Function findAvailablePort

src/services/mcp/oauthPort.ts:36–78

()

 * Uses random selection for better security
 */
export async function findAvailablePort(): Promise<number> {
  // First, try the configured port if specified
  const configuredPort = getMcpOAuthCallbackPort()
  if (configuredPort) {
    return configuredPort
  }

  const { min, max } = REDIRECT_PORT_RANGE
  const range = max - min + 1
  const maxAttempts = Math.min(range, 100) // Don't try forever

  for (let attempt = 0; attempt < maxAttempts; attempt++) {
    const port = min + Math.floor(Math.random() * range)

    try {
      await new Promise<void>((resolve, reject) => {
        const testServer = createServer()
        testServer.once('error', reject)
        testServer.listen(port, () => {
          testServer.close(() => resolve())
        })
      })
      return port
    } catch {
      // Port in use, try another random port
      continue
    }
  }

  // If random selection failed, try the fallback port
  try {
    await new Promise<void>((resolve, reject) => {
      const testServer = createServer()
      testServer.once('error', reject)
      testServer.listen(REDIRECT_PORT_FALLBACK, () => {
        testServer.close(() => resolve())
      })
    })
    return REDIRECT_PORT_FALLBACK
  } catch {
    throw new Error(`No available ports for OAuth redirect`)
  }
}