Videos matching: Ruby

do you have some basic tutorial for beginner to deploy rails. I am trying to deploy my rails application using capistrano. I use More

do you have some basic tutorial for beginner to deploy rails. I am trying to deploy my rails application using capistrano. I use https://github.com/capistrano/capistrano/wiki/2.x-From-The-Beginning this material but still, it have become hard for me to get concept. Will please suggest me some best one.

Looking to set up a class method that can return an array of instances. I'm running into some trouble about the point where I try to modify the inst...More

Looking to set up a class method that can return an array of instances. I'm running into some trouble about the point where I try to modify the instances' variables NoMethodError: undefined method 'name=' for #<Class:0x007fe65c8560c0>.

class User
  attr_accessor :name

  def self.sample_users
    megan = self.class.new
    megan.name = "Megan"

    jack = self.class.new
    jack.name = "Jack"

    [megan, jack]
  end
end

I feel like this should be possible in Ruby. Any guidance?

How can I see the latest available version of a gem using the Linux command line interface?

Using gem, the closest I can get is gem li...More

I have a class and a spec.

class Store
  def activate(product_klass, product_id)
    product = product_klass.find(product_id)
    if...More

I solved my problem through

require_relative
require './whateverfileiplannedtorequire'
load 'whateverfileiplannedtorequire'
<...More

I solved my problem through

require_relative
require './whateverfileiplannedtorequire'
load 'whateverfileiplannedtorequire'

but I am trying to get require to work without the ./ at the beginning as is advertised in the Beginning Ruby book. I hoped pushing my CWD into the $: array would fix this, but it didn't. How would I manage to get require to work as shown in the book?

I know that ruby has many methods, especially on array or array like objects, for example sort or flatten. However, these ...More

I know that ruby has many methods, especially on array or array like objects, for example sort or flatten. However, these methods also have a twin (the one with an exclamation mark) like sort! and flatten!.

Now my questions are:

• What is the difference between flatten and flatten! (destructive flatten)?
• A more general question, why is it called destructive?

Thanks in advance!

Anyone have any idea what might be happening in this situation? Why is using self.class or scope resolution ::MyModel nece...More

Anyone have any idea what might be happening in this situation? Why is using self.class or scope resolution ::MyModel necessary?

class MyModel < ActiveRecord::Base

  belongs_to :other_model
  validate :custom_validation

  private
  def custom_validation
    if MyModel.where(some_field: 1).count > 0
      errors.add(:some_field, "foo")
    end
  end
end

# ... In some other part of the code base

my_model_instance = @other_model.my_models.find_or_initialize_by_some_field("foo")
my_model_instance.save
# Raises error - MyModel::MyModel is undefined

The above code works fine most of the time. But for some reason, in one situation it was throwing that exception. Changing the custom_validation function to use self.class instead of MyModel and it works.

  def custom_validation
    if self.class.where(some_field: "bar").count > 0
      errors.add(:some_field, "error message")
    end
  end

Has anyone seen anything like this before? Why/how can the constant MyModel be interpreted as MyModel::MyModel is this specific situation?

Ruby 2.0.0-p195 and Rails 3.2.13

edited: Clarify/add question about why scope resolution becomes necessary.

This question is pretty similar but it is still unclear to me why using MyModel without scope resolution works fine most of the time.

I was reading up on Finagle and Akka, and was wondering if there are any similar frameworks in the ruby world?

Anyone have any idea what might be happening in this situation? Why is using self.class or scope resolution ::MyModel necessary?

class MyModel < ActiveRecord::Base

  belongs_to :other_model
  validate :custom_validation

  private
  def custom_validation
    if MyModel.where(some_field: 1).count > 0
      errors.add(:some_field, "foo")
    end
  end
end

# ... In some other part of the code base

my_model_instance = @other_model.my_models.find_or_initialize_by_some_field("foo")
my_model_instance.save
# Raises error - MyModel::MyModel is undefined

The above code works fine most of the time. But for some reason, in one situation it was throwing that exception. Changing the custom_validation function to use self.class instead of MyModel and it works.

  def custom_validation
    if self.class.where(some_field: "bar").count > 0
      errors.add(:some_field, "error message")
    end
  end

Has anyone seen anything like this before? Why/how can the constant MyModel be interpreted as MyModel::MyModel is this specific situation?

Ruby 2.0.0-p195 and Rails 3.2.13

edited: Clarify/add question about why scope resolution becomes necessary.

This question is pretty similar but it is still unclear to me why using MyModel without scope resolution works fine most of the time.

I am trying to grab large numbers from a file, store them as an array, and add them up.

nums = Array.new
x, total=0, 0
file = File.o...More

I needed to add a variable into a Hash. I was trying to do this:

actorsChickens = Hash.new
nicolasCage = gets.chomp # is a string
ch...More

i'm writing a client to a third-party API, and they provide data in a weird format. At first, it might look like JSON but it's not, and i'm a bit co...More

i'm writing a client to a third-party API, and they provide data in a weird format. At first, it might look like JSON but it's not, and i'm a bit confused about how i should handle that.

It's a key-value based format (Much like JSON).

• Keys are separated by '=' from their values.
• Keys and values are wrapped within double-quotes.
• Dictionaries start with '{' and end with '}'.
• Arrays start with '(' and end with ')'
• Lines end with ';' (Excepted for arrays content) and end-of-line character (\r i think).
• Sometimes, there seem to be unicode (Stuff like \U2623 for the BioHazard sign) in strings.

What could possibly be this format? Shall i use a premade gem to parse it, or should i build my own parser?

{ "anArray" = (
  "100",
  "200",
  "300"
  );
  "aDictionary" = {
    "aString" = "Something";
  };
}

EDIT This format seems to be Apple's property list, but it's not XML neither Binary... This make sense as the API is from a WebObjects webservice. i will try to use CFPropertyList gem to parse it, if there is a better solution, please let me know.

I need to pass to an application which uses REST API parameters in following XML file

paramValue = "string"
xmlIn2 = '
 <?xml ver...More

I have a text field where it accepts only the text that satisfies the below criteria:

Text format of the below type where 'A' can be any ran...More

I have a text field where it accepts only the text that satisfies the below criteria:

Text format of the below type where 'A' can be any random alphabets, 'D' is any numerical digit, but last digit is sum of all other digits modulo 10.

AAD-AAA-DDD

for example:

KN3-MNO-41_, this means the last digit is: 3 + 4 + 1 = 8, so it becomes: KN3-MNO-418
HK5-SFO-32_, this means the last digit is: 5 + 3 + 2 = 10, so it becomes HK5-SFO-320

I am in my intial learning of ruby, please help me: so how do I include these checks in the script and validate that the input text meets the criteria.

Thanks

I don't have any ruby installed on my linux mint by apt-get. Instead, I installed ruby using More

I don't have any ruby installed on my linux mint by apt-get. Instead, I installed ruby using ruby-build. I now have ruby installation in

/opt/rubies/ruby-2.0.0-p0/

How do I make this ruby installation the 'system' ruby just like apt-get sets ruby executable during apt-get install ruby1.9.1 for example.

I want to register this version as system ruby and when I use rubies switching with chruby (or rvm or rbenv) I want that to be seen as system ruby?

Do I simply use update-alternatives? Do I reinstall ruby from source with make? Any other suggestions please.

This is the HTML I'm working with:

<div class="pbSubsection">
    <table class="detailList" cellspacing="0" cellpadding="0"...More

I have this array:

arr = [["a","b","c"],[2,3,5],[3,6,8],[1,3,1]]

which is representing a prawn-table containing co...More

I have this array:

arr = [["a","b","c"],[2,3,5],[3,6,8],[1,3,1]]

which is representing a prawn-table containing columns "a", "b", and "c".

How do I remove the entire column "c" with all its values, 5, 8, 1?

Maybe there are useful hints in "Create two-dimensional arrays and access sub-arrays in Ruby" and "difficulty modifying two dimensional ruby array" but I can't transfer them to my problem.

I have been trying to install the watir gem for ruby 2. I followed the watir books install instructions exactly but once the watir install get to th...More

I have been trying to install the watir gem for ruby 2. I followed the watir books install instructions exactly but once the watir install get to the mini_magick gem it gives this error

ERROR: While executing gem ... (Errno::EINVAL) Invalid argument - C:/Ruby200/lib/ruby/gems/2.0.0/gems/mini_magick-3.6.0/tes t/files/special! "chars'.gif

Anyone know how to get around this? I noticed that nokogiri was acting kind of weird being unable to convert from ASCII to ITF-8. Maybe this has something to do with it. Thanks y'all

I'm using RSpec to test some engine models.

My preference would be to test the parts that are independent from the (dummy) app outside of th...More

I'm using RSpec to test some engine models.

My preference would be to test the parts that are independent from the (dummy) app outside of the app. I'd prefer to have non-app tests live at the top level and not be hidden in spec/dummy/spec.

The problem is that by default (AFAICT) engine initializers aren't run if the engine isn't mounted.

Should I just go with what appears to be expected, i.e., put all my specs in the dummy app and run RSpec from the dummy app's directory, even when the tests aren't related to the app as a whole?

Or should I run initializers from a top-level spec helper for the non-app specs? Or some other way?

If I do, are there dummy app repercussions?

In the past, I have successfully used Nokogiri to scrape websites using a simple Ruby script. For a...More

In the past, I have successfully used Nokogiri to scrape websites using a simple Ruby script. For a current project, I need to scrape a website that only uses inline CSS. As you can imagine, it is an old website.

What possibilities do I have to target specific elements on the page based on the inline CSS of the elements? It seems this is not possible with Nokogiri or have I overlooked something?

UPDATE: An example can be found here. I basically need the main content without the footnotes. The latter have a smaller font size and are grouped below each section.

I am using ruby 1.9.2 and I am getting following error while running rake db:migrate command

found unknown escape character while parsing a ...More

I am using ruby 1.9.2 and I am getting following error while running rake db:migrate command

found unknown escape character while parsing a quoted scalar at line ...

Anybody have any idea why this error is coming ?

I'd like to count the number of times a set of words appear in each paragraph in a text file. I am able to count the number of times a set of words ...More

I'd like to count the number of times a set of words appear in each paragraph in a text file. I am able to count the number of times a set of words appears in an entire text.

It has been suggested to me that my code is really buggy, so I'll just ask what I would like to do, and if you want, you can look at the code I have at the bottom.

So, given that "frequency_count.txt" has the words "apple pear grape melon kiwi" in it, I want to know how often "apple" shows up in each paragraph of a separate file "test_essay.txt", how often pear shows up, etc., and then for these numbers to be printed out in a series of lines of numbers, each corresponding to a paragraph.

For instance:

apple, pear, grape, melon, kiwi
3,5,2,7,8
2,3,1,6,7
5,6,8,2,3

Where each line corresponds to one of the paragraphs.

I am very, very new to Ruby, so thank you for your patience.

output_file = '/Users/yirenlu/Quora-Personal-Analytics/weka_input6.csv'
o = File.open(output_file, "r+")

common_words = '/Users/yirenlu/Quora-Personal-Analytics/frequency_count.txt'
c = File.open(common_words, "r")

c.each_line{|$line1|
    words1 = $line1.split
    words1.each{|w1|
        the_file = '/Users/yirenlu/Quora-Personal-Analytics/test_essay.txt'
        f = File.open(the_file, "r")
        rows = File.readlines("/Users/yirenlu/Quora-Personal-Analytics/test_essay.txt")
        text = rows.join
        paragraph = text.split(/\n\n/)
        paragraph.each{|p|
            h = Hash.new
            puts "this is each paragraph"
            p.each_line{|line|
                puts "this is each line"
                words = line.split
                words.each{|w|
                    if w1 == w
                        if h.has_key?(w)
                            h[w1] = h[w1] + 1
                        else
                            h[w1] = 1
                        end
                        $x = h[w1]
                    end
                }
            }
            o.print "#{$x},"
        }
    }
    o.print "\n"
    o.print "#{$line1}"
}

I am trying to parse a CSV file generated from an Excel spreadsheet.

Here is my code

require 'csv'
file = File.open("input_f...More

I'm taking my first tentative steps with Ruby on Rails. I'm trying to get it up and running on a Windows machine (Win7 64). I installed using RubyIn...More

I'm taking my first tentative steps with Ruby on Rails. I'm trying to get it up and running on a Windows machine (Win7 64). I installed using RubyInstaller and then installed Rails using Gem.

I've had a bit of a nightmare because of missing gems, having to install devkit etc. which has been great fun for someone who has no idea what they're doing.

Anyway, I've finally got to a point where I can run a new "empty" rails project and I was hoping to see the default rails page.

Unfortunately instead I get an Internal Server Error and the following in the log:

[2011-11-16 10:30:56] INFO  WEBrick 1.3.1
[2011-11-16 10:30:56] INFO  ruby 1.9.3 (2011-10-30) [i386-mingw32]
[2011-11-16 10:30:56] INFO  WEBrick::HTTPServer#start: pid=3432 port=3000
[2011-11-16 10:31:19] ERROR ArgumentError: dump format error for symbol(0x6)
    C:/Ruby193/lib/ruby/gems/1.9.1/gems/actionpack-3.1.2.rc2/lib/action_view/template.rb:24:in `load'
    C:/Ruby193/lib/ruby/gems/1.9.1/gems/actionpack-3.1.2.rc2/lib/action_view/template.rb:24:in `<top (required)>'
    C:/Ruby193/lib/ruby/gems/1.9.1/gems/coffee-rails-3.1.1/lib/coffee/rails/template_handler.rb:17:in `block in <top (required)>'
    C:/Ruby193/lib/ruby/gems/1.9.1/gems/activesupport-3.1.2.rc2/lib/active_support/lazy_load_hooks.rb:36:in `instance_eval'
    C:/Ruby193/lib/ruby/gems/1.9.1/gems/activesupport-3.1.2.rc2/lib/active_support/lazy_load_hooks.rb:36:in `execute_hook'
    C:/Ruby193/lib/ruby/gems/1.9.1/gems/activesupport-3.1.2.rc2/lib/active_support/lazy_load_hooks.rb:43:in `block in run_load_hooks'
    C:/Ruby193/lib/ruby/gems/1.9.1/gems/activesupport-3.1.2.rc2/lib/active_support/lazy_load_hooks.rb:42:in `each'
    C:/Ruby193/lib/ruby/gems/1.9.1/gems/activesupport-3.1.2.rc2/lib/active_support/lazy_load_hooks.rb:42:in `run_load_hooks'
    C:/Ruby193/lib/ruby/gems/1.9.1/gems/actionpack-3.1.2.rc2/lib/action_view/base.rb:216:in `<class:Base>'
    C:/Ruby193/lib/ruby/gems/1.9.1/gems/actionpack-3.1.2.rc2/lib/action_view/base.rb:133:in `<module:ActionView>'
    C:/Ruby193/lib/ruby/gems/1.9.1/gems/actionpack-3.1.2.rc2/lib/action_view/base.rb:8:in `<top (required)>'
    C:/Ruby193/lib/ruby/gems/1.9.1/gems/actionpack-3.1.2.rc2/lib/abstract_controller/view_paths.rb:90:in `view_paths='
    C:/Ruby193/lib/ruby/gems/1.9.1/gems/actionpack-3.1.2.rc2/lib/abstract_controller/view_paths.rb:76:in `prepend_view_path'
    C:/Ruby193/lib/ruby/gems/1.9.1/gems/railties-3.1.2.rc2/lib/rails/engine.rb:532:in `block (2 levels) in <class:Engine>'
    C:/Ruby193/lib/ruby/gems/1.9.1/gems/activesupport-3.1.2.rc2/lib/active_support/lazy_load_hooks.rb:36:in `instance_eval'
    C:/Ruby193/lib/ruby/gems/1.9.1/gems/activesupport-3.1.2.rc2/lib/active_support/lazy_load_hooks.rb:36:in `execute_hook'
    C:/Ruby193/lib/ruby/gems/1.9.1/gems/activesupport-3.1.2.rc2/lib/active_support/lazy_load_hooks.rb:43:in `block in run_load_hooks'
    C:/Ruby193/lib/ruby/gems/1.9.1/gems/activesupport-3.1.2.rc2/lib/active_support/lazy_load_hooks.rb:42:in `each'
    C:/Ruby193/lib/ruby/gems/1.9.1/gems/activesupport-3.1.2.rc2/lib/active_support/lazy_load_hooks.rb:42:in `run_load_hooks'
    C:/Ruby193/lib/ruby/gems/1.9.1/gems/actionpack-3.1.2.rc2/lib/action_controller/base.rb:234:in `<class:Base>'
    C:/Ruby193/lib/ruby/gems/1.9.1/gems/actionpack-3.1.2.rc2/lib/action_controller/base.rb:171:in `<module:ActionController>'
    C:/Ruby193/lib/ruby/gems/1.9.1/gems/actionpack-3.1.2.rc2/lib/action_controller/base.rb:3:in `<top (required)>'
    C:/Ruby193/lib/ruby/gems/1.9.1/gems/actionpack-3.1.2.rc2/lib/action_dispatch/middleware/static.rb:31:in `ext'
    C:/Ruby193/lib/ruby/gems/1.9.1/gems/actionpack-3.1.2.rc2/lib/action_dispatch/middleware/static.rb:15:in `match?'
    C:/Ruby193/lib/ruby/gems/1.9.1/gems/actionpack-3.1.2.rc2/lib/action_dispatch/middleware/static.rb:47:in `call'
    C:/Ruby193/lib/ruby/gems/1.9.1/gems/railties-3.1.2.rc2/lib/rails/engine.rb:456:in `call'
    C:/Ruby193/lib/ruby/gems/1.9.1/gems/rack-1.3.5/lib/rack/content_length.rb:14:in `call'
    C:/Ruby193/lib/ruby/gems/1.9.1/gems/railties-3.1.2.rc2/lib/rails/rack/log_tailer.rb:14:in `call'
    C:/Ruby193/lib/ruby/gems/1.9.1/gems/rack-1.3.5/lib/rack/handler/webrick.rb:59:in `service'
    C:/Ruby193/lib/ruby/1.9.1/webrick/httpserver.rb:138:in `service'
    C:/Ruby193/lib/ruby/1.9.1/webrick/httpserver.rb:94:in `run'
    C:/Ruby193/lib/ruby/1.9.1/webrick/server.rb:191:in `block in start_thread'

The line throwing the error is "conversions = Marshal.load(File.read(filename))" in the following code block:

if defined?(RUBY_ENGINE) && RUBY_ENGINE == 'ruby' && RUBY_VERSION == '1.9.3' && RUBY_PATCHLEVEL == 0
  # This is a hack to work around a bug in Ruby 1.9.3p0:
  # http://redmine.ruby-lang.org/issues/5564
  #
  # Basically, at runtime we may need to perform some encoding conversions on the templates,
  # but if the converter hasn't been loaded by Ruby beforehand (i.e. now), then it won't be
  # able to find it (due to a  bug).
  #
  # However, we don't know what conversions we may need to do a runtime. So we load up a
  # marshal-dumped structure which contains a pre-generated list of all the possible conversions,
  # and we load all of them.
  #
  # In my testing this increased the process size by about 3.9 MB (after the conversions array
  # is GC'd) and took around 170ms to run, which seems acceptable for a workaround.
  #
  # The script to dump the conversions is: https://gist.github.com/1342729

  filename    = File.join(File.dirname(__FILE__), 'data', 'encoding_conversions.dump')
  conversions = Marshal.load(File.read(filename))
  conversions.each do |from, to_array|
    to_array.each do |to|
      Encoding::Converter.new(from, to)
    end
  end
end

I seem to have a hit a bit of a (WE)Brick wall, and have no idea where to go from here (except maybe a Linux VM).

Any help would be greatly appreciated.

LJ

I have a hash that looks something like this:

params = { :irrelevant => "A String",
           :choice1 => "Oh look, another o...More

Here's the situation:

I have SSH access to ServerA

I have SFTP access to ServerB, but only from ServerA

I want to use Ruby t...More

Here's the situation:

I have SSH access to ServerA

I have SFTP access to ServerB, but only from ServerA

I want to use Ruby to SSH into ServerA, then SFTP files from ServerB to ServerA.

I can connect to ServerA using the documentation from Net::SSH:

require 'net/ssh/gateway'

gateway = Net::SSH::Gateway.new('server_a', 'user')

gateway.ssh("server_a", "user") do |ssh|
  # how to SFTP into server_b here and run SFTP commands?
end

gateway.shutdown!

What I can't figure out is how to SFTP into ServerB from the context of ServerA?

Has much changed with the release of Bundler? Is there a template that can be used as a base? What are the best practices?

Here's the situation:

I have SSH access to ServerA

I have SFTP access to ServerB, but only from ServerA

I want to use Ruby to SSH into ServerA, then SFTP files from ServerB to ServerA.

I can connect to ServerA using the documentation from Net::SSH:

require 'net/ssh/gateway'

gateway = Net::SSH::Gateway.new('server_a', 'user')

gateway.ssh("server_a", "user") do |ssh|
  # how to SFTP into server_b here and run SFTP commands?
end

gateway.shutdown!

What I can't figure out is how to SFTP into ServerB from the context of ServerA?

Given I have an array of 3 strings:

["Extra tv in bedroom",
 "Extra tv in living room",
 "Extra tv outside the shop"]

Given I have an array of 3 strings:

["Extra tv in bedroom",
 "Extra tv in living room",
 "Extra tv outside the shop"]

How do I find the longest string all strings have in common?

I have a script with a factory method that I would like to return a different implementation of some class depending on whether or not the script is...More

I have a script with a factory method that I would like to return a different implementation of some class depending on whether or not the script is running from JRuby or Ruby. Anyone have any ideas on how I could tell the difference from inside my script?

Some initial thoughts I had were:

• Attempt to 'include Java' and rescue back to the Ruby implementation if it fails. This method doesn't work. Ruby's smart enough to error out regardless of my begin/rescue/end.

• Do something goofy with process IDs. I'd rather avoid this, since it always feels like a hack.

Thanks for any and all ideas.

I have two models, Users and Groups. Each group can have many users and each user can be in many groups.

I currently have something simple l...More

I have two models, Users and Groups. Each group can have many users and each user can be in many groups.

I currently have something simple like:

User:

has_many    :groups

Group:

has_many    :users

So I have a groups_users table which is just creating rows with group_id and user_id. I want to add another column to this, (which I have), the question is how do I access it from a model without using a custom SQL call? In the group model I can go self.users and in user I can go self.groups

Is there a way to change the third column in this table from a user model?

Sorry if this is confusing, please advise on this

I am having trouble getting this to work so any help would be appreciated! Basically, the request.body contains valid XML for the Web Service like s...More

I am having trouble getting this to work so any help would be appreciated! Basically, the request.body contains valid XML for the Web Service like so:

<somedata>
<name>Test Name 1</name>
<description>Some data for Unit testing</description>
</somedata>

...but the service returns empty XML. Note that the id field is returned suggesting that it does actually hit the database, but the name and description fields are nil:

<somedata>
<id type='integer'>1</id>
<name nil='true'></name>
<description nil='true'></description>
</somedata>

I have manually tested the RESTFUL service using Poster and it works fine.

Here is the code:

url = URI.parse('http://localhost:3000/someservice/')
request = Net::HTTP::Post.new(url.path)
request.body = "<?xml version='1.0' encoding='UTF-8'?><somedata><name>Test Name 1</name><description>Some data for Unit testing</description></somedata>"
response = Net::HTTP.start(url.host, url.port) {|http| http.request(request)}

#Note this test PASSES!
assert_equal '201 Created', response.get_fields('Status')[0]

Does anyone have any clues why the data in the XML post is not persisted?