add coverage for cert subcommand

cmd/cert.go

@@ -14,6 +14,7 @@ import (
 	"crypto/x509"
 	"crypto/x509/pkix"
 	"encoding/pem"
+	"fmt"
 	"log"
 	"math/big"
 	"net"
@@ -25,43 +26,55 @@ import (
 )
 
 // CmdCert represents the available cert sub-command.
-var CmdCert = &cli.Command{
+func CmdCert() *cli.Command {
-	Name:  "cert",
+	return &cli.Command{
-	Usage: "Generate self-signed certificate",
+		Name:  "cert",
-	Description: `Generate a self-signed X.509 certificate for a TLS server.
+		Usage: "Generate self-signed certificate",
+		Description: `Generate a self-signed X.509 certificate for a TLS server.
 Outputs to 'cert.pem' and 'key.pem' and will overwrite existing files.`,
-	Action: runCert,
+		Action: runCert,
-	Flags: []cli.Flag{
+		Flags: []cli.Flag{
-		&cli.StringFlag{
+			&cli.StringFlag{
-			Name:  "host",
+				Name:  "host",
-			Value: "",
+				Value: "",
-			Usage: "Comma-separated hostnames and IPs to generate a certificate for",
+				Usage: "Comma-separated hostnames and IPs to generate a certificate for",
+			},
+			&cli.StringFlag{
+				Name:  "ecdsa-curve",
+				Value: "",
+				Usage: "ECDSA curve to use to generate a key. Valid values are P224, P256, P384, P521",
+			},
+			&cli.IntFlag{
+				Name:  "rsa-bits",
+				Value: 3072,
+				Usage: "Size of RSA key to generate. Ignored if --ecdsa-curve is set",
+			},
+			&cli.StringFlag{
+				Name:  "start-date",
+				Value: "",
+				Usage: "Creation date formatted as Jan 1 15:04:05 2011",
+			},
+			&cli.DurationFlag{
+				Name:  "duration",
+				Value: 365 * 24 * time.Hour,
+				Usage: "Duration that certificate is valid for",
+			},
+			&cli.BoolFlag{
+				Name:  "ca",
+				Usage: "whether this cert should be its own Certificate Authority",
+			},
+			&cli.StringFlag{
+				Name:  "out",
+				Value: "cert.pem",
+				Usage: "Path to the file where there certificate will be saved",
+			},
+			&cli.StringFlag{
+				Name:  "keyout",
+				Value: "key.pem",
+				Usage: "Path to the file where there certificate key will be saved",
+			},
 		},
-		&cli.StringFlag{
+	}
-			Name:  "ecdsa-curve",
-			Value: "",
-			Usage: "ECDSA curve to use to generate a key. Valid values are P224, P256, P384, P521",
-		},
-		&cli.IntFlag{
-			Name:  "rsa-bits",
-			Value: 3072,
-			Usage: "Size of RSA key to generate. Ignored if --ecdsa-curve is set",
-		},
-		&cli.StringFlag{
-			Name:  "start-date",
-			Value: "",
-			Usage: "Creation date formatted as Jan 1 15:04:05 2011",
-		},
-		&cli.DurationFlag{
-			Name:  "duration",
-			Value: 365 * 24 * time.Hour,
-			Usage: "Duration that certificate is valid for",
-		},
-		&cli.BoolFlag{
-			Name:  "ca",
-			Usage: "whether this cert should be its own Certificate Authority",
-		},
-	},
 }
 
 func publicKey(priv any) any {
@@ -109,17 +122,19 @@ func runCert(_ context.Context, c *cli.Command) error {
 	case "P521":
 		priv, err = ecdsa.GenerateKey(elliptic.P521(), rand.Reader)
 	default:
-		log.Fatalf("Unrecognized elliptic curve: %q", c.String("ecdsa-curve"))
+		err = fmt.Errorf("Unrecognized elliptic curve: %q", c.String("ecdsa-curve"))
 	}
 	if err != nil {
-		log.Fatalf("Failed to generate private key: %v", err)
+		// log.Fatalf("Failed to generate private key: %v", err)
+		return err
 	}
 
 	var notBefore time.Time
 	if startDate := c.String("start-date"); startDate != "" {
 		notBefore, err = time.Parse("Jan 2 15:04:05 2006", startDate)
 		if err != nil {
-			log.Fatalf("Failed to parse creation date: %v", err)
+			// log.Fatalf("Failed to parse creation date: %v", err)
+			return fmt.Errorf("Failed to parse creation date %w", err)
 		}
 	} else {
 		notBefore = time.Now()
@@ -130,7 +145,8 @@ func runCert(_ context.Context, c *cli.Command) error {
 	serialNumberLimit := new(big.Int).Lsh(big.NewInt(1), 128)
 	serialNumber, err := rand.Int(rand.Reader, serialNumberLimit)
 	if err != nil {
-		log.Fatalf("Failed to generate serial number: %v", err)
+		// log.Fatalf("Failed to generate serial number: %v", err)
+		return err
 	}
 
 	template := x509.Certificate{
@@ -163,34 +179,41 @@ func runCert(_ context.Context, c *cli.Command) error {
 
 	derBytes, err := x509.CreateCertificate(rand.Reader, &template, &template, publicKey(priv), priv)
 	if err != nil {
-		log.Fatalf("Failed to create certificate: %v", err)
+		// log.Fatalf("Failed to create certificate: %v", err)
+		return err
 	}
 
-	certOut, err := os.Create("cert.pem")
+	certOut, err := os.Create(c.String("out"))
 	if err != nil {
-		log.Fatalf("Failed to open cert.pem for writing: %v", err)
+		// log.Fatalf("Failed to open cert.pem for writing: %v", err)
+		return err
 	}
 	err = pem.Encode(certOut, &pem.Block{Type: "CERTIFICATE", Bytes: derBytes})
 	if err != nil {
-		log.Fatalf("Failed to encode certificate: %v", err)
+		// log.Fatalf("Failed to encode certificate: %v", err)
+		return err
 	}
 	err = certOut.Close()
 	if err != nil {
-		log.Fatalf("Failed to write cert: %v", err)
+		// log.Fatalf("Failed to write cert: %v", err)
+		return err
 	}
 	log.Println("Written cert.pem")
 
-	keyOut, err := os.OpenFile("key.pem", os.O_WRONLY|os.O_CREATE|os.O_TRUNC, 0o600)
+	keyOut, err := os.OpenFile(c.String("keyout"), os.O_WRONLY|os.O_CREATE|os.O_TRUNC, 0o600)
 	if err != nil {
-		log.Fatalf("Failed to open key.pem for writing: %v", err)
+		// log.Fatalf("Failed to open key.pem for writing: %v", err)
+		return err
 	}
 	err = pem.Encode(keyOut, pemBlockForKey(priv))
 	if err != nil {
-		log.Fatalf("Failed to encode key: %v", err)
+		// log.Fatalf("Failed to encode key: %v", err)
+		return err
 	}
 	err = keyOut.Close()
 	if err != nil {
-		log.Fatalf("Failed to write key: %v", err)
+		// log.Fatalf("Failed to write key: %v", err)
+		return err
 	}
 	log.Println("Written key.pem")
 	return nil

cmd/cert_test.go

@@ -0,0 +1,125 @@
+// Copyright 2025 The Gitea Authors. All rights reserved.
+// SPDX-License-Identifier: MIT
+
+package cmd
+
+import (
+	"path/filepath"
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+)
+
+func TestCertCommand(t *testing.T) {
+	cases := []struct {
+		name string
+		args []string
+	}{
+		{
+			name: "RSA cert generation",
+			args: []string{
+				"cert-test",
+				"--host", "localhost",
+				"--rsa-bits", "2048",
+				"--duration", "1h",
+				"--start-date", "Jan 1 00:00:00 2024",
+			},
+		},
+		{
+			name: "ECDSA cert generation",
+			args: []string{
+				"cert-test",
+				"--host", "localhost",
+				"--ecdsa-curve", "P256",
+				"--duration", "1h",
+				"--start-date", "Jan 1 00:00:00 2024",
+			},
+		},
+		{
+			name: "mixed host, certificate authority",
+			args: []string{
+				"cert-test",
+				"--host", "localhost,127.0.0.1",
+				"--duration", "1h",
+				"--start-date", "Jan 1 00:00:00 2024",
+			},
+		},
+	}
+
+	for _, c := range cases {
+		t.Run(c.name, func(t *testing.T) {
+			app := CmdCert()
+			tempDir := t.TempDir()
+
+			certFile := filepath.Join(tempDir, "cert.pem")
+			keyFile := filepath.Join(tempDir, "key.pem")
+
+			args := append(c.args, "--out", certFile, "--keyout", keyFile)
+			err := app.Run(t.Context(), args)
+			require.NoError(t, err)
+
+			assert.FileExists(t, certFile)
+			assert.FileExists(t, keyFile)
+		})
+	}
+}
+
+func TestCertCommandFailures(t *testing.T) {
+	cases := []struct {
+		name   string
+		args   []string
+		errMsg string
+	}{
+		{
+			name: "Start Date Parsing failure",
+			args: []string{
+				"cert-test",
+				"--host", "localhost",
+				"--start-date", "invalid-date",
+			},
+			errMsg: "parsing time",
+		},
+		{
+			name: "Unknown curve",
+			args: []string{
+				"cert-test",
+				"--host", "localhost",
+				"--ecdsa-curve", "invalid-curve",
+			},
+			errMsg: "Unrecognized elliptic curve",
+		},
+		{
+			name: "Key generation failure",
+			args: []string{
+				"cert-test",
+				"--host", "localhost",
+				"--rsa-bits", "invalid-bits",
+			},
+		},
+		{
+			name: "Missing parameters",
+			args: []string{
+				"cert-test",
+			},
+			errMsg: "host is not set",
+		},
+	}
+	for _, c := range cases {
+		t.Run(c.name, func(t *testing.T) {
+			app := CmdCert()
+			tempDir := t.TempDir()
+
+			certFile := filepath.Join(tempDir, "cert.pem")
+			keyFile := filepath.Join(tempDir, "key.pem")
+			args := append(c.args, "--out", certFile, "--keyout", keyFile)
+			err := app.Run(t.Context(), args)
+			require.Error(t, err)
+			if c.errMsg != "" {
+				assert.ErrorContains(t, err, c.errMsg)
+			}
+			assert.NoFileExists(t, certFile)
+			assert.NoFileExists(t, keyFile)
+		})
+	}
+}

cmd/main.go

@@ -150,7 +150,7 @@ func NewMainApp(appVer AppVersion) *cli.Command {
 
 	// these sub-commands do not need the config file, and they do not depend on any path or environment variable.
 	subCmdStandalone := []*cli.Command{
-		CmdCert,
+		CmdCert(),
 		CmdGenerate,
 		CmdDocs,
 	}