[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, 0 insertions, 259 deletions

diff --git a/internal/timeline/manager.go b/internal/timeline/manager.go
deleted file mode 100644
index b4f075138..000000000
--- a/internal/timeline/manager.go
+++ /dev/null
@@ -1,259 +0,0 @@
-// GoToSocial
-// Copyright (C) GoToSocial Authors admin@gotosocial.org
-// SPDX-License-Identifier: AGPL-3.0-or-later
-//
-// This program is free software: you can redistribute it and/or modify
-// it under the terms of the GNU Affero General Public License as published by
-// the Free Software Foundation, either version 3 of the License, or
-// (at your option) any later version.
-//
-// This program is distributed in the hope that it will be useful,
-// but WITHOUT ANY WARRANTY; without even the implied warranty of
-// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-// GNU Affero General Public License for more details.
-//
-// You should have received a copy of the GNU Affero General Public License
-// along with this program.  If not, see <http://www.gnu.org/licenses/>.
-
-package timeline
-
-import (
-	"context"
-	"sync"
-	"time"
-
-	"github.com/superseriousbusiness/gotosocial/internal/gtserror"
-	"github.com/superseriousbusiness/gotosocial/internal/log"
-)
-
-const (
-	pruneLengthIndexed  = 400
-	pruneLengthPrepared = 50
-)
-
-// Manager abstracts functions for creating multiple timelines, and adding, removing, and fetching entries from those timelines.
-//
-// By the time a timelineable hits the manager interface, it should already have been filtered and it should be established that the item indeed
-// belongs in the given timeline.
-//
-// The manager makes a distinction between *indexed* items and *prepared* items.
-//
-// Indexed items consist of just that item's ID (in the database) and the time it was created. An indexed item takes up very little memory, so
-// it's not a huge priority to keep trimming the indexed items list.
-//
-// Prepared items consist of the item's database ID, the time it was created, AND the apimodel representation of that item, for quick serialization.
-// Prepared items of course take up more memory than indexed items, so they should be regularly pruned if they're not being actively served.
-type Manager interface {
-	// IngestOne takes one timelineable and indexes it into the given timeline, and then immediately prepares it for serving.
-	// This is useful in cases where we know the item will need to be shown at the top of a user's timeline immediately (eg., a new status is created).
-	//
-	// It should already be established before calling this function that the item actually belongs in the timeline!
-	//
-	// The returned bool indicates whether the item was actually put in the timeline. This could be false in cases where
-	// a status is a boost, but a boost of the original status or the status itself already exists recently in the timeline.
-	IngestOne(ctx context.Context, timelineID string, item Timelineable) (bool, error)
-
-	// GetTimeline returns limit n amount of prepared entries from the given timeline, in descending chronological order.
-	GetTimeline(ctx context.Context, timelineID string, maxID string, sinceID string, minID string, limit int, local bool) ([]Preparable, error)
-
-	// GetIndexedLength returns the amount of items that have been indexed for the given account ID.
-	GetIndexedLength(ctx context.Context, timelineID string) int
-
-	// GetOldestIndexedID returns the id ID for the oldest item that we have indexed for the given timeline.
-	// Will be an empty string if nothing is (yet) indexed.
-	GetOldestIndexedID(ctx context.Context, timelineID string) string
-
-	// Remove removes one item from the given timeline.
-	Remove(ctx context.Context, timelineID string, itemID string) (int, error)
-
-	// RemoveTimeline completely removes one timeline.
-	RemoveTimeline(ctx context.Context, timelineID string) error
-
-	// WipeItemFromAllTimelines removes one item from the index and prepared items of all timelines
-	WipeItemFromAllTimelines(ctx context.Context, itemID string) error
-
-	// WipeStatusesFromAccountID removes all items by the given accountID from the given timeline.
-	WipeItemsFromAccountID(ctx context.Context, timelineID string, accountID string) error
-
-	// UnprepareItem unprepares/uncaches the prepared version fo the given itemID from the given timelineID.
-	// Use this for cache invalidation when the prepared representation of an item has changed.
-	UnprepareItem(ctx context.Context, timelineID string, itemID string) error
-
-	// UnprepareItemFromAllTimelines unprepares/uncaches the prepared version of the given itemID from all timelines.
-	// Use this for cache invalidation when the prepared representation of an item has changed.
-	UnprepareItemFromAllTimelines(ctx context.Context, itemID string) error
-
-	// Prune manually triggers a prune operation for the given timelineID.
-	Prune(ctx context.Context, timelineID string, desiredPreparedItemsLength int, desiredIndexedItemsLength int) (int, error)
-
-	// Start starts hourly cleanup jobs for this timeline manager.
-	Start() error
-
-	// Stop stops the timeline manager (currently a stub, doesn't do anything).
-	Stop() error
-}
-
-// NewManager returns a new timeline manager.
-func NewManager(grabFunction GrabFunction, filterFunction FilterFunction, prepareFunction PrepareFunction, skipInsertFunction SkipInsertFunction) Manager {
-	return &manager{
-		timelines:          sync.Map{},
-		grabFunction:       grabFunction,
-		filterFunction:     filterFunction,
-		prepareFunction:    prepareFunction,
-		skipInsertFunction: skipInsertFunction,
-	}
-}
-
-type manager struct {
-	timelines          sync.Map
-	grabFunction       GrabFunction
-	filterFunction     FilterFunction
-	prepareFunction    PrepareFunction
-	skipInsertFunction SkipInsertFunction
-}
-
-func (m *manager) Start() error {
-	// Start a background goroutine which iterates
-	// through all stored timelines once per hour,
-	// and cleans up old entries if that timeline
-	// hasn't been accessed in the last hour.
-	go func() {
-		for now := range time.NewTicker(1 * time.Hour).C {
-			now := now // rescope
-			// Define the range function inside here,
-			// so that we can use the 'now' returned
-			// by the ticker, instead of having to call
-			// time.Now() multiple times.
-			//
-			// Unless it panics, this function always
-			// returns 'true', to continue the Range
-			// call through the sync.Map.
-			f := func(_ any, v any) bool {
-				timeline, ok := v.(Timeline)
-				if !ok {
-					log.Panic(nil, "couldn't parse timeline manager sync map value as Timeline, this should never happen so panic")
-				}
-
-				if now.Sub(timeline.LastGot()) < 1*time.Hour {
-					// Timeline has been fetched in the
-					// last hour, move on to the next one.
-					return true
-				}
-
-				if amountPruned := timeline.Prune(pruneLengthPrepared, pruneLengthIndexed); amountPruned > 0 {
-					log.WithField("accountID", timeline.TimelineID()).Infof("pruned %d indexed and prepared items from timeline", amountPruned)
-				}
-
-				return true
-			}
-
-			// Execute the function for each timeline.
-			m.timelines.Range(f)
-		}
-	}()
-
-	return nil
-}
-
-func (m *manager) Stop() error {
-	return nil
-}
-
-func (m *manager) IngestOne(ctx context.Context, timelineID string, item Timelineable) (bool, error) {
-	return m.getOrCreateTimeline(ctx, timelineID).IndexAndPrepareOne(
-		ctx,
-		item.GetID(),
-		item.GetBoostOfID(),
-		item.GetAccountID(),
-		item.GetBoostOfAccountID(),
-	)
-}
-
-func (m *manager) Remove(ctx context.Context, timelineID string, itemID string) (int, error) {
-	return m.getOrCreateTimeline(ctx, timelineID).Remove(ctx, itemID)
-}
-
-func (m *manager) RemoveTimeline(ctx context.Context, timelineID string) error {
-	m.timelines.Delete(timelineID)
-	return nil
-}
-
-func (m *manager) GetTimeline(ctx context.Context, timelineID string, maxID string, sinceID string, minID string, limit int, local bool) ([]Preparable, error) {
-	return m.getOrCreateTimeline(ctx, timelineID).Get(ctx, limit, maxID, sinceID, minID, true)
-}
-
-func (m *manager) GetIndexedLength(ctx context.Context, timelineID string) int {
-	return m.getOrCreateTimeline(ctx, timelineID).Len()
-}
-
-func (m *manager) GetOldestIndexedID(ctx context.Context, timelineID string) string {
-	return m.getOrCreateTimeline(ctx, timelineID).OldestIndexedItemID()
-}
-
-func (m *manager) WipeItemFromAllTimelines(ctx context.Context, itemID string) error {
-	errs := new(gtserror.MultiError)
-
-	m.timelines.Range(func(_ any, v any) bool {
-		if _, err := v.(Timeline).Remove(ctx, itemID); err != nil {
-			errs.Append(err)
-		}
-
-		return true // always continue range
-	})
-
-	if err := errs.Combine(); err != nil {
-		return gtserror.Newf("error(s) wiping status %s: %w", itemID, errs.Combine())
-	}
-
-	return nil
-}
-
-func (m *manager) WipeItemsFromAccountID(ctx context.Context, timelineID string, accountID string) error {
-	_, err := m.getOrCreateTimeline(ctx, timelineID).RemoveAllByOrBoosting(ctx, accountID)
-	return err
-}
-
-func (m *manager) UnprepareItemFromAllTimelines(ctx context.Context, itemID string) error {
-	errs := new(gtserror.MultiError)
-
-	// Work through all timelines held by this
-	// manager, and call Unprepare for each.
-	m.timelines.Range(func(_ any, v any) bool {
-		if err := v.(Timeline).Unprepare(ctx, itemID); err != nil {
-			errs.Append(err)
-		}
-
-		return true // always continue range
-	})
-
-	if err := errs.Combine(); err != nil {
-		return gtserror.Newf("error(s) unpreparing status %s: %w", itemID, errs.Combine())
-	}
-
-	return nil
-}
-
-func (m *manager) UnprepareItem(ctx context.Context, timelineID string, itemID string) error {
-	return m.getOrCreateTimeline(ctx, timelineID).Unprepare(ctx, itemID)
-}
-
-func (m *manager) Prune(ctx context.Context, timelineID string, desiredPreparedItemsLength int, desiredIndexedItemsLength int) (int, error) {
-	return m.getOrCreateTimeline(ctx, timelineID).Prune(desiredPreparedItemsLength, desiredIndexedItemsLength), nil
-}
-
-// getOrCreateTimeline returns a timeline with the given id,
-// creating a new timeline with that id if necessary.
-func (m *manager) getOrCreateTimeline(ctx context.Context, timelineID string) Timeline {
-	i, ok := m.timelines.Load(timelineID)
-	if ok {
-		// Timeline already existed in sync.Map.
-		return i.(Timeline)
-	}
-
-	// Timeline did not yet exist in sync.Map.
-	// Create + store it.
-	timeline := NewTimeline(ctx, timelineID, m.grabFunction, m.filterFunction, m.prepareFunction, m.skipInsertFunction)
-	m.timelines.Store(timelineID, timeline)
-
-	return timeline
-}