How to write a while loop properly - ruby

Question

I'm trying to scrape a website however I cannot seem to get my while-loop to break out once it hits a page with no more information:
def scrape_verse_items(keyword)
pg = 1
while pg < 1000
puts "page #{pg}"
url = "https://www.bible.com/search/bible?page=#{pg}&q=#{keyword}&version_id=1"
doc = Nokogiri::HTML(open(url))
items = doc.css("ul.search-result li.reference")
error = doc.css('div#noresults')
until error.any? do
if keyword != ''
item_hash = {}
items.each do |item|
title = item.css("h3").text.strip
content = item.css("p").text.strip
item_hash[title] = content
end
else
puts "Please enter a valid search"
end
if error.any?
break
end
end
pg += 1
end
item_hash
end
puts scrape_verse_items('joy')

Answer 1

I know this doesn't exactly answer your question, but perhaps you might consider using a different approach altogether.
Using while and until loops can get a bit confusing, and usually isn't the most performant way of doing things.
Maybe you would consider using recursion instead.
I've written a small script that seems to work :
class MyScrapper
def initialize;end
def call(keyword)
puts "Please enter a valid search" && return unless keyword
scrape({}, keyword, 1)
end
private
def scrape(results, keyword, page)
doc = load_page(keyword, page)
return results if doc.css('div#noresults').any?
build_new_items(doc).merge(scrape(results, keyword, page+1))
end
def load_page(keyword, page)
url = "https://www.bible.com/search/bible?page=#{page}&q=#{keyword}&version_id=1"
Nokogiri::HTML(open(url))
end
def build_new_items(doc)
items = doc.css("ul.search-result li.reference")
items.reduce({}) do |list, item|
title = item.css("h3").text.strip
content = item.css("p").text.strip
list[title] = content
list
end
end
end
You call it by doing MyScrapper.new.call("Keyword") (It might make more sense to have this as a module you include or even have them as class methods to avoid the need to instantiate the class.
What this does is, call a method called scrape and you give it the starting results, keyword, and page. It loads the page, if there are no results it returns the existing results it has found.
Otherwise it builds a hash from the page it loaded, and then the method calls itself, and merges the results with the new hash it just build. It does this till there are no more results.
If you want to limit the page results you can just change this like:
return results if doc.css('div#noresults').any?
to this:
return results if doc.css('div#noresults').any? || page > 999
Note: You might want to double-check the results that are being returned are correct. I think they should be but I wrote this quite quickly, so there could always be a small bug hiding somewhere in there.