Dns Laravel Package

Getting Started

1. Install the package via Composer:

   composer require amphp/dns
   

2. Ensure Amp is installed — amphp/dns depends on amphp/amp and amphp/socket, so the event loop is automatically bootstrapped if using Amp’s standard async stack.
3. First use case — resolve a simple A record:

   use Amp\Dns;
   
   require 'vendor/autoload.php';
   
   $address = Dns\resolve('example.com', Dns\Record::A);
   echo $address; // e.g., "93.184.216.34"
   

4. Start with the API docs — focus on Dns\resolve(), Dns\resolveOne(), and Dns\query() methods.

Implementation Patterns

• Batch lookups with query() for efficiency:

  $records = Dns\query('example.com', Dns\Record::MX | Dns\Record::TXT);
  

• Custom resolvers via ResolverFactory or BootstrapResolver for environments with custom DNS (e.g., Docker, internal networks):

  $resolver = (new Dns\BootstrapResolverFactory())->create(['8.8.8.8', '1.1.1.1']);
  $ip = Dns\resolve('example.com', Dns\Record::A, $resolver);
  

• Integrate into async network clients (e.g., HTTP clients, TCP servers):
  Perform DNS resolution before connecting to avoid blocking on connection errors or timeouts.
• Caching optimization:
  Built-in TTL-based caching is automatic, but you can disable it via ResolverConfig for ephemeral lookups.

Gotchas and Tips

• Exception handling is critical — DNS failures throw Dns\Exception\DnsException or Dns\Exception\TimeoutException. Always wrap resolve() in try/catch or use Promise\timeout().
• DNS resolution is not guaranteed synchronous — even resolve() returns a Promise. Use Amp\Promise\wait() only in CLI scripts or tests; in web apps, keep async end-to-end.
• Caching quirks:
  • Resolver-level cache is per-resolver instance, not global. Reuse resolvers in long-lived processes.
  • Negative caching (e.g., NXDOMAIN) follows RFC standards (SOA minimum TTL), which may be longer than expected.
• Extension points:
  • Override cache TTLs via ResolverConfig::setTtl().
  • Provide custom DNS servers or fallback logic using Dns\ServerParser.
• Debugging tip: Use Dns\getHosts() to inspect local /etc/hosts entries for debugging precedence vs. upstream DNS.