one/src/daemon/utils.ts

One is a new React Framework that makes Vite serve both native and web.

// daemon utility functions

import * as fs from 'node:fs'
import * as path from 'node:path'

export interface AppConfig {
  expo?: {
    name?: string
    slug?: string
    ios?: {
      bundleIdentifier?: string
    }
    android?: {
      package?: string
    }
  }
  // bare RN config
  name?: string
}

export function getBundleIdFromConfig(root: string): string | undefined {
  const appJsonPath = path.join(root, 'app.json')

  if (!fs.existsSync(appJsonPath)) {
    return undefined
  }

  try {
    const appConfig: AppConfig = JSON.parse(fs.readFileSync(appJsonPath, 'utf-8'))

    // try expo config first
    if (appConfig.expo?.ios?.bundleIdentifier) {
      return appConfig.expo.ios.bundleIdentifier
    }

    if (appConfig.expo?.android?.package) {
      return appConfig.expo.android.package
    }

    // fallback to slug or name
    if (appConfig.expo?.slug) {
      return appConfig.expo.slug
    }

    if (appConfig.expo?.name) {
      return appConfig.expo.name.toLowerCase().replace(/\s+/g, '-')
    }

    if (appConfig.name) {
      return appConfig.name.toLowerCase().replace(/\s+/g, '-')
    }

    return undefined
  } catch {
    return undefined
  }
}

const MAX_PORT = 65535

export function getAvailablePort(
  preferredPort: number,
  excludePort?: number
): Promise<number> {
  return new Promise((resolve, reject) => {
    import('node:net').then((netModule) => {
      const tryPort = (port: number) => {
        if (port > MAX_PORT) {
          reject(
            new Error(`No available port found between ${preferredPort} and ${MAX_PORT}`)
          )
          return
        }

        if (port === excludePort) {
          tryPort(port + 1)
          return
        }

        // create fresh server for each attempt
        const server = netModule.createServer()

        server.once('error', () => {
          server.close()
          tryPort(port + 1)
        })

        server.once('listening', () => {
          server.close(() => {
            resolve(port)
          })
        })

        server.listen(port, '0.0.0.0')
      }

      tryPort(preferredPort)
    })
  })
}