fix(puzzles): Better handle GenerateSlackThread job errors and incomp…

…lete puzzle data (#719)

* feat(errors): create SlackError class

* fix(puzzles): improve GenerateSlackThread

* feat(tasks): create rake task to update puzzle thread

* fix(puzzles): better handle missing puzzle data

* fix(puzzles): wrap rake instruction in code block

* fix: rubocop

* Fix typo

---------

Co-authored-by: Jérémie Bonal <jeremie.bonal@gmail.com>

app/controllers/snippets_controller.rb

@@ -79,6 +79,8 @@ def client
 
   def post_slack_message
     puzzle = Puzzle.by_date(Aoc.begin_time.change(day: params[:day]))
+    return if puzzle.thread_ts.nil?
+
     username = "<#{helpers.profile_url(current_user.uid)}|#{current_user.username}>"
     text = "#{username} submitted a new #{solution_markdown} for part #{params[:challenge]} in :#{@snippet.language}-hd:"
     client.chat_postMessage(channel: ENV.fetch("SLACK_CHANNEL", "#aoc-dev"), text:, thread_ts: puzzle.thread_ts)

app/errors/slack_error.rb

@@ -0,0 +1,3 @@
+# frozen_string_literal: true
+
+class SlackError < StandardError; end

app/jobs/generate_slack_thread.rb

@@ -5,50 +5,69 @@
 class GenerateSlackThread < ApplicationJob
   queue_as :default
 
+  retry_on SlackError do |_, error|
+    client.chat_postMessage(channel: "#aoc-dev", text: error)
+  end
+
   def perform(date)
     @puzzle = Puzzle.find_or_create_by(date:)
+    return if @puzzle.slack_url.present?
 
-    if @puzzle.title ||= title_scraped
-      post_message(channel: ENV.fetch("SLACK_CHANNEL", "#aoc-dev"), text: @puzzle.title)
-      @puzzle.slack_url = save_permalink
-      @puzzle.thread_ts = @message["message"]["ts"]
-      @puzzle.save
+    if @puzzle.persisted?
+      @puzzle.title = scraped_title || "`SPOILER` <#{@puzzle.url}|Day #{date.day}>"
+      @puzzle.thread_ts = message["message"]["ts"]
+      @puzzle.slack_url = permalink
+      @puzzle.save!
     else
-      post_message(channel: "#aoc-dev", text: "Title not found for day ##{@puzzle.date.day}")
-      @puzzle.destroy
+      client.chat_postMessage(channel: "#aoc-dev", text: @puzzle.errors.full_messages.join(", "))
     end
   end
 
   private
 
+  def channel
+    ENV.fetch("SLACK_CHANNEL", "#aoc-dev")
+  end
+
   def client
     @client ||= Slack::Web::Client.new
   end
 
-  def post_message(channel:, text:)
-    # https://api.slack.com/methods/chat.postMessage
-    @message = client.chat_postMessage(channel:, text:)
+  def message
+    @message ||= if @puzzle.thread_ts.present?
+                   { "message" => { "ts" => @puzzle.thread_ts } }
+                 else
+                   response = client.chat_postMessage(channel:, text: @puzzle.title)
+                   raise SlackError.new, "Failed to post message for day ##{@puzzle.date.day}" unless response["ok"]
+
+                   response
+                 end
   end
 
-  def save_permalink
-    # https://api.slack.com/methods/chat.getPermalink
-    slack_thread = client.chat_getPermalink(
-      channel: @message["channel"],
-      message_ts: @message["message"]["ts"]
-    )
+  def permalink
+    @permalink ||= begin
+      response = client.chat_getPermalink(channel:, message_ts: message["message"]["ts"])[:permalink]
+      raise SlackError.new, "Failed to get permalink for day ##{@puzzle.date.day}" unless response["ok"]
 
-    slack_thread[:permalink] || Aoc.slack_channel
+      response
+    end
   end
 
-  def title_scraped
-    @title_scraped ||= begin
+  def scraped_title
+    @scraped_title ||= begin
       html = URI.parse(@puzzle.url).open
       doc = Nokogiri::HTML(html)
       titles = doc.css("h2").map(&:text)
       raw_title = titles.find { |title| title.match?(/--- Day \d+:/) }
 
       "`SPOILER` <#{@puzzle.url}|#{raw_title.gsub('---', '').strip}>" if raw_title.present?
     rescue OpenURI::HTTPError
+      day = @puzzle.date.day
+      client.chat_postMessage(
+        channel: "#aoc-dev",
+        text: "Title not found for day ##{day}, run `bundle exec rake 'update_puzzle_thread[#{day},#{channel}]'`"
+      )
+
       nil
     end
   end

app/views/days/show.html.erb

@@ -11,7 +11,7 @@
       <span>·</span>
       <%= link_to "puzzle", Aoc.url(@day), target: :_blank, rel: :noopener, class: "link-explicit link-external" %>
 
-      <% if @puzzle.present? %>
+      <% if @puzzle.slack_url.present? %>
         <span>·</span>
         <%= link_to "slack thread", @puzzle.slack_url, target: :_blank, rel: :noopener, class: "link-explicit link-slack" %>
       <% end %>

lib/tasks/update_puzzle_thread.rake

@@ -0,0 +1,23 @@
+# frozen_string_literal: true
+
+desc "update_puzzle_thread"
+task :update_puzzle_thread, %i[day channel] => :environment do |_, args|
+  next p "day param missing" if args[:day].nil?
+  next p "channel missing or incorrect" unless args[:channel].in? %w[aoc aoc-dev]
+
+  puzzle = Puzzle.by_date(Aoc.begin_time.change(day: args[:day]))
+  next p "Puzzle not found" if puzzle.nil?
+
+  html = URI.parse(@puzzle.url).open
+  doc = Nokogiri::HTML(html)
+  titles = doc.css("h2").map(&:text)
+  raw_title = titles.find { |title| title.match?(/--- Day \d+:/) }
+  next p "Title not found" if raw_title.nil?
+
+  client = Slack::Web::Client.new
+  text = "`SPOILER` <#{@puzzle.url}|#{raw_title.gsub('---', '').strip}>"
+  response = client.chat_update(channel: args[:channel], ts: puzzle.thread_ts, text:)
+  next p "Failed to update message" unless response["ok"]
+
+  puzzle.update!(title: text)
+end