refactor imageproxy-sign to make testing easier

cmd/imageproxy-sign/main.go

@@ -6,6 +6,7 @@ import (
 	"crypto/hmac"
 	"crypto/sha256"
 	"encoding/base64"
+	"errors"
 	"flag"
 	"fmt"
 	"io/ioutil"
@@ -17,38 +18,44 @@ import (
 	"willnorris.com/go/imageproxy"
 )
 
-var key = flag.String("key", "@/etc/imageproxy.key", "signing key, or file containing key prefixed with '@'")
+var signingKey = flag.String("key", "@/etc/imageproxy.key", "signing key, or file containing key prefixed with '@'")
 var urlOnly = flag.Bool("url", false, "only sign the URL value, do not include options")
 
 func main() {
 	flag.Parse()
+	u := flag.Arg(0)
 
-	if flag.NArg() < 1 {
-		fmt.Println("imageproxy-sign url [key]")
+	sig, err := sign(*signingKey, u, *urlOnly)
+	if err != nil {
+		fmt.Println(err)
 		os.Exit(1)
 	}
 
-	u := parseURL(flag.Arg(0))
+	fmt.Printf("url: %v\n", u)
+	fmt.Printf("signature: %v\n", base64.URLEncoding.EncodeToString(sig))
+}
+
+func sign(key string, s string, urlOnly bool) ([]byte, error) {
+	if s == "" {
+		return nil, errors.New("imageproxy-sign url [key]")
+	}
+
+	u := parseURL(s)
 	if u == nil {
-		fmt.Printf("unable to parse URL: %v\n", flag.Arg(0))
-		os.Exit(1)
+		return nil, fmt.Errorf("unable to parse URL: %v", s)
 	}
-	if *urlOnly {
+	if urlOnly {
 		u.Fragment = ""
 	}
 
-	k, err := parseKey(*key)
+	k, err := parseKey(key)
 	if err != nil {
-		fmt.Printf("error parsing key: %v", err)
-		os.Exit(1)
+		return nil, fmt.Errorf("error parsing key: %v", err)
 	}
 
 	mac := hmac.New(sha256.New, []byte(k))
 	mac.Write([]byte(u.String()))
-	sig := mac.Sum(nil)
-
-	fmt.Printf("url: %v\n", u)
-	fmt.Printf("signature: %v\n", base64.URLEncoding.EncodeToString(sig))
+	return mac.Sum(nil), nil
 }
 
 func parseKey(s string) ([]byte, error) {

cmd/imageproxy-sign/main_test.go

@@ -1,10 +1,76 @@
 package main
 
 import (
+	"io/ioutil"
 	"net/url"
+	"os"
+	"reflect"
 	"testing"
 )
 
+var key = "secret"
+
+func TestSign(t *testing.T) {
+	s := "http://example.com/image.jpg#0x0"
+
+	got, err := sign(key, s, false)
+	if err != nil {
+		t.Errorf("sign(%q, %q, false) returned error: %v", key, s, err)
+	}
+	want := []byte{0xc3, 0x4c, 0x45, 0xb5, 0x75, 0x84, 0x76, 0xdf, 0xd9, 0x6b, 0x12, 0xa4, 0x84, 0x8f, 0x37, 0xc6, 0x2d, 0x8b, 0x8d, 0x77, 0xda, 0x6, 0xf8, 0xb5, 0x10, 0xc9, 0x96, 0x3c, 0x6e, 0x13, 0xda, 0xf0}
+	if !reflect.DeepEqual(got, want) {
+		t.Errorf("sign(%q, %q, true) returned %v, want %v", key, s, got, want)
+	}
+}
+
+func TestSign_URLOnly(t *testing.T) {
+	s := "http://example.com/image.jpg#0x0"
+
+	got, err := sign(key, s, true)
+	if err != nil {
+		t.Errorf("sign(%q, %q, true) returned error: %v", key, s, err)
+	}
+	want := []byte{0x93, 0xea, 0x5d, 0x23, 0x68, 0xa0, 0xfc, 0x50, 0x8e, 0x91, 0x7, 0xbf, 0x3e, 0xb3, 0x1f, 0x49, 0xf7, 0x1d, 0x81, 0xf1, 0x74, 0xfe, 0x25, 0x36, 0xfc, 0x74, 0xf8, 0x81, 0x15, 0xf5, 0x58, 0x40}
+	if !reflect.DeepEqual(got, want) {
+		t.Errorf("sign(%q, %q, true) returned %v, want %v", key, s, got, want)
+	}
+}
+
+func TestParseKey(t *testing.T) {
+	k, err := parseKey(key)
+	got := string(k)
+	if err != nil {
+		t.Errorf("parseKey(%q) returned error: %v", key, err)
+	}
+	if want := key; got != want {
+		t.Errorf("parseKey(%q) returned %v, want %v", key, got, want)
+	}
+}
+
+func TestParseKey_FilePath(t *testing.T) {
+	f, err := ioutil.TempFile("", "key")
+	if err != nil {
+		t.Errorf("error creating temp file: %v", err)
+	}
+	defer func() {
+		f.Close()
+		os.Remove(f.Name())
+	}()
+
+	if _, err := f.WriteString(key); err != nil {
+		t.Errorf("error writing to temp file: %v", err)
+	}
+	path := "@" + f.Name()
+	k, err := parseKey(path)
+	got := string(k)
+	if err != nil {
+		t.Errorf("parseKey(%q) returned error: %v", path, err)
+	}
+	if want := key; got != want {
+		t.Errorf("parseKey(%q) returned %v, want %v", path, got, want)
+	}
+}
+
 func TestParseURL(t *testing.T) {
 	tests := []struct {
 		input, output string