ls-deno/log.ts

import { type LogConfig } from "@/config.ts";
import * as log from "$std/log/mod.ts";
import { format } from "https://deno.land/std@0.163.0/node/util.ts";

export * as log from "$std/log/mod.ts";

const short: Record<number, string> = {
  10: "DBG",
  20: "INF",
  30: "WRN",
  40: "ERR",
  50: "CRT",
};

const levelColors: Record<number, string> = {
  10: "90",
  20: "34",
  30: "33",
  40: "31",
  50: "35",
};

const msgColors: Record<number, string> = {
  40: "31",
  50: "31",
};

class CustomConsoleHandler extends log.handlers.ConsoleHandler {
  encoder: TextEncoder;

  constructor(levelName: log.LevelName, options: log.HandlerOptions) {
    super(levelName, options);
    this.encoder = new TextEncoder();
  }

  override log(msg: string): Promise<number> {
    const result = Deno.stdout.write(
      this.encoder.encode(msg),
    );
    Deno.stdout.write(new Uint8Array([0x0a]));
    return result;
  }
}

export function setupLoggers(config: LogConfig, redact?: RegExp) {
  // TODO: check support for colors and adjust as needed
  log.setup({
    handlers: {
      console: new CustomConsoleHandler(
        config.consoleLevelName,
        {
          formatter: ({ level, datetime, msg, args }: log.LogRecord) => {
            let fullMessage = format(
              msg,
              ...args,
            );
            if (redact) {
              fullMessage = fullMessage.replaceAll(redact, "<REDACTED>");
            }
            return `\x1b[m[\x1b[${levelColors[level] || ""}m${
              short[level] || "UNK"
            }\x1b[m] \x1b[90m${datetime.toISOString()}\x1b[m \x1b[${
              msgColors[level] || ""
            }m${fullMessage}\x1b[m`;
          },
        },
      ),
    },
    loggers: {
      default: {
        level: "DEBUG",
        handlers: ["console", "file"],
      },
      tasks: {
        level: "ERROR",
        handlers: ["console"],
      },
    },
  });

  /*
  console.debug = log.debug;
  console.info = log.info;
  console.warn = log.warning;
  console.error = log.error;
  */

  /*
  log.debug("Debug Log");
  log.info("Info Log");
  log.warning("Warning Log");
  log.error("Error Log");
  log.critical("Critical Log");
  */

  log.info("Logger setup complete");
}