dial tcp [::1]:PORT: connect: connection refused

Workarounds

1. 95% success Verify the server is running on the expected host:port

   curl -v http://localhost:PORT  # or: ss -tlnp | grep PORT

   Sources: https://pkg.go.dev/net#Dial

2. 88% success Check if using IPv6 [::1] vs IPv4 127.0.0.1 — server may only listen on one

   :1] vs IPv4 127.0.0.1 — server may only listen on one

   Sources: https://pkg.go.dev/net#Dial

3. 82% success Add retry logic with backoff for services that start slowly

   import "time"
   
   func connectWithRetry(addr string, maxRetries int) (net.Conn, error) {
       var conn net.Conn
       var err error
       for i := 0; i < maxRetries; i++ {
           conn, err = net.DialTimeout("tcp", addr, 5*time.Second)
           if err == nil {
               return conn, nil
           }
           time.Sleep(time.Duration(1<<uint(i)) * time.Second)
       }
       return nil, err
   }

   Sources: https://pkg.go.dev/net#Dial