[performance] refactoring + add fave / follow / request / visibility caching (#1607)

* refactor visibility checking, add caching for visibility

* invalidate visibility cache items on account / status deletes

* fix requester ID passed to visibility cache nil ptr

* de-interface caches, fix home / public timeline caching + visibility

* finish adding code comments for visibility filter

* fix angry goconst linter warnings

* actually finish adding filter visibility code comments for timeline functions

* move home timeline status author check to after visibility

* remove now-unused code

* add more code comments

* add TODO code comment, update printed cache start names

* update printed cache names on stop

* start adding separate follow(request) delete db functions, add specific visibility cache tests

* add relationship type caching

* fix getting local account follows / followed-bys, other small codebase improvements

* simplify invalidation using cache hooks, add more GetAccountBy___() functions

* fix boosting to return 404 if not boostable but no error (to not leak status ID)

* remove dead code

* improved placement of cache invalidation

* update license headers

* add example follow, follow-request config entries

* add example visibility cache configuration to config file

* use specific PutFollowRequest() instead of just Put()

* add tests for all GetAccountBy()

* add GetBlockBy() tests

* update block to check primitive fields

* update and finish adding Get{Account,Block,Follow,FollowRequest}By() tests

* fix copy-pasted code

* update envparsing test

* whitespace

* fix bun struct tag

* add license header to gtscontext

* fix old license header

* improved error creation to not use fmt.Errorf() when not needed

* fix various rebase conflicts, fix account test

* remove commented-out code, fix-up mention caching

* fix mention select bun statement

* ensure mention target account populated, pass in context to customrenderer logging

* remove more uncommented code, fix typeutil test

* add statusfave database model caching

* add status fave cache configuration

* add status fave cache example config

* woops, catch missed error. nice catch linter!

* add back testrig panic on nil db

* update example configuration to match defaults, slight tweak to cache configuration defaults

* update envparsing test with new defaults

* fetch followingget to use the follow target account

* use accounnt.IsLocal() instead of empty domain check

* use constants for the cache visibility type check

* use bun.In() for notification type restriction in db query

* include replies when fetching PublicTimeline() (to account for single-author threads in Visibility{}.StatusPublicTimelineable())

* use bun query building for nested select statements to ensure working with postgres

* update public timeline future status checks to match visibility filter

* same as previous, for home timeline

* update public timeline tests to dynamically check for appropriate statuses

* migrate accounts to allow unique constraint on public_key

* provide minimal account with publicKey

---------

Signed-off-by: kim <grufwub@gmail.com>
Co-authored-by: tsmethurst <tobi.smethurst@protonmail.com>

internal/cache/cache.go

@@ -17,13 +17,23 @@
 
 package cache
 
+import (
+	"github.com/superseriousbusiness/gotosocial/internal/gtsmodel"
+)
+
 type Caches struct {
 	// GTS provides access to the collection of gtsmodel object caches.
+	// (used by the database).
 	GTS GTSCaches
 
 	// AP provides access to the collection of ActivityPub object caches.
+	// (planned to be used by the typeconverter).
 	AP APCaches
 
+	// Visibility provides access to the item visibility cache.
+	// (used by the visibility filter).
+	Visibility VisibilityCache
+
 	// prevent pass-by-value.
 	_ nocopy
 }
@@ -31,29 +41,77 @@ type Caches struct {
 // Init will (re)initialize both the GTS and AP cache collections.
 // NOTE: the cache MUST NOT be in use anywhere, this is not thread-safe.
 func (c *Caches) Init() {
-	if c.GTS == nil {
-		// use default impl
-		c.GTS = NewGTS()
-	}
-
-	if c.AP == nil {
-		// use default impl
-		c.AP = NewAP()
-	}
-
-	// initialize caches
 	c.GTS.Init()
 	c.AP.Init()
+	c.Visibility.Init()
+
+	// Setup cache invalidate hooks.
+	// !! READ THE METHOD COMMENT
+	c.setuphooks()
 }
 
 // Start will start both the GTS and AP cache collections.
 func (c *Caches) Start() {
 	c.GTS.Start()
 	c.AP.Start()
+	c.Visibility.Start()
 }
 
 // Stop will stop both the GTS and AP cache collections.
 func (c *Caches) Stop() {
 	c.GTS.Stop()
 	c.AP.Stop()
+	c.Visibility.Stop()
+}
+
+// setuphooks sets necessary cache invalidation hooks between caches,
+// as an invalidation indicates a database UPDATE / DELETE. INSERT is
+// not handled by invalidation hooks and must be invalidated manually.
+func (c *Caches) setuphooks() {
+	c.GTS.Account().SetInvalidateCallback(func(account *gtsmodel.Account) {
+		// Invalidate account ID cached visibility.
+		c.Visibility.Invalidate("ItemID", account.ID)
+		c.Visibility.Invalidate("RequesterID", account.ID)
+	})
+
+	c.GTS.Block().SetInvalidateCallback(func(block *gtsmodel.Block) {
+		// Invalidate block origin account ID cached visibility.
+		c.Visibility.Invalidate("ItemID", block.AccountID)
+		c.Visibility.Invalidate("RequesterID", block.AccountID)
+
+		// Invalidate block target account ID cached visibility.
+		c.Visibility.Invalidate("ItemID", block.TargetAccountID)
+		c.Visibility.Invalidate("RequesterID", block.TargetAccountID)
+	})
+
+	c.GTS.Follow().SetInvalidateCallback(func(follow *gtsmodel.Follow) {
+		// Invalidate follow origin account ID cached visibility.
+		c.Visibility.Invalidate("ItemID", follow.AccountID)
+		c.Visibility.Invalidate("RequesterID", follow.AccountID)
+
+		// Invalidate follow target account ID cached visibility.
+		c.Visibility.Invalidate("ItemID", follow.TargetAccountID)
+		c.Visibility.Invalidate("RequesterID", follow.TargetAccountID)
+	})
+
+	c.GTS.FollowRequest().SetInvalidateCallback(func(followReq *gtsmodel.FollowRequest) {
+		// Invalidate follow request origin account ID cached visibility.
+		c.Visibility.Invalidate("ItemID", followReq.AccountID)
+		c.Visibility.Invalidate("RequesterID", followReq.AccountID)
+
+		// Invalidate follow request target account ID cached visibility.
+		c.Visibility.Invalidate("ItemID", followReq.TargetAccountID)
+		c.Visibility.Invalidate("RequesterID", followReq.TargetAccountID)
+	})
+
+	c.GTS.Status().SetInvalidateCallback(func(status *gtsmodel.Status) {
+		// Invalidate status ID cached visibility.
+		c.Visibility.Invalidate("ItemID", status.ID)
+	})
+
+	c.GTS.User().SetInvalidateCallback(func(user *gtsmodel.User) {
+		// Invalidate local account ID cached visibility.
+		c.Visibility.Invalidate("ItemID", user.AccountID)
+		c.Visibility.Invalidate("RequesterID", user.AccountID)
+	})
 }