Suppress diff for dns names on custom certificate resources (Fixes: #146).

digitalocean/resource_digitalocean_certificate.go

@@ -60,6 +60,9 @@ func resourceDigitalOceanCertificate() *schema.Resource {
 				Optional:      true,
 				ForceNew:      true,
 				ConflictsWith: []string{"private_key", "leaf_certificate", "certificate_chain"},
+				DiffSuppressFunc: func(k, old, new string, d *schema.ResourceData) bool {
+					return d.Get("type") == "custom"
+				},
 			},
 
 			"type": {

digitalocean/resource_digitalocean_certificate_test.go

@@ -1,10 +1,18 @@
 package digitalocean
 
 import (
+	"bytes"
 	"context"
+	crand "crypto/rand"
+	"crypto/rsa"
+	"crypto/x509"
+	"crypto/x509/pkix"
+	"encoding/pem"
 	"fmt"
+	"math/big"
 	"strings"
 	"testing"
+	"time"
 
 	"github.com/digitalocean/godo"
 	"github.com/hashicorp/terraform/helper/acctest"
@@ -90,11 +98,11 @@ func testAccCheckDigitalOceanCertificateExists(n string, cert *godo.Certificate)
 }
 
 func generateTestCertMaterial(t *testing.T) (string, string, string) {
-	leafCertMaterial, privateKeyMaterial, err := acctest.RandTLSCert("Acme Co")
+	leafCertMaterial, privateKeyMaterial, err := randTLSCert("Acme Co", "example.com")
 	if err != nil {
 		t.Fatalf("Cannot generate test TLS certificate: %s", err)
 	}
-	rootCertMaterial, _, err := acctest.RandTLSCert("Acme Go")
+	rootCertMaterial, _, err := randTLSCert("Acme Go", "example.com")
 	if err != nil {
 		t.Fatalf("Cannot generate test TLS certificate: %s", err)
 	}
@@ -103,6 +111,63 @@ func generateTestCertMaterial(t *testing.T) (string, string, string) {
 	return privateKeyMaterial, leafCertMaterial, certChainMaterial
 }
 
+// Based on Terraform's acctest.RandTLSCert, but allows for passing DNS name.
+func randTLSCert(orgName string, dnsName string) (string, string, error) {
+	template := &x509.Certificate{
+		SerialNumber: big.NewInt(int64(acctest.RandInt())),
+		Subject: pkix.Name{
+			Organization: []string{orgName},
+		},
+		NotBefore:             time.Now(),
+		NotAfter:              time.Now().Add(24 * time.Hour),
+		KeyUsage:              x509.KeyUsageKeyEncipherment | x509.KeyUsageDigitalSignature,
+		ExtKeyUsage:           []x509.ExtKeyUsage{x509.ExtKeyUsageServerAuth},
+		BasicConstraintsValid: true,
+		DNSNames:              []string{dnsName},
+	}
+
+	privateKey, privateKeyPEM, err := genPrivateKey()
+	if err != nil {
+		return "", "", err
+	}
+
+	cert, err := x509.CreateCertificate(crand.Reader, template, template, &privateKey.PublicKey, privateKey)
+	if err != nil {
+		return "", "", err
+	}
+
+	certPEM, err := pemEncode(cert, "CERTIFICATE")
+	if err != nil {
+		return "", "", err
+	}
+
+	return certPEM, privateKeyPEM, nil
+}
+
+func genPrivateKey() (*rsa.PrivateKey, string, error) {
+	privateKey, err := rsa.GenerateKey(crand.Reader, 1024)
+	if err != nil {
+		return nil, "", err
+	}
+
+	privateKeyPEM, err := pemEncode(x509.MarshalPKCS1PrivateKey(privateKey), "RSA PRIVATE KEY")
+	if err != nil {
+		return nil, "", err
+	}
+
+	return privateKey, privateKeyPEM, nil
+}
+
+func pemEncode(b []byte, block string) (string, error) {
+	var buf bytes.Buffer
+	pb := &pem.Block{Type: block, Bytes: b}
+	if err := pem.Encode(&buf, pb); err != nil {
+		return "", err
+	}
+
+	return buf.String(), nil
+}
+
 func testAccCheckDigitalOceanCertificateConfig_basic(rInt int, privateKeyMaterial, leafCert, certChain string) string {
 	return fmt.Sprintf(`
 resource "digitalocean_certificate" "foobar" {