Merge pull request #1758 from codetriage/schneems/poke-inactive-update

Update poke-inactive mailer

Author: schneems

app/mailers/user_mailer.rb

@@ -75,14 +75,22 @@ def send_triage(user:, assignment:, repo:, create: false)
     mail(to: @user.email, reply_to: "[email protected]", subject: "[CodeTriage] Help triage #{@repo.full_name}")
   end
 
-  def poke_inactive(user:, repos_by_need_ids:)
+  def poke_inactive(user:, min_issue_count:, min_subscriber_count:)
     return unless set_and_check_user(user)
-    @most_repo = Repo.order_by_issue_count.first
+    languages = @user.favorite_languages&.sort || []
 
-    repo_need_id = repos_by_need_ids.detect { |id| id != @most_repo.id }
-    @need_repo = Repo.where(id: repo_need_id).first
+    query = Repo
+    query = repo.where(language: languages) if !languages.empty?
+    query = query
+            .where("issues_count >= ?", min_issue_count)
+            .where("subscribers_count >= ?", min_subscriber_count)
+
+    @repos = Random::CachedIdQuery.new(
+      query: query,
+      limit: 3,
+      expires_in: 24.hours
+    ).call
 
-    @random_repo = Repo.rand.not_in(@most_repo.id, @need_repo.id).first || @most_repo || @need_repo
     mail(to: @user.email, reply_to: "[email protected]", subject: "CodeTriage misses you")
   end
 

app/models/random/cached_id_query.rb

@@ -0,0 +1,30 @@
+# Provides an actual random result exactly as expected
+# but it's cached for a period of time.
+#
+# Cache keys expire after the set time but
+# are unbounded. Take care to not pass in arbitrary data
+# from users into the query.
+#
+# The raw SQL is used for a cache key so take care
+# to pass in values in sorted order etc.
+#
+# The first run of this is VERY expensive on a large
+# model and can still cause significant database load
+class Random::CachedIdQuery
+  private attr_reader :limit, :query, :key, :expires_in
+
+  def initialize(query:, limit:, expires_in:)
+    @query = query.order("RANDOM()")
+    @key = "random_cached_query:#{@query.to_sql.hash}"
+    @expires_in = expires_in
+    @limit = limit
+  end
+
+  def call
+    ids = Rails.cache.fetch(key, expires_in: expires_in) do
+      query.select(:id).first(limit).map(&:id)
+    end
+
+    query.klass.where(id: ids)
+  end
+end

app/models/repo.rb

@@ -115,10 +115,6 @@ def weight
     end
   end
 
-  def subscriber_count
-    users.count
-  end
-
   # pulls out number of issues divided by number of subscribers
   def self.order_by_need
     joins(:repo_subscriptions)
@@ -135,13 +131,6 @@ def self.not_in(*ids)
     where("repos.id not in (?)", ids)
   end
 
-  @@max_id = nil
-  def self.rand
-    @@max_id = self.maximum(:id) if @@max_id.nil?
-
-    where("id >= ?", Random.new.rand(1..@@max_id))
-  end
-
   def self.all_languages
     self.select("language").group("language").order("language ASC").map(&:language).reject(&:blank?)
   end

app/models/user.rb

@@ -103,7 +103,10 @@ def auth_is_valid?
   end
 
   @@max_id = nil
-  def self.random
+
+  # Much faster than order("RANDOM()") but it's
+  # not guaranteed to return results
+  def self.fast_rand
     @@max_id = self.maximum(:id) if @@max_id.nil?
 
     where("id >= ?", Random.new.rand(1..@@max_id))

app/views/user_mailer/poke_inactive.html.erb

@@ -0,0 +1,34 @@
+Hello <%= @user.github %>,
+
+You're getting this email because you've signed up for [CodeTriage](<%= root_url %>), but haven't subscribed to any repos yet. Here are some tips for getting started.
+
+### Tips and tricks
+
+- Open source tip: Not sure how to get started? Read [picking the right repo](https://www.codetriage.com/university/picking_a_repo) from the [CodeTriage University](<%= university_index_url %>).
+- Open source tip: More of a visual learner? [Watch Richard triage issues in real time](https://www.schneems.com/2020/09/22/triage-with-me-11-issues-2-prs-in-15-hours/) (about 7 minutes per issue) from the [CodeTriage University](<%= university_index_url %>).
+- Want more? The ["How to Open Source" is a comprehensive contribution manual](https://howtoopensource.dev/). Click through for a free sample chapter.
+
+### Suggested repos
+
+<% @repos.each do |repo| %>
+- **<%= repo.language %>: <%= repo.full_name %>** ([Subscribe](<%= repo_url(repo) %>))
+<% end %>
+
+If you don't like any of those [add your own repo](<%= new_repo_url %>) or [browse all repos](<%= root_url %>).
+
+<% if @user.favorite_languages.blank? %>
+
+### Tell us your favorite progrmaming languages
+
+CodeTriage can help you pick a repo. All you have to do is tell us the programming language(s) you most commonly use:
+
+[Select your favorite languages(s)](user_url(@user))
+
+<% end %>
+
+### See you next week
+
+Subscribe to a repo, or you will get this same email next week, maybe with different suggestions. To unsubscribe entirely, [delete your account](<%= user_url(@user) %>), but don't do that, subscribe to a repo and start your open source journey. We believe in you!
+
+--
+For open source tips, follow [@HowToOpenSource](https://twitter.com/HowToOpenSource) on Twitter.

app/views/user_mailer/poke_inactive.md.erb

@@ -33,7 +33,7 @@ def call
     @mutex.synchronize do
       return if @keys.any?
 
-      @keys = User.random.where.not(token: nil).limit(5000).pluck(:token)
+      @keys = User.fast_rand.where.not(token: nil).limit(5000).pluck(:token)
 
       if @keys.empty? && User.where.not(token: nil).empty?
         raise "No users with tokens in the database"

app/views/user_mailer/poke_inactive.text.erb

@@ -0,0 +1,5 @@
+class AddIndexSubscriberCount < ActiveRecord::Migration[7.0]
+  def change
+    add_index :repos, :subscribers_count
+  end
+end

config/initializers/git_hub_bub.rb

@@ -10,7 +10,7 @@
 #
 # It's strongly recommended that you check this file into your version control system.
 
-ActiveRecord::Schema[7.0].define(version: 2022_10_13_212959) do
+ActiveRecord::Schema[7.0].define(version: 2022_12_28_065556) do
   # These are extensions that must be enabled in order to support this database
   enable_extension "pg_stat_statements"
   enable_extension "plpgsql"
@@ -161,6 +161,7 @@
     t.index ["issues_count"], name: "index_repos_on_issues_count"
     t.index ["language"], name: "index_repos_on_language"
     t.index ["name", "user_name"], name: "index_repos_on_name_and_user_name", unique: true
+    t.index ["subscribers_count"], name: "index_repos_on_subscribers_count"
     t.index ["user_name"], name: "index_repos_on_user_name"
   end