Prefill original title and content from projecteuler.net

app/jobs/pull_problem_content_job.rb

@@ -0,0 +1,21 @@
+require 'open-uri'
+
+class PullProblemContentJob < ApplicationJob
+  queue_as :default
+
+  def perform(problem)
+    html = URI.open("https://projecteuler.net/minimal=#{problem.id}").read
+    html.strip!
+
+    # Linked problems
+    html.gsub!('<a href="problem=', '<a href="/problem=')
+    # Linked about pages
+    html.gsub!('<a href="about=', '<a href="/about=')
+    # Linked txt resources
+    html.gsub!('<a href="project/resources/', '<a href="https://projecteuler.net/project/resources/')
+    # Included images
+    html.gsub!('<img src="project/images/', '<img src="https://projecteuler.net/project/images/')
+
+    problem.update(original_content: html, pulled_at: Time.current())
+  end
+end

app/jobs/pull_problems_job.rb

@@ -0,0 +1,23 @@
+require 'csv'
+require 'open-uri'
+
+class PullProblemsJob < ApplicationJob
+  queue_as :default
+
+  PULL_URL = "https://projecteuler.net/minimal=problems;csv"
+
+  def perform
+    csv = CSV.parse(URI.open(PULL_URL), headers: [:id, :title, :date_published, :date_last_updated, :solved_by])
+    csv.each do |row|
+      id = row[:id].to_i
+      last_updated = Time.at(row[:date_last_updated].to_i)
+      problem = Problem.where(id: id).first_or_create!
+      if problem.pulled_at.nil? or problem.pulled_at < last_updated
+        original_title = row[:title]
+        problem.update(original_title: original_title)
+        # Don't update pulled_at yet until we also successfully pulled the original_content
+        PullProblemContentJob.perform_later problem
+      end
+    end
+  end
+end