diff options
| -rw-r--r-- | icanhazallips.go | 153 |
1 files changed, 137 insertions, 16 deletions
diff --git a/icanhazallips.go b/icanhazallips.go index 68a2f82..684fea8 100644 --- a/icanhazallips.go +++ b/icanhazallips.go @@ -2,19 +2,43 @@ package main import ( + "crypto/tls" "errors" - "fmt" "log" "net" "net/http" + "os" + "strconv" "strings" + "time" ) -func getIP(r *http.Request) (string, error) { - ips := r.Header.Get("X-Forwarded-For") +const ( + defaultTimeOut = 10. +) + +var ( + errMalformedAdr = errors.New("malformed address") + errIPNotFound = errors.New("ip not found") + errBadFloatValue = errors.New("bad float value") + errBadConfig = errors.New("bad config") +) + +func getDefaultOptions() map[string]float64 { + return map[string]float64{ + "APP_CONTEXT_TIMEOUT": defaultTimeOut, + "APP_READ_HEADER_TIMEOUT": defaultTimeOut, + "APP_READ_TIMEOUT": defaultTimeOut, + "APP_WRITE_TIMEOUT": defaultTimeOut, + "APP_IDLE_TIMEOUT": defaultTimeOut, + } +} + +func getIP(request *http.Request) (string, error) { + ips := request.Header.Get("X-Forwarded-For") splitIps := strings.Split(ips, ",") - fmt.Println(r.RemoteAddr) + log.Println(request.RemoteAddr) if len(splitIps) > 0 { netIP := net.ParseIP(splitIps[len(splitIps)-1]) @@ -23,35 +47,132 @@ func getIP(r *http.Request) (string, error) { } } - ip, _, err := net.SplitHostPort(r.RemoteAddr) + ip, _, err := net.SplitHostPort(request.RemoteAddr) if err != nil { - return "", err + return "", errMalformedAdr } - netIP := net.ParseIP(ip) - if netIP != nil { + if netIP := net.ParseIP(ip); netIP != nil { ip := netIP.String() if ip == "::1" { return "127.0.0.1", nil } + return ip, nil } - return "", errors.New("IP not found") + return "", errIPNotFound } -func handler(w http.ResponseWriter, r *http.Request) { - ip, err := getIP(r) +func ipHandler(writer http.ResponseWriter, request *http.Request) { + ipAddr, err := getIP(request) if err != nil { - w.WriteHeader(http.StatusInternalServerError) + writer.WriteHeader(http.StatusInternalServerError) + + return + } + + writer.WriteHeader(http.StatusOK) + + writtenLen, err := writer.Write([]byte(ipAddr)) + if err != nil || writtenLen != len(ipAddr) { + writer.WriteHeader(http.StatusInternalServerError) + return } +} - w.WriteHeader(http.StatusOK) - w.Write([]byte(ip)) +type Config struct { + Addr string + ContextTimeOut float64 + ReadHeaderTimeout float64 + ReadTimeout float64 + WriteTimeout float64 + IdleTimeout float64 +} + +func getConfigValue(envVarName string) (float64, error) { + defaultOptions := getDefaultOptions() + + paramEnv := os.Getenv(envVarName) + if paramEnv != "" { + param, err := strconv.ParseFloat(paramEnv, 64) + if err != nil { + return defaultOptions[envVarName], errBadFloatValue + } + + return param, nil + } + + return defaultOptions[envVarName], nil +} + +func getConfig() (Config, error) { + var config Config + + var err error + + appAddrEnv := os.Getenv("APP_ADDR") + if appAddrEnv != "" { + config.Addr = appAddrEnv + } else { + config.Addr = ":8080" + } + + config.ContextTimeOut, err = getConfigValue("APP_CONTEXT_TIMEOUT") + if err != nil { + log.Println(err.Error()) + } + + config.ReadHeaderTimeout, err = getConfigValue("APP_READ_HEADER_TIMEOUT") + if err != nil { + log.Println(err.Error()) + } + + config.ReadTimeout, err = getConfigValue("APP_READ_TIMEOUT") + if err != nil { + log.Println(err.Error()) + } + + config.WriteTimeout, err = getConfigValue("APP_WRITE_TIMEOUT") + if err != nil { + log.Println(err.Error()) + } + + config.IdleTimeout, err = getConfigValue("APP_IDLE_TIMEOUT") + if err != nil { + log.Println(err.Error()) + } + + return config, err } func main() { - http.HandleFunc("/", handler) - log.Fatal(http.ListenAndServeTLS(":8080", "/certs/server.cert", "/certs/server.key", nil)) + log.SetOutput(os.Stdout) + http.HandleFunc("/", ipHandler) + + config, err := getConfig() + if err != nil { + log.Fatal(errBadConfig) + } + + tlsConfig := &tls.Config{ + MinVersion: tls.VersionTLS13, + CurvePreferences: []tls.CurveID{tls.CurveP521, tls.CurveP384, tls.CurveP256}, + PreferServerCipherSuites: true, + } + + server := http.Server{ + Addr: config.Addr, + ReadHeaderTimeout: time.Duration(config.ReadHeaderTimeout) * time.Second, + ReadTimeout: time.Duration(config.ReadTimeout) * time.Second, + WriteTimeout: time.Duration(config.WriteTimeout) * time.Second, + IdleTimeout: time.Duration(config.IdleTimeout) * time.Second, + TLSNextProto: nil, + ErrorLog: nil, + Handler: nil, + TLSConfig: tlsConfig, + } + + log.Fatal(server.ListenAndServeTLS("/certs/server.cert", "/certs/server.key")) } |