are not defining #member.
def create_lollypop(member_id)
#member = Member.find member_id
Lollypop.create!(
:member_id=>#member.id,
:product_name=>'lollypop',
:product_price=>100,
:email=>#member.email,
:house_flat => #member.house_flat,
:street=>#member.street,
:city_town=>#member.city_town,
:country =>#member.country,
:postcode_index=>#member.postcode_index,
:name=>#member.name
)
end
Also use create! so in case any validation failed then it will raise exception. So it will help you sort out issue.
For the moment try to create lollypop using the association method create_lollypop directly in your controller. use this code in you create controller method, note that create_lollypop method will fill (member_id field automatically):
#member = Member.create(members_params)
return unless request.post?
#member.save!
self.current_user = #member
c = Country.find(#member.country_id)
#member.update_attributes(
:country_code=>c.code)
#From here I want to create lollypop
#member.create_lollypop(
:product_name=>'lollypop',
:product_price=>100,
:email=>#member.email,
:house_flat => #member.house_flat,
:street=>#member.street,
:city_town=>#member.city_town,
:country =>#member.country,
:postcode_index=>#member.postcode_index,
:name=>#member.name
)
MemberMailer.signup_notification(#member).deliver_now
redirect_to(:controller => '/admin/members', :action => 'show',
:id=> #member.id)
flash[:notice] = "Thanks for signing up! Check your email now to
confirm that your email is correct!"
rescue ActiveRecord::RecordInvalid
load_data
render :action => 'new'
This is not exactly an answer, more like tips and notes, it's a little long and I hope you don't mind.
return unless request.post?
This is more of a php thing not a rails thing, in rails already the routing is checking this, so you don't need to do this check inside the controller, if it isn't a post it will be routed elsewhere.
#member = Member.create(members_params)
return unless request.post?
#member.save!
Saving after creating is meaningless, because create already saves the data, if you are doing it for the sake of the bang save!, then you could use the create with bang create!, not to mention that you do the redirection check after the member's create, so if this did work, it would leave you with stray members.
c = Country.find(#member.country_id)
#member.update_attributes(:country_code=>c.code)
If you have your assocciations correctly, you don't need to save the code like this, because the member knows that this country_id belongs to a country.
So add this to the member model
class Member < ActiveRecord::Base
has_one :lollypop, dependent: :destroy
belongs_to :country
end
This way you could always call #member.country to return the country object, then the code could come from there, like #member.country.code, or you could just write a method to shorten that up
def country_code
country.code
end
this way will get the code through an extra query, but it has an advantage, if you for any reason change a country's code, you don't need to loop on all members who have that country and update their codes too, you could also shorten this up even more using #delegate
#member.save!
#member.update_attributes(:country_code=>c.code)
Here you are updating the attributes of member after saving the member, which is kinda a waste, because you are doing 2 queries for what could be done with 1 query, programmatically it is correct and it will work, but it's bad for scaling, when more users start using your app the database will be more busy and the responses will be slower.
Instead i would recommend to postpone the creation of member till you have all the data you want
#member = Member.new(members_params) # this won't save to the database yet
#memeber.code = Country.find(#member.country_id).code
#member.save
This will only do 1 query at the end when all data is ready to be saved.
redirect_to(:controller => '/admin/members', :action => 'show', :id=> #member.id)
This is ok, but you probably have a better shorter path name in your routes, something like members_admin_path, check your routes name by doing a bin/rake routes in your terminal.
redirect_to members_admin_path(id: #member)
redirect_to ...
flash[:notice] = "message"
I'm not sure this will work, because the redirection needs to be returned, but when you added the flash after it, either the redirection will happen without the flash, or the flash will be set and returned as it's the last statement, but the redirection won't happen, not sure which will happen, to fix it you can simply swap the two statements, create the flash first and then redirect, or use the more convenient way of setting the flash while redirecting, cause that's supported
redirect_to ....., notice: 'my message'
rescue ActiveRecord::RecordInvalid
load_data
render :action => 'new'
This will do the job, but it isn't conventional, people tend to use the soft save and then do an if condition on the return value, either true or false, here's a short layout
# prepare #member's data
if #member.save
# set flash and redirect
else
load_data
render :new
end
The lollypop creation
Now there's a few things about this, first you have the method in the controller, which is bad cause it shouldn't be the controller's concern, the second method the self.create_lollypop is better cause it's created on the model level, but it's a class method, then the better way is creating it as a member method, this way the member who creates the lollypop already knows the data because it's his own self, notice i don't need to call #member because i am already inside member, so simple calls like id, email will return the member's data
# inside member.rb
def create_lollypop
Lollypop.create!(
member_id: id,
product_name: 'lollypop',
product_price: 100,
email: email,
house_flat: house_flat,
street: street,
city_town: city_town,
country: country,
postcode_index: postcode_index,
name: name
)
end
if you want you can also add this as an after create callback
after_create :create_lollypop
ps: This method name will probably conflict with the ActiveRecords create_lollypop method, so maybe you should pick a different name for this method.
As Mohammad had suggested to me, I changed Lollypop.create to Lollypop.create! and
while running my code, one validation error popped up. After correcting it and
altering my code to:
Lollypop.create!(
:member_id=> #member.id,
:product_name=>'lollypop',
:product_price=>100,
:email=>#member.email,
:house_flat => #member.house_flat,
:street=>#member.street,
:city_town=>#member.city_town,
:country =>#member.country_code,
:postcode_index=>#member.postcode_index,
:name=>#member.name
)
The 'lollypops' table got populated.
I have searched through all the active model serializer (v 0.9.0) documentation and SO questions I can find, but can't figure this out.
I have objects which can be marked as "published" or "draft". When they aren't published, only the user who created the object should be able to see it. I can obviously set permissions for "show" in my controller, but I also want to remove these objects from the json my "index" action returns unless it is the correct user. Is there a way to remove this object from the json returned by the serializer completely?
In my activemodel serializer, I am able to user filter(keys) and overloaded attributes to remove the data, as shown using my code below, but I can't just delete the entire object (I'm left having to return an empty {} in my json, trying to return nil breaks the serializer).
I'm probably missing something simple. Any help would be much appreciated!
class CompleteExampleSerializer < ExampleSerializer
attributes :id, :title
has_many :children
def attributes
data = super
(object.published? || object.user == scope || scope.admin?) ? data : {}
end
def filter(keys)
keys = super
(object.published? || object.user == scope || scope.admin?) ? keys : {}
end
end
That looks correct, try returning an array instead of a hash when you dont want any keys. Also, I don't think calling super is necessary b/c the filter takes in the keys.
Also, I don't think defining an attributes method is necessary.
I have chapters that can either be published or unpublished. They're owned by a story so I ended doing something like below.
has_many :unpublished_chapters, -> { where published: false }, :class_name => "Chapter", dependent: :destroy
has_many :published_chapters, -> { where published: true }, :class_name => "Chapter", dependent: :destroy
Inside of my serializer, I choose to include unpublished_chapters only if the current_user is the owner of those chapters. In ams 0.8.0 the syntax is like so.
def include_associations!
include! :published_chapters if ::Authorization::Story.include_published_chapters?(current_user,object,#options)
include! :unpublished_chapters if ::Authorization::Story.include_unpublished_chapters?(current_user,object,#options)
end
In my case, it's not so bad to differentiate the two and it saves me the trouble of dealing with it on the client. Our situations are similar but say you want to get all of the chapters by visiting the chapters index route. This doesn't make much sense in my app but you could go to that controller and render a query on that table.
I have a typical forum style app. There is a Topics model which has_many Posts.
What I want to do using Rails 2.3.x is query the topics table and sort by the most recent post in that topic.
#topics = Topic.paginate :page => params[:page], :per_page => 25,
:include => :posts, :order => 'HELP'
I'm sure this is a simple one but no joy with Google. Thanks.
Sorting on a joined column is probably a bad idea and will take an enormous amount of time to run in many situations. What would be better is to twiddle a special date field on the Topic model when a new Post is created:
class Post < ActiveRecord::Base
after_create :update_topic_activity_at
protected
def update_topic_activity_at
Topic.update_all({ :activity_at => Time.now }, { :id => self.topic_id})
end
end
Then you can easily sort on the activity_at column as required.
When adding this column you can always populate the initial activity_at with the highest posting time if you have existing data to migrate.
I'm trying to implement Ryan Bates' sortable table columns code (Railscast #228) but I'd like to be able to sort on an associated column. In particular, I have the following models and associations:
class Project < ActiveRecord::Base
belongs_to :program_manager, :class_name => "User"
class User < ActiveRecord::Base
has_many :program_manager_projects, :class_name => "Project", :foreign_key => "program_manager_id"
The association between the Project model and the User model is mediated by the 'program_manager_id' foreign key, which the user sets in the new/edit views using a collection-select dropdown. Here's part of the annotation at the top of project.rb:
# Table name: projects
# program_manager_id :integer
I want to be able to sort my list of projects in the index view by the program manager's name, i.e., by project.program_manager.name.
Ideally, I'd be able to point :order to this name somehow, perhaps with something like this in the index method of my ProjectsController:
#projects = Project.find(:all, :order => project.program_manager.name)
But that obviously won't work (not to mention Ryan's routine implements this with a specific reference to table names from the model to be sorted.)
I've come across some intimidating approaches that use named_scope, such as:
named_scope :most_active, :select => "questions.*", :joins => "left join comments as comments_for_count on comments_for_count.question.id = questions.id", :group => "questions.id", :order => "count(questions.id) desc"
But given my lack of MySQL expertise, this is fairly impenetrable to me.
Can anyone help me either generalize the named_scope example above for my specific case, or point me to a more straightforward strategy?
Thanks very much,
Dean
Let's dissect that named scope you referenced above. Imagine a model Question which has many Comments.
named_scope :most_active, :select => "questions.*", :joins => "left join comments as comments_for_count on comments_for_count.question.id = questions.id", :group => "questions.id", :order => "count(questions.id) desc"
:most_active
the name of your scope. You would reference thusly: Question.find(:all).most_active
:select => "questions.*"
by default scopes selects all columns from your table anyway, so this limits the results to only the questions table, and not the comments table. This is optional.
:joins => "left join comments as comments_for_count on comments_for_count.question.id = questions.id"
this is saying for every question, I also want to get all comments associated with them. The comments table has a column 'question_id' which is what we'll be using to match them up to the appropriate question record. This is important. It allows us access to fields that are not on our model!
:group => "questions.id"
This is required for the count() function in the order clause to tell us that we want the count of comments based on question. We don't need the count function in our order clause, so we also don't need this group statement
:order => "count(questions.id) desc"
Return the results in order of number of comments, highest to lowest.
So for our example, discarding what we don't need, and applying to your needs, we end up with:
:named_scope :by_program_manager_name, :joins => "left join users on projects.program_manager_id = users.id", :order => "users.name"
This named_scope would be called thusly:
Project.find(:all).by_program_manager_name
Note this is basically equivalent to:
Project.find(:all, :joins => "left join users on projects.program_manager_id = users.id", :order => "users.name")
But, as cam referenced above, you should really know the underlying SQL. Your abilities will be severely hampered without this understanding