gotosocial/internal/timeline/get.go
Tobi Smethurst 16e486ad96
Timeline bugfix (#60)
* fix a stack overflow in the timeline

* go fmt
2021-06-23 18:42:20 +02:00

315 lines
9 KiB
Go

package timeline
import (
"container/list"
"errors"
"fmt"
"github.com/sirupsen/logrus"
apimodel "github.com/superseriousbusiness/gotosocial/internal/api/model"
)
func (t *timeline) Get(amount int, maxID string, sinceID string, minID string) ([]*apimodel.Status, error) {
l := t.log.WithFields(logrus.Fields{
"func": "Get",
"accountID": t.accountID,
"amount": amount,
"maxID": maxID,
"sinceID": sinceID,
"minID": minID,
})
l.Debug("entering get")
var statuses []*apimodel.Status
var err error
// no params are defined to just fetch from the top
if maxID == "" && sinceID == "" && minID == "" {
statuses, err = t.GetXFromTop(amount)
// aysnchronously prepare the next predicted query so it's ready when the user asks for it
if len(statuses) != 0 {
nextMaxID := statuses[len(statuses)-1].ID
go func() {
if err := t.prepareNextQuery(amount, nextMaxID, "", ""); err != nil {
l.Errorf("error preparing next query: %s", err)
}
}()
}
}
// maxID is defined but sinceID isn't so take from behind
if maxID != "" && sinceID == "" {
statuses, err = t.GetXBehindID(amount, maxID)
// aysnchronously prepare the next predicted query so it's ready when the user asks for it
if len(statuses) != 0 {
nextMaxID := statuses[len(statuses)-1].ID
go func() {
if err := t.prepareNextQuery(amount, nextMaxID, "", ""); err != nil {
l.Errorf("error preparing next query: %s", err)
}
}()
}
}
// maxID is defined and sinceID || minID are as well, so take a slice between them
if maxID != "" && sinceID != "" {
statuses, err = t.GetXBetweenID(amount, maxID, minID)
}
if maxID != "" && minID != "" {
statuses, err = t.GetXBetweenID(amount, maxID, minID)
}
// maxID isn't defined, but sinceID || minID are, so take x before
if maxID == "" && sinceID != "" {
statuses, err = t.GetXBeforeID(amount, sinceID, true)
}
if maxID == "" && minID != "" {
statuses, err = t.GetXBeforeID(amount, minID, true)
}
return statuses, err
}
func (t *timeline) GetXFromTop(amount int) ([]*apimodel.Status, error) {
// make a slice of statuses with the length we need to return
statuses := make([]*apimodel.Status, 0, amount)
if t.preparedPosts.data == nil {
t.preparedPosts.data = &list.List{}
}
// make sure we have enough posts prepared to return
if t.preparedPosts.data.Len() < amount {
if err := t.PrepareFromTop(amount); err != nil {
return nil, err
}
}
// work through the prepared posts from the top and return
var served int
for e := t.preparedPosts.data.Front(); e != nil; e = e.Next() {
entry, ok := e.Value.(*preparedPostsEntry)
if !ok {
return nil, errors.New("GetXFromTop: could not parse e as a preparedPostsEntry")
}
statuses = append(statuses, entry.prepared)
served = served + 1
if served >= amount {
break
}
}
return statuses, nil
}
func (t *timeline) GetXBehindID(amount int, behindID string) ([]*apimodel.Status, error) {
// make a slice of statuses with the length we need to return
statuses := make([]*apimodel.Status, 0, amount)
if t.preparedPosts.data == nil {
t.preparedPosts.data = &list.List{}
}
// iterate through the modified list until we hit the mark we're looking for
var position int
var behindIDMark *list.Element
findMarkLoop:
for e := t.preparedPosts.data.Front(); e != nil; e = e.Next() {
position = position + 1
entry, ok := e.Value.(*preparedPostsEntry)
if !ok {
return nil, errors.New("GetXBehindID: could not parse e as a preparedPostsEntry")
}
if entry.statusID == behindID {
behindIDMark = e
break findMarkLoop
}
}
// we didn't find it, so we need to make sure it's indexed and prepared and then try again
if behindIDMark == nil {
if err := t.IndexBehind(behindID, amount); err != nil {
return nil, fmt.Errorf("GetXBehindID: error indexing behind and including ID %s", behindID)
}
if err := t.PrepareBehind(behindID, amount); err != nil {
return nil, fmt.Errorf("GetXBehindID: error preparing behind and including ID %s", behindID)
}
oldestID, err := t.OldestPreparedPostID()
if err != nil {
return nil, err
}
if oldestID == "" || oldestID == behindID {
// there is no oldest prepared post, or the oldest prepared post is still the post we're looking for entries after
// this means we should just return the empty statuses slice since we don't have any more posts to offer
return statuses, nil
}
return t.GetXBehindID(amount, behindID)
}
// make sure we have enough posts prepared behind it to return what we're being asked for
if t.preparedPosts.data.Len() < amount+position {
if err := t.PrepareBehind(behindID, amount); err != nil {
return nil, err
}
}
// start serving from the entry right after the mark
var served int
serveloop:
for e := behindIDMark.Next(); e != nil; e = e.Next() {
entry, ok := e.Value.(*preparedPostsEntry)
if !ok {
return nil, errors.New("GetXBehindID: could not parse e as a preparedPostsEntry")
}
// serve up to the amount requested
statuses = append(statuses, entry.prepared)
served = served + 1
if served >= amount {
break serveloop
}
}
return statuses, nil
}
func (t *timeline) GetXBeforeID(amount int, beforeID string, startFromTop bool) ([]*apimodel.Status, error) {
// make a slice of statuses with the length we need to return
statuses := make([]*apimodel.Status, 0, amount)
if t.preparedPosts.data == nil {
t.preparedPosts.data = &list.List{}
}
// iterate through the modified list until we hit the mark we're looking for
var beforeIDMark *list.Element
findMarkLoop:
for e := t.preparedPosts.data.Front(); e != nil; e = e.Next() {
entry, ok := e.Value.(*preparedPostsEntry)
if !ok {
return nil, errors.New("GetXBeforeID: could not parse e as a preparedPostsEntry")
}
if entry.statusID == beforeID {
beforeIDMark = e
break findMarkLoop
}
}
// we didn't find it, so we need to make sure it's indexed and prepared and then try again
if beforeIDMark == nil {
if err := t.IndexBefore(beforeID, true, amount); err != nil {
return nil, fmt.Errorf("GetXBeforeID: error indexing before and including ID %s", beforeID)
}
if err := t.PrepareBefore(beforeID, true, amount); err != nil {
return nil, fmt.Errorf("GetXBeforeID: error preparing before and including ID %s", beforeID)
}
return t.GetXBeforeID(amount, beforeID, startFromTop)
}
var served int
if startFromTop {
// start serving from the front/top and keep going until we hit mark or get x amount statuses
serveloopFromTop:
for e := t.preparedPosts.data.Front(); e != nil; e = e.Next() {
entry, ok := e.Value.(*preparedPostsEntry)
if !ok {
return nil, errors.New("GetXBeforeID: could not parse e as a preparedPostsEntry")
}
if entry.statusID == beforeID {
break serveloopFromTop
}
// serve up to the amount requested
statuses = append(statuses, entry.prepared)
served = served + 1
if served >= amount {
break serveloopFromTop
}
}
} else if !startFromTop {
// start serving from the entry right before the mark
serveloopFromBottom:
for e := beforeIDMark.Prev(); e != nil; e = e.Prev() {
entry, ok := e.Value.(*preparedPostsEntry)
if !ok {
return nil, errors.New("GetXBeforeID: could not parse e as a preparedPostsEntry")
}
// serve up to the amount requested
statuses = append(statuses, entry.prepared)
served = served + 1
if served >= amount {
break serveloopFromBottom
}
}
}
return statuses, nil
}
func (t *timeline) GetXBetweenID(amount int, behindID string, beforeID string) ([]*apimodel.Status, error) {
// make a slice of statuses with the length we need to return
statuses := make([]*apimodel.Status, 0, amount)
if t.preparedPosts.data == nil {
t.preparedPosts.data = &list.List{}
}
// iterate through the modified list until we hit the mark we're looking for
var position int
var behindIDMark *list.Element
findMarkLoop:
for e := t.preparedPosts.data.Front(); e != nil; e = e.Next() {
position = position + 1
entry, ok := e.Value.(*preparedPostsEntry)
if !ok {
return nil, errors.New("GetXBetweenID: could not parse e as a preparedPostsEntry")
}
if entry.statusID == behindID {
behindIDMark = e
break findMarkLoop
}
}
// we didn't find it
if behindIDMark == nil {
return nil, fmt.Errorf("GetXBetweenID: couldn't find status with ID %s", behindID)
}
// make sure we have enough posts prepared behind it to return what we're being asked for
if t.preparedPosts.data.Len() < amount+position {
if err := t.PrepareBehind(behindID, amount); err != nil {
return nil, err
}
}
// start serving from the entry right after the mark
var served int
serveloop:
for e := behindIDMark.Next(); e != nil; e = e.Next() {
entry, ok := e.Value.(*preparedPostsEntry)
if !ok {
return nil, errors.New("GetXBetweenID: could not parse e as a preparedPostsEntry")
}
if entry.statusID == beforeID {
break serveloop
}
// serve up to the amount requested
statuses = append(statuses, entry.prepared)
served = served + 1
if served >= amount {
break serveloop
}
}
return statuses, nil
}