From 3bfd41eba9dff830bd7a0e22727fe999e92cffea Mon Sep 17 00:00:00 2001
From: Zach Gollwitzer <zach.gollwitzer@gmail.com>
Date: Sat, 17 May 2025 16:14:28 -0400
Subject: [PATCH] Materializers

---
 app/models/balance/{syncer.rb => materializer.rb}      | 10 +++++-----
 app/models/holding/{syncer.rb => materializer.rb}      |  6 ++++--
 .../balance/{syncer_test.rb => materializer_test.rb}   |  8 ++++----
 .../holding/{syncer_test.rb => materializer_test.rb}   |  6 +++---
 4 files changed, 16 insertions(+), 14 deletions(-)
 rename app/models/balance/{syncer.rb => materializer.rb} (89%)
 rename app/models/holding/{syncer.rb => materializer.rb} (87%)
 rename test/models/balance/{syncer_test.rb => materializer_test.rb} (82%)
 rename test/models/holding/{syncer_test.rb => materializer_test.rb} (78%)

diff --git a/app/models/balance/syncer.rb b/app/models/balance/materializer.rb
similarity index 89%
rename from app/models/balance/syncer.rb
rename to app/models/balance/materializer.rb
index 890bb5f9..75a98ffd 100644
--- a/app/models/balance/syncer.rb
+++ b/app/models/balance/materializer.rb
@@ -1,4 +1,4 @@
-class Balance::Syncer
+class Balance::Materializer
   attr_reader :account, :strategy
 
   def initialize(account, strategy:)
@@ -6,9 +6,9 @@ class Balance::Syncer
     @strategy = strategy
   end
 
-  def sync_balances
+  def materialize_balances
     Balance.transaction do
-      sync_holdings
+      materialize_holdings
       calculate_balances
 
       Rails.logger.info("Persisting #{@balances.size} balances")
@@ -23,8 +23,8 @@ class Balance::Syncer
   end
 
   private
-    def sync_holdings
-      @holdings = Holding::Syncer.new(account, strategy: strategy).sync_holdings
+    def materialize_holdings
+      @holdings = Holding::Materializer.new(account, strategy: strategy).materialize_holdings
     end
 
     def update_account_info
diff --git a/app/models/holding/syncer.rb b/app/models/holding/materializer.rb
similarity index 87%
rename from app/models/holding/syncer.rb
rename to app/models/holding/materializer.rb
index 345f2a3f..e4931128 100644
--- a/app/models/holding/syncer.rb
+++ b/app/models/holding/materializer.rb
@@ -1,10 +1,12 @@
-class Holding::Syncer
+# "Materializes" holdings (similar to a DB materialized view, but done at the app level)
+# into a series of records we can easily query and join with other data.
+class Holding::Materializer
   def initialize(account, strategy:)
     @account = account
     @strategy = strategy
   end
 
-  def sync_holdings
+  def materialize_holdings
     calculate_holdings
 
     Rails.logger.info("Persisting #{@holdings.size} holdings")
diff --git a/test/models/balance/syncer_test.rb b/test/models/balance/materializer_test.rb
similarity index 82%
rename from test/models/balance/syncer_test.rb
rename to test/models/balance/materializer_test.rb
index 648f6b3a..4a5ac439 100644
--- a/test/models/balance/syncer_test.rb
+++ b/test/models/balance/materializer_test.rb
@@ -1,6 +1,6 @@
 require "test_helper"
 
-class Balance::SyncerTest < ActiveSupport::TestCase
+class Balance::MaterializerTest < ActiveSupport::TestCase
   include EntriesTestHelper
 
   setup do
@@ -14,7 +14,7 @@ class Balance::SyncerTest < ActiveSupport::TestCase
   end
 
   test "syncs balances" do
-    Holding::Syncer.any_instance.expects(:sync_holdings).returns([]).once
+    Holding::Materializer.any_instance.expects(:materialize_holdings).returns([]).once
 
     @account.expects(:start_date).returns(2.days.ago.to_date)
 
@@ -26,7 +26,7 @@ class Balance::SyncerTest < ActiveSupport::TestCase
     )
 
     assert_difference "@account.balances.count", 2 do
-      Balance::Syncer.new(@account, strategy: :forward).sync_balances
+      Balance::Materializer.new(@account, strategy: :forward).materialize_balances
     end
   end
 
@@ -45,7 +45,7 @@ class Balance::SyncerTest < ActiveSupport::TestCase
     )
 
     assert_difference "@account.balances.count", 3 do
-      Balance::Syncer.new(@account, strategy: :forward).sync_balances
+      Balance::Materializer.new(@account, strategy: :forward).materialize_balances
     end
   end
 end
diff --git a/test/models/holding/syncer_test.rb b/test/models/holding/materializer_test.rb
similarity index 78%
rename from test/models/holding/syncer_test.rb
rename to test/models/holding/materializer_test.rb
index 19e191c8..41ae8ff6 100644
--- a/test/models/holding/syncer_test.rb
+++ b/test/models/holding/materializer_test.rb
@@ -1,6 +1,6 @@
 require "test_helper"
 
-class Holding::SyncerTest < ActiveSupport::TestCase
+class Holding::MaterializerTest < ActiveSupport::TestCase
   include EntriesTestHelper
 
   setup do
@@ -14,7 +14,7 @@ class Holding::SyncerTest < ActiveSupport::TestCase
 
     # Should have yesterday's and today's holdings
     assert_difference "@account.holdings.count", 2 do
-      Holding::Syncer.new(@account, strategy: :forward).sync_holdings
+      Holding::Materializer.new(@account, strategy: :forward).materialize_holdings
     end
   end
 
@@ -23,7 +23,7 @@ class Holding::SyncerTest < ActiveSupport::TestCase
     Holding.create!(account: @account, security: @aapl, qty: 1, price: 100, amount: 100, currency: "USD", date: Date.current)
 
     assert_difference "Holding.count", -1 do
-      Holding::Syncer.new(@account, strategy: :forward).sync_holdings
+      Holding::Materializer.new(@account, strategy: :forward).materialize_holdings
     end
   end
 end