buildpath/match_collector/index.js

const base = "https://euw1.api.riotgames.com"
const api_key = process.env.RIOT_API_KEY
const sleep_minutes = 3

var champion_stat = require("./champion_stat")

main()

async function main() {
    console.log("MatchCollector - Hello !");
    const client = await connectToDatabase();
    const [latestPatch, latestPatchTime] = await fetchLatestPatchDate(client);
    console.log("Connected to database, latest patch " + latestPatch + " was epoch: " + latestPatchTime)

    const alreadySeenGameList = await alreadySeenGames(client, latestPatch);
    console.log("We already have " + alreadySeenGameList.length + " matches for this patch !")
    
    const challengerLeague = await fetchChallengerLeague();
    console.log("ChallengerLeague: got " + challengerLeague.entries.length + " entries");

    const gameList = [];
    let i = 0;
    for(let challenger of challengerLeague.entries) {
        console.log("Entry " + i + "/" + challengerLeague.entries.length + " ...")
        const puuid = await summonerPuuid(challenger.summonerId);
        const challengerGameList = await summonerGameList(puuid, latestPatchTime);
        for(let game of challengerGameList) {
            if(!gameList.includes(game) && !alreadySeenGameList.includes(game)) {
                gameList.push(game)
            }
        }
        i++;
    }
    
    console.log("Games: got " + gameList.length + " entries");
    i = 0;
    for(let game of gameList) {
        console.log("Entry " + i + "/" + gameList.length + " ...")
        const gameMatch = await match(game)
        const gameTimeline = await matchTimeline(game)
        gameMatch.timeline = gameTimeline
        await saveMatch(client, gameMatch, latestPatch)
        i++;
    }

    console.log("Generating stats...");
    await champion_stat.makeChampionsStats(client, latestPatch)

    console.log("All done. Closing client.");
    await client.close()
}

async function handleRateLimit(url) {
    let response = await fetch(url)
    if(response.status == 429) {
        await new Promise(resolve => setTimeout(resolve, sleep_minutes * 60 * 1000))
        response = handleRateLimit(url)
    }

    return response
}

function handleError(response) {
    if(!response.ok) {
        console.log("Error during fetch(" + response.url + "): STATUS " + response.status + " (" + response.statusText + ")");
        process.exit(1);
    }
}

async function connectToDatabase() {
    const { MongoClient, ServerApiVersion } = require("mongodb");
    // Create a MongoClient with a MongoClientOptions object to set the Stable API version
    const client = new MongoClient(`mongodb://${process.env.MONGO_USER}:${process.env.MONGO_PASS}@mongo:27017`)
    await client.connect()
    return client
}

async function fetchLatestPatchDate(client) {
    const database = client.db("patches");
    const patches = database.collection("patches");
    const latestPatch = await patches.find().limit(1).sort({date:-1}).next()
    return [latestPatch.patch, Math.floor(latestPatch.date.valueOf() / 1000)]
}

async function fetchChallengerLeague() {
    const queue = "RANKED_SOLO_5x5"
    const endpoint = `/lol/league/v4/challengerleagues/by-queue/${queue}`
    const url = `${base}${endpoint}?api_key=${api_key}`

    const challengerLeagueResponse = await handleRateLimit(url);
    
    handleError(challengerLeagueResponse)

    const challengerLeague = await challengerLeagueResponse.json();
    return challengerLeague;
}

async function summonerPuuid(summonerId) {
    const endpoint = `/lol/summoner/v4/summoners/${summonerId}`
    const url = `${base}${endpoint}?api_key=${api_key}`

    const puuidResponse = await handleRateLimit(url);
    handleError(puuidResponse)
    const puuidJson = await puuidResponse.json();

    return puuidJson.puuid;
}
async function summonerGameList(puuid, startTime) {
    const base = "https://europe.api.riotgames.com"
    const endpoint = `/lol/match/v5/matches/by-puuid/${puuid}/ids`;
    const url = `${base}${endpoint}?queue=420&type=ranked&startTime=${startTime}&api_key=${api_key}`

    const gameListResponse = await handleRateLimit(url);
    handleError(gameListResponse)
    const gameList = await gameListResponse.json();

    return gameList;
}

async function match(matchId) {
    const base = "https://europe.api.riotgames.com"
    const endpoint = `/lol/match/v5/matches/${matchId}`
    const url = `${base}${endpoint}?api_key=${api_key}`

    const matchResponse = await handleRateLimit(url)
    handleError(matchResponse)
    const match = await matchResponse.json();

    return match;
}

async function matchTimeline(matchId) {
    const base = "https://europe.api.riotgames.com"
    const endpoint = `/lol/match/v5/matches/${matchId}/timeline`
    const url = `${base}${endpoint}?api_key=${api_key}`

    const timelineResponse = await handleRateLimit(url)
    handleError(timelineResponse)
    const timeline = await timelineResponse.json();

    return timeline
}

async function alreadySeenGames(client, latestPatch) {
    const database = client.db("matches")
    const matches = database.collection(latestPatch)

    const alreadySeen = await matches.distinct("metadata.matchId")
    return alreadySeen
}

async function saveMatch(client, match, latestPatch) {
    const database = client.db("matches")
    const matches = database.collection(latestPatch)
    await matches.insertOne(match)
}