package net import ( "errors" "fmt" "net" "os" "strconv" "strings" ) // HostPort format addr and port suitable for dial func HostPort(addr string, port interface{}) string { host := addr if strings.Count(addr, ":") > 0 { host = fmt.Sprintf("[%s]", addr) } // when port is blank or 0, host is a queue name if v, ok := port.(string); ok && v == "" { return host } else if v, ok := port.(int); ok && v == 0 && net.ParseIP(host) == nil { return host } return fmt.Sprintf("%s:%v", host, port) } // Listen takes addr:portmin-portmax and binds to the first available port // Example: Listen("localhost:5000-6000", fn) func Listen(addr string, fn func(string) (net.Listener, error)) (net.Listener, error) { if strings.Count(addr, ":") == 1 && strings.Count(addr, "-") == 0 { return fn(addr) } // host:port || host:min-max host, ports, err := net.SplitHostPort(addr) if err != nil { return nil, err } // try to extract port range prange := strings.Split(ports, "-") // single port if len(prange) < 2 { return fn(addr) } // we have a port range // extract min port min, err := strconv.Atoi(prange[0]) if err != nil { return nil, errors.New("unable to extract port range") } // extract max port max, err := strconv.Atoi(prange[1]) if err != nil { return nil, errors.New("unable to extract port range") } // range the ports for port := min; port <= max; port++ { // try bind to host:port ln, err := fn(HostPort(host, port)) if err == nil { return ln, nil } // hit max port if port == max { return nil, err } } // why are we here? return nil, fmt.Errorf("unable to bind to %s", addr) } // Proxy returns the proxy and the address if it exits func Proxy(service string, address []string) (string, []string, bool) { var hasProxy bool // get proxy if prx := os.Getenv("MICRO_PROXY"); len(prx) > 0 { // default name if prx == "service" { prx = "go.micro.proxy" } service = prx hasProxy = true } // get proxy address if prx := os.Getenv("MICRO_PROXY_ADDRESS"); len(prx) > 0 { address = []string{prx} hasProxy = true } if prx := os.Getenv("MICRO_NETWORK"); len(prx) > 0 { // default name if prx == "service" { prx = "go.micro.network" } service = prx hasProxy = true } if prx := os.Getenv("MICRO_NETWORK_ADDRESS"); len(prx) > 0 { address = []string{prx} hasProxy = true } return service, address, hasProxy }