gradido/config-schema/src/log4js-config/appenders.ts

import type {
  Appender,
  DateFileAppender,
  LogLevelFilterAppender,
  StandardOutputAppender,
} from 'log4js'
import { CustomFileAppender } from './types'

const fileAppenderTemplate = {
  type: 'dateFile' as const,
  pattern: 'yyyy-MM-dd',
  compress: true,
  keepFileExt: true,
  fileNameSep: '_',
  numBackups: 30,
}

const defaultAppenders = {
  errorFile: {
    type: 'dateFile' as const,
    filename: 'errors.log',
    pattern: 'yyyy-MM-dd',
    layout: { type: 'coloredContext' as const, withStack: true },
    compress: true,
    keepFileExt: true,
    fileNameSep: '_',
    numBackups: 30,
  } as DateFileAppender,
  errors: {
    type: 'logLevelFilter' as const,
    level: 'error' as const,
    appender: 'errorFile' as const,
  } as LogLevelFilterAppender,
  out: {
    type: 'stdout' as const,
    layout: { type: 'coloredContext' as const, withStack: 'error' },
  } as StandardOutputAppender,
}

/**
 * Creates the appender configuration for log4js.
 *
 * @param {CustomFileAppender[]} fileAppenders
 *   the list of custom file appenders to add to the standard
 *   appenders.
 * @param {string} [basePath]
 *   the base path for all log files.
 * @param {boolean} [stacktraceOnStdout=false]
 *   whether to show the stacktrace on the standard output
 *   appender.
 * @returns {Object<string, Appender>}
 *   the appender configuration as a map
 */
export function createAppenderConfig(
  fileAppenders: CustomFileAppender[],
  basePath?: string,
): { [name: string]: Appender } {
  if (basePath) {
    defaultAppenders.errorFile.filename = `${basePath}/errors.log`
  }
  const customAppender: { [name: string]: Appender } = { ...defaultAppenders }

  fileAppenders.forEach((appender) => {
    const filename = appender.filename ?? `${appender.name}.log`
    const dateFile: DateFileAppender = {
      ...fileAppenderTemplate,
      filename: basePath ? `${basePath}/${filename}` : filename,
    }
    dateFile.layout = {
      type: 'coloredContext',
      ...appender.layout,
    }
    customAppender[appender.name] = dateFile
  })
  return customAppender
}