update-env script

gistfile1.txt

#!/usr/bin/env node

/**
 * Usage:
 * 
 * ./update-env.mjs \
 *   --KEY=value \
 *   --KEY2=value \
 *   --key3="Values with spaces need quotes" \
 *   --K "The assignment operator after a flag is optional"
 *   etc
 * 
 * or optionally specify a .env path:
 * ./update-env.mjs \
 *   --__ENV_PATH=/path/to/some/file \
 *   --KEY=value \
 *   etc
 */
import { existsSync, readFileSync, writeFileSync } from 'fs'
import { join, dirname } from 'path'
import { fileURLToPath } from 'url'

const __dirname = dirname(fileURLToPath(import.meta.url))

function updateEnv(varName, value, envPath) {
  if (!existsSync(envPath)) {
    writeFileSync(envPath, '')
  }

  const content = readFileSync(envPath, 'utf8')
  const lines = content.split('\n')

  let found = false
  for (let i = 0; i < lines.length; i++) {
    if (lines[i].startsWith(`${varName}=`)) {
      lines[i] = `${varName}=${value}`
      found = true
      break
    }
  }

  if (!found) {
    lines.push(`${varName}=${value}`)
  }

  writeFileSync(
    envPath,
    lines.filter(line => line.trim() !== '').join('\n') + '\n'
  )
}

const args = process.argv.slice(2)
const configs = {}

for (let i = 0; i < args.length; i++) {
  if (args[i].startsWith('--')) {
    const keySegment = args[i].slice(2)

    if (keySegment.includes('=')) {
      const [key, value] = keySegment.split('=')
      configs[key] = value
    } else if (i + 1 < args.length && !args[i + 1].startsWith('--')) {
      const key = keySegment
      const value = args[++i]
      configs[key] = value
    } else {
      configs[keySegment] = 'true'
    }
  }
}

if (!Object.keys(configs).length) {
  console.log(
    'Usage: configure-env.mjs --<CONFIG_NAME>=<CONFIG_VALUE>, --<CONFIG_NAME> <CONFIG_VALUE>, or --<CONFIG_NAME>'
  )
  process.exit(1)
}

let envPath = join(__dirname, '..', '.env')
if (configs.__ENV_PATH) {
  envPath = configs.__ENV_PATH
  delete configs.__ENV_PATH
}

for (const [configName, configValue] of Object.entries(configs)) {
  updateEnv(configName, configValue, envPath)
}