Using JavaScript to analyze Splinterlands Battle Data

I got most of the script from a splinterlands bot. I get 50 battles from history with API and get my previous opponents 50 battles and store them in a file.

Complete code can be found at battles-data

Get Battles from API

async function getBattleHistory(player = '', data = {}) {
    const battleHistory = await fetch('https://api.steemmonsters.io/battle/history?player=' + player)
    // Code //
    return battleHistory.battles;
}

The above function will retrieve 50 battles history for a given player. 50 battles because that is the limit set by the API. Before I gather all the battles I obtain the list of all opponents of a player and get the battles for them along with the player. By taking the battles from the player would set the level of the players and tier information to be relevant. For a bronze tier player, a silver tier player's information is useless because the cards used will be different and of different levels.

First Promise

getBattleHistory(process.env.ACCOUNT)
  .then(u => u.map(x => {
    return [x.player_1, x.player_2]
  }).flat().filter(distinct))

  .then(u => u.map(x => {
    return [x.player_1, x.player_2]

  .flat().filter(distinct))

Promise each player

let promises = []; -> start with empty promises.

For each player above we push a promise, to the above array, to getBattleHistory(player). We extract information from a battle using extractGeneralInfo and extractMonster from the battle and teams respectively. each monster and the summoner details will be as follows:

      summoner: {
        id:      team.summoner.card_detail_id,
        level:   team.summoner.level,
        gold:    team.summoner.gold,
      },

This will boil down to:

  .then(ul => ul.map(user => {

    promises.push(

      getBattleHistory(user)
 .then(battles => battles.map(
 //extractGeneralInfo
 //extractMonster
))
 .then(x => battlesList = [...battlesList, ...x])
)

Keeping all promises

The final part is to save all the information to a JSON file, which can be used later or analyzed further.

  .then(() => Promise.all(promises).then(() => {

    fs.readFile(./data/${process.env.ACCOUNT}_history_tt.json, 'utf8', (err, data) => {

      fs.writeFile(data/${process.env.ACCOUNT}_history_tt.json, JSON.stringify(cleanBattleList), function (err) {

I found the concept of Promise in JavaScript quite puzzling at first, but when I understood it, it was quite simple and elegant. Adding the promise array to gather all the promises was the result of a lot of StackOverflow research.

Credits

• NeoVim for an editor
• WezTerm for terminal
• splinterlands-bot for most of this code like 80%