gotosocial/internal/timeline/prepare.go

264 lines
7.5 KiB
Go

/*
GoToSocial
Copyright (C) 2021-2023 GoToSocial Authors admin@gotosocial.org
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 (
"container/list"
"context"
"errors"
"fmt"
"codeberg.org/gruf/go-kv"
"github.com/superseriousbusiness/gotosocial/internal/db"
"github.com/superseriousbusiness/gotosocial/internal/id"
"github.com/superseriousbusiness/gotosocial/internal/log"
)
func (t *timeline) PrepareFromTop(ctx context.Context, amount int) error {
l := log.WithFields(kv.Fields{{"amount", amount}}...)
// lazily initialize prepared posts if it hasn't been done already
if t.preparedItems.data == nil {
t.preparedItems.data = &list.List{}
t.preparedItems.data.Init()
}
// if the postindex is nil, nothing has been indexed yet so index from the highest ID possible
if t.indexedItems.data == nil {
l.Debug("postindex.data was nil, indexing behind highest possible ID")
if err := t.indexBehind(ctx, id.Highest, amount); err != nil {
return fmt.Errorf("PrepareFromTop: error indexing behind id %s: %s", id.Highest, err)
}
}
l.Trace("entering prepareloop")
t.Lock()
defer t.Unlock()
var prepared int
prepareloop:
for e := t.indexedItems.data.Front(); e != nil; e = e.Next() {
if e == nil {
continue
}
entry, ok := e.Value.(*indexedItemsEntry)
if !ok {
return errors.New("PrepareFromTop: could not parse e as a postIndexEntry")
}
if err := t.prepare(ctx, entry.itemID); err != nil {
// there's been an error
if err != db.ErrNoEntries {
// it's a real error
return fmt.Errorf("PrepareFromTop: error preparing status with id %s: %s", entry.itemID, err)
}
// the status just doesn't exist (anymore) so continue to the next one
continue
}
prepared++
if prepared == amount {
// we're done
l.Trace("leaving prepareloop")
break prepareloop
}
}
l.Trace("leaving function")
return nil
}
func (t *timeline) prepareNextQuery(ctx context.Context, amount int, maxID string, sinceID string, minID string) error {
l := log.WithFields(kv.Fields{
{"amount", amount},
{"maxID", maxID},
{"sinceID", sinceID},
{"minID", minID},
}...)
var err error
switch {
case maxID != "" && sinceID == "":
l.Debug("preparing behind maxID")
err = t.prepareBehind(ctx, maxID, amount)
case maxID == "" && sinceID != "":
l.Debug("preparing before sinceID")
err = t.prepareBefore(ctx, sinceID, false, amount)
case maxID == "" && minID != "":
l.Debug("preparing before minID")
err = t.prepareBefore(ctx, minID, false, amount)
}
return err
}
// prepareBehind instructs the timeline to prepare the next amount of entries for serialization, from position onwards.
// If include is true, then the given item ID will also be prepared, otherwise only entries behind it will be prepared.
func (t *timeline) prepareBehind(ctx context.Context, itemID string, amount int) error {
// lazily initialize prepared items if it hasn't been done already
if t.preparedItems.data == nil {
t.preparedItems.data = &list.List{}
t.preparedItems.data.Init()
}
if err := t.indexBehind(ctx, itemID, amount); err != nil {
return fmt.Errorf("prepareBehind: error indexing behind id %s: %s", itemID, err)
}
// if the itemindex is nil, nothing has been indexed yet so there's nothing to prepare
if t.indexedItems.data == nil {
return nil
}
var prepared int
var preparing bool
t.Lock()
defer t.Unlock()
prepareloop:
for e := t.indexedItems.data.Front(); e != nil; e = e.Next() {
entry, ok := e.Value.(*indexedItemsEntry)
if !ok {
return errors.New("prepareBehind: could not parse e as itemIndexEntry")
}
if !preparing {
// we haven't hit the position we need to prepare from yet
if entry.itemID == itemID {
preparing = true
}
}
if preparing {
if err := t.prepare(ctx, entry.itemID); err != nil {
// there's been an error
if err != db.ErrNoEntries {
// it's a real error
return fmt.Errorf("prepareBehind: error preparing item with id %s: %s", entry.itemID, err)
}
// the status just doesn't exist (anymore) so continue to the next one
continue
}
if prepared == amount {
// we're done
break prepareloop
}
prepared++
}
}
return nil
}
func (t *timeline) prepareBefore(ctx context.Context, statusID string, include bool, amount int) error {
t.Lock()
defer t.Unlock()
// lazily initialize prepared posts if it hasn't been done already
if t.preparedItems.data == nil {
t.preparedItems.data = &list.List{}
t.preparedItems.data.Init()
}
// if the postindex is nil, nothing has been indexed yet so there's nothing to prepare
if t.indexedItems.data == nil {
return nil
}
var prepared int
var preparing bool
prepareloop:
for e := t.indexedItems.data.Back(); e != nil; e = e.Prev() {
entry, ok := e.Value.(*indexedItemsEntry)
if !ok {
return errors.New("prepareBefore: could not parse e as a postIndexEntry")
}
if !preparing {
// we haven't hit the position we need to prepare from yet
if entry.itemID == statusID {
preparing = true
if !include {
continue
}
}
}
if preparing {
if err := t.prepare(ctx, entry.itemID); err != nil {
// there's been an error
if err != db.ErrNoEntries {
// it's a real error
return fmt.Errorf("prepareBefore: error preparing status with id %s: %s", entry.itemID, err)
}
// the status just doesn't exist (anymore) so continue to the next one
continue
}
if prepared == amount {
// we're done
break prepareloop
}
prepared++
}
}
return nil
}
func (t *timeline) prepare(ctx context.Context, itemID string) error {
// trigger the caller-provided prepare function
prepared, err := t.prepareFunction(ctx, t.accountID, itemID)
if err != nil {
return err
}
// shove it in prepared items as a prepared items entry
preparedItemsEntry := &preparedItemsEntry{
itemID: prepared.GetID(),
boostOfID: prepared.GetBoostOfID(),
accountID: prepared.GetAccountID(),
boostOfAccountID: prepared.GetBoostOfAccountID(),
prepared: prepared,
}
return t.preparedItems.insertPrepared(ctx, preparedItemsEntry)
}
// oldestPreparedItemID returns the id of the rearmost (ie., the oldest) prepared item, or an error if something goes wrong.
// If nothing goes wrong but there's no oldest item, an empty string will be returned so make sure to check for this.
func (t *timeline) oldestPreparedItemID(ctx context.Context) (string, error) {
var id string
if t.preparedItems == nil || t.preparedItems.data == nil {
// return an empty string if prepared items hasn't been initialized yet
return id, nil
}
e := t.preparedItems.data.Back()
if e == nil {
// return an empty string if there's no back entry (ie., the index list hasn't been initialized yet)
return id, nil
}
entry, ok := e.Value.(*preparedItemsEntry)
if !ok {
return id, errors.New("oldestPreparedItemID: could not parse e as a preparedItemsEntry")
}
return entry.itemID, nil
}