Building dynamc queries in rails 3 - ruby-on-rails-3

Question

I have been struggling far too long on this one. I have a fairly complex query that I have pieced together, but it seems to me to be way too verbose and ugly.
I have an advanced tickets search form that has 8 different search fields, plus created_at and updated_at search options in which users can choose the day, month, and/or year to filter their results.
I am building query conditions in my tickets_controller like this.
conditions = String.new
arguments = []
unless params[:id].blank?
conditions << ' AND ' unless conditions.length == 0
conditions << 'tickets.id = ?'
arguments << params[:id]
end
unless params[:organization].blank?
conditions << ' AND ' unless conditions.length == 0
conditions << 'organizations.name ILIKE ?'
arguments << "%#{params[:organization]}%"
end
unless params[:keywords].blank?
conditions << ' AND ' unless conditions.length == 0
conditions << 'subject ILIKE ?'
arguments << "%#{params[:keywords]}%"
end
unless params[:status_id].blank?
conditions << ' AND ' unless conditions.length == 0
conditions << 'status_id = ?'
arguments << params[:status_id]
end
unless params[:resolution_status_id].blank?
conditions << ' AND ' unless conditions.length == 0
conditions << 'resolution_status_id = ?'
arguments << params[:resolution_status_id]
end
unless params[:priority_id].blank?
conditions << ' AND ' unless conditions.length == 0
conditions << 'priority_id = ?'
arguments << params[:priority_id]
end
unless params[:assigned_to_id].blank?
conditions << ' AND ' unless conditions.length == 0
conditions << 'assigned_to_id = ?'
arguments << params[:assigned_to_id]
end
#tickets = Ticket.joins(:organization).where(conditions, arguments).paginate(:page => params[:page], :per_page => 20).order("updated_at DESC")
It gets confusing for me on fields that have special joins. For example, I have and email column on another table and have created a separate method in tickets.rb that looks like this.
def self.email(email)
joins('LEFT OUTER JOIN assignments ON assignments.person_id = tickets.owner_id').where('assignments.email_address ILIKE ?', email)
end
then call it with a terinary like this
params[:email].blank? ? nil : #tickets = #tickets.email("%#{params[:email]}%")
I also have a contact search field that searches both the first name, and last name of my people table. I created a seperate method that looks like this...
def self.contact(contact)
joins('LEFT OUTER JOIN people ON people.user_id = tickets.owner_id').where('people.last ILIKE ? OR people.first ILIKE ?', contact, contact)
end
Then call it in another terinary as I did with the params[:email].
This really doesn't seem like the best way to go about it to me, but I am new to programming and haven't been able to come up with anything more elegant. I have a number or these terniary operators that are building up my query, and while it is working just fine, I can't help but feel like I'm doing something wrong here.
I hope this is enough information to go on, if not I can clarify when needed.

Answer 1

It seems to me that you are doing manually all of ActiveRecord's job.
I would have a scope for each of your cases:
eg:
#class Ticket < ActiveRecord::Base
scope :with_subject lambda { |keyword| where('subject ILIKE ?', keyword) }
scope :with_status_id { |s_id| where(status_id: s_id) }
which will be used as follows:
#tickets = Ticket.scoped
#tickets = #tickets.with_subject(params[:keywords]) unless params[:keywords].blank?
#tickets = #tickets.with_status_id(params[:status_id]) if params[:status_id].present?
the joins can be also chained in AR syntax
#tickets = #tickets.joins('LEFT OUTER JOIN people ON people.user_id = tickets.owner_id')
The only problem is the use of OR clauses, which IMO are more readable in the SQL syntax
where('people.last ILIKE ? OR people.first ILIKE ?', contact, contact)
Hope it helps.
PS: You can find more on the subject on the relevant Rails guide