[performance] rewrite timelines to rely on new timeline cache type (#3941)

* start work rewriting timeline cache type

* further work rewriting timeline caching

* more work integration new timeline code

* remove old code

* add local timeline, fix up merge conflicts

* remove old use of go-bytes

* implement new timeline code into more areas of codebase, pull in latest go-mangler, go-mutexes, go-structr

* remove old timeline package, add local timeline cache

* remove references to old timeline types that needed starting up in tests

* start adding page validation

* fix test-identified timeline cache package issues

* fix up more tests, fix missing required changes, etc

* add exclusion for test.out in gitignore

* clarify some things better in code comments

* tweak cache size limits

* fix list timeline cache fetching

* further list timeline fixes

* linter, ssssssssshhhhhhhhhhhh please

* fix linter hints

* reslice the output if it's beyond length of 'lim'

* remove old timeline initialization code, bump go-structr to v0.9.4

* continued from previous commit

* improved code comments

* don't allow multiple entries for BoostOfID values to prevent repeated boosts of same boosts

* finish writing more code comments

* some variable renaming, for ease of following

* change the way we update lo,hi paging values during timeline load

* improved code comments for updated / returned lo , hi paging values

* finish writing code comments for the StatusTimeline{} type itself

* fill in more code comments

* update go-structr version to latest with changed timeline unique indexing logic

* have a local and public timeline *per user*

* rewrite calls to public / local timeline calls

* remove the zero length check, as lo, hi values might still be set

* simplify timeline cache loading, fix lo/hi returns, fix timeline invalidation side-effects missing for some federated actions

* swap the lo, hi values :facepalm:

* add (now) missing slice reverse of tag timeline statuses when paging ASC

* remove local / public caches (is out of scope for this work), share more timeline code

* remove unnecessary change

* again, remove more unused code

* remove unused function to appease the linter

* move boost checking to prepare function

* fix use of timeline.lastOrder, fix incorrect range functions used

* remove comments for repeat code

* remove the boost logic from prepare function

* do a maximum of 5 loads, not 10

* add repeat boost filtering logic, update go-structr, general improvements

* more code comments

* add important note

* fix timeline tests now that timelines are returned in page order

* remove unused field

* add StatusTimeline{} tests

* add more status timeline tests

* start adding preloading support

* ensure repeat boosts are marked in preloaded entries

* share a bunch of the database load code in timeline cache, don't clear timelines on relationship change

* add logic to allow dynamic clear / preloading of timelines

* comment-out unused functions, but leave in place as we might end-up using them

* fix timeline preload state check

* much improved status timeline code comments

* more code comments, don't bother inserting statuses if timeline not preloaded

* shift around some logic to make sure things aren't accidentally left set

* finish writing code comments

* remove trim-after-insert behaviour

* fix-up some comments referring to old logic

* remove unsetting of lo, hi

* fix preload repeatBoost checking logic

* don't return on status filter errors, these are usually transient

* better concurrency safety in Clear() and Done()

* fix test broken due to addition of preloader

* fix repeatBoost logic that doesn't account for already-hidden repeatBoosts

* ensure edit submodels are dropped on cache insertion

* update code-comment to expand CAS accronym

* use a plus1hULID() instead of 24h

* remove unused functions

* add note that public / local timeline requester can be nil

* fix incorrect visibility filtering of tag timeline statuses

* ensure we filter home timeline statuses on local only

* some small re-orderings to confirm query params in correct places

* fix the local only home timeline filter func

1 files changed, 35 insertions, 9 deletions

diff --git a/vendor/codeberg.org/gruf/go-structr/timeline.go b/vendor/codeberg.org/gruf/go-structr/timeline.go
index 0eb1e3aa5..0014e69ee 100644
--- a/vendor/codeberg.org/gruf/go-structr/timeline.go
+++ b/vendor/codeberg.org/gruf/go-structr/timeline.go
@@ -190,7 +190,8 @@ func (t *Timeline[T, PK]) Select(min, max *PK, length *int, dir Direction) (valu
 
 // Insert will insert the given values into the timeline,
 // calling any set invalidate hook on each inserted value.
-func (t *Timeline[T, PK]) Insert(values ...T) {
+// Returns current list length after performing inserts.
+func (t *Timeline[T, PK]) Insert(values ...T) int {
 
 	// Acquire lock.
 	t.mutex.Lock()
@@ -269,6 +270,10 @@ func (t *Timeline[T, PK]) Insert(values ...T) {
 	// Get func ptrs.
 	invalid := t.invalid
 
+	// Get length AFTER
+	// insert to return.
+	len := t.list.len
+
 	// Done with lock.
 	t.mutex.Unlock()
 
@@ -279,6 +284,8 @@ func (t *Timeline[T, PK]) Insert(values ...T) {
 			invalid(value)
 		}
 	}
+
+	return len
 }
 
 // Invalidate invalidates all entries stored in index under given keys.
@@ -336,8 +343,8 @@ func (t *Timeline[T, PK]) Invalidate(index *Index, keys ...Key) {
 //
 // Please note that the entire Timeline{} will be locked for the duration of the range
 // operation, i.e. from the beginning of the first yield call until the end of the last.
-func (t *Timeline[T, PK]) Range(dir Direction) func(yield func(T) bool) {
-	return func(yield func(T) bool) {
+func (t *Timeline[T, PK]) Range(dir Direction) func(yield func(index int, value T) bool) {
+	return func(yield func(int, T) bool) {
 		if t.copy == nil {
 			panic("not initialized")
 		} else if yield == nil {
@@ -348,7 +355,9 @@ func (t *Timeline[T, PK]) Range(dir Direction) func(yield func(T) bool) {
 		t.mutex.Lock()
 		defer t.mutex.Unlock()
 
+		var i int
 		switch dir {
+
 		case Asc:
 			// Iterate through linked list from bottom (i.e. tail).
 			for prev := t.list.tail; prev != nil; prev = prev.prev {
@@ -360,9 +369,12 @@ func (t *Timeline[T, PK]) Range(dir Direction) func(yield func(T) bool) {
 				value := t.copy(item.data.(T))
 
 				// Pass to given function.
-				if !yield(value) {
+				if !yield(i, value) {
 					break
 				}
+
+				// Iter
+				i++
 			}
 
 		case Desc:
@@ -376,9 +388,12 @@ func (t *Timeline[T, PK]) Range(dir Direction) func(yield func(T) bool) {
 				value := t.copy(item.data.(T))
 
 				// Pass to given function.
-				if !yield(value) {
+				if !yield(i, value) {
 					break
 				}
+
+				// Iter
+				i++
 			}
 		}
 	}
@@ -390,8 +405,8 @@ func (t *Timeline[T, PK]) Range(dir Direction) func(yield func(T) bool) {
 //
 // Please note that the entire Timeline{} will be locked for the duration of the range
 // operation, i.e. from the beginning of the first yield call until the end of the last.
-func (t *Timeline[T, PK]) RangeUnsafe(dir Direction) func(yield func(T) bool) {
-	return func(yield func(T) bool) {
+func (t *Timeline[T, PK]) RangeUnsafe(dir Direction) func(yield func(index int, value T) bool) {
+	return func(yield func(int, T) bool) {
 		if t.copy == nil {
 			panic("not initialized")
 		} else if yield == nil {
@@ -402,7 +417,9 @@ func (t *Timeline[T, PK]) RangeUnsafe(dir Direction) func(yield func(T) bool) {
 		t.mutex.Lock()
 		defer t.mutex.Unlock()
 
+		var i int
 		switch dir {
+
 		case Asc:
 			// Iterate through linked list from bottom (i.e. tail).
 			for prev := t.list.tail; prev != nil; prev = prev.prev {
@@ -411,9 +428,12 @@ func (t *Timeline[T, PK]) RangeUnsafe(dir Direction) func(yield func(T) bool) {
 				item := (*timeline_item)(prev.data)
 
 				// Pass to given function.
-				if !yield(item.data.(T)) {
+				if !yield(i, item.data.(T)) {
 					break
 				}
+
+				// Iter
+				i++
 			}
 
 		case Desc:
@@ -424,9 +444,12 @@ func (t *Timeline[T, PK]) RangeUnsafe(dir Direction) func(yield func(T) bool) {
 				item := (*timeline_item)(next.data)
 
 				// Pass to given function.
-				if !yield(item.data.(T)) {
+				if !yield(i, item.data.(T)) {
 					break
 				}
+
+				// Iter
+				i++
 			}
 		}
 	}
@@ -1033,6 +1056,9 @@ indexing:
 		// checking for collisions.
 		if !idx.add(key, i_item) {
 
+			// This key already appears
+			// in this unique index. So
+			// drop new timeline item.
 			t.delete(t_item)
 			free_buffer(buf)
 			return last