Rails4：NameError：未初始化的常数Net-Heroku

Question

Building a rails web scraper application that will return the current water supplier based on a UK postcode (eg: EC2A 4BX). Created an initializer file and it works on local host but on Heroku I get error. NameError: uninitialized constant Net

Preparing app for Rails asset pipeline
remote:        Running: rake assets:precompile
remote:        rake aborted!
remote:        NameError: uninitialized constant Net
remote:        /tmp/build_b54ea2f35a53dd4aa97f18e85d315c40/config/initializers/thameswater.rb:10:in `<top (required)>'
remote:        /tmp/build_b54ea2f35a53dd4aa97f18e85d315c40/vendor/bundle/ruby/2.0.0/gems/railties-4.1.7/lib/rails/engine.rb:648:in `block in load_config_initializer'
remote:        /tmp/build_b54ea2f35a53dd4aa97f18e85d315c40/vendor/bundle/ruby/2.0.0/gems/activesupport-4.1.7/lib/active_support/notifications.rb:161:in `instrument'
remote:        /tmp/build_b54ea2f35a53dd4aa97f18e85d315c40/vendor/bundle/ruby/2.0.0/gems/railties-4.1.7/lib/rails/engine.rb:647:in `load_config_initializer'
remote:        /tmp/build_b54ea2f35a53dd4aa97f18e85d315c40/vendor/bundle/ruby/2.0.0/gems/railties-4.1.7/lib/rails/engine.rb:612:in `block (2 levels) in <class:Engine>'
remote:        /tmp/build_b54ea2f35a53dd4aa97f18e85d315c40/vendor/bundle/ruby/2.0.0/gems/railties-4.1.7/lib/rails/engine.rb:611:in `each'
remote:        /tmp/build_b54ea2f35a53dd4aa97f18e85d315c40/vendor/bundle/ruby/2.0.0/gems/railties-4.1.7/lib/rails/engine.rb:611:in `block in <class:Engine>'
remote:        /tmp/build_b54ea2f35a53dd4aa97f18e85d315c40/vendor/bundle/ruby/2.0.0/gems/railties-4.1.7/lib/rails/initializable.rb:30:in `instance_exec'
remote:        /tmp/build_b54ea2f35a53dd4aa97f18e85d315c40/vendor/bundle/ruby/2.0.0/gems/railties-4.1.7/lib/rails/initializable.rb:30:in `run'
remote:        /tmp/build_b54ea2f35a53dd4aa97f18e85d315c40/vendor/bundle/ruby/2.0.0/gems/railties-4.1.7/lib/rails/initializable.rb:55:in `block in run_initializers'
remote:        /tmp/build_b54ea2f35a53dd4aa97f18e85d315c40/vendor/bundle/ruby/2.0.0/gems/railties-4.1.7/lib/rails/initializable.rb:44:in `each'
remote:        /tmp/build_b54ea2f35a53dd4aa97f18e85d315c40/vendor/bundle/ruby/2.0.0/gems/railties-4.1.7/lib/rails/initializable.rb:44:in `tsort_each_child'
remote:        /tmp/build_b54ea2f35a53dd4aa97f18e85d315c40/vendor/bundle/ruby/2.0.0/gems/railties-4.1.7/lib/rails/initializable.rb:54:in `run_initializers'
remote:        /tmp/build_b54ea2f35a53dd4aa97f18e85d315c40/vendor/bundle/ruby/2.0.0/gems/railties-4.1.7/lib/rails/application.rb:300:in `initialize!'
remote:        /tmp/build_b54ea2f35a53dd4aa97f18e85d315c40/config/environment.rb:5:in `<top (required)>'
remote:        /tmp/build_b54ea2f35a53dd4aa97f18e85d315c40/vendor/bundle/ruby/2.0.0/gems/railties-4.1.7/lib/rails/application.rb:276:in `require_environment!'
remote:        /tmp/build_b54ea2f35a53dd4aa97f18e85d315c40/vendor/bundle/ruby/2.0.0/gems/railties-4.1.7/lib/rails/application.rb:389:in `block in run_tasks_blocks'


require 'open-uri'
require 'nokogiri'


#Store URL to be scraped

uri = URI.parse('https://secure.thameswater.co.uk/dynamic/cps/rde/xchg/corp/hs.xsl/Thames_Water_Supply.xml')


https = Net::HTTP.new(uri.host,uri.port)   **<---Error**
https.verify_mode = OpenSSL::SSL::VERIFY_NONE
https.use_ssl = true

# we need to define a Post object and send the postcode to search
req = Net::HTTP::Post.new(uri.path)
req.set_form_data('postcode1' => 'RG1 8DB')

# do the post
result = https.request(req)

supplied = 'http://www.thameswater.co.uk/your-account/605_5460.htm'
not_supplied = 'http://www.thameswater.co.uk/your-account/605_5459.htm'

# evaluates the post result
if result.header['Location'] == supplied
  puts 'Your property is in our supply area'
elsif result.header['Location'] == not_supplied
  puts 'Sorry, we cant find your postcode'
end

Answer 1

Add to your config/initializers/thameswater.rb :

require 'open-uri'
require 'nokogiri'
require 'net/http'

#Store URL to be scraped

uri = URI.parse('https://secure.thameswater.co.uk/dynamic/cps/rde/xchg/corp/hs.xsl/Thames_Water_Supply.xml')
# other code here