How to chain optional Mongoid criteria in separate statements? - ruby-on-rails

I'm trying to chain criteria based on optional rails
parameters.
I want to be able to simultaneously filter based on selected tags as
well as searching.
Here is the current code that works in all situations:
if params[:tag] and params[:search]
#notes = Note.tagged_with_criteria(params[:tag]).full_text_search(params[:search])
elsif params[:tag]
#notes = Note.tagged_with_criteria(params[:tag])
elsif params[:search]
#notes = Note.full_text_search(params[:search])
end
I tried simply using
#notes = Note.tagged_with_criteria(params[:tag]).full_text_search(params[:search])
without the if statement, but then if only one of the params was
given, then all notes are returned.
Each of the methods (tagged_with_criteria and full_text_search) are
returning Note.criteria if their parameter is nil / empty.
Is there a simpler, more elegant way to chain Mongoid criteria like this?
I'd rather keep tacking on criteria one-by-one instead of having to do
the weird "if params[...] and params[...]" thing..
UPDATE: here are the current methods:
def tagged_with_criteria(_tags)
_tags = [_tags] unless _tags.is_a? Array
if _tags.empty?
criteria
else
criteria.in(:tags => _tags)
end
end
def self.full_text_search(query)
if query
begin
regex = /#{query}/
# supplied string is valid regex (without the forward slashes) - use it as such
criteria.where(:content => regex)
rescue
# not a valid regexp -treat as literal search string
criteria.where(:content => (/#{Regexp.escape(query)}/))
end
else
# show all notes if there's no search parameter
criteria
end
end

In a situation like that, I would modify the scopes to do nothing when passed in blank values.
I think what might be happening is you are getting empty strings from the params hash, which is causing your code to think that something was entered. Try the scopes with these edits.
def tagged_with_criteria(_tags)
_tags = Array.wrap(_tags).reject(&:blank?)
if _tags.empty?
criteria
else
criteria.in(:tags => _tags)
end
end
def self.full_text_search(query)
if query.present?
begin
regex = /#{query}/
# supplied string is valid regex (without the forward slashes) - use it as such
criteria.where(:content => regex)
rescue
# not a valid regexp -treat as literal search string
criteria.where(:content => (/#{Regexp.escape(query)}/))
end
else
# show all notes if there's no search parameter
criteria
end
end

Related

Rails how to use where method for search or return all?

I am trying to do a search with multiple attributes for Address at my Rails API.
I want to search by state, city and/or street. But user doesn't need to send all attributes, he can search only by city if he wants.
So I need something like this: if the condition exists search by condition or return all results of this condition.
Example:
search request: street = 'some street', city = '', state = ''
How can I use rails where method to return all if some condition is nil?
I was trying something like this, but I know that ||:all doesn't work, it's just to illustrate what I have in mind.:
def get_address
address = Adress.where(
state: params[:state] || :all,
city: params[:city] || :all,
street: params[:street] || :all)
end
It's possible to do something like that? Or maybe there is a better way to do it?
This is a more elegant solution using some simple hash manipulation:
def filter_addesses(scope = Adress.all)
# slice takes only the keys we want
# compact removes nil values
filters = params.permit(:state, :city, :street).to_h.compact
scope = scope.where(filters) if filters.any?
scope
end
Once you're passing a column to where, there isn't an option that means "on second thought don't filter by this". Instead, you can construct the relation progressively:
def get_address
addresses = Address.all
addresses = addresses.where(state: params[:state]) if params[:state]
addresses = addresses.where(city: params[:city]) if params[:city]
addresses = addresses.where(street: params[:street]) if params[:street]
addresses
end
I highly recommend using the Searchlight gem. It solves precisely the problem you're describing. Instead of cluttering up your controllers, pass your search params to a Searchlight class. This will DRY up your code and keep your controllers skinny too. You'll not only solve your problem, but you'll have more maintainable code too. Win-win!
So in your case, you'd make an AddressSearch class:
class AddressSearch < Searchlight::Search
# This is the starting point for any chaining we do, and it's what
# will be returned if no search options are passed.
# In this case, it's an ActiveRecord model.
def base_query
Address.all # or `.scoped` for ActiveRecord 3
end
# A search method.
def search_state
query.where(state: options[:state])
end
# Another search method.
def search_city
query.where(city: options[:city])
end
# Another search method.
def search_street
query.where(street: options[:street])
end
end
Then in your controller you just need to search by passing in your search params into the class above:
AddressSearch.new(params).results
One nice thing about this gem is that any extraneous parameters will be scrubbed automatically by Searchlight. Only the State, City, and Street params will be used.

building a simple search form in Rails?

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.

Ignore parameters that are null in active record Rails 4

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 "))

Conditionally chaining where clauses in Rails ActiveRecord queries

I have a form that when filled has to trigger a particular query, depending on which parameters the form has, so I have a method in my model that I believe should look like this:
def form_query(params)
query = ''
if params.has_key?('size')
query = query.where(size: params['size'])
end
if params.has_key?('title')
query = query.where(title: params['title'])
end
# More conditionals depending on params.
end
My question is, what does query have to be at the beginning? I put query = '', but I am wondering what has to be the base case, so I can conditionally add more 'where' clauses.
Queries aren't strings; they're query objects. So you want something like
query = YourModel.scoped # Rails 3; in Rails 4, use .all
if params.has_key?('size')
query = query.where(size: params['size'])
end
etc.
Alternatively, you can update your code as below:
def self.form_query(params)
options = {}
fields = ["body", "title"].freeze ## Add other options
if params.present?
fields.each do |field|
options[field] = params[field] if params[field]
end
end
if options.present?
where(options)
else
all ## or nil if you don't want to show any records in view
end
end
Also, form_query should be a class method in your model.
Add more options in the fields array that you would like to query against.
It not only makes your code compact but also makes a single database call.
Here is a more condensed version of Kirti Thorat's version:
FIELDS = ["size", "title"].freeze ## Add other options
def self.form_query(params)
return all unless params.present?
options = params.select { |k, _v| FIELDS.include? k.to_s }
options.present? ? where(options) : all
end
I have done k.to_s so you can pass params keys as either strings or symbols.
If you want to return nil if no params are passed you can do this:
FIELDS = ["size", "title"].freeze ## Add other options
def self.form_query(params)
return unless params.present?
options = params.select { |k, _v| FIELDS.include? k.to_s }
where(options) if options.present?
end

Rails 3: Search method returns all models instead of specified

What I'm trying to do: I have a model "Recipe" in which I defined a method "search" that takes an array of strings from checkboxes (I call them tags), and a single string. The idea is to search the db for recipes that has anything in it's 'name' or 'instructions' that contains the string, AND also has any of the tags matching it's 'tags' property.
Problem: The search method return all the recipes in my db, and doesn't seem to work at all at finding by the specific parameters.
The action method in the controller:
def index
#recipes = Recipe.search(params[:search], params[:tag])
if !#recipes
#recipes = Recipe.all
end
respond_to do |format|
format.html
format.json { render json: #recipe }
end
end
The search method in my model:
def self.search(search, tags)
conditions = ""
search.present? do
# Condition 1: recipe.name OR instruction same as search?
conditions = "name LIKE ? OR instructions LIKE ?, '%#{search[0].strip}%', '%#{search[0].strip}%'"
# Condition 2: if tags included, any matching?
if !tags.empty?
tags.each do |tag|
conditions += "'AND tags LIKE ?', '%#{tag}%'"
end
end
end
# Hämtar och returnerar alla recipes där codition 1 och/eller 2 stämmer.
Recipe.find(:all, :conditions => [conditions]) unless conditions.length < 1
end
Any ideas why it return all records?
if you are using rails 3, then it is easy to chain find conditions
def self.search(string, tags)
klass = scoped
if string.present?
klass = klass.where('name LIKE ? OR instructions LIKE ?', "%#{string}%", "%#{string}%")
end
if tags.present?
tags.each do |tag|
klass = klass.where('tags LIKE ?', "%#{tag}%")
end
end
klass
end
When you do
search.present? do
...
end
The contents of that block are ignored - it's perfectly legal to pass a block to a function that doesn't expect one, however the block won't get called unless the functions decides to. As a result, none of your condition building code is executed. You probably meant
if search.present?
...
end
As jvnill points out, it is in general much nicer (and safer) to manipulate scopes than to build up SQL fragments by hand

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