I have multiple controllers. and I have a method to filter like this.
def filter(filtering_params)
results = where(nil)
filtering_params.each do |key, value|
results = results.public_send(key, value) if value.present?
end
results
end
and from controllers, I will call index or show APIs using filtering params for example like this.
def filtering_params
params.slice(:status, :created_at, :id, :transaction_datetime, :portfolio_external_reference_id, :file_id, :file_name)
end
which I will use while fetching from API like this.
def index
records = Module::Class.filter(filtering_params)
render json: {
data: records
}
end
I want to write a generic method that can be used in cases where I want all the available attributes in the particular model as the filtering_params. is there any better way than writing all the attributes?
I solved it and it's working for me.
def filter_params(params)
values = params.slice(*column_names.map(&:to_sym))
filter(values)
end
Related
I have model Places and I have the index method in a controller. I need to get all places via request
/places
And filter places via request with query
/places?tlat=xxxx&tlong=xxxx&blat=xxxxx&blong=xxxx
What the best way to get this records? Should I check an existence of each param or are there Rails way?
#places = if params[tlat]&¶ms[blat]....
Places.all.where("lat > ? AND long > ? AND lat < ? AND long < ?", tlat, tlong, blat, blong)
else
Places.all
If you want to set WHERE clauses depending on params, you can use Ursus' code which is fine.
However, if you need to apply those WHERE clauses only if a set of params are present, you can use the following:
#places = Place.all
if params[:blat].present? && params[:tlat].present?
#places = #places.where(blat: params[:blat], tlat: params[:tlat])
end
# etc.
You could use an array of arrays to pair the associated params, kind of like what Ursus did.
I'd do something like this if possible. Important to note the this is just one query, composed dynamically.
#places = Place.all
%i(tlat tlong blat blong).each do |field|
if params[field].present?
#places = #places.where(field => params[field])
end
end
IMO, truly the "Rails way" (but actually just the "Ruby way") would be to extract this long conditional, and the query itself, out to their own private method. It becomes much easier to understand what's going on in the index action
class MyController < ApplicationController
def index
#places = Place.all
apply_geo_scope if geo_params_present?
end
private
def geo_params_present?
!!(params[:tlat] && params[:blat] && params[:tlong] && params[:blong])
end
# A scope in the model would be better than defining this in the controller
def apply_geo_scope
%i(tlat tlong blat blong).each do |field|
#places = #places.where(field => params[field])
end
end
end
I'm trying to build a simple search form in Ruby on Rails, my form is simple enough basically you select fields from a series of options and then all the events matching the fields are shown. The problem comes when I leave any field blank.
Here is the code responsible for filtering the parameters
Event.joins(:eventdates).joins(:categories).where
("eventdates.start_date = ? AND city = ? AND categories.name = ?",
params[:event][:date], params[:event][:city], params[:event][:category]).all
From what I get it's that it looks for events with any empty field, but since all of them have them not empty, it wont match unless all 3 are filled, another problem arises when I try to say, look events inside a range or array of dates, I'm clueless on how to pass multiple days into the search.
I'm pretty new to making search forms in general, so I don't even know if this is the best approach, also I'm trying to keep the searches without the need of a secialized model.
Below is probably what you are looking for. (Note: If all fields all blank, it shows all data in the events table linkable with eventdates and categories.)
events = Event.joins(:eventdates).joins(:categories)
if params[:event]
# includes below where condition to query only if params[:event][:date] has a value
events = events.where("eventdates.start_date = ?", params[:event][:date]) if params[:event][:date].present?
# includes below where condition to query only if params[:event][:city] has a value
events = events.where("city = ?", params[:event][:city]) if params[:event][:city].present?
# includes below where condition to query only if params[:event][:city] has a value
events = events.where("categories.name = ?", params[:event][:category]) if params[:event][:category].present?
end
To search using multiple days:
# params[:event][:dates] is expected to be array of dates.
# Below query gets converted into an 'IN' operation in SQL, something like "where eventdates.start_date IN ['date1', 'date2']"
events = events.where("eventdates.start_date = ?", params[:event][:dates]) if params[:event][:dates].present?
It will be more easy and optimised . If you use concern for filter data.
Make one concern in Model.
filterable.rb
module Filterable
extend ActiveSupport::Concern
module ClassMethods
def filter(filtering_params)
results = self.where(nil)
filtering_params.each do |key, value|
if column_type(key) == :date || column_type(key) ==
:datetime
results = results.where("DATE(#{column(key)}) = ?",
Date.strptime(value, "%m/%d/%Y")) if
value.present?
else
results = results.where("#{column(key)} Like ? ", "%#{value}%") if
value.present?
end
end
results
end
def resource_name
self.table_name
end
def column(key)
return key if key.split(".").count > 1
return "#{resource_name}.#{key}"
end
def column_type(key)
self.columns_hash[key].type
end
end
end
Include this concern in model file that you want to filter.
Model.rb
include Filterable
In your controller Add this methods
def search
#resources = Model.filter(class_search_params)
render 'index'
end
def class_search_params
params.slice(:id,:name) #Your field names
end
So, It is global solution. You dont need to use query for filter. just add this concern in your model file.
That's it.
I created a simple web form where users can enter some search criteria to look for venues e.g. a price range. When a user clicks "find" I use active record to query the database. This all works very well if all fields are filled in. Problems occur when one or more fields are left open and therefore have a value of null.
How can I work around this in my controller? Should I first check whether a value is null and create a query based on that? I can imagine I end up with many different queries and a lot of code. There must be a quicker way to achieve this?
Controller:
def search
#venues = Venue.where("price >= ? AND price <= ? AND romance = ? AND firstdate = ?", params[:minPrice], params[:maxPrice], params[:romance], params[:firstdate])
end
You may want to filter out all of the blank parameters that were sent with the request.
Here is a quick and DRY solution for filtering out blank values, triggers only one query of the database, and builds the where clause with Rails' ActiveRecord ORM.
This approach safeguards against SQL-injection, as pointed out by #DanBrooking. Rails 4.0+ provides "strong parameters." You should use the feature.
class VenuesController < ActiveRecord::Base
def search
# Pass a hash to your query
#venues = Venue.where(search_params)
end
private
def search_params
params.
# Optionally, whitelist your search parameters with permit
permit(:min_price, :max_price, :romance, :first_date).
# Delete any passed params that are nil or empty string
delete_if {|key, value| value.blank? }
end
end
I would recommend to make method in Venue
def self.find_by_price(min_price, max_price)
if min_price && max_price
where("price between ? and ?", min_price, max_price)
else
all
end
end
def self.find_by_romance(romance)
if romance
where("romance = ?", romance)
else
all
end
end
def self.find_by_firstdate(firstdate)
if firstdate
where("firstdate = ?", firstdate)
else
all
end
end
And use it in your controller
Venue
.find_by_price(params[:minPrice], params[:maxPrice])
.find_by_romance(params[:romance])
.find_by_firstdate(params[:firstdate])
Another solution to this problem, and I think a more elegant one, is using scopes with conditions.
You could do something like
class Venue < ActiveRecord::Base
scope :romance, ->(genre) { where("romance = ?", genre) if genre.present? }
end
You can then chain those, which would work as an AND if there is no argument present, then it is not part of the chain.
http://guides.rubyonrails.org/active_record_querying.html#scopes
Try below code, it will ignore parameters those are not present
conditions = []
conditions << "price >= '#{params[:minPrice]}'" if params[:minPrice].present?
conditions << "price <= '#{params[:maxPrice]}'" if params[:maxPrice].present?
conditions << "romance = '#{params[:romance]}'" if params[:romance].present?
conditions << "firstdate = '#{params[:firstdate]}'" if params[:firstdate].present?
#venues = Venue.where(conditions.join(" AND "))
I'm looking for a simple way to build up a filter query using given column/value hash. All of the values should be used in LIKE queries. I can build up the query and the parameters in arrays and pass it to where, like this:
def self.filter(filters=nil)
if filters.nil? || filters.empty?
return all
end
query = []
value_array = []
filters.each do |key, value|
query << "#{key} LIKE ?"
value_array << "%#{value}%"
end
where([query.join(' AND ')] + value_array)
end
But I was wondering if there is a better way of doing this either built into Rails (using version 4) or if there is a super simple gem that can easily accept a has and turn into a LIKE filter?
a nice way to play nice with hashes in queries is to make use of the Hash#slice method and scopes:
...
filtering_params(params).each do |key, value|
#products = #products.public_send(key, value) if value.present?
end
def filtering_params(params)
params.slice(:status, :location, :starts_with)
end
class Product < ActiveRecord::Base
scope :status, -> (status) { where status: status }
scope :location, -> (location_id) { where location_id: location_id }
scope :starts_with, -> (name) { where("name like ?", "#{name}%")}
end
Taken from here. After all you might need to restrict you logic to some specific queries in your DSL.
I am using rails to make a datatable that paginates with Ajax, and I am following railscast #340 to do so.
This episode makes use of a normal ActiveModel Class called ProductsDatatable or in my case OrdersDatatable to create and configure the table. My question has to do with ruby syntax in this class. I am trying to pass a collection of orders to the OrdersDatatable object, from the controller. I want to access this collection in the fetch_orders method.
I create the table object like this in order.rb:
#datatable = OrdersDatatable.new(view_context)
#datatable.shop_id = #current_shop.id
#datatable.orders_list = #orders # which is Order.in_process
And my OrdersDatatable class looks like this: (the important parts which probably need to change is the second line in initialize and the first line in fetch_orders)
class OrdersDatatable
include Rails.application.routes.url_helpers
include ActionView::Helpers::DateHelper
include ActionView::Helpers::TagHelper
delegate :params, :h, :link_to, :number_to_currency, to: :#view
attr_accessor :shop_id, :orders_list
def initialize(view)
#view = view
#orders_list = self.orders_list
end
def current_shop
Shop.find(shop_id)
end
def as_json(options = {})
{
sEcho: params[:sEcho].to_i,
iTotalRecords: orders.count,
iTotalDisplayRecords: orders.count,
aaData: data
}
end
private
def data
orders.map do |order|
[
order.id,
order.name,
h(time_tag(order.date_placed.in_time_zone)),
order.state,
order.source,
order.payment_status,
h(order.delivered? ? 'shipped' : 'unshipped'),
h(number_to_currency order.final_total, unit: order.currency.symbol),
h(link_to 'details', edit_admin_shop_order_path(current_shop, order)),
h(link_to 'delete', admin_shop_order_path(current_shop, order), method: :delete, data: { confirm: 'Are you sure?' } ),
]
end
end
def orders
#orders ||= fetch_orders
end
def fetch_orders
orders = orders_list.order("#{sort_column} #{sort_direction}")
orders = orders.page(page).per_page(per_page)
if params[:sSearch].present?
orders = orders.where("title like :search", search: "%#{params[:sSearch]}%")
end
orders
end
def page
params[:iDisplayStart].to_i/per_page + 1
end
def per_page
params[:iDisplayLength].to_i > 0 ? params[:iDisplayLength].to_i : 10
end
def sort_column
columns = %w[id name date_placed state source payment_status delivered final_total]
columns[params[:iSortCol_0].to_i]
end
def sort_direction
params[:sSortDir_0] == "desc" ? "desc" : "asc"
end
end
When I change the first line in fetch_orders to this
orders = Order.in_process.order("#{sort_column} #{sort_direction}")
which is the hard-coded equivalent, it does work. So I just need the correct syntax
Short answer: If you've got an array, and want to sort it, use the sort_by method:
orders = orders_list.sort_by{|order| "#{order.sort_column} #{order.sort_direction}"}
Long answer: The reason your original code doesn't work is that in this case
Order.in_process.order("#{sort_column} #{sort_direction}")
you are building a query. in_process is a named scope (passing in some conditions), and .order tells rails what to order the query by. Then, when it runs out of chained methods, the query executes (runs some sql) and gets the records out of the DB to build a collection of objects.
Once you are working with a collection of objects, you can't call the .order method on it, as that's just used to assemble an sql query. You need to use Array#sort_by instead. sort_by takes a code block, into which is passed each object in the collection (as order in my example but you could call it anything, it's just a variable name).
BTW, if you just want to call a method on all the objects to sort them, you can use a "shortcut syntax" like .sort_by(&:methodname). This uses a little trick of ruby called Symbol#to_proc (http://railscasts.com/episodes/6-shortcut-blocks-with-symbol-to-proc).
So, for example, if there was a method in Order like so
def sort_string
"#{self.sort_column} #{self.sort_direction}"
end
then you could change your code to
orders = orders_list.sort_by(&:sort_string)
which is neat.
If you have an array, then you can sort like this.
orders = orders_list.sort! {|a,b| a.sort_column <=> b.sort_direction}