Add first class component cache

.tool-versions

@@ -1 +1,2 @@
 ruby 4.0.1
+

Gemfile.lock

@@ -3,6 +3,7 @@ PATH
   specs:
     view_component (4.4.0)
       actionview (>= 7.1.0)
+      actionview_precompiler (>= 0.4)
       activesupport (>= 7.1.0)
       concurrent-ruby (~> 1)
 
@@ -55,6 +56,8 @@ GEM
       erubi (~> 1.11)
       rails-dom-testing (~> 2.2)
       rails-html-sanitizer (~> 1.6)
+    actionview_precompiler (0.4.0)
+      actionview (>= 6.0.a)
     activejob (8.1.2)
       activesupport (= 8.1.2)
       globalid (>= 0.3.6)
@@ -145,6 +148,7 @@ GEM
       temple (>= 0.8.2)
       thor
       tilt
+    herb (0.8.9)
     herb (0.8.9-aarch64-linux-gnu)
     herb (0.8.9-aarch64-linux-musl)
     herb (0.8.9-arm-linux-gnu)
@@ -182,6 +186,7 @@ GEM
     matrix (0.4.3)
     method_source (1.1.0)
     mini_mime (1.1.5)
+    mini_portile2 (2.8.9)
     minitest (6.0.1)
       prism (~> 1.5)
     minitest-mock (5.27.0)
@@ -195,6 +200,9 @@ GEM
     net-smtp (0.5.1)
       net-protocol
     nio4r (2.7.5)
+    nokogiri (1.19.0)
+      mini_portile2 (~> 2.8.2)
+      racc (~> 1.4)
     nokogiri (1.19.0-aarch64-linux-gnu)
       racc (~> 1.4)
     nokogiri (1.19.0-aarch64-linux-musl)
@@ -466,6 +474,7 @@ CHECKSUMS
   actionpack (8.1.2) sha256=ced74147a1f0daafaa4bab7f677513fd4d3add574c7839958f7b4f1de44f8423
   actiontext (8.1.2) sha256=0bf57da22a9c19d970779c3ce24a56be31b51c7640f2763ec64aa72e358d2d2d
   actionview (8.1.2) sha256=80455b2588911c9b72cec22d240edacb7c150e800ef2234821269b2b2c3e2e5b
+  actionview_precompiler (0.4.0) sha256=33b6bd6ec4c1b856e02fdf5f6512c9eb4a92ac1c0545e941b3e354b7d540ed1c
   activejob (8.1.2) sha256=908dab3713b101859536375819f4156b07bdf4c232cc645e7538adb9e302f825
   activemodel (8.1.2) sha256=e21358c11ce68aed3f9838b7e464977bc007b4446c6e4059781e1d5c03bcf33e
   activerecord (8.1.2) sha256=acfbe0cadfcc50fa208011fe6f4eb01cae682ebae0ef57145ba45380c74bcc44
@@ -498,6 +507,7 @@ CHECKSUMS
   ferrum (0.17.1) sha256=51d591120fc593e5a13b5d9d6474389f5145bb92a91e36eab147b5d096c8cbe7
   globalid (1.3.0) sha256=05c639ad6eb4594522a0b07983022f04aa7254626ab69445a0e493aa3786ff11
   haml (7.2.0) sha256=87fd2b71f7feab1724337b090a7d767f5ab2d42f08c974f3ead673f18cfcd55a
+  herb (0.8.9) sha256=8617e7eba753877cef231e3269a7e00788a9b67a91c3b79d1210ae20321b60f7
   herb (0.8.9-aarch64-linux-gnu) sha256=9214cc24953c355f9ae785a95bb9362cdfc9fcd2ae4db2a32bc26c0b88f98c7f
   herb (0.8.9-aarch64-linux-musl) sha256=4ee883eed0935cfe2e508d0843b015d689ef9d13f00e9ec4a81a35acd061dc13
   herb (0.8.9-arm-linux-gnu) sha256=9f83c76899fecd5e3429bbd66728226e7b75539cc59283829041479381a6ceea
@@ -521,13 +531,15 @@ CHECKSUMS
   matrix (0.4.3) sha256=a0d5ab7ddcc1973ff690ab361b67f359acbb16958d1dc072b8b956a286564c5b
   method_source (1.1.0) sha256=181301c9c45b731b4769bc81e8860e72f9161ad7d66dd99103c9ab84f560f5c5
   mini_mime (1.1.5) sha256=8681b7e2e4215f2a159f9400b5816d85e9d8c6c6b491e96a12797e798f8bccef
+  mini_portile2 (2.8.9) sha256=0cd7c7f824e010c072e33f68bc02d85a00aeb6fce05bb4819c03dfd3c140c289
   minitest (6.0.1) sha256=7854c74f48e2e975969062833adc4013f249a4b212f5e7b9d5c040bf838d54bb
   minitest-mock (5.27.0) sha256=7040ed7185417a966920987eaa6eaf1be4ea1fc5b25bb03ff4703f98564a55b0
   net-imap (0.6.2) sha256=08caacad486853c61676cca0c0c47df93db02abc4a8239a8b67eb0981428acc6
   net-pop (0.1.2) sha256=848b4e982013c15b2f0382792268763b748cce91c9e91e36b0f27ed26420dff3
   net-protocol (0.2.2) sha256=aa73e0cba6a125369de9837b8d8ef82a61849360eba0521900e2c3713aa162a8
   net-smtp (0.5.1) sha256=ed96a0af63c524fceb4b29b0d352195c30d82dd916a42f03c62a3a70e5b70736
   nio4r (2.7.5) sha256=6c90168e48fb5f8e768419c93abb94ba2b892a1d0602cb06eef16d8b7df1dca1
+  nokogiri (1.19.0) sha256=e304d21865f62518e04f2bf59f93bd3a97ca7b07e7f03952946d8e1c05f45695
   nokogiri (1.19.0-aarch64-linux-gnu) sha256=11a97ecc3c0e7e5edcf395720b10860ef493b768f6aa80c539573530bc933767
   nokogiri (1.19.0-aarch64-linux-musl) sha256=eb70507f5e01bc23dad9b8dbec2b36ad0e61d227b42d292835020ff754fb7ba9
   nokogiri (1.19.0-arm-linux-gnu) sha256=572a259026b2c8b7c161fdb6469fa2d0edd2b61cd599db4bbda93289abefbfe5

docs/CHANGELOG.md

@@ -10,6 +10,10 @@ nav_order: 6
 
 ## main
 
+* Add experimental support for caching by including `ViewComponent::ExperimentallyCacheable`.
+
+    *Reegan Viljoen*
+
 ## 4.4.0
 
 * Fix segfaults when Ruby coverage is enabled.
@@ -552,7 +556,7 @@ This release makes the following breaking changes:
 
 ## 3.23.0
 
-* Add docs about Slack channel in Ruby Central workspace. (Join us! #oss-view-component). Email joelhawksley@github.com for an invite.
+* Add docs about Slack channel in Ruby Central workspace. (Join us! #oss-view-component). Email <joelhawksley@github.com> for an invite.
 
     *Joel Hawksley
 
@@ -1912,7 +1916,7 @@ Run into an issue with this release? [Let us know](https://github.com/ViewCompon
 
     *Joel Hawksley*
 
-* The ViewComponent team at GitHub is hiring! We're looking for a Rails engineer with accessibility experience: [https://boards.greenhouse.io/github/jobs/4020166](https://boards.greenhouse.io/github/jobs/4020166). Reach out to joelhawksley@github.com with any questions!
+* The ViewComponent team at GitHub is hiring! We're looking for a Rails engineer with accessibility experience: [https://boards.greenhouse.io/github/jobs/4020166](https://boards.greenhouse.io/github/jobs/4020166). Reach out to <joelhawksley@github.com> with any questions!
 
 * The ViewComponent team is hosting a happy hour at RailsConf. Join us for snacks, drinks, and stickers: [https://www.eventbrite.com/e/viewcomponent-happy-hour-tickets-304168585427](https://www.eventbrite.com/e/viewcomponent-happy-hour-tickets-304168585427)
 
@@ -2664,7 +2668,7 @@ Run into an issue with this release? [Let us know](https://github.com/ViewCompon
 
     *Matheus Richard*
 
-* Are you interested in building the future of ViewComponent? GitHub is looking to hire a Senior Engineer to work on Primer ViewComponents and ViewComponent. Apply here: [US/Canada](https://github.com/careers) / [Europe](https://boards.greenhouse.io/github/jobs/3132294). Feel free to reach out to joelhawksley@github.com with any questions.
+* Are you interested in building the future of ViewComponent? GitHub is looking to hire a Senior Engineer to work on Primer ViewComponents and ViewComponent. Apply here: [US/Canada](https://github.com/careers) / [Europe](https://boards.greenhouse.io/github/jobs/3132294). Feel free to reach out to <joelhawksley@github.com> with any questions.
 
     *Joel Hawksley*
 
@@ -2682,7 +2686,7 @@ Run into an issue with this release? [Let us know](https://github.com/ViewCompon
 
 ## 2.31.0
 
-_Note: This release includes an underlying change to Slots that may affect incorrect usage of the API, where Slots were set on a line prefixed by `<%=`. The result of setting a Slot shouldn't be returned. (`<%`)_
+*Note: This release includes an underlying change to Slots that may affect incorrect usage of the API, where Slots were set on a line prefixed by `<%=`. The result of setting a Slot shouldn't be returned. (`<%`)*
 
 * Add `#with_content` to allow setting content without a block.
 
@@ -3130,7 +3134,7 @@ _Note: This release includes an underlying change to Slots that may affect incor
 
   * The gem name is now `view_component`.
   * ViewComponent previews are now accessed at `/rails/view_components`.
-  * ViewComponents can _only_ be rendered with the instance syntax: `render(MyComponent.new)`. Support for all other syntaxes has been removed.
+  * ViewComponents can *only* be rendered with the instance syntax: `render(MyComponent.new)`. Support for all other syntaxes has been removed.
   * ActiveModel::Validations have been removed. ViewComponent generators no longer include validations.
   * In Rails 6.1, no monkey patching is used.
   * `to_component_class` has been removed.

docs/guide/caching.md

@@ -0,0 +1,45 @@
+---
+layout: default
+title: Caching
+parent: How-to guide
+---
+
+# Caching
+
+Experimental
+{: .label }
+
+Caching is experimental.
+
+To enable caching, include `ViewComponent::ExperimentallyCacheable`.
+
+Components implement caching by marking dependencies using `cache_on`:
+
+```ruby
+class CacheComponent < ViewComponent::Base
+  include ViewComponent::ExperimentallyCacheable
+
+  cache_on :foo, :bar
+  attr_reader :foo, :bar
+
+  def initialize(foo:, bar:)
+    @foo = foo
+    @bar = bar
+  end
+end
+```
+
+```erb
+<p><%= view_cache_dependencies.inspect %></p>
+
+<p><%= Time.zone.now %></p>
+<p><%= "#{foo} #{bar}" %></p>
+```
+
+`cache_on` accepts method names. Returned values are expanded via `ActiveSupport::Cache.expand_cache_key`, so Active Record models, `GlobalID`, arrays, and plain strings work as expected.
+
+Methods listed in `cache_on` may be private.
+
+The cache key includes a digest of component source (Ruby + templates + i18n sidecars) and rendered child ViewComponents.
+
+Partial/layout string dependencies aren't currently included in the digest, to invalidate the cache on deploy modify `RAILS_CACHE_ID`/`RAILS_APP_VERSION`.

gemfiles/rails_7.1.gemfile.lock

@@ -3,6 +3,7 @@ PATH
   specs:
     view_component (4.4.0)
       actionview (>= 7.1.0)
+      actionview_precompiler (>= 0.4)
       activesupport (>= 7.1.0)
       concurrent-ruby (~> 1)
 
@@ -60,6 +61,8 @@ GEM
       erubi (~> 1.11)
       rails-dom-testing (~> 2.2)
       rails-html-sanitizer (~> 1.6)
+    actionview_precompiler (0.4.0)
+      actionview (>= 6.0.a)
     activejob (7.1.6)
       activesupport (= 7.1.6)
       globalid (>= 0.3.6)

gemfiles/rails_7.2.gemfile.lock

@@ -3,6 +3,7 @@ PATH
   specs:
     view_component (4.4.0)
       actionview (>= 7.1.0)
+      actionview_precompiler (>= 0.4)
       activesupport (>= 7.1.0)
       concurrent-ruby (~> 1)
 
@@ -55,6 +56,8 @@ GEM
       erubi (~> 1.11)
       rails-dom-testing (~> 2.2)
       rails-html-sanitizer (~> 1.6)
+    actionview_precompiler (0.4.0)
+      actionview (>= 6.0.a)
     activejob (7.2.3)
       activesupport (= 7.2.3)
       globalid (>= 0.3.6)

gemfiles/rails_8.0.gemfile.lock

@@ -3,6 +3,7 @@ PATH
   specs:
     view_component (4.4.0)
       actionview (>= 7.1.0)
+      actionview_precompiler (>= 0.4)
       activesupport (>= 7.1.0)
       concurrent-ruby (~> 1)
 
@@ -52,6 +53,8 @@ GEM
       erubi (~> 1.11)
       rails-dom-testing (~> 2.2)
       rails-html-sanitizer (~> 1.6)
+    actionview_precompiler (0.4.0)
+      actionview (>= 6.0.a)
     activejob (8.0.4)
       activesupport (= 8.0.4)
       globalid (>= 0.3.6)

gemfiles/rails_8.1.gemfile.lock

@@ -3,6 +3,7 @@ PATH
   specs:
     view_component (4.4.0)
       actionview (>= 7.1.0)
+      actionview_precompiler (>= 0.4)
       activesupport (>= 7.1.0)
       concurrent-ruby (~> 1)
 
@@ -55,6 +56,8 @@ GEM
       erubi (~> 1.11)
       rails-dom-testing (~> 2.2)
       rails-html-sanitizer (~> 1.6)
+    actionview_precompiler (0.4.0)
+      actionview (>= 6.0.a)
     activejob (8.1.2)
       activesupport (= 8.1.2)
       globalid (>= 0.3.6)