ensure env vars

ensureEnvVars

#!/usr/bin/env tsx

import {readdirSync, readFileSync} from 'fs'
import {join, resolve} from 'path'
import {config} from 'dotenv'

config({quiet: true})

const WHITELISTED = [
  // injected by aws
  '_X_AMZN_TRACE_ID',
  // these are basically vars for local / dev shtuff
  'APPCONFIG_LOCAL',
  'NODE_ENV',
]

// Recursively collect .js/.ts/.jsx/.tsx files asynchronously
async function getAllFiles(dir: string): Promise<string[]> {
  const entries = readdirSync(dir, {withFileTypes: true})
  const files: string[] = []

  await Promise.all(
    entries.map(async (entry) => {
      const fullPath = join(dir, entry.name)
      if (entry.isDirectory()) {
        const subFiles = await getAllFiles(fullPath)
        files.push(...subFiles)
      } else if (/\.ts$/.test(entry.name)) {
        files.push(fullPath)
      }
    }),
  )

  return files
}

async function findEnvVariablesInFiles(files: string[]): Promise<string[]> {
  const envVarRegex = /process\.env\.([a-zA-Z_][a-zA-Z0-9_]*)/g

  const allMatches = await Promise.all(
    files.map((file) => {
      const content = readFileSync(file, 'utf8')
      const matches = new Set<string>()

      let match
      while ((match = envVarRegex.exec(content)) !== null) {
        matches.add(match[1]!)
      }

      return Array.from(matches)
    }),
  )

  return Array.from(new Set(allMatches.flat()))
}

function getEnvVars(): string[] {
  return Object.keys(process.env)
}

;(async function main() {
  const targetDirs = ['src/functions', 'src/shared']

  // Collect files from all directories in parallel
  const allFiles = (await Promise.all(targetDirs.map((dir) => getAllFiles(resolve(dir))))).flat()
  const allEnvVars = getEnvVars()
  const missingVars = (await findEnvVariablesInFiles(allFiles)).filter(
    (name) => !WHITELISTED.includes(name) && !allEnvVars.includes(name),
  )

  if (missingVars.length > 0) {
    process.stderr.write(`❌ Missing environment variables: ${missingVars.join('; ')}\n`)
    process.exit(1)
  }

  process.stderr.write('✅ All environment variables are set.\n')
  process.exit(0)
})()