winston-discord-webhook/index.js

Transport for winston to send logs on Discord via Webhook

const Transport = require("winston-transport");
const { WebhookClient } = require("discord.js");
const { EmbedBuilder } = require("discord.js");

function postEmbeds(queue, hook) {
  const embeds = [];
  while (embeds.length < 10 && queue.length > 0) {
    embeds.push(queue.shift());
  }

  if (embeds.length == 0) return;

  return hook.send({ embeds });
}

module.exports = class DiscordTransport extends Transport {
  /**
   *
   * @param {Object} opts Options for Discord Transport
   * @param {string} opts.webhook Webhook URL to send logs to
   * @param {string} opts.mode Mode to use. 'codeblock' or 'embed' or 'hybrid' or 'standard' Default: hybrid
   * @param {Map<string, string>} opts.colors Colors to use for embeds depending on log level.
   * @param {number} opts.interval Interval to send messages in queue. Default: 2500
   * @param {number} opts.maxLength Maximum length of a message to send. Default: 1900
   */
  constructor(opts) {
    super(opts);

    if (!opts.webhook) {
      throw new Error("No webhook given for Discord Transport");
    }

    /**
     * @type {boolean}
     */
    this.mode = opts.mode || "hybrid";
    this.colors = opts.colors || new Map();

    /**
     * @type {number}
     */
    this.interval = opts.interval || 2500;

    /**
     * @type {number}
     */
    this.maxLength = opts.maxLength || 1900;

    this.queue = [];
    this.hook = new WebhookClient({ url: opts.webhook });

    if (this.mode == "embed" || this.mode == "hybrid") {
      setInterval(() => {
        postEmbeds(this.queue, this.hook);
      }, this.interval);
    } else {
      setInterval(() => {
        const content = [];

        while (content.length < this.maxLength) {
          content.push(this.queue.shift());
        }

        if (content.length == 0) return;

        if (content != "") {
          this.hook.send({ content: content.join("\n") });
        }
      }, this.interval);
    }
  }

  log(info, callback) {
    setImmediate(() => {
      this.emit("logged", info);

      if (["hybrid", "embed"].includes(this.mode)) {
        const embed = new EmbedBuilder();

        if (this.colors.has(info[Symbol.for("level")]))
          embed.setColor(this.colors.get(info[Symbol.for("level")]));

        if (this.mode == "hybrid") {
          embed.setDescription(`\`\`\`ansi\n${info[Symbol.for("message")]}\`\`\``);
        } else {
          embed.setDescription(info[Symbol.for("message")]);
        }
        this.queue.push(embed);
      } else if (this.mode == "codeblock") {
        this.queue.push(`\`\`\`ansi\n${info[Symbol.for("message")]}\n\n\n`);
      } else {
        this.queue.push(info[Symbol.for("message")]);
      }
    });

    callback();
  }
};