Refactor setting module and add tests (#4)

Using [golines](https://github.com/segmentio/golines):
`golines -w .`

Makefile

@@ -22,8 +22,14 @@ install-tools:
 	@command $(GOPATH)/shadow > /dev/null 2>&1; if [ $$? -ne 0 ]; then \
 		go install golang.org/x/tools/go/analysis/passes/shadow/cmd/shadow@v0.1.7; \
 	fi
+
+	@command $(GOPATH)/golines > /dev/null 2>&1; if [ $$? -ne 0 ]; then \
+		go install github.com/segmentio/golines@latest; \
+	fi
 .PHONY: lint
 lint: install-tools
+	gofmt -l . && test -z $$(gofmt -l .)
+	golines -l . && test -z $$(golines -l .)
 	golangci-lint run
 	shadow ./...
 

README.md

@@ -7,7 +7,7 @@
   - [Usage](#usage)
   - [Examples](#examples)
     - [Run a default TCP server](#run-a-default-tcp-server)
-    - [Run a TLS server only](#run-a-tls-server-only)
+    - [Run a TLS (HTTP/2) server only](#run-a-tls-http2-server-only)
     - [Run a default TCP server with a custom template and trust a custom header set by an upstream proxy](#run-a-default-tcp-server-with-a-custom-template-and-trust-a-custom-header-set-by-an-upstream-proxy)
   - [Download](#download)
   - [Docker](#docker)
@@ -30,7 +30,7 @@ curl -6 ifconfig.es
 
 ## Features
 
-- TLS is avaliable.
+- TLS and HTTP/2.
 - Can run behind a proxy by trusting a custom header (usually `X-Real-IP`) to figure out the source IP address.
 - IPv4 and IPv6.
 - Geolocation info including ASN. This feature is possible thanks to [maxmind](https://dev.maxmind.com/geoip/geolite2-free-geolocation-data?lang=en) GeoLite2 databases. In order to use these databases, a license key is needed. Please visit Maxmind site for further instructions and get a free license.
@@ -96,7 +96,7 @@ Usage of ./whatismyip:
 ./whatismyip -geoip2-city ./test/GeoIP2-City-Test.mmdb -geoip2-asn ./test/GeoLite2-ASN-Test.mmdb
 ```
 
-### Run a TLS server only
+### Run a TLS (HTTP/2) server only
 
 ```bash
 ./whatismyip -geoip2-city ./test/GeoIP2-City-Test.mmdb -geoip2-asn ./test/GeoLite2-ASN-Test.mmdb -bind "" -tls-bind :8081 -tls-crt ./test/server.pem -tls-key ./test/server.key

cmd/whatismyip.go

@@ -3,6 +3,8 @@ package main
 import (
 	"context"
 	"errors"
+	"flag"
+	"fmt"
 	"log"
 	"net/http"
 	"os"
@@ -24,7 +26,15 @@ var (
 )
 
 func main() {
-	setting.Setup()
+	o, err := setting.Setup(os.Args[1:])
+	if err == flag.ErrHelp || err == setting.ErrVersion {
+		fmt.Print(o)
+		os.Exit(0)
+	} else if err != nil {
+		fmt.Print(err)
+		os.Exit(1)
+	}
+
 	models.Setup(setting.App.GeodbPath.City, setting.App.GeodbPath.ASN)
 	setupEngine()
 	router.SetupTemplate(engine)
@@ -112,7 +122,8 @@ func runTLSServer() {
 
 	go func() {
 		log.Printf("Starting TLS server listening on %s", setting.App.TLSAddress)
-		if err := tlsServer.ListenAndServeTLS(setting.App.TLSCrtPath, setting.App.TLSKeyPath); err != nil && !errors.Is(err, http.ErrServerClosed) {
+		if err := tlsServer.ListenAndServeTLS(setting.App.TLSCrtPath, setting.App.TLSKeyPath); err != nil &&
+			!errors.Is(err, http.ErrServerClosed) {
 			log.Fatal(err)
 		}
 		log.Printf("Stopping TLS server...")

internal/setting/app.go

@@ -1,6 +1,8 @@
 package setting
 
 import (
+	"bytes"
+	"errors"
 	"flag"
 	"fmt"
 	"os"
@@ -26,62 +28,75 @@ type settings struct {
 	TLSKeyPath    string
 	TrustedHeader string
 	Server        serverSettings
+	version       bool
 }
 
 const defaultAddress = ":8080"
 
-var App *settings
+var ErrVersion = errors.New("setting: version requested")
+var App = settings{
+	// hard-coded for the time being
+	Server: serverSettings{
+		ReadTimeout:  10 * time.Second,
+		WriteTimeout: 10 * time.Second,
+	},
+}
 
-func Setup() {
-	city := flag.String("geoip2-city", "", "Path to GeoIP2 city database")
-	asn := flag.String("geoip2-asn", "", "Path to GeoIP2 ASN database")
-	template := flag.String("template", "", "Path to template file")
-	address := flag.String("bind", defaultAddress, "Listening address (see https://pkg.go.dev/net?#Listen)")
-	addressTLS := flag.String("tls-bind", "", "Listening address for TLS (see https://pkg.go.dev/net?#Listen)")
-	tlsCrtPath := flag.String("tls-crt", "", "When using TLS, path to certificate file")
-	tlsKeyPath := flag.String("tls-key", "", "When using TLS, path to private key file")
-	trustedHeader := flag.String("trusted-header", "", "Trusted request header for remote IP (e.g. X-Real-IP)")
-	ver := flag.Bool("version", false, "Output version information and exit")
+func Setup(args []string) (output string, err error) {
+	flags := flag.NewFlagSet("whatismyip", flag.ContinueOnError)
+	var buf bytes.Buffer
+	flags.SetOutput(&buf)
 
-	flag.Parse()
+	flags.StringVar(&App.GeodbPath.City, "geoip2-city", "", "Path to GeoIP2 city database")
+	flags.StringVar(&App.GeodbPath.ASN, "geoip2-asn", "", "Path to GeoIP2 ASN database")
+	flags.StringVar(&App.TemplatePath, "template", "", "Path to template file")
+	flags.StringVar(
+		&App.BindAddress,
+		"bind",
+		defaultAddress,
+		"Listening address (see https://pkg.go.dev/net?#Listen)",
+	)
+	flags.StringVar(
+		&App.TLSAddress,
+		"tls-bind",
+		"",
+		"Listening address for TLS (see https://pkg.go.dev/net?#Listen)",
+	)
+	flags.StringVar(&App.TLSCrtPath, "tls-crt", "", "When using TLS, path to certificate file")
+	flags.StringVar(&App.TLSKeyPath, "tls-key", "", "When using TLS, path to private key file")
+	flags.StringVar(&App.TrustedHeader,
+		"trusted-header",
+		"",
+		"Trusted request header for remote IP (e.g. X-Real-IP)",
+	)
+	flags.BoolVar(&App.version, "version", false, "Output version information and exit")
 
-	if *ver {
-		fmt.Printf("whatismyip version %s", core.Version)
-		os.Exit(0)
+	err = flags.Parse(args)
+	if err != nil {
+		return buf.String(), err
 	}
 
-	if *city == "" || *asn == "" {
-		exitWithError("geoip2-city and geoip2-asn parameters are mandatory")
+	if App.version {
+		return fmt.Sprintf("whatismyip version %s", core.Version), ErrVersion
 	}
 
-	if (*addressTLS != "") && (*tlsCrtPath == "" || *tlsKeyPath == "") {
-		exitWithError("In order to use TLS -tls-crt and -tls-key flags are mandatory")
+	if App.GeodbPath.City == "" || App.GeodbPath.ASN == "" {
+		return "", fmt.Errorf("geoip2-city and geoip2-asn parameters are mandatory")
 	}
 
-	if *template != "" {
-		info, err := os.Stat(*template)
-		if os.IsNotExist(err) || info.IsDir() {
-			exitWithError(*template + " doesn't exist or it's not a file")
+	if (App.TLSAddress != "") && (App.TLSCrtPath == "" || App.TLSKeyPath == "") {
+		return "", fmt.Errorf("In order to use TLS -tls-crt and -tls-key flags are mandatory")
+	}
+
+	if App.TemplatePath != "" {
+		info, err := os.Stat(App.TemplatePath)
+		if os.IsNotExist(err) {
+			return "", fmt.Errorf("%s no such file or directory", App.TemplatePath)
+		}
+		if info.IsDir() {
+			return "", fmt.Errorf("%s must be a file", App.TemplatePath)
 		}
 	}
 
-	App = &settings{
-		GeodbPath:     geodbPath{City: *city, ASN: *asn},
-		TemplatePath:  *template,
-		BindAddress:   *address,
-		TLSAddress:    *addressTLS,
-		TLSCrtPath:    *tlsCrtPath,
-		TLSKeyPath:    *tlsKeyPath,
-		TrustedHeader: *trustedHeader,
-		Server: serverSettings{
-			ReadTimeout:  10 * time.Second,
-			WriteTimeout: 10 * time.Second,
-		},
-	}
-}
-
-func exitWithError(error string) {
-	fmt.Printf("%s\n\n", error)
-	flag.Usage()
-	os.Exit(1)
+	return buf.String(), nil
 }

internal/setting/app_test.go

@@ -0,0 +1,193 @@
+package setting
+
+import (
+	"flag"
+	"reflect"
+	"strings"
+	"testing"
+	"time"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func TestParseMandatoryFlags(t *testing.T) {
+	var mandatoryFlags = []struct {
+		args []string
+		conf settings
+	}{
+		{
+			[]string{},
+			settings{},
+		},
+		{
+			[]string{"-geoip2-city", "/city-path"},
+			settings{},
+		},
+		{
+			[]string{"-geoip2-asn", "/asn-path"},
+			settings{},
+		},
+		{
+			[]string{
+				"-geoip2-city", "/city-path", "-geoip2-asn", "/asn-path", "-tls-bind", ":9000",
+			},
+			settings{},
+		},
+		{
+			[]string{
+				"-geoip2-city", "/city-path", "-geoip2-asn", "/asn-path", "-tls-bind", ":9000",
+				"-tls-crt", "/crt-path",
+			},
+			settings{},
+		},
+		{
+			[]string{
+				"-geoip2-city", "/city-path", "-geoip2-asn", "/asn-path", "-tls-bind", ":9000",
+				"-tls-key", "/key-path",
+			},
+			settings{},
+		},
+	}
+
+	for _, tt := range mandatoryFlags {
+		t.Run(strings.Join(tt.args, " "), func(t *testing.T) {
+			_, err := Setup(tt.args)
+			assert.NotNil(t, err)
+			assert.Contains(t, err.Error(), "mandatory")
+		})
+	}
+}
+
+func TestParseFlags(t *testing.T) {
+	var flags = []struct {
+		args []string
+		conf settings
+	}{
+		{
+			[]string{"-geoip2-city", "/city-path", "-geoip2-asn", "/asn-path"},
+			settings{
+				GeodbPath: geodbPath{
+					City: "/city-path",
+					ASN:  "/asn-path",
+				},
+				TemplatePath:  "",
+				BindAddress:   ":8080",
+				TLSAddress:    "",
+				TLSCrtPath:    "",
+				TLSKeyPath:    "",
+				TrustedHeader: "",
+				Server: serverSettings{
+					ReadTimeout:  10 * time.Second,
+					WriteTimeout: 10 * time.Second,
+				},
+			},
+		},
+		{
+			[]string{"-bind", ":8001", "-geoip2-city", "/city-path", "-geoip2-asn", "/asn-path"},
+			settings{
+				GeodbPath: geodbPath{
+					City: "/city-path",
+					ASN:  "/asn-path",
+				},
+				TemplatePath:  "",
+				BindAddress:   ":8001",
+				TLSAddress:    "",
+				TLSCrtPath:    "",
+				TLSKeyPath:    "",
+				TrustedHeader: "",
+				Server: serverSettings{
+					ReadTimeout:  10 * time.Second,
+					WriteTimeout: 10 * time.Second,
+				},
+			},
+		},
+		{
+			[]string{
+				"-geoip2-city", "/city-path", "-geoip2-asn", "/asn-path", "-tls-bind", ":9000",
+				"-tls-crt", "/crt-path", "-tls-key", "/key-path",
+			},
+			settings{
+				GeodbPath: geodbPath{
+					City: "/city-path",
+					ASN:  "/asn-path",
+				},
+				TemplatePath:  "",
+				BindAddress:   ":8080",
+				TLSAddress:    ":9000",
+				TLSCrtPath:    "/crt-path",
+				TLSKeyPath:    "/key-path",
+				TrustedHeader: "",
+				Server: serverSettings{
+					ReadTimeout:  10 * time.Second,
+					WriteTimeout: 10 * time.Second,
+				},
+			},
+		},
+		{
+			[]string{
+				"-geoip2-city", "/city-path", "-geoip2-asn", "/asn-path",
+				"-trusted-header", "header",
+			},
+			settings{
+				GeodbPath: geodbPath{
+					City: "/city-path",
+					ASN:  "/asn-path",
+				},
+				TemplatePath:  "",
+				BindAddress:   ":8080",
+				TLSAddress:    "",
+				TLSCrtPath:    "",
+				TLSKeyPath:    "",
+				TrustedHeader: "header",
+				Server: serverSettings{
+					ReadTimeout:  10 * time.Second,
+					WriteTimeout: 10 * time.Second,
+				},
+			},
+		},
+	}
+
+	for _, tt := range flags {
+		t.Run(strings.Join(tt.args, " "), func(t *testing.T) {
+			_, err := Setup(tt.args)
+			assert.Nil(t, err)
+			assert.True(t, reflect.DeepEqual(App, tt.conf))
+		})
+	}
+}
+
+func TestParseFlagsUsage(t *testing.T) {
+	var usageArgs = []string{"-help", "-h", "--help"}
+
+	for _, arg := range usageArgs {
+		t.Run(arg, func(t *testing.T) {
+			output, err := Setup([]string{arg})
+			assert.ErrorIs(t, err, flag.ErrHelp)
+			assert.Contains(t, output, "Usage of")
+		})
+	}
+}
+
+func TestParseFlagVersion(t *testing.T) {
+	output, err := Setup([]string{"-version"})
+	assert.ErrorIs(t, err, ErrVersion)
+	assert.Contains(t, output, "whatismyip version")
+}
+
+func TestParseFlagTemplate(t *testing.T) {
+	flags := []string{
+		"-geoip2-city", "/city-path", "-geoip2-asn", "/asn-path",
+		"-template", "/template-path",
+	}
+	_, err := Setup(flags)
+	assert.Error(t, err)
+	assert.Contains(t, err.Error(), "no such file or directory")
+
+	flags = []string{
+		"-geoip2-city", "/city-path", "-geoip2-asn", "/asn-path",
+		"-template", "/",
+	}
+	_, err = Setup(flags)
+	assert.Error(t, err)
+	assert.Contains(t, err.Error(), "must be a file")
+}

router/generic.go

@@ -5,7 +5,6 @@ import (
 	"net/http"
 	"path/filepath"
 	"regexp"
-	"strings"
 
 	"github.com/dcarrillo/whatismyip/internal/httputils"
 	"github.com/dcarrillo/whatismyip/internal/setting"
@@ -46,12 +45,14 @@ func getRoot(ctx *gin.Context) {
 }
 
 func getClientPortAsString(ctx *gin.Context) {
-	ctx.String(http.StatusOK, strings.Split(ctx.Request.RemoteAddr, ":")[1]+"\n")
+	_, port, _ := net.SplitHostPort(ctx.Request.RemoteAddr)
+	ctx.String(http.StatusOK, port+"\n")
 }
 
 func getAllAsString(ctx *gin.Context) {
 	output := "IP: " + ctx.ClientIP() + "\n"
-	output += "Client Port: " + strings.Split(ctx.Request.RemoteAddr, ":")[1] + "\n"
+	_, port, _ := net.SplitHostPort(ctx.Request.RemoteAddr)
+	output += "Client Port: " + port + "\n"
 
 	r := service.Geo{IP: net.ParseIP(ctx.ClientIP())}
 	if record := r.LookUpCity(); record != nil {
@@ -82,10 +83,11 @@ func jsonOutput(ctx *gin.Context) JSONResponse {
 		version = 6
 	}
 
+	_, port, _ := net.SplitHostPort(ctx.Request.RemoteAddr)
 	return JSONResponse{
 		IP:              ctx.ClientIP(),
 		IPVersion:       version,
-		ClientPort:      strings.Split(ctx.Request.RemoteAddr, ":")[1],
+		ClientPort:      port,
 		Country:         cityRecord.Country.Names["en"],
 		CountryCode:     cityRecord.Country.ISOCode,
 		City:            cityRecord.City.Names["en"],

router/generic_test.go

@@ -1,6 +1,7 @@
 package router
 
 import (
+	"net"
 	"net/http"
 	"net/http/httptest"
 	"testing"
@@ -9,7 +10,18 @@ import (
 )
 
 func TestIP4RootFromCli(t *testing.T) {
-	uas := []string{"", "curl", "wget", "libwww-perl", "python", "ansible-httpget", "HTTPie", "WindowsPowerShell", "http_request", "Go-http-client"}
+	uas := []string{
+		"",
+		"curl",
+		"wget",
+		"libwww-perl",
+		"python",
+		"ansible-httpget",
+		"HTTPie",
+		"WindowsPowerShell",
+		"http_request",
+		"Go-http-client",
+	}
 
 	req, _ := http.NewRequest("GET", "/", nil)
 	req.Header.Set("X-Real-IP", testIP.ipv4)
@@ -37,7 +49,7 @@ func TestHost(t *testing.T) {
 
 func TestClientPort(t *testing.T) {
 	req, _ := http.NewRequest("GET", "/client-port", nil)
-	req.RemoteAddr = testIP.ipv4 + ":" + "1000"
+	req.RemoteAddr = net.JoinHostPort(testIP.ipv4, "1000")
 	req.Header.Set("X-Real-IP", testIP.ipv4)
 
 	w := httptest.NewRecorder()
@@ -60,10 +72,10 @@ func TestNotFound(t *testing.T) {
 
 func TestJSON(t *testing.T) {
 	expectedIPv4 := `{"client_port":"1000","ip":"81.2.69.192","ip_version":4,"country":"United Kingdom","country_code":"GB","city":"London","latitude":51.5142,"longitude":-0.0931,"postal_code":"","time_zone":"Europe/London","asn":0,"asn_organization":"","host":"test","headers":{"X-Real-Ip":["81.2.69.192"]}}`
-	expectedIPv6 := `{"asn":3352, "asn_organization":"TELEFONICA DE ESPANA", "city":"", "client_port":"9000", "country":"", "country_code":"", "headers":{"X-Real-Ip":["2a02:9000::1"]}, "host":"test", "ip":"2a02:9000::1", "ip_version":6, "latitude":0, "longitude":0, "postal_code":"", "time_zone":""}`
+	expectedIPv6 := `{"asn":3352, "asn_organization":"TELEFONICA DE ESPANA", "city":"", "client_port":"1000", "country":"", "country_code":"", "headers":{"X-Real-Ip":["2a02:9000::1"]}, "host":"test", "ip":"2a02:9000::1", "ip_version":6, "latitude":0, "longitude":0, "postal_code":"", "time_zone":""}`
 
 	req, _ := http.NewRequest("GET", "/json", nil)
-	req.RemoteAddr = testIP.ipv4 + ":" + "1000"
+	req.RemoteAddr = net.JoinHostPort(testIP.ipv4, "1000")
 	req.Host = "test"
 	req.Header.Set("X-Real-IP", testIP.ipv4)
 
@@ -74,7 +86,7 @@ func TestJSON(t *testing.T) {
 	assert.Equal(t, contentType.json, w.Header().Get("Content-Type"))
 	assert.JSONEq(t, expectedIPv4, w.Body.String())
 
-	req.RemoteAddr = testIP.ipv6 + ":" + "1000"
+	req.RemoteAddr = net.JoinHostPort(testIP.ipv6, "1000")
 	req.Host = "test"
 	req.Header.Set("X-Real-IP", testIP.ipv6)
 
@@ -106,7 +118,7 @@ X-Real-Ip: 81.2.69.192
 `
 
 	req, _ := http.NewRequest("GET", "/all", nil)
-	req.RemoteAddr = testIP.ipv4 + ":" + "1000"
+	req.RemoteAddr = net.JoinHostPort(testIP.ipv4, "1000")
 	req.Host = "test"
 	req.Header.Set("X-Real-IP", testIP.ipv4)
 	req.Header.Set("Header1", "one")