From f5243ea844f39710fd29ca964ab53bf4299388c0 Mon Sep 17 00:00:00 2001
From: Jeremy Friesen <jeremy.n.friesen@gmail.com>
Date: Tue, 16 Nov 2021 11:12:01 -0500
Subject: [PATCH] Normalizing feed page size (#15326)

This commit removes a handful of magic numbers and instead relies on a
constant.

This has a small impact in that the Basic feed will now return 50
articles instead of 25.  However, normalizing the feed pagination window
size helps reduce some oddities in reporting.

In addition, this might be something we consider giving administrators
the ability to set (with default options, because we shouldn't allow
page sizes of 10_000 as that's a massive memory hog).

Related to #14709
---
 app/models/article.rb                                   | 2 ++
 app/services/articles/feeds/basic.rb                    | 2 +-
 app/services/articles/feeds/large_forem_experimental.rb | 2 +-
 app/services/articles/feeds/latest.rb                   | 2 +-
 app/services/articles/feeds/tag.rb                      | 2 +-
 app/services/articles/feeds/timeframe.rb                | 2 +-
 6 files changed, 7 insertions(+), 5 deletions(-)

diff --git a/app/models/article.rb b/app/models/article.rb
index 7c43ed016..42f81cece 100644
--- a/app/models/article.rb
+++ b/app/models/article.rb
@@ -9,6 +9,8 @@ class Article < ApplicationRecord
   acts_as_taggable_on :tags
   resourcify
 
+  DEFAULT_FEED_PAGINATION_WINDOW_SIZE = 50
+
   attr_accessor :publish_under_org
   attr_writer :series
 
diff --git a/app/services/articles/feeds/basic.rb b/app/services/articles/feeds/basic.rb
index 69de65ddb..88f1e909e 100644
--- a/app/services/articles/feeds/basic.rb
+++ b/app/services/articles/feeds/basic.rb
@@ -1,7 +1,7 @@
 module Articles
   module Feeds
     class Basic
-      def initialize(user: nil, number_of_articles: 25, page: 1, tag: nil)
+      def initialize(user: nil, number_of_articles: Article::DEFAULT_FEED_PAGINATION_WINDOW_SIZE, page: 1, tag: nil)
         @user = user
         @number_of_articles = number_of_articles
         @page = page
diff --git a/app/services/articles/feeds/large_forem_experimental.rb b/app/services/articles/feeds/large_forem_experimental.rb
index 05d5cf148..93694834e 100644
--- a/app/services/articles/feeds/large_forem_experimental.rb
+++ b/app/services/articles/feeds/large_forem_experimental.rb
@@ -1,7 +1,7 @@
 module Articles
   module Feeds
     class LargeForemExperimental
-      def initialize(user: nil, number_of_articles: 50, page: 1, tag: nil)
+      def initialize(user: nil, number_of_articles: Article::DEFAULT_FEED_PAGINATION_WINDOW_SIZE, page: 1, tag: nil)
         @user = user
         @number_of_articles = number_of_articles
         @page = page
diff --git a/app/services/articles/feeds/latest.rb b/app/services/articles/feeds/latest.rb
index e6908df31..3e0182127 100644
--- a/app/services/articles/feeds/latest.rb
+++ b/app/services/articles/feeds/latest.rb
@@ -3,7 +3,7 @@ module Articles
     module Latest
       MINIMUM_SCORE = -20
 
-      def self.call(tag: nil, number_of_articles: 50, page: 1)
+      def self.call(tag: nil, number_of_articles: Article::DEFAULT_FEED_PAGINATION_WINDOW_SIZE, page: 1)
         Articles::Feeds::Tag.call(tag)
           .order(published_at: :desc)
           .where("score > ?", MINIMUM_SCORE)
diff --git a/app/services/articles/feeds/tag.rb b/app/services/articles/feeds/tag.rb
index f3751a395..8bdd6015b 100644
--- a/app/services/articles/feeds/tag.rb
+++ b/app/services/articles/feeds/tag.rb
@@ -1,7 +1,7 @@
 module Articles
   module Feeds
     module Tag
-      def self.call(tag = nil, number_of_articles: 50, page: 1)
+      def self.call(tag = nil, number_of_articles: Article::DEFAULT_FEED_PAGINATION_WINDOW_SIZE, page: 1)
         articles =
           if tag.present?
             if FeatureFlag.enabled?(:optimize_article_tag_query)
diff --git a/app/services/articles/feeds/timeframe.rb b/app/services/articles/feeds/timeframe.rb
index 944b04e8e..9c65ca214 100644
--- a/app/services/articles/feeds/timeframe.rb
+++ b/app/services/articles/feeds/timeframe.rb
@@ -1,7 +1,7 @@
 module Articles
   module Feeds
     module Timeframe
-      def self.call(timeframe, tag: nil, number_of_articles: 50, page: 1)
+      def self.call(timeframe, tag: nil, number_of_articles: Article::DEFAULT_FEED_PAGINATION_WINDOW_SIZE, page: 1)
         articles = ::Articles::Feeds::Tag.call(tag)
 
         articles