How to chain search params and use them as objects? - ruby-on-rails

Question

In my project I have a department model. I want to add employees to the department by using a search. I want to add the result of the search to a list, then submit the list and add all searched employees in one go at the end, all in the same view.
Search function in departments_controller
def add_employees
employees = Employee.all
#searched_employee = Employee.where('name LIKE ?', "#{params[:search_by_name]}")
#searched_employee.each do |employee|
#searched_employee_name = employee.name
end
end
add_employees-view:
h1 Add employees
= form_for #department, :url => add_employees_path(:param1 => #searched_employee_name, :param2 => request.query_parameters), method: :post do
= label_tag :search_by_name
br
= search_field_tag :search_by_name, params[:name]
= submit_tag "Search"
= form_for #department, :url => add_employee_path, html: {method: "post"} do |f|
- if params[:search_by_name].present?
- #searched_employee.each do |employee|
li = employee.name
br
table
h5 Employees
thead
tr Name
tr Email
tbody
- #searched_employee.each do |employee|
tr
td = employee.name
td = request.query_parameters
Single search works fine, so I hoped to add a second param which stores the first request to be passed on for the next search and so forth.
Now I am stuck with splitting up the long query string into its unique search results and their objects, as to add them to a list where I can then work further with them (checkboxes etc).
Request.query_parameters is nested, but does not react to dig, because it says it is a string.
Any ideas on how to approach this or maybe a better solution, without the use of additional gems?

Answer 1

Here is how I would solve it if I had to do it without JS.
Create an M-2-M association with a join model between deparments and employees. Let departments accept nested attributes for the join model:
class Department < ApplicationRecord
has_many :positions
has_many :employees, through: :positions
accepts_nested_attributes_for :positions, reject_if: :reject_position?
private
def reject_position?(attributes)
!ActiveModel::Type::Boolean.new.cast(attributes['_keep'])
end
end
class Employee < ApplicationRecord
has_many :departments
has_many :positions, through: :departments
end
# rails g model position employee:belongs_to department:belongs_to
class Position < ApplicationRecord
belongs_to :employee
belongs_to :department
attribute :_keep, :boolean
end
Setup the routes:
# config/routes.rb
Rails.application.routes.draw do
# ...
# #todo merge this with your existing routes
resources :departments, only: [] do
resources :employees, only: [], module: :departments do
collection do
get :search
patch '/',
action: :update_collection,
as: :update
end
end
end
end
Now lets create the search form:
# /app/views/departments/employees/search.rb
<%= form_with(
url: search_department_employees_path(#department),
local: true,
method: :get
) do |form| %>
<div class="field">
<%= form.label :search_by_name %>
<%= form.text_field :search_by_name %>
</div>
<% #results&.each do |employee| %>
<%= hidden_field_tag('stored_employee_ids[]', employee.id) %>
<% end %>
<%= form.submit("Search") %>
<% end %>
Note that we are using GET instead of POST. Since this action is idempotent (it does not actually alter anything) you can use GET.
Note <%= hidden_field_tag('stored_employee_ids[]', employee.id) %>. Rack will merge any pairs where the key ends with [] into an array.
Now lets setup the controller:
module Departments
# Controller that handles employees on a per department level
class EmployeesController < ApplicationController
before_action :set_department
# Search employees by name
# This route is nested in the department since we want to exclude employees
# that belong to the department
# GET /departments/1/employees?search_by_name=john
def search
#search_term = params[:search_by_name]
#stored_ids = params[:stored_employee_ids]
if #search_term.present?
#results = not_employed.where('employees.name LIKE ?', #search_term)
end
# merge the search results with the "stored" employee ids we are passing along
if #stored_ids.present?
#results = not_employed.or(Employee.where(id: #stored_ids))
end
#positions = (#results||[]).map do |employee|
Position.new(employee: employee)
end
end
private
def not_employed
#results ||= Employee.where.not(id: #department.employees)
end
def set_department
#department = Department.find(params[:department_id])
end
end
end
This just creates a form that "loops back on itself" and just keeps adding more ids to the query string - without all that hackery.
Now lets create a second form where we actually do something with the search results as a partial:
# app/views/departments/employees/_update_collection_form.html.erb
<%= form_with(
model: #department,
url: update_department_employees_path(#department),
local: true,
method: :patch
) do |form |%>
<legend>Add to <%= form.object.name %></legend>
<table>
<thead>
<tr>
<td>Add?</td>
<td>Name</td>
<tr>
</thead>
<tbody>
<%= form.fields_for(:positions, #positions) do |p_fields| %>
<tr>
<td>
<%= p_fields.label :_keep, class: 'aria-hidden' %>
<%= p_fields.check_box :_keep %>
</td>
<td>
<%= p_fields.object.employee.name %>
<%= p_fields.hidden_field :employee_id %>
</td>
</tr>
<% end %>
</tbody>
</table>
<%= form.submit 'Add employees to department' %>
<% end %>
form.fields_for(:positions, #positions) loops through the array and creates inputs for each position.
And render the partial in app/views/departments/employees/search.html.erb:
# ...
<%= render partial: 'update_collection_form' if #positions.any? %>
You should not nest this form inside another form. That will result in invalid HTML and will not work properly.
Unlike your solution I'm not cramming everything and the bathtub into a single endoint. This form sends a PATCH request to /departments/1/employees. Using PATCH on an entire collection like this is somewhat rare as we usually just use it for individual members. But here we really are adding a bunch of stuff to the collection itself.
Now lets add the action to the controller:
module Departments
# Controller that handles employees on a per department level
class EmployeesController < ApplicationController
# ...
# Adds a bunch of employees to a department
# PATCH /departments/:department_id/employees
def update_collection
if #department.update(nested_attributes)
redirect_to action: :search,
flash: 'Employees added'
else
#postions = #department.positions.select(&:new_record?)
render :search,
flash: 'Some employees could not be added'
end
end
private
# ...
def update_collection_attributes
params.require(:department)
.permit(
positions_attributes: [
:keep,
:employee_id
]
)
end
end
end
There is almost nothing to it since accepts_nested_attributes is doing all the work on the controller layer.
I'll leave it up to you to convert this ERB to Slim or Haml and adapt it to your existing code base.

Answer 2

So, if anyone faces a similar problem, what I cam up with is this:
- Hash[CGI::parse(request.query_string).map{|k,v| [k,v]}].values.each do |value|
- valuename = value[0]
- employees = Employee.all
- found_employees = employees.where('name LIKE ?', "#{valuename}")
- found_employees.each do |employee|
tr
td = employee.name
First line: gets the whole query string, parses over it to look for the parameters and puts them in a hash, then reads out the key value pairs, which then are arrays. Those arrays' values are then iterated over.
Second line: since the values are still in an array, I ask the arrays to just put out the pure values with value[0], and assign them to valuename.
Folowing lines: Just querying the database to find all employee-names that match a valuename, receive objects so I can further work on them.