Rails 3.1, Ruby 1.9.3
So I have two models, both have two sets of coordinates.
The first model, Load, has from_lat/lng, as well as to_lat/lng.
The second model, Trucks, has current_lat/lng as well as destination_lat/lng.
What I'm trying to do is find all the results that have either the current_lat/lng or destination_lat/lng from the Truck model near the to_lat/lng of the Load model.
My model for lanes is something like:
class Load < ActiveRecord::Base
has_many :trucks
geocoded_by :custom_geocode
after_validation :custom_geocode
def custom_geocode
var = Geocoder.coordinates([from_city,from_state].compact.join(','))
var2 = Geocoder.coordinates([to_city,to_state].compact.join(','))
self.from_lat = var.first
self.from_lng = var.last
self.to_lat = var2.first
self.to_lng = var2.last
end
end
In my view, I have:
<% for truck in #trucks %>
<li><%= truck.destination_lat %></li>
<% end %>
Currently I am using this in my loads_controller:
def show
#load = Load.find(params[:id])
#trucks = Truck.near([#load.from_lat, #load.from_lng], 100, :order => "distance")
respond_to do |format|
format.html # show.html.erb
format.json { render json: #load }
end
end
The error I get is:
PG::Error: ERROR: column trucks.latitude does not exist
I know this is because the name of the columns are not the default :latitude and :longitude. How can I specify, during this specific search, which set of columns to use (destination_lat/lng or current_lat/lng) from the Truck model?
Related
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
I'm new to Rails, so it's possible I'm overlooking something simple. I have a Rails model called a story. Each story has_many segments, and each segment belongs_to a story. I use the same form to create both the story and its first segment by using a fields_for section of the form and setting the story model to accepts_nested_attributes_for :segments. I am currently able to use the form to create both a story and a segment simultaneously.
The problem is that each story also needs to store the id of its first segment, but when I'm saving the story, the segment hasn't yet been saved, so it doesn't yet have an id to store in the story, and I haven't been able to find a handle for the segment after the form is submitted so that I can save the segment first before the story is created. So my question is how do I save a record of the first_segment_id inside the story?
The following code may be relevant:
in app/models/story.rb
class Story < ActiveRecord::Base
attr_accessible :segments_attributes
has_many :segments
accepts_nested_attributes_for :segments
end
in app/models/segment.rb
class Segment < ActiveRecord::Base
attr_accessible :words
belongs_to :story
end
in app/views/stories/_ form.html.erb
<%= form_for(#story) do |f| %>
#...stories fields...
<%= f.fields_for :segments do |segment_form| %>
<div class="field">
<%= segment_form.label :words %><br />
<%= segment_form.text_area :words %>
</div>
<% end %>
<div class="actions">
<%= f.submit %>
</div>
<% end %>
in app/controllers/stories_ controller.rb
def new
#story = Story.new
#segment = #story.segments.build
# If I try replacing the above with #segment = #story.segments.create
# then I get the error message "You cannot call create unless the
# parent is saved," which is problematic because I need to find some way
# to get the id of #segment to save in the parent story, but the segment
# won't have an id until after it has been saved.
respond_to do |format|
format.html # new.html.erb
format.json { render json: #story }
end
end
def create
#story = Story.new(params[:story])
# #segment.save
# #story.first_segment_id = #segment.id
# If I uncomment the above two lines, I get the error message
# "undefined method `save' for nil:NilClass". It appears that
# #segment hasn't been passed from the "new" method above to
# this method as a handle of the first segment created, so I'm not
# able to save it to get an id for it before saving the story.
# Is there some way to save the segment here?
respond_to do |format|
#...if #story.save...
end
end
The params hash submitted by the form looks something like:
{ "story"=>{ Various_other_story_fields,
"segments_attributes"=>{"0"=>{"words"=>"dfsdsa"}}},
"commit"=>"Create Story"}
Is there a way to save the first segment's id in the story? I think perhaps I need to add a before_create inside my story model instead, but I'm not sure how do to this.
I would approach this differently, adding a numeric sort_order column to Segment so that you're not relying on Segment ids to determine what order they go in. Then you can define something like the following on your Story model rather than explicitly referencing the first segment in the database:
def first_segment
segments.order(:sort_order).first
end
If you're certain you need to store the first segment ID in the story, you can .save the story so that it knows its ID, saves its children, and knows their IDs. Something like:
def create
#story = Story.new(params[:story])
#story.save # Save the story and its child segment so that they both have IDs
#story.first_segment_id = #story.segments.first.id
#story.save
...
end
You should be able to do something like:
class Story < ActiveRecord::Base
attr_accessible :segments_attributes
has_many :segments
has_one :first_segment
accepts_nested_attributes_for :segments
end
def new
#story = Story.new
#segment = #story.segments.build
#story.first_segment = #segment
...
You'll have to add story_id to your segment table.
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!
I'm trying to retrieve data for all items from a box, a box can have compartments and I'd like to get all compartment info at the box level. items are made polymorphic as boxes won't necessarily have compartments.
MODEL
class Box < ActiveRecord::Base
has_many :compartments
has_many :items, :as => :itemable
end
In my Controller I can get results back with:
#box = Box.find(params[:id])
#itemable = #box.compartments.first
#itemable = #box.compartments.last
VIEW
<% #items.each do |item| %>
<%= item.name %>
<% end %>
but if I then try
#itemable = #box.compartments
OR
#itemable = #box.compartments.find(:all)
I get the error
undefined method `items' for #<ActiveRecord::Array>
OR
undefined method `items' for #<ActiveRecord::Relation>
Can anyone help with getting results back from all compartments?
So in compartments you have
belongs_to :box
has_many :items, :as => :itemable
Is this the case? #box.compartments should return an array of compartments right? It sounds like items is somehow getting called on #box.compartments somehow
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. :)