netutil

Network utilities: port availability, IP address helpers, HTTP client with retry, and TCP/UDP utilities.

Features

• Port availability: check, find, and allocate free ports (TCP/UDP)
• IP address helpers: local, outbound, public, private/loopback detection
• HTTP client with configurable retry, timeout, and circuit breaker
• TCP/UDP utilities: dial, listen, ping, forward

Key types

• HTTPClientConfig -- HTTP client settings (timeout, max retries, retry interval, circuit breaker)
• CircuitBreakerConfig -- circuit breaker thresholds and cooldown

Key functions

• IsPortAvailable(network, port), IsTCPPortAvailable(port), IsUDPPortAvailable(port)
• FreePort(), FreeUDPPort(), FindAvailablePort(start, end), FindAvailablePorts(start, n)
• LocalIP(), LocalIPs(), LocalIPv6s(), AllIPs(), OutboundIP(target)
• PublicIP(), IsPrivateIP(ipStr), IsLoopback(ipStr), IsPublicIP(ipStr)
• IPRange(cidr) -- start and end IPs of a CIDR range
• NewHTTPClient(cfg) -- HTTP client with retry and circuit breaker
• DialTCP, ListenTCP, Ping, ForwardTCP -- low-level TCP utilities

Quick start

import (
    "time"
    "github.com/LingByte/ling-base/common/netutil"
)

// Check if a port is available
ok := netutil.IsPortAvailable("tcp", 8080)

// Get local IP
ip := netutil.LocalIP()

// HTTP client with retry
client := netutil.NewHTTPClient(netutil.HTTPClientConfig{
    Timeout:       10 * time.Second,
    MaxRetries:    3,
    RetryInterval: time.Second,
})
resp, err := client.Get("https://example.com")

License

MIT