prevent linking fragment to itself when filling a gap

this seems to happen when at the beginning of the timeline and
make the timeline reader go into an infinite loop
This commit is contained in:
Bruno Windels 2021-03-02 19:31:00 +01:00
parent 6f6346d5c3
commit e1821b1753
2 changed files with 16 additions and 8 deletions

View File

@ -441,7 +441,7 @@ export class Room extends EventEmitter {
storage: this._storage,
fragmentIdComparer: this._fragmentIdComparer,
});
gapResult = await gapWriter.writeFragmentFill(fragmentEntry, response, txn);
gapResult = await gapWriter.writeFragmentFill(fragmentEntry, response, txn, log);
} catch (err) {
txn.abort();
throw err;

View File

@ -26,7 +26,7 @@ export class GapWriter {
this._fragmentIdComparer = fragmentIdComparer;
}
// events is in reverse-chronological order (last event comes at index 0) if backwards
async _findOverlappingEvents(fragmentEntry, events, txn) {
async _findOverlappingEvents(fragmentEntry, events, txn, log) {
let expectedOverlappingEventId;
if (fragmentEntry.hasLinkedFragment) {
expectedOverlappingEventId = await this._findExpectedOverlappingEventId(fragmentEntry, txn);
@ -49,8 +49,12 @@ export class GapWriter {
// TODO: check here that the neighbourEvent is at the correct edge of it's fragment
// get neighbour fragment to link it up later on
const neighbourEvent = await txn.timelineEvents.getByEventId(this._roomId, duplicateEventId);
const neighbourFragment = await txn.timelineFragments.get(this._roomId, neighbourEvent.fragmentId);
neighbourFragmentEntry = fragmentEntry.createNeighbourEntry(neighbourFragment);
if (neighbourEvent.fragmentId === fragmentEntry.fragmentId) {
log.log("hit #160, prevent fragment linking to itself", log.level.Warn);
} else {
const neighbourFragment = await txn.timelineFragments.get(this._roomId, neighbourEvent.fragmentId);
neighbourFragmentEntry = fragmentEntry.createNeighbourEntry(neighbourFragment);
}
// trim overlapping events
remainingEvents = null;
} else {
@ -192,10 +196,11 @@ export class GapWriter {
return changedFragments;
}
async writeFragmentFill(fragmentEntry, response, txn) {
async writeFragmentFill(fragmentEntry, response, txn, log) {
const {fragmentId, direction} = fragmentEntry;
// chunk is in reverse-chronological order when backwards
const {chunk, start, end, state} = response;
const {chunk, start, state} = response;
let {end} = response;
let entries;
if (!Array.isArray(chunk)) {
@ -229,8 +234,11 @@ export class GapWriter {
const {
nonOverlappingEvents,
neighbourFragmentEntry
} = await this._findOverlappingEvents(fragmentEntry, chunk, txn);
} = await this._findOverlappingEvents(fragmentEntry, chunk, txn, log);
if (!neighbourFragmentEntry && nonOverlappingEvents.length === 0) {
log.log("hit #160, clearing token", log.level.Warn);
end = null;
}
// create entries for all events in chunk, add them to entries
entries = this._storeEvents(nonOverlappingEvents, lastKey, direction, state, txn);
const fragments = await this._updateFragments(fragmentEntry, neighbourFragmentEntry, end, entries, txn);