I have a strange issue. That values from elements in my array disappear.
The Sinatra part looks like this:
config do
$api = MyWrappr.new
end
get "/"
erb :view, :locals => {:elements => $api.allElements }
end
So what allElements do is first check if there already is a array or not and then it check with the time if the array need to be refreshed.
def allElements
#elements ||= getElements
if Time.now-#time > 60
#elements = getElements
#time = Time.now
end
#elements
end
And #elements is an array with element this looks like this
class Element
attr_accessor :property_1 :property_2
end
Now when I start my application which use thin as server, and I refresh the site fast enough :property_2 just disappear and become nil. Why happen this and how can I fix that?
Oh and if I describe my problem to abstract here is the full project
Well, just the short story I'm a bit stupid.
I have manipulate the object in my view like this:
<div class="title">
<b><%= "#{element.property_1.slice!(0, 24)}" %><%= "..." if (element.property_1.length > 24) %></b>
</div>
And after that there is clear why property_1 is empty.
Related
I have a 1.6gb xml file, and when I parse it with Sax Machine it does not seem to be streaming or eating the file in chunks - rather it appears to be loading the whole file into memory (or maybe there is a memory leak somewhere?) because my ruby process climbs upwards of 2.5gb of ram. I don't know where it stops growing because I ran out of memory.
On a smaller file (50mb) it also appears to be loading the whole file. My task iterates over the records in the xml file and saves each record to a database. It takes about 30 seconds of "idling" and then all of a sudden the database queries start executing.
I thought SAX was supposed to allow you to work with large files like this without loading the whole thing in memory.
Is there something I am overlooking?
Many thanks
Update to add code sample
class FeedImporter
class FeedListing
include ::SAXMachine
element :id
element :title
element :description
element :url
def to_hash
{}.tap do |hash|
self.class.column_names.each do |key|
hash[key] = send(key)
end
end
end
end
class Feed
include ::SAXMachine
elements :listing, :as => :listings, :class => FeedListing
end
def perform
open('~/feeds/large_feed.xml') do |file|
# I think that SAXMachine is trying to load All of the listing elements into this one ruby object.
puts 'Parsing'
feed = Feed.parse(file)
# We are now iterating over each of the listing elements, but they have been "parsed" from the feed already.
puts 'Importing'
feed.listings.each do |listing|
Listing.import(listing.to_hash)
end
end
end
end
As you can see, I don't care about the <listings> element in the feed. I just want the attributes of each <listing> element.
The output looks like this:
Parsing
... wait forever
Importing (actually, I don't ever see this on the big file (1.6gb) because too much memory is used :(
Here's a Reader that will yield each listing's XML to a block, so you can process each Listing without loading the entire document into memory
reader = Nokogiri::XML::Reader(file)
while reader.read
if reader.node_type == Nokogiri::XML::Reader::TYPE_ELEMENT and reader.name == 'listing'
listing = FeedListing.parse(reader.outer_xml)
Listing.import(listing.to_hash)
end
end
If listing elements could be nested, and you wanted to parse the outermost listings as single documents, you could do this:
require 'rubygems'
require 'nokogiri'
# Monkey-patch Nokogiri to make this easier
class Nokogiri::XML::Reader
def element?
node_type == TYPE_ELEMENT
end
def end_element?
node_type == TYPE_END_ELEMENT
end
def opens?(name)
element? && self.name == name
end
def closes?(name)
(end_element? && self.name == name) ||
(self_closing? && opens?(name))
end
def skip_until_close
raise "node must be TYPE_ELEMENT" unless element?
name_to_close = self.name
if self_closing?
# DONE!
else
level = 1
while read
level += 1 if opens?(name_to_close)
level -= 1 if closes?(name_to_close)
return if level == 0
end
end
end
def each_outer_xml(name, &block)
while read
if opens?(name)
yield(outer_xml)
skip_until_close
end
end
end
end
once you have it monkey-patched, it's easy to deal with each listing individually:
open('~/feeds/large_feed.xml') do |file|
reader = Nokogiri::XML::Reader(file)
reader.each_outer_xml('listing') do |outer_xml|
listing = FeedListing.parse(outer_xml)
Listing.import(listing.to_hash)
end
end
Unfortunately there are now three different repos for sax-machine. And worse, the gemspec version was not bumped.
Despite the comment on Greg Weber's blog, I don't think this code was integrated into pauldix's or ezkl's forks. To use the lazy, fiber-based version of the code, I think you need to specifically reference gregweb's version in your gemfile like this:
gem 'sax-machine', :git => 'https://github.com/gregwebs/sax-machine'
I forked sax-machine so that it uses constant memory: https://github.com/gregwebs/sax-machine
Good news: there is a new maintainer that is planning on merging my changes.
Myself and the new maintainer have been using my fork without issue for a year now.
You are right, SAXMachine reads the whole document eagerly. Have a look at it's handler sources: https://github.com/pauldix/sax-machine/blob/master/lib/sax-machine/sax_handler.rb
To solve your Problem, I would use http://nokogiri.rubyforge.org/nokogiri/Nokogiri/XML/SAX/Parser.html directly and implement the handler yourself.
I hope I am asking this right, so please let me know if I'm way off.
The problem is trying to build a homepage that draws from multiple controllers, to display the nearest locations from multiple controllers, ie. food, businesses, ect.
Right now the individual listings pages have maps drawn from their respective
#json = Controller.all.to_gmaps4rails
How would I do something like :
#json = Controller1 Controller2 .all.to_gmaps4rails
I hope this isnt a noob question and I'm just having a bad day. Thanks guys!
edit 12.5.2011 #seanhill - this is one of the models, the other sections are very close to this format. First off, I wasn't even sure if my homepage requires it's own model, as it doesn't interact with the db at all, more pulling data from controllers that do the work. Thanks for the response Sean!
class Dining < ActiveRecord::Base
validates_uniqueness_of :name, :message => "already exists"
attr_accessible :name, :address, :cuisine, :latitude, :longitude, :about, :facebook, :twitter, :phone, :website
geocoded_by :address
after_validation :geocode, :if => :address_changed?
acts_as_gmappable :process_geocoding => false
def gmaps4rails_address
"#{self.address}"
end
def gmaps4rails_infowindow
"<h3>#{self.name}</h3><br /><h5>#{self.cuisine}</h5>"
end
def self.search(search)
if search
where('name LIKE ?', "%#{search}%")
else
scoped
end
end
end
Try this
holder = Controller1.all
holder << Controller2.all
#json = holder.flatten.map{|h| {lng: h.longitude, lat: h.latitude, class: h.class.to_s}}.to_json
Make sure to change longitude and latitude based on your column names and use js to manipulate the markers based upon class.
As the #Sean Hill said you shouldn't be calling .all on controllers but I think you have a slight misunderstanding of how things are working. Assuming you have a Model called Dining and another called Shop, when you call Dining.all or Shop.all inside class DiningsController < ApplicationController, you are calling .all on either the Dining Model or the Shop Model not on the DiningsController.
The information you display through a controller is only limited by the methods you call in it although it is best practice ensure the main focus of the information displayed is related to the respective controller.
So what you are really trying to do is get the records from multiple models and group them together to display them in a single map.
With that said the answer should read something like this
holder = Dining.all # Takes all Dining records returned as an array and sets them to holder variable
holder << Shop.all # Pushes the Shop records array into the holder with the dining records
holder.flatten!# Next we flatten the array so we only have a single array.
# Then we use the map method to run the given code one time for each instance
# in the holder array to extract the info we need. The results for every instance
# in holder are returned in an array which we then convert to_json.
#json = holder.map{|h| {lng: h.longitude, lat: h.latitude, class: h.class.to_s}}.to_json
#json1 = something.to_gmaps4rails
#json2 = something.to_gmaps4rails
#json = (JSON.parse(#json1) + JSON.parse(#json2)).to_json
I populated the map with my initial data of festivals, and then added the rides to it with javascript with this code,
<% content_for :scripts do %>
<script type="text/javascript">
Gmaps.map.callback = function() {
$.getJSON('/rides_gmap', function(data){
Gmaps.map.addMarkers(data);
});
}
</script>
<%end%>
In the rides controller I had this
def rides_gmap
#rides = Ride.all
#json = #rides.to_gmaps4rails do |ride, marker|
marker.infowindow render_to_string(:partial => "/rides/infowindow", :locals => { :ride => ride})
marker.picture({
'picture' => view_context.image_path("orange-dot.png"),
'width' => 20,
'height' => 20
})
marker.title "#{ride.address}"
marker.json({:ride_id => ride.id, :ride_festivaltype => ride.festival.festivaltype
end
respond_with #json
end
I hope this helps.
Say I have this:
class Account
...
property :charge, Decimal, :precision => 7, :scale => 2
...
classy stuff
...
def self.balance(prefix)
x = Account.get(prefix.to_sym).order(:fields => [:charge]).sum(:charge)
sprintf("%5.2f", x)
end
end
(Edit: The value of all :charge fields is 0.13E2 (0.1E2 + 0.3E1). This is correctly returned. Only in a View does it seem to get borked from sprintf)
In IRB Account.balance(:AAA) returns => "13.00"
if I call Account.balance(:AAA) from a view I get TypeError at /accounts
can't convert nil into Float
Account.balance(:AAA) works anywhere I call it except in a view. If I remove sprintf("%5.2f", x) I get 0.13E2 in my view. (using Account.balance(:AAA).to_f in a view gives me 13.0)
Is sinatra incompatible with sprintf? or am I not understanding how to use sprintf?
(Edit: This is the offending view:)
<section>
<% #accounts.each do |account| %>
<article>
<h2><%= account.prefix %></h2>
<span><p>This account belongs to <%= account.name %> & has a balance of $<%= Account.balance(account.prefix) %>.</p></span>
</article>
<% end %>
</section>
Wouldn't it make more sense to define balance as an instance method rather than a class method? It looks from your example like you're calling balance in an account-specific way anyway, so why not make it:
# the model
class Account
#...
def balance
amount = self.order(:fields => [:charge]).sum(:charge)
sprintf "%5.2f", amount
# or the infix version:
"%5.2f" % amount
end
end
,
# the view
...balance of $<%= account.balance %>...
I know that this doesn't address sprintf per se, but the problem is more likely to be coming from the slightly convoluted lookup than from a built-in method. Even if my specific code doesn't suit your application, it might be worth simplifying the lookup step, even if that involves a few more lines of code.
The advantage of this approach is that there is no doubt that you'll be getting the right Account record.
tested it with a little sinatra app and it worked for me
app.rb
#!/usr/bin/env ruby
require 'rubygems'
require 'sinatra'
get '/' do
#x = 10.23
erb :index
end
views/index.erb
<%= sprintf("%5.2f", #x) %>
output:
10.23
ruby 1.9.2 / sinatra 1.3.1
I think there is another error before the sprintf because of your error message:
can't convert nil into Float
seems like your x is nil. try to be sure that x is not nil there, then sprintf should work as expected.
I have an array #cities = ["Vienna", "Barcelona", "Paris"];
and I am trying to display the individual items with a spacer in between. However it is possible that there is only 1 element in the array, in which case I do not want to display the spacer. And also the array could be empty, in which case I want to display nothing.
For the above array I want the following output:
Vienna
-----
Barcelona
-----
Paris
I use an erb template cityview to apply formatting, css, etc before actually printing the city names. Simplified, it looks like this:
<p><%= #cities[#city_id] %></p>
I have implemented it as follows...
unless #array.empty?
#city_id = 0;
erb :cityview
end
unless #array[1..-1].nil?
#array[1..-1].each_index do |i|
#city_id = i+1;
puts "<p>-------</p>";
erb :cityview
end
end
Is there a better way?
#cities.join("<p>--------</p>")
Edit to address the template
Here I'm assuming that there's an erbs method that returns the rendered template without doing a puts. Returning the string allows easier manipulation and reuse.
#cities.map { |c| #city = c; erb :cityview }.join("<p>--------</p>")
I'd prefer:
erb:
<p><%= #city %></p>
and loop
#array.each_with_index do |e, i|
#city = e
erb :cityview
puts "<p>-------</p>" if i < #array.length - 1
end
I assume you have split the erb, bit because you want to customize it.
If you want to mix HTML with your city names then you'll need to worry about HTML encoding things before you mix in your HTML. Using just the standard library:
require 'cgi'
html = #cities.map { |c| CGI.escapeHTML(c) }.join('<p>-----</p>')
If you're in Rails, then you can use html_escape from ERB::Util and mark the result as safe-for-HTML with html_safe to avoid having to worry about the encoding in your view:
include ERB::Util
html = #cities.map { |c| html_escape(c) }.join('<p>-----</p>').html_safe
The simpler solution would be to use a spacer template.
http://guides.rubyonrails.org/layouts_and_rendering.html#spacer-templates
I have an array of strings, called #theModels, in a routine implemented as part of a Sinatra server. These models are options for the user to select, and are obtained by the back end (the idea being, as new models are added, then the front end code should not change).
I'm using haml to render html.
How can I enumerate each element in the list of #theModels such that each element is a checkbox? And how can I obtain which checkboxes the user has selected?
I see that just putting
= #theModels
will give me the list of strings contained in #theModels, but without spacing or the like, and certainly not in checkboxes. I've found this question that appears to be similar, but my haml-fu isn't good enough to convert that into what I need.
UPDATE:
These are options associated with a file upload, such that now the code looks like:
%form{:action=>"/Upload",:method=>"post",:enctype=>"multipart/form-data"}
- #theModelHash.each do |key,value|
%br
%input{:type=>"checkbox", :name=>"#{key}", :value=>1, :checked=>value}
=key
%input{:type=>"file",:name=>"file"}
%input{:type=>"submit",:value=>"Upload"}
Problem is, that puts a file upload button on each option, instead of at the end. I only want one submit button in the end; should I have two forms that both report their results when the 'Upload' button is pressed?
UPDATE2:
After a moment's thought, the above can be modified to:
Thanks!
%form{:action=>"/Upload",:method=>"post",:enctype=>"multipart/form-data"}
- #theModelHash.each do |key,value|
%br
%input{:type=>"checkbox", :name=>"#{key}", :value=>1, :checked=>value}
=key
%form{:action=>"/Upload",:method=>"post",:enctype=>"multipart/form-data"}
%input{:type=>"file",:name=>"file"}
%input{:type=>"submit",:value=>"Upload"}
And that appears to do what I want.
I think you should send the content as an hash instead.
This will give you the opportunity to set initial values in the form.
The hash #params will give you the result.
E.g. {"oranges"=>"1"}
#app.haml
%form{:method => 'post', :action => "/"}
- #models.each do |key,value|
%br
%input{:type=>"checkbox", :name=>"#{key}", :value=>1, :checked=>value}
=key
%input{:type => :submit, :value => "Save"}
#app.rb
require 'sinatra'
require 'haml'
get '/' do
#models = {"oranges" => true, "bananas" => false}
haml :app
end
post '/' do
#params.inspect
end
The link you provided linked to a rails solution where you have a function returning the proper html.
You can define this function yourself:
Input: key, value
Output: %input{:type=>"checkbox", :name=>"#{key}", :value=>1, :checked=>value}
def check_box(key, value)
...
end
and call it in haml with
=check_box(key,value)