Files
SponsorBlockServer/src/routes/getSkipSegments.ts
2021-12-31 14:04:20 -05:00

431 lines
18 KiB
TypeScript

import { Request, Response } from "express";
import { partition } from "lodash";
import { config } from "../config";
import { db, privateDB } from "../databases/databases";
import { skipSegmentsHashKey, skipSegmentsKey, skipSegmentGroupsKey } from "../utils/redisKeys";
import { SBRecord } from "../types/lib.model";
import { ActionType, Category, CategoryActionType, DBSegment, HashedIP, IPAddress, OverlappingSegmentGroup, Segment, SegmentCache, SegmentUUID, Service, VideoData, VideoID, VideoIDHash, Visibility, VotableObject } from "../types/segments.model";
import { getCategoryActionType } from "../utils/categoryInfo";
import { getHashCache } from "../utils/getHashCache";
import { getIP } from "../utils/getIP";
import { Logger } from "../utils/logger";
import { QueryCacher } from "../utils/queryCacher";
import { getReputation } from "../utils/reputation";
import { getService } from "../utils/getService";
async function prepareCategorySegments(req: Request, videoID: VideoID, service: Service, segments: DBSegment[], cache: SegmentCache = { shadowHiddenSegmentIPs: {} }, useCache: boolean): Promise<Segment[]> {
const shouldFilter: boolean[] = await Promise.all(segments.map(async (segment) => {
if (segment.votes < -1 && !segment.required) {
return false; //too untrustworthy, just ignore it
}
//check if shadowHidden
//this means it is hidden to everyone but the original ip that submitted it
if (segment.shadowHidden != Visibility.HIDDEN) {
return true;
}
if (cache.shadowHiddenSegmentIPs[videoID] === undefined) cache.shadowHiddenSegmentIPs[videoID] = {};
if (cache.shadowHiddenSegmentIPs[videoID][segment.timeSubmitted] === undefined) {
const service = getService(req?.query?.service as string);
cache.shadowHiddenSegmentIPs[videoID][segment.timeSubmitted] = await privateDB.prepare("all", 'SELECT "hashedIP" FROM "sponsorTimes" WHERE "videoID" = ? AND "timeSubmitted" = ? AND "service" = ?',
[videoID, segment.timeSubmitted, service]) as { hashedIP: HashedIP }[];
}
const ipList = cache.shadowHiddenSegmentIPs[videoID][segment.timeSubmitted];
if (ipList?.length > 0 && cache.userHashedIP === undefined) {
//hash the IP only if it's strictly necessary
cache.userHashedIP = await getHashCache((getIP(req) + config.globalSalt) as IPAddress);
}
//if this isn't their ip, don't send it to them
const shouldShadowHide = cache.shadowHiddenSegmentIPs[videoID][segment.timeSubmitted]?.some(
(shadowHiddenSegment) => shadowHiddenSegment.hashedIP === cache.userHashedIP) ?? false;
if (shouldShadowHide) useCache = false;
return shouldShadowHide;
}));
const filteredSegments = segments.filter((_, index) => shouldFilter[index]);
return (await chooseSegments(videoID, service, filteredSegments, useCache)).map((chosenSegment) => ({
category: chosenSegment.category,
actionType: chosenSegment.actionType,
segment: [chosenSegment.startTime, chosenSegment.endTime],
UUID: chosenSegment.UUID,
locked: chosenSegment.locked,
votes: chosenSegment.votes,
videoDuration: chosenSegment.videoDuration,
userID: chosenSegment.userID,
description: chosenSegment.description
}));
}
async function getSegmentsByVideoID(req: Request, videoID: VideoID, categories: Category[],
actionTypes: ActionType[], requiredSegments: SegmentUUID[], service: Service): Promise<Segment[]> {
const cache: SegmentCache = { shadowHiddenSegmentIPs: {} };
try {
categories = categories.filter((category) => !/[^a-z|_|-]/.test(category));
if (categories.length === 0) return null;
const segments: DBSegment[] = (await getSegmentsFromDBByVideoID(videoID, service))
.map((segment: DBSegment) => {
if (filterRequiredSegments(segment.UUID, requiredSegments)) segment.required = true;
return segment;
}, {});
const canUseCache = requiredSegments.length === 0;
const processedSegments: Segment[] = await prepareCategorySegments(req, videoID, service, segments, cache, canUseCache);
return processedSegments.filter((segment: Segment) => categories.includes(segment?.category) && actionTypes.includes(segment?.actionType));
} catch (err) {
if (err) {
Logger.error(err as string);
return null;
}
}
}
async function getSegmentsByHash(req: Request, hashedVideoIDPrefix: VideoIDHash, categories: Category[],
actionTypes: ActionType[], requiredSegments: SegmentUUID[], service: Service): Promise<SBRecord<VideoID, VideoData>> {
const cache: SegmentCache = { shadowHiddenSegmentIPs: {} };
const segments: SBRecord<VideoID, VideoData> = {};
try {
type SegmentWithHashPerVideoID = SBRecord<VideoID, { hash: VideoIDHash, segments: DBSegment[] }>;
categories = categories.filter((category) => !(/[^a-z|_|-]/.test(category)));
if (categories.length === 0) return null;
const segmentPerVideoID: SegmentWithHashPerVideoID = (await getSegmentsFromDBByHash(hashedVideoIDPrefix, service))
.reduce((acc: SegmentWithHashPerVideoID, segment: DBSegment) => {
acc[segment.videoID] = acc[segment.videoID] || {
hash: segment.hashedVideoID,
segments: []
};
if (filterRequiredSegments(segment.UUID, requiredSegments)) segment.required = true;
acc[segment.videoID].segments ??= [];
acc[segment.videoID].segments.push(segment);
return acc;
}, {});
for (const [videoID, videoData] of Object.entries(segmentPerVideoID)) {
const data: VideoData = {
hash: videoData.hash,
segments: [],
};
const canUseCache = requiredSegments.length === 0;
data.segments = (await prepareCategorySegments(req, videoID as VideoID, service, videoData.segments, cache, canUseCache))
.filter((segment: Segment) => categories.includes(segment?.category) && actionTypes.includes(segment?.actionType));
if (data.segments.length > 0) {
segments[videoID] = data;
}
}
return segments;
} catch (err) {
Logger.error(err as string);
return null;
}
}
async function getSegmentsFromDBByHash(hashedVideoIDPrefix: VideoIDHash, service: Service): Promise<DBSegment[]> {
const fetchFromDB = () => db
.prepare(
"all",
`SELECT "videoID", "startTime", "endTime", "votes", "locked", "UUID", "userID", "category", "actionType", "videoDuration", "reputation", "shadowHidden", "hashedVideoID", "timeSubmitted", "description" FROM "sponsorTimes"
WHERE "hashedVideoID" LIKE ? AND "service" = ? AND "hidden" = 0 ORDER BY "startTime"`,
[`${hashedVideoIDPrefix}%`, service]
) as Promise<DBSegment[]>;
if (hashedVideoIDPrefix.length === 4) {
return await QueryCacher.get(fetchFromDB, skipSegmentsHashKey(hashedVideoIDPrefix, service));
}
return await fetchFromDB();
}
async function getSegmentsFromDBByVideoID(videoID: VideoID, service: Service): Promise<DBSegment[]> {
const fetchFromDB = () => db
.prepare(
"all",
`SELECT "startTime", "endTime", "votes", "locked", "UUID", "userID", "category", "actionType", "videoDuration", "reputation", "shadowHidden", "timeSubmitted", "description" FROM "sponsorTimes"
WHERE "videoID" = ? AND "service" = ? AND "hidden" = 0 ORDER BY "startTime"`,
[videoID, service]
) as Promise<DBSegment[]>;
return await QueryCacher.get(fetchFromDB, skipSegmentsKey(videoID, service));
}
// Gets a weighted random choice from the choices array based on their `votes` property.
// amountOfChoices specifies the maximum amount of choices to return, 1 or more.
// Choices are unique
// If a predicate is given, it will only filter choices following it, and will leave the rest in the list
function getWeightedRandomChoice<T extends VotableObject>(choices: T[], amountOfChoices: number, predicate?: (choice: T) => void): T[] {
//trivial case: no need to go through the whole process
if (amountOfChoices >= choices.length) {
return choices;
}
type TWithWeight = T & {
weight: number
}
let forceIncludedChoices: T[] = [];
let filteredChoices = choices;
if (predicate) {
const splitArray = partition(choices, predicate);
filteredChoices = splitArray[0];
forceIncludedChoices = splitArray[1];
}
//assign a weight to each choice
let totalWeight = 0;
const choicesWithWeights: TWithWeight[] = filteredChoices.map(choice => {
const boost = Math.min(choice.reputation, 4);
//The 3 makes -2 the minimum votes before being ignored completely
//this can be changed if this system increases in popularity.
const weight = Math.exp(choice.votes * Math.max(1, choice.reputation + 1) + 3 + boost);
totalWeight += Math.max(weight, 0);
return { ...choice, weight };
});
// Nothing to filter for
if (amountOfChoices >= choicesWithWeights.length) {
return choices;
}
//iterate and find amountOfChoices choices
const chosen = [...forceIncludedChoices];
while (amountOfChoices-- > 0) {
//weighted random draw of one element of choices
const randomNumber = Math.random() * totalWeight;
let stackWeight = choicesWithWeights[0].weight;
let i = 0;
while (stackWeight < randomNumber) {
stackWeight += choicesWithWeights[++i].weight;
}
//add it to the chosen ones and remove it from the choices before the next iteration
chosen.push(choicesWithWeights[i]);
totalWeight -= choicesWithWeights[i].weight;
choicesWithWeights.splice(i, 1);
}
return chosen;
}
async function chooseSegments(videoID: VideoID, service: Service, segments: DBSegment[], useCache: boolean): Promise<DBSegment[]> {
const fetchData = async () => await buildSegmentGroups(segments);
const groups = useCache
? await QueryCacher.get(fetchData, skipSegmentGroupsKey(videoID, service))
: await fetchData();
// Filter for only 1 item for POI categories
return getWeightedRandomChoice(groups, 1, (choice) => getCategoryActionType(choice.segments[0].category) === CategoryActionType.POI)
.map(//randomly choose 1 good segment per group and return them
group => getWeightedRandomChoice(group.segments, 1)[0]
);
}
//This function will find segments that are contained inside of eachother, called similar segments
//Only one similar time will be returned, randomly generated based on the sqrt of votes.
//This allows new less voted items to still sometimes appear to give them a chance at getting votes.
//Segments with less than -1 votes are already ignored before this function is called
async function buildSegmentGroups(segments: DBSegment[]): Promise<OverlappingSegmentGroup[]> {
//Create groups of segments that are similar to eachother
//Segments must be sorted by their startTime so that we can build groups chronologically:
//1. As long as the segments' startTime fall inside the currentGroup, we keep adding them to that group
//2. If a segment starts after the end of the currentGroup (> cursor), no other segment will ever fall
// inside that group (because they're sorted) so we can create a new one
let overlappingSegmentsGroups: OverlappingSegmentGroup[] = [];
let currentGroup: OverlappingSegmentGroup;
let cursor = -1; //-1 to make sure that, even if the 1st segment starts at 0, a new group is created
for (const segment of segments) {
if (segment.startTime >= cursor) {
currentGroup = { segments: [], votes: 0, reputation: 0, locked: false, required: false };
overlappingSegmentsGroups.push(currentGroup);
}
currentGroup.segments.push(segment);
//only if it is a positive vote, otherwise it is probably just a sponsor time with slightly wrong time
if (segment.votes > 0) {
currentGroup.votes += segment.votes;
}
if (segment.userID) segment.reputation = Math.min(segment.reputation, await getReputation(segment.userID));
if (segment.reputation > 0) {
currentGroup.reputation += segment.reputation;
}
if (segment.locked) {
currentGroup.locked = true;
}
if (segment.required) {
currentGroup.required = true;
}
cursor = Math.max(cursor, segment.endTime);
}
overlappingSegmentsGroups = splitPercentOverlap(overlappingSegmentsGroups);
overlappingSegmentsGroups.forEach((group) => {
if (group.required) {
// Required beats locked
group.segments = group.segments.filter((segment) => segment.required);
} else if (group.locked) {
group.segments = group.segments.filter((segment) => segment.locked);
}
group.reputation = group.reputation / group.segments.length;
});
//if there are too many groups, find the best ones
return overlappingSegmentsGroups;
}
function splitPercentOverlap(groups: OverlappingSegmentGroup[]): OverlappingSegmentGroup[] {
return groups.flatMap((group) => {
const result: OverlappingSegmentGroup[] = [];
group.segments.forEach((segment) => {
const bestGroup = result.find((group) => {
// At least one segment in the group must have high % overlap or the same action type
// Since POI segments will always have 0 overlap, they will always be in their own groups
return group.segments.some((compareSegment) => {
const overlap = Math.min(segment.endTime, compareSegment.endTime) - Math.max(segment.startTime, compareSegment.startTime);
const overallDuration = Math.max(segment.endTime, compareSegment.endTime) - Math.min(segment.startTime, compareSegment.startTime);
const overlapPercent = overlap / overallDuration;
return (overlapPercent > 0 && segment.actionType === compareSegment.actionType && segment.category === compareSegment.category && segment.actionType !== ActionType.Chapter)
|| (overlapPercent >= 0.6 && segment.actionType !== compareSegment.actionType && segment.category === compareSegment.category)
|| (overlapPercent >= 0.95 && segment.actionType === compareSegment.actionType && segment.category !== compareSegment.category
&& segment.category !== "music_offtopic" && compareSegment.category !== "music_offtopic")
|| (overlapPercent >= 0.8 && segment.actionType === ActionType.Chapter && compareSegment.actionType === ActionType.Chapter);
});
});
if (bestGroup) {
bestGroup.segments.push(segment);
bestGroup.votes += segment.votes;
bestGroup.reputation += segment.reputation;
bestGroup.locked ||= segment.locked;
bestGroup.required ||= segment.required;
} else {
result.push({ segments: [segment], votes: segment.votes, reputation: segment.reputation, locked: segment.locked, required: segment.required });
}
});
return result;
});
}
/**
*
* Returns what would be sent to the client.
* Will respond with errors if required. Returns false if it errors.
*
* @param req
* @param res
*
* @returns
*/
async function handleGetSegments(req: Request, res: Response): Promise<Segment[] | false> {
const videoID = req.query.videoID as VideoID;
if (!videoID) {
res.status(400).send("videoID not specified");
return false;
}
// Default to sponsor
// If using params instead of JSON, only one category can be pulled
const categories: Category[] = req.query.categories
? JSON.parse(req.query.categories as string)
: req.query.category
? Array.isArray(req.query.category)
? req.query.category
: [req.query.category]
: ["sponsor"];
if (!Array.isArray(categories)) {
res.status(400).send("Categories parameter does not match format requirements.");
return false;
}
const actionTypes: ActionType[] = req.query.actionTypes
? JSON.parse(req.query.actionTypes as string)
: req.query.actionType
? Array.isArray(req.query.actionType)
? req.query.actionType
: [req.query.actionType]
: [ActionType.Skip];
if (!Array.isArray(actionTypes)) {
res.status(400).send("actionTypes parameter does not match format requirements.");
return false;
}
const requiredSegments: SegmentUUID[] = req.query.requiredSegments
? JSON.parse(req.query.requiredSegments as string)
: req.query.requiredSegment
? Array.isArray(req.query.requiredSegment)
? req.query.requiredSegment
: [req.query.requiredSegment]
: [];
if (!Array.isArray(requiredSegments)) {
res.status(400).send("requiredSegments parameter does not match format requirements.");
return false;
}
const service = getService(req.query.service, req.body.service);
const segments = await getSegmentsByVideoID(req, videoID, categories, actionTypes, requiredSegments, service);
if (segments === null || segments === undefined) {
res.sendStatus(500);
return false;
}
if (segments.length === 0) {
res.sendStatus(404);
return false;
}
return segments;
}
const filterRequiredSegments = (UUID: SegmentUUID, requiredSegments: SegmentUUID[]): boolean => {
for (const search of requiredSegments) {
if (search === UUID || UUID.indexOf(search) == 0) return true;
}
return false;
};
async function endpoint(req: Request, res: Response): Promise<Response> {
try {
const segments = await handleGetSegments(req, res);
// If false, res.send has already been called
if (segments) {
//send result
return res.send(segments);
}
} catch (err) {
if (err instanceof SyntaxError) {
return res.status(400).send("Categories parameter does not match format requirements.");
} else return res.sendStatus(500);
}
}
export {
getSegmentsByVideoID,
getSegmentsByHash,
endpoint,
handleGetSegments
};