Stephen Sizer

Does anyone know of any good tutorials showing how to add filters for searching?

Thanks in advance.

I have a Lesson model that has an order field of type integer. What i want to do is find the previous lesson.

Lesson.where("order < ?" , 8)

This causes the following error. Any help would be appreciated.

Lesson Load (1.9ms) SELECT "lessons".* FROM "lessons" WHERE (order < 8) LIMIT $1 [["LIMIT", 11]]
ActiveRecord::StatementInvalid: PG::SyntaxError: ERROR: syntax error at or near "order"
LINE 1: SELECT "lessons".* FROM "lessons" WHERE (order < 8) LIMIT...
^
: SELECT "lessons".* FROM "lessons" WHERE (order < 8) LIMIT $1

I am currently building an LMS and am looking to add in the ability for the user to navigate to the next lesson.

In the admin back end when a teacher adds a lesson they are able to give it a position, this helps lay the lessons out. I sort on both position and then by title. So the learner can see the whole list of lessons, including topics within a lesson.

Now when the user views a lesson, I want to have the functionality for the learner to be able to click next lesson button. This will mark the current lesson as viewed and also navigate to the next lesson.

What is the best way to go about this?

I have looked and have seen the following suggestions

@next_lesson = @course.lessons.where("position > ?", @lesson.position).order(:position).first

This will work as long as every lesson has a unique position set. Sometimes this may not be the case, imagine a scenario where the teacher thinks of a lesson which would be better suited to the start of the course and he wants to add this to the beginning adding the postion of 2 this would fail as there is already a lesson with this value. Would they then need to change every lesson position value to add this position in?

Not sure what the best way to do this would be? Suggestions are welcome, especially if I have missed something very obvious.

Models for Course, Lesson and Topic are shown below, but this is just standard stuff.

class Course < ApplicationRecord
  belongs_to :author, class_name: 'User', foreign_key: 'author_id'
  has_many :lessons
end

class Lesson < ApplicationRecord
  belongs_to :author, class_name: 'User', foreign_key: 'author_id'
  belongs_to :course
  has_many :topics
end

class Topic < ApplicationRecord
  belongs_to :author, class_name: 'User', foreign_key: 'author_id'
  belongs_to :lesson
end

This is correct :)

Hi Jack,

Thanks for the reply.

that code would work for a project being 2 weeks old. Some projects may run for a year and i want to run some code every week.

To give you more context...

Every week I want to create a review for the project. So after 1 whole week a review gets created for the project manager to fill out. After 2 weeks, 3 weeks, 4 weeks ... 27 weeks and so on until the project finishes.

Thanks,
Steve

I have a project model with a start and end date.

I want to bring back all pojects that are exactly a week old, 2 weeks, 3 weeks etc

Is there a way to do this using a scope?

Thanks in advance

Great Video!!

I would love to use this with a population density overlay.. does anyone know where I can get that data?

Hi Jacob,

Thanks for your comment. You can indeed get tenders that have been assigned to the Contractor through the method above but this is just for those assigned to them directly and not indirectly through groups they belong to.

You can do this seperately via the ContractorDetail.find(contractor).tenders_by_group, I suppose I was wondering what would be the best way to combine these?

I have a method (not yet a scope) that I was playing with on the Tender model just to see if it worked.

def all_tenders
all = self.tenders
all << self.tenders_by_group
all.uniq
end

Is this the most efficient way?

I am trying to write an internal tender application and am having trouble figuring out the best approach for writing a scope.

I have the following models

class Tender < ApplicationRecord
  belongs_to :user
  belongs_to :company_detail
  has_many :questions
  has_many :assets
  has_many :tender_groups, dependent: :destroy
  has_many :groups, through: :tender_groups
  has_many :tender_contractors, dependent: :destroy
  has_many :contractor_details, through: :tender_contractors
  has_many :bids
  has_many :contractor_details_from_groups, through: :groups, source: :contractor_details

  accepts_nested_attributes_for :tender_groups
  accepts_nested_attributes_for :tender_contractors
  accepts_nested_attributes_for :assets

  validates :title, :length_days, :summary, presence: true

  scope :live, ->{ where( "tender_end_date > ?", Time.current ) }
  scope :all_public, ->{ where( public: true ) }

end

class ContractorDetail < ApplicationRecord

  filterrific :default_filter_params => { :sorted_by => 'business_name_asc' },
    :available_filters => %w[
      sorted_by
      search_query
      with_business_type_id
    ]


  self.per_page = 10

  has_many :users
  has_many :insurances
  has_many :ratings
  has_many :issues
  belongs_to :business_type
  has_and_belongs_to_many :projects
  has_one :address, as: :addressable
  has_one :pre_qualify_info
  has_many :references
  has_many :bids
  has_many :group_contractors
  has_many :groups, through: :group_contractors
  has_many :tender_contractors
  has_many :tenders, through: :tender_contractors
  has_many :tenders_by_group, through: :groups, source: :tenders

  scope :search_query, lambda { |query|
    return nil  if query.blank?
    # condition query, parse into individual keywords
    terms = query.downcase.split(/\s+/)
    # replace "*" with "%" for wildcard searches,
    # append '%', remove duplicate '%'s
    terms = terms.map { |e|
      (e.gsub('*', '%') + '%').gsub(/%+/, '%')
    }
    # configure number of OR conditions for provision
    # of interpolation arguments. Adjust this if you
    # change the number of OR conditions.
    num_or_conditions = 2
    where(
      terms.map {
        or_clauses = [
          "LOWER(contractor_details.business_name) LIKE ?",
          "LOWER(contractor_details.contact_email) LIKE ?"
        ].join(' OR ')
        "(#{ or_clauses })"
      }.join(' AND '),
      *terms.map { |e| [e] * num_or_conditions }.flatten
    )
  }

  scope :sorted_by, lambda { |sort_option|
    # extract the sort direction from the param value.
    direction = (sort_option =~ /desc$/) ? 'desc' : 'asc'
    case sort_option.to_s
    when /^business_name_/
      # Simple sort on the name colums
      order("LOWER(contractor_details.business_name) #{ direction }")
    else
      raise(ArgumentError, "Invalid sort option: #{ sort_option.inspect }")
    end
  }

  scope :with_business_type_id, lambda { |business_type_ids|
    where(:business_type_id => [*business_type_ids])
  }

  def all_tenders
    all = self.tenders
    all << self.tenders_by_group
    all.uniq
  end

  # This method provides select options for the `sorted_by` filter select input.
  # It is called in the controller as part of `initialize_filterrific`.
  def self.options_for_sorted_by
    [
      ['Name (a-z)', 'business_name_asc'],
      ['Name (z-a)', 'business_name_desc'],
      ['Business Type (a-z)', 'business_type_name_asc']
    ]
  end

  def contact_fullname
    "#{contact_first_name} #{contact_last_name}"
  end

  end

Some information on how tenders work:

Tenders can be public viewable by all contractors
Tenders have a end date (tender_end_date) where they are no longer visible to contractors

Contractors can be added to tenders via the tender_contractors (many to many)
Contractors can also be added to groups to then allow mass assignment to a tender by groups (tender_groups)

What I am looking at doing is writing a scope to pull back all tenders assigned to a given contractor that are live (not past the tender_end_date). The should include public tenders.

Should I seperate these out into individual scopes live I have started to? Public and Live, so that these can be used on their own or chained to give me exactly what I need.

Also how would I go about writing the scope to find the tenders assigned to the contractor, would this need to be written in sql?

If more detail is needed please let me know.

Thanks in advance for taking your time to look at this. I am still learning my craft.

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Hi I have 2 models Tender and Group shown below.

For a Tender you can add Contractors (contractor_details) and you can also add Groups (groups). Groups also contain contractor_details.

This is so that they may want to categorize certain contractors they use alot into specific groups by speciality e.g. Joiners, Electrians e.t.c..

What would the best way for me to check all contractors added to a tender including through groups, this is so that I can then do authorization and only allow those contractors added to view the tender page?

class Group < ApplicationRecord
  belongs_to :company_detail
  has_many :group_contractors, dependent: :destroy
  has_many :contractor_details, through: :group_contractors
  has_many :tender_groups
  has_many :tenders, through: :tender_groups

  accepts_nested_attributes_for :group_contractors

  validates :name, presence: true
end

class Tender < ApplicationRecord
  belongs_to :user
  belongs_to :company_detail
  has_many :questions
  has_many :assets
  has_many :tender_groups, dependent: :destroy
  has_many :groups, through: :tender_groups
  has_many :tender_contractors, dependent: :destroy
  has_many :contractor_details, through: :tender_contractors
  has_many :bids

  accepts_nested_attributes_for :tender_groups
  accepts_nested_attributes_for :tender_contractors
  accepts_nested_attributes_for :assets

  validates :title, :length_days, :summary, presence: true  

end

Hi,
I've got a system where users upload documents with expiry dates. I want to send the user an email reminder 1 month and 1 week before expiration to remind them to upload a new document.

What's the best way to do this?

Thanks in advance.
Steve

Thanks for the super speedy response :)

Hi,

I have currently two Devise models Company and Contractor.

When they sign in I want to redirect them to a dashboard page. At the moment I have a before_action on the dashboard controller that only allows authenticate_company! so when a contractor signs in they can't view the dashboard.

Anyone done something like this before? Also is there an easy way to check which user is currently logged in so that I can show them different partial views?

Thanks in advance