fix postgres constraints, add postgres testing

This commit fixes the constraint syntax so it is both valid for
sqlite and postgres.

To validate this, I've added a new postgres testing library and a
helper that will spin up local postgres, setup a db and use it in
the constraints tests. This should also help testing db stuff in
the future.

postgres has been added to the nix dev shell and is now required
for running the unit tests.

Signed-off-by: Kristoffer Dalby <kristoffer@tailscale.com>

flake.nix

@@ -32,7 +32,7 @@
 
           # When updating go.mod or go.sum, a new sha will need to be calculated,
           # update this if you have a mismatch after doing a change to thos files.
-          vendorHash = "sha256-Qoqu2k4vvnbRFLmT/v8lI+HCEWqJsHFs8uZRfNmwQpo=";
+          vendorHash = "sha256-4VNiHUblvtcl9UetwiL6ZeVYb0h2e9zhYVsirhAkvOg=";
 
           subPackages = ["cmd/headscale"];
 
@@ -102,6 +102,7 @@
           ko
           yq-go
           ripgrep
+          postgresql
 
           # 'dot' is needed for pprof graphs
           # go tool pprof -http=: <source>

go.mod

@@ -49,6 +49,7 @@ require (
 	gorm.io/gorm v1.25.11
 	tailscale.com v1.75.0-pre.0.20240926101731-7d1160ddaab7
 	zgo.at/zcache/v2 v2.1.0
+	zombiezen.com/go/postgrestest v1.0.1
 )
 
 require (
@@ -134,6 +135,7 @@ require (
 	github.com/kortschak/wol v0.0.0-20200729010619-da482cc4850a // indirect
 	github.com/kr/pretty v0.3.1 // indirect
 	github.com/kr/text v0.2.0 // indirect
+	github.com/lib/pq v1.10.9 // indirect
 	github.com/lithammer/fuzzysearch v1.1.8 // indirect
 	github.com/mattn/go-colorable v0.1.13 // indirect
 	github.com/mattn/go-isatty v0.0.20 // indirect

go.sum

@@ -311,6 +311,7 @@ github.com/kr/text v0.2.0/go.mod h1:eLer722TekiGuMkidMxC/pM04lWEeraHUUmBw8l2grE=
 github.com/kylelemons/godebug v1.1.0 h1:RPNrshWIDI6G2gRW9EHilWtl7Z6Sb1BR0xunSBf0SNc=
 github.com/kylelemons/godebug v1.1.0/go.mod h1:9/0rRGxNHcop5bhtWyNeEfOS8JIWk580+fNqagV/RAw=
 github.com/ledongthuc/pdf v0.0.0-20220302134840-0c2507a12d80/go.mod h1:imJHygn/1yfhB7XSJJKlFZKl/J+dCPAknuiaGOshXAs=
+github.com/lib/pq v1.8.0/go.mod h1:AlVN5x4E4T544tWzH6hKfbfQvm3HdbOxrmggDNAPY9o=
 github.com/lib/pq v1.10.9 h1:YXG7RB+JIjhP29X+OtkiDnYaXQwpS4JEWq7dtCCRUEw=
 github.com/lib/pq v1.10.9/go.mod h1:AlVN5x4E4T544tWzH6hKfbfQvm3HdbOxrmggDNAPY9o=
 github.com/lithammer/fuzzysearch v1.1.8 h1:/HIuJnjHuXS8bKaiTMeeDlW2/AyIWk2brx1V8LFgLN4=
@@ -731,3 +732,5 @@ tailscale.com v1.75.0-pre.0.20240926101731-7d1160ddaab7 h1:nfRWV6ECxwNvvXKtbqSVs
 tailscale.com v1.75.0-pre.0.20240926101731-7d1160ddaab7/go.mod h1:xKxYf3B3PuezFlRaMT+VhuVu8XTFUTLy+VCzLPMJVmg=
 zgo.at/zcache/v2 v2.1.0 h1:USo+ubK+R4vtjw4viGzTe/zjXyPw6R7SK/RL3epBBxs=
 zgo.at/zcache/v2 v2.1.0/go.mod h1:gyCeoLVo01QjDZynjime8xUGHHMbsLiPyUTBpDGd4Gk=
+zombiezen.com/go/postgrestest v1.0.1 h1:aXoADQAJmZDU3+xilYVut0pHhgc0sF8ZspPW9gFNwP4=
+zombiezen.com/go/postgrestest v1.0.1/go.mod h1:marlZezr+k2oSJrvXHnZUs1olHqpE9czlz8ZYkVxliQ=

hscontrol/db/db.go

@@ -505,11 +505,11 @@ func NewHeadscaleDatabase(
 					// - A provider_identifier is unique
 					// - A user name is unique if there is no provider_identifier is not set
 					for _, idx := range []string{
-						"DROP INDEX IF EXISTS `idx_provider_identifier`",
+						"DROP INDEX IF EXISTS idx_provider_identifier",
-						"DROP INDEX IF EXISTS `idx_name_provider_identifier`",
+						"DROP INDEX IF EXISTS idx_name_provider_identifier",
-						"CREATE UNIQUE INDEX IF NOT EXISTS `idx_provider_identifier` ON `users` (`provider_identifier`) WHERE provider_identifier IS NOT NULL;",
+						"CREATE UNIQUE INDEX IF NOT EXISTS idx_provider_identifier ON users (provider_identifier) WHERE provider_identifier IS NOT NULL;",
-						"CREATE UNIQUE INDEX IF NOT EXISTS `idx_name_provider_identifier` ON `users` (`name`,`provider_identifier`);",
+						"CREATE UNIQUE INDEX IF NOT EXISTS idx_name_provider_identifier ON users (name,provider_identifier);",
-						"CREATE UNIQUE INDEX IF NOT EXISTS `idx_name_no_provider_identifier` ON `users` (`name`) WHERE provider_identifier IS NULL;",
+						"CREATE UNIQUE INDEX IF NOT EXISTS idx_name_no_provider_identifier ON users (name) WHERE provider_identifier IS NULL;",
 					} {
 						err = tx.Exec(idx).Error
 						if err != nil {

hscontrol/db/db_test.go

@@ -9,6 +9,7 @@ import (
 	"path/filepath"
 	"slices"
 	"sort"
+	"strings"
 	"testing"
 	"time"
 
@@ -259,6 +260,16 @@ func emptyCache() *zcache.Cache[string, types.Node] {
 	return zcache.New[string, types.Node](time.Minute, time.Hour)
 }
 
+// requireConstraintFailed checks if the error is a constraint failure with
+// either SQLite and PostgreSQL error messages.
+func requireConstraintFailed(t *testing.T, err error) {
+	t.Helper()
+	require.Error(t, err)
+	if !strings.Contains(err.Error(), "UNIQUE constraint failed:") && !strings.Contains(err.Error(), "violates unique constraint") {
+		require.Failf(t, "expected error to contain a constraint failure, got: %s", err.Error())
+	}
+}
+
 func TestConstraints(t *testing.T) {
 	tests := []struct {
 		name string
@@ -270,9 +281,7 @@ func TestConstraints(t *testing.T) {
 				_, err := CreateUser(db, "user1")
 				require.NoError(t, err)
 				_, err = CreateUser(db, "user1")
-				require.Error(t, err)
+				requireConstraintFailed(t, err)
-				assert.Contains(t, err.Error(), "UNIQUE constraint failed:")
-				// require.Contains(t, err.Error(), "user already exists")
 			},
 		},
 		{
@@ -294,8 +303,7 @@ func TestConstraints(t *testing.T) {
 				user.ProviderIdentifier = sql.NullString{String: "http://test.com/user1", Valid: true}
 
 				err = db.Save(&user).Error
-				require.Error(t, err)
+				requireConstraintFailed(t, err)
-				require.Contains(t, err.Error(), "UNIQUE constraint failed:")
 			},
 		},
 		{
@@ -317,8 +325,7 @@ func TestConstraints(t *testing.T) {
 				user.ProviderIdentifier = sql.NullString{String: "http://test.com/user1", Valid: true}
 
 				err = db.Save(&user).Error
-				require.Error(t, err)
+				requireConstraintFailed(t, err)
-				require.Contains(t, err.Error(), "UNIQUE constraint failed:")
 			},
 		},
 		{
@@ -354,8 +361,12 @@ func TestConstraints(t *testing.T) {
 	}
 
 	for _, tt := range tests {
-		t.Run(tt.name, func(t *testing.T) {
+		t.Run(tt.name+"-postgres", func(t *testing.T) {
-			db, err := newTestDB()
+			db := newPostgresTestDB(t)
+			tt.run(t, db.DB.Debug())
+		})
+		t.Run(tt.name+"-sqlite", func(t *testing.T) {
+			db, err := newSQLiteTestDB()
 			if err != nil {
 				t.Fatalf("creating database: %s", err)
 			}

hscontrol/db/node_test.go

@@ -558,7 +558,7 @@ func TestAutoApproveRoutes(t *testing.T) {
 
 	for _, tt := range tests {
 		t.Run(tt.name, func(t *testing.T) {
-			adb, err := newTestDB()
+			adb, err := newSQLiteTestDB()
 			require.NoError(t, err)
 			pol, err := policy.LoadACLPolicyFromBytes([]byte(tt.acl))
 
@@ -692,7 +692,7 @@ func generateRandomNumber(t *testing.T, max int64) int64 {
 }
 
 func TestListEphemeralNodes(t *testing.T) {
-	db, err := newTestDB()
+	db, err := newSQLiteTestDB()
 	if err != nil {
 		t.Fatalf("creating db: %s", err)
 	}
@@ -748,7 +748,7 @@ func TestListEphemeralNodes(t *testing.T) {
 }
 
 func TestRenameNode(t *testing.T) {
-	db, err := newTestDB()
+	db, err := newSQLiteTestDB()
 	if err != nil {
 		t.Fatalf("creating db: %s", err)
 	}

hscontrol/db/suite_test.go

@@ -1,12 +1,17 @@
 package db
 
 import (
+	"context"
 	"log"
+	"net/url"
 	"os"
+	"strconv"
+	"strings"
 	"testing"
 
 	"github.com/juanfont/headscale/hscontrol/types"
 	"gopkg.in/check.v1"
+	"zombiezen.com/go/postgrestest"
 )
 
 func Test(t *testing.T) {
@@ -36,13 +41,15 @@ func (s *Suite) ResetDB(c *check.C) {
 	// }
 
 	var err error
-	db, err = newTestDB()
+	db, err = newSQLiteTestDB()
 	if err != nil {
 		c.Fatal(err)
 	}
 }
 
-func newTestDB() (*HSDatabase, error) {
+// TODO(kradalby): make this a t.Helper when we dont depend
+// on check test framework.
+func newSQLiteTestDB() (*HSDatabase, error) {
 	var err error
 	tmpDir, err = os.MkdirTemp("", "headscale-db-test-*")
 	if err != nil {
@@ -53,7 +60,7 @@ func newTestDB() (*HSDatabase, error) {
 
 	db, err = NewHeadscaleDatabase(
 		types.DatabaseConfig{
-			Type: "sqlite3",
+			Type: types.DatabaseSqlite,
 			Sqlite: types.SqliteConfig{
 				Path: tmpDir + "/headscale_test.db",
 			},
@@ -67,3 +74,53 @@ func newTestDB() (*HSDatabase, error) {
 
 	return db, nil
 }
+
+func newPostgresTestDB(t *testing.T) *HSDatabase {
+	t.Helper()
+
+	var err error
+	tmpDir, err = os.MkdirTemp("", "headscale-db-test-*")
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	log.Printf("database path: %s", tmpDir+"/headscale_test.db")
+
+	ctx := context.Background()
+	srv, err := postgrestest.Start(ctx)
+	if err != nil {
+		t.Fatal(err)
+	}
+	t.Cleanup(srv.Cleanup)
+
+	u, err := srv.CreateDatabase(ctx)
+	if err != nil {
+		t.Fatal(err)
+	}
+	t.Logf("created local postgres: %s", u)
+	pu, _ := url.Parse(u)
+
+	pass, _ := pu.User.Password()
+	port, _ := strconv.Atoi(pu.Port())
+
+	db, err = NewHeadscaleDatabase(
+		types.DatabaseConfig{
+			Type: types.DatabasePostgres,
+			Postgres: types.PostgresConfig{
+				Host: pu.Hostname(),
+				User: pu.User.Username(),
+				Name: strings.TrimLeft(pu.Path, "/"),
+				Pass: pass,
+				Port: port,
+				Ssl:  "disable",
+			},
+		},
+		"",
+		emptyCache(),
+	)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	return db
+}