How do I manually build form data? - ruby-on-rails-3

I have the following models:
Subject has_many Points
Point belongs_to Subject
Points are created using a form, and the controller is as follows
def create
#subject = Subject.find(params[:subject_id])
#point = #subject.points.build(params[:point])
if #point.save
flash[:success] = "You have created new data"
redirect_to subject_path(#point.subject_id)
else
render 'new'
end
end
At the moment a user can create Points for each Subject using a form. However, I want to also allow the user to upload mass points from a csv file. For this I am using the csv library (ruby 1.9.3)
After uploading the csv file, I put the csv file into a table as follows
thegrid = CSV.table(path, :headers => true, :header_converters => :symbol)
Where path is the path to the csv. The headers for the csv file match the column names in the database (including the subject_id column number)
I want to loop through the rows in the table and add each one to the database as follows
<% point = Hash.new %>
<% thegrid.each do |row| %>
<%
point = {
"name" => row[0],
"total_points" => row[1],
"subject_id" => row[2]
}
%>
<% #point = #subject.points.build(params[point]) %>
<% end %>
But the above doesn't appear to add the rows to the database. What is the correct way to do this loop, I think it may be the params that are causing a problem

I sorted this issue by updating the code as follows:
<%
params[:point] = {
name: row[0],
total_points: row[1],
subject_id: row[2]
}
%>
<% #point = #subject.points.build(params[:point]) %>

Related

Rails form - search engine

I try to create simple search engine but I meet some problmes. I have several search_field in my form and if either is empty should returns all objects. Otherwise when it has any content it should be selected by that content. Below is my sample form:
<%= form_for :product, url: products_path, method: :get do |form| %>
<%= form.search_field :brand %>
<%= form.search_field :model %>
<%= form.search_field :price_from %>
<%= form.search_field :price_to %>
<%= form.submit 'Submit' %>
<% end %>
my model method:
def self.search(search)
where(brand: search[:brand]).where(model: search[:model]).where("price >= ?", search[:price_from]).where("price <= ?", search[:price_to])
end
But the above piece of code is wrong because if I leave some field empty it is treated directly as empty string instead of ignore this field and final result is not correct.
Summary this form should work similarly to filter on online store
You'd could do something like this
def self.search(search)
results = all
results = results.where(brand: search[:brand]) if search[:brand]
results = results.where(model: search[:model]) if search[:model]
results = results.where("price >= ?", search[:price_from]) if search[:price_from]
results = results.where("price <= ?", search[:price_to]) if search[:price_to]
return results
end
Good luck.

Why isn't my search method working in Ruby on Rails?

In my Ruby on Rails application, I have a cinema system and am trying to return the screen a showing is in when a user searches for the showing.
To display the search drop down I am using this code in my _application.html.erb:
<%= render( :partial => '/screen_lookup', :locals => {:showings => #showings = Showing.all, :my_path => '/screens/display_screens_by_showing' })%>
Which renders the search from the _screen_lookup.html.erb:
<%= form_tag my_path, :method=>'post', :multipart => true do %>
<%= select_tag ('showings_id'),
options_from_collection_for_select(#showings, :id, :showing_times, 0 ),
:prompt => "Showings" %>
<%= submit_tag 'Search' %>
<% end %>
And uses the display_screens_by_showing in the screens_controller:
def display_screens_by_showing
#screens = Screen.showing_search(params[:showing_id])
if #screens.empty?
# assign a warning message to the flash hash to be displayed in
# the div "feedback-top"
flash.now[:alert] = "There are no films of that genre."
# return all products, in alphabetical order
#screens = Screen.all
end
render :action => "index"
end
And this searches using the method in the screen.rb model:
def self.showing_search(showing_id)
screen = Showing.where("id = ?", showing_id).screen_id
self.where("id = ?", screen)
end
Now, the problem I am having is that because a showing belongs_to a screen, and a screen has_many showings, I need to be able to search for the showing, and store that showing's screen_id in a variable to search for the screen that showing is in with, which I have tried doing in the model:
screen = Showing.where("id = ?", showing_id).screen_id
self.where("id = ?", screen)
But the error I am getting is:
NoMethodError in ScreensController#display_screens_by_showing
undefined method `screen_id' for #<ActiveRecord::Relation []>
These are the model relationships:
showing.rb:
class Showing < ActiveRecord::Base
belongs_to :screen
end
screen.rb:
class Screen < ActiveRecord::Base
has_many :showings
end
What code will get my search working?
The problem is that where doesn't return a record, it returns a relation that can be enumerated or chained, instead you want to use find or find_by to return a single record, which is kind equivalent to where + first
screen = Showing.find(showing_id).screen_id
which is sort of like doing
screen = Showing.where(id: showing_id).first.screen_id
If you want to pass a hash you can use find_by which will be like this
screen = Showing.find_by(id: showing_id).screen_id
PS:
I'm not sure what you're doing exactly, but i think those two lines can be merged into a single query ( not sure what it should be returning, but I'm assuming a screen )
def self.showing_search(showing_id)
Showing.find(showing_id).screen
end

Duplicating a record with associated images using Carrierwave

I have an app which you can store order/invoices in. I'm building a simple feature where you can duplicate invoices for my customers. I wrote this method in my Order.rb model which:
Takes the invoice, duplicates the associated lineitems, adds the new OrderID into them...and does the same for associated images.
def self.duplicate_it(invoice)
new_invoice = invoice.dup
new_invoice.save
invoice.lineitems.each do |l|
new_lineitem = l.dup
new_lineitem.order_id = new_invoice.id
new_lineitem.save
end
invoice.images.each do |i|
new_image = i.dup
new_image.order_id = new_invoice.id
new_image.save
end
return new_invoice
end
Unfortunately, you can't just .dup the image because there's all this associate expiration stuff since I'm storing images on S3. Is there a way to regenerate the image maybe using its image_url?
The error I get when running this is below. Which tells me not all the associated image information is dup'd correctly.
Showing /Users/bruceackerman/Dropbox/printavo/app/views/orders/_image-display.erb where line #3 raised:
undefined method `content_type' for nil:NilClass
Extracted source (around line #3):
1: <% #order.images.each do |image| %>
2: <% if image.image && image.image.file %>
3: <% if image.image.file.content_type == "application/pdf" %>
4: <%= link_to image_tag("/images/app/pdf.jpg",
5: :class => 'invoice-image'),
6: image.image_url,
i think you can do the following
invoice.images.each do |i|
new_image = new_invoice.images.new({ order_id: new_invoice.id })
new_image.image.download!(i.image_url)
new_image.store_image!
new_image.save!
end
This is actually how I did it for each lineitem on an order:
def self.duplicate_it(invoice)
new_invoice = invoice.dup :include => {:lineitems => :images} do |original, kopy|
kopy.image = original.image if kopy.is_a?(Image)
end
new_invoice.save!
return new_invoice
end
It is a bit late however this is my solution. I have had far too many problems with .download!
if #record.duplicable?
new_record = #record.dup
if new_record.save
#record.uploads.each do |upload|
new_image = new_record.uploads.new({ uploadable_id: new_record.id })
new_image.filename = Rails.root.join('public'+upload.filename_url).open
new_image.save!
end
end
Here is my upload.rb
class Upload < ActiveRecord::Base
belongs_to :uploadable, polymorphic: true
mount_uploader :filename, ImageUploader
end
Hope it helps!

rails OR query based on multiple checkbox selections

This seems like it should be a common problem but I'm having trouble finding an answer. Basically I want to have a form with 10 or so checkboxes which I'm creating with check_box_tag. When the form is submitted I want to generate a query that return all records that match ANY of the checked selections. So, the number of checked selections will vary.
So, for example, if I have
class Book < ActiveRecord::Base
belongs_to :author
end
I want to generate something like
Book.where("author_id = ? or author_id = ?", params[authors[0]], params[authors[1]]) if there are two boxes checked, etc.
Thanks for any insight.
Will this work for you?
Book.where(author_id: [array_of_author_ids])
You need to collect author_ids from params first
I recently had to do something similar, this is how I achieved this. It's pretty clever (at least I think so. :))
I created a query model that serializes the query column (text field) in JSON. I use a form to get the query data from the user with selection fields.
class BookQuery < ActiveRecord::Base
has_many :books
# loop through each foreign key of the Book table and create a hash with empty selection
def self.empty_query
q = {}
Book.column_names.each do |column_name|
next unless column_name.ends_with?("_id")
q.merge column_name => []
end
end
end
I'm using Author as an example below:
<%= form_for #book_query do |f| %>
<% for author in Author.all %>
<%= check_box_tag "book_query[query][author_ids][]", author.id, false%>
<%= author.name %>
<% end %>
<%= f.submit "Save Query" %>
<% end %>
When this form is submitted you ended up with parameters like this:
When the form is submitted it generates this parameter:
Parameters: {"utf8"=>"✓", "authenticity_token"=>"XXXXXXXXXXX", "book_query"=>{"query"=>{"author_ids"=>["2", "3"]}}, "commit"=>"Save Query"}
Now in the BookQuery controller's create action you can just do what create function always does:
def create
#book_query = BookQuery.build(params[:book_query])
if #book_query.save
flash[:success] = "Book query successfully saved."
redirect_to ...
else
flash[:error] = "Failed to save book query."
render :new
end
end
But by default rails serializes the data in hash type:
1.9.3p194 :015 > pp BookQuery.find(9).query
BookQuery Load (0.7ms) SELECT "book_queries".* FROM "book_queries" WHERE "book_queries"."id" = $1 LIMIT 1 [["id", 9]]
"--- !ruby/hash:ActiveSupport::HashWithIndifferentAccess\nauthor_ids:\n- '2'\n- '3'\n"
=> "--- !ruby/hash:ActiveSupport::HashWithIndifferentAccess\nauthor_ids:\n- '2'\n- '3'\n"
In BookQuery model, add the following:
serialize :query, JSON
But rail would change the IDs to string:
1.9.3p194 :018 > query = JSON.parse(BookQuery.find(10).query)
BookQuery Load (0.5ms) SELECT "book_queries".* FROM "book_queries" WHERE "book_queries"."id" = $1 LIMIT 1 [["id", 10]]
=> {"author_ids"=>["2", "3"]}
1.9.3p194 :019 > query["author_ids"]
=> ["2", "3"]
What I did then is override the attribute accessors in BookQuery model:
The below has to be done because the hash returns strings, not ids in integer.
def query=(query)
query.each_pair do |k, v|
if query[k].first.present?
query[k].map!(&:to_i)
else
query.except!(k)
end
end
write_attribute(:query, query)
end
# just want to avoid getting nil query's
def query
read_attribute(:query) || {}
end
To find book with this query, you can simply add this function to your Book model:
def self.find_by_book_query(book_query, options = {})
options[:conditions] = book_query.query
find(:all, options)
end
Now you get a customizable query string based on the model definition Book and everything works like the Rails way. :)

Rails HABTM fields_for – check if record with same name already exists

I have a HABTM-relation between the models "Snippets" and "Tags". Currently, when i save a snippet with a few tags, every tag is saved as a new record.
Now i want to check if a tag with the same name already exists and if that´s the case, i don´t want a new record, only an entry in snippets_tags to the existing record.
How can i do this?
snippet.rb:
class Snippet < ActiveRecord::Base
accepts_nested_attributes_for :tags, :allow_destroy => true, :reject_if => lambda { |a| a.values.all?(&:blank?) }
...
end
_snippet.html.erb:
<% f.fields_for :tags do |tag_form| %>
<span class="fields">
<%= tag_form.text_field :name, :class => 'tag' %>
<%= tag_form.hidden_field :_destroy %>
</span>
<% end %>
Ok, i´m impatient… after a while i found a solution that works for me. I don´t know if this is the best way, but i want to show it though.
I had to modify the solution of Ryan Bates Railscast "Auto-Complete Association", which handles a belongs_to-association to get it working with HABTM.
In my snippet-form is a new text field named tag_names, which expects a comma-separated list of tags.
Like Ryan, i use a virtual attribute to get and set the tags. I think the rest is self-explanatory, so here´s the code.
View "_snippet.html.erb"
<div class="float tags">
<%= f.label :tag_names, "Tags" %>
<%= f.text_field :tag_names %>
</div>
Model "snippet.rb":
def tag_names
# Get all related Tags as comma-separated list
tag_list = []
tags.each do |tag|
tag_list << tag.name
end
tag_list.join(', ')
end
def tag_names=(names)
# Delete tag-relations
self.tags.delete_all
# Split comma-separated list
names = names.split(', ')
# Run through each tag
names.each do |name|
tag = Tag.find_by_name(name)
if tag
# If the tag already exists, create only join-model
self.tags << tag
else
# New tag, save it and create join-model
tag = self.tags.new(:name => name)
if tag.save
self.tags << tag
end
end
end
end
This is just the basic code, not very well tested and in need of improvement, but it seemingly works and i´m happy to have a solution!