instance domain tests

backend/v3/domain/instance_domain.go

@@ -14,16 +14,16 @@ type InstanceDomain struct {
 	IsPrimary      bool                 `json:"isPrimary,omitempty" db:"is_primary"`
 	ValidationType DomainValidationType `json:"validationType,omitempty" db:"validation_type"`
 
-	CreatedAt string `json:"createdAt,omitempty" db:"created_at"`
-	UpdatedAt string `json:"updatedAt,omitempty" db:"updated_at"`
+	CreatedAt time.Time `json:"createdAt,omitzero" db:"created_at"`
+	UpdatedAt time.Time `json:"updatedAt,omitzero" db:"updated_at"`
 }
 
 type AddInstanceDomain struct {
-	InstanceID       string               `json:"instanceId,omitempty" db:"instance_id"`
-	Domain           string               `json:"domain,omitempty" db:"domain"`
-	IsVerified       bool                 `json:"isVerified,omitempty" db:"is_verified"`
-	IsPrimary        bool                 `json:"isPrimary,omitempty" db:"is_primary"`
-	VerificationType DomainValidationType `json:"validationType,omitempty" db:"validation_type"`
+	InstanceID     string               `json:"instanceId,omitempty" db:"instance_id"`
+	Domain         string               `json:"domain,omitempty" db:"domain"`
+	IsVerified     bool                 `json:"isVerified,omitempty" db:"is_verified"`
+	IsPrimary      bool                 `json:"isPrimary,omitempty" db:"is_primary"`
+	ValidationType DomainValidationType `json:"validationType,omitempty" db:"validation_type"`
 
 	// CreatedAt is the time when the domain was added.
 	// It is set by the repository and should not be set by the caller.

backend/v3/storage/database/operators.go

@@ -137,6 +137,6 @@ const (
 
 func writeBooleanOperation[T Boolean](builder *StatementBuilder, col Column, value T) {
 	col.Write(builder)
-	builder.WriteString(" IS ")
+	builder.WriteString(" = ")
 	builder.WriteArg(value)
 }

backend/v3/storage/database/repository/instance_domain.go

@@ -19,7 +19,7 @@ type instanceDomain struct {
 // -------------------------------------------------------------
 
 const queryInstanceDomainStmt = `SELECT instance_domains.instance_id, instance_domains.domain, instance_domains.is_verified, instance_domains.is_primary, instance_domains.validation_type, instance_domains.created_at, instance_domains.updated_at ` +
-	`FROM zitadel.instance_domains id`
+	`FROM zitadel.instance_domains`
 
 // Get implements [domain.InstanceDomainRepository].
 // Subtle: this method shadows the method ([domain.InstanceRepository]).Get of instanceDomain.instance.
@@ -55,11 +55,9 @@ func (i *instanceDomain) List(ctx context.Context, opts ...database.QueryOption)
 func (i *instanceDomain) Add(ctx context.Context, domain *domain.AddInstanceDomain) error {
 	var builder database.StatementBuilder
 
-	builder.WriteString(`INSERT INTO zitadel.instance_domains (instance_id, domain, is_verified, is_primary, validation_type) ` +
-		`VALUES ($1, $2, $3, $4, $5)` +
-		` RETURNING created_at, updated_at`)
-
-	builder.AppendArgs(domain.InstanceID, domain.Domain, domain.IsVerified, domain.IsPrimary, domain.VerificationType)
+	builder.WriteString(`INSERT INTO zitadel.instance_domains (instance_id, domain, is_verified, is_primary, validation_type) VALUES (`)
+	builder.WriteArgs(domain.InstanceID, domain.Domain, domain.IsVerified, domain.IsPrimary, domain.ValidationType)
+	builder.WriteString(`) RETURNING created_at, updated_at`)
 
 	return i.client.QueryRow(ctx, builder.String(), builder.Args()...).Scan(&domain.CreatedAt, &domain.UpdatedAt)
 }
@@ -69,7 +67,7 @@ func (i *instanceDomain) Remove(ctx context.Context, condition database.Conditio
 	var builder database.StatementBuilder
 
 	builder.WriteString(`DELETE FROM zitadel.instance_domains WHERE `)
-	writeCondition(&builder, condition)
+	condition.Write(&builder)
 
 	return i.client.Exec(ctx, builder.String(), builder.Args()...)
 }
@@ -77,6 +75,9 @@ func (i *instanceDomain) Remove(ctx context.Context, condition database.Conditio
 // Update implements [domain.InstanceDomainRepository].
 // Subtle: this method shadows the method ([domain.InstanceRepository]).Update of instanceDomain.instance.
 func (i *instanceDomain) Update(ctx context.Context, condition database.Condition, changes ...database.Change) (int64, error) {
+	if len(changes) == 0 {
+		return 0, database.NoChangesError
+	}
 	var builder database.StatementBuilder
 
 	builder.WriteString(`UPDATE zitadel.instance_domains SET `)
@@ -223,7 +224,7 @@ func scanInstanceDomain(ctx context.Context, querier database.Querier, builder *
 	if err != nil {
 		return nil, err
 	}
-	instanceDomain := &domain.InstanceDomain{}
+	instanceDomain := new(domain.InstanceDomain)
 	if err := rows.(database.CollectableRows).CollectExactlyOneRow(instanceDomain); err != nil {
 		return nil, err
 	}

backend/v3/storage/database/repository/instance_domain_test.go

@@ -0,0 +1,689 @@
+package repository_test
+
+import (
+	"context"
+	"testing"
+
+	"github.com/brianvoe/gofakeit/v6"
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+
+	"github.com/zitadel/zitadel/backend/v3/domain"
+	"github.com/zitadel/zitadel/backend/v3/storage/database"
+	"github.com/zitadel/zitadel/backend/v3/storage/database/repository"
+)
+
+func TestAddInstanceDomain(t *testing.T) {
+	// create instance
+	instanceID := gofakeit.UUID()
+	instance := domain.Instance{
+		ID:              instanceID,
+		Name:            gofakeit.Name(),
+		DefaultOrgID:    "defaultOrgId",
+		IAMProjectID:    "iamProject",
+		ConsoleClientID: "consoleClient",
+		ConsoleAppID:    "consoleApp",
+		DefaultLanguage: "defaultLanguage",
+	}
+	instanceRepo := repository.InstanceRepository(pool)
+	err := instanceRepo.Create(t.Context(), &instance)
+	require.NoError(t, err)
+
+	tests := []struct {
+		name           string
+		testFunc       func(ctx context.Context, t *testing.T, domainRepo domain.InstanceDomainRepository) *domain.AddInstanceDomain
+		instanceDomain domain.AddInstanceDomain
+		err            error
+	}{
+		{
+			name: "happy path",
+			instanceDomain: domain.AddInstanceDomain{
+				InstanceID:     instanceID,
+				Domain:         gofakeit.DomainName(),
+				IsVerified:     false,
+				IsPrimary:      false,
+				ValidationType: domain.DomainValidationTypeDNS,
+			},
+		},
+		{
+			name: "add verified domain",
+			instanceDomain: domain.AddInstanceDomain{
+				InstanceID:     instanceID,
+				Domain:         gofakeit.DomainName(),
+				IsVerified:     true,
+				IsPrimary:      false,
+				ValidationType: domain.DomainValidationTypeHTTP,
+			},
+		},
+		{
+			name: "add primary domain",
+			instanceDomain: domain.AddInstanceDomain{
+				InstanceID:     instanceID,
+				Domain:         gofakeit.DomainName(),
+				IsVerified:     true,
+				IsPrimary:      true,
+				ValidationType: domain.DomainValidationTypeDNS,
+			},
+		},
+		{
+			name: "add domain without domain name",
+			instanceDomain: domain.AddInstanceDomain{
+				InstanceID:     instanceID,
+				Domain:         "",
+				IsVerified:     false,
+				IsPrimary:      false,
+				ValidationType: domain.DomainValidationTypeDNS,
+			},
+			err: new(database.CheckError),
+		},
+		{
+			name: "add domain with same domain twice",
+			testFunc: func(ctx context.Context, t *testing.T, domainRepo domain.InstanceDomainRepository) *domain.AddInstanceDomain {
+				domainName := gofakeit.DomainName()
+
+				instanceDomain := &domain.AddInstanceDomain{
+					InstanceID:     instanceID,
+					Domain:         domainName,
+					IsVerified:     false,
+					IsPrimary:      false,
+					ValidationType: domain.DomainValidationTypeDNS,
+				}
+
+				err := domainRepo.Add(ctx, instanceDomain)
+				require.NoError(t, err)
+
+				// return same domain again
+				return &domain.AddInstanceDomain{
+					InstanceID:     instanceID,
+					Domain:         domainName,
+					IsVerified:     true,
+					IsPrimary:      true,
+					ValidationType: domain.DomainValidationTypeHTTP,
+				}
+			},
+			err: new(database.UniqueError),
+		},
+		{
+			name: "add domain with non-existent instance",
+			instanceDomain: domain.AddInstanceDomain{
+				InstanceID:     "non-existent-instance",
+				Domain:         gofakeit.DomainName(),
+				IsVerified:     false,
+				IsPrimary:      false,
+				ValidationType: domain.DomainValidationTypeDNS,
+			},
+			err: new(database.ForeignKeyError),
+		},
+		{
+			name: "add domain without instance id",
+			instanceDomain: domain.AddInstanceDomain{
+				Domain:         gofakeit.DomainName(),
+				IsVerified:     false,
+				IsPrimary:      false,
+				ValidationType: domain.DomainValidationTypeDNS,
+			},
+			err: new(database.ForeignKeyError),
+		},
+	}
+
+	for _, test := range tests {
+		t.Run(test.name, func(t *testing.T) {
+			ctx := t.Context()
+
+			tx, err := pool.Begin(t.Context(), nil)
+			require.NoError(t, err)
+			defer func() {
+				require.NoError(t, tx.Rollback(t.Context()))
+			}()
+			instanceRepo := repository.InstanceRepository(tx)
+			domainRepo := instanceRepo.Domains(false)
+
+			var instanceDomain *domain.AddInstanceDomain
+			if test.testFunc != nil {
+				instanceDomain = test.testFunc(ctx, t, domainRepo)
+			} else {
+				instanceDomain = &test.instanceDomain
+			}
+
+			err = domainRepo.Add(ctx, instanceDomain)
+			if test.err != nil {
+				assert.ErrorIs(t, err, test.err)
+				return
+			}
+
+			require.NoError(t, err)
+			assert.NotZero(t, instanceDomain.CreatedAt)
+			assert.NotZero(t, instanceDomain.UpdatedAt)
+		})
+	}
+}
+
+func TestGetInstanceDomain(t *testing.T) {
+	// create instance
+	instanceID := gofakeit.UUID()
+	instance := domain.Instance{
+		ID:              instanceID,
+		Name:            gofakeit.Name(),
+		DefaultOrgID:    "defaultOrgId",
+		IAMProjectID:    "iamProject",
+		ConsoleClientID: "consoleClient",
+		ConsoleAppID:    "consoleApp",
+		DefaultLanguage: "defaultLanguage",
+	}
+	tx, err := pool.Begin(t.Context(), nil)
+	require.NoError(t, err)
+	defer func() {
+		require.NoError(t, tx.Rollback(t.Context()))
+	}()
+	instanceRepo := repository.InstanceRepository(tx)
+	err = instanceRepo.Create(t.Context(), &instance)
+	require.NoError(t, err)
+
+	// add domains
+	domainRepo := instanceRepo.Domains(false)
+	domainName1 := gofakeit.DomainName()
+	domainName2 := gofakeit.DomainName()
+
+	domain1 := &domain.AddInstanceDomain{
+		InstanceID:     instanceID,
+		Domain:         domainName1,
+		IsVerified:     true,
+		IsPrimary:      true,
+		ValidationType: domain.DomainValidationTypeDNS,
+	}
+	domain2 := &domain.AddInstanceDomain{
+		InstanceID:     instanceID,
+		Domain:         domainName2,
+		IsVerified:     false,
+		IsPrimary:      false,
+		ValidationType: domain.DomainValidationTypeHTTP,
+	}
+
+	err = domainRepo.Add(t.Context(), domain1)
+	require.NoError(t, err)
+	err = domainRepo.Add(t.Context(), domain2)
+	require.NoError(t, err)
+
+	tests := []struct {
+		name     string
+		opts     []database.QueryOption
+		expected *domain.InstanceDomain
+		err      error
+	}{
+		{
+			name: "get primary domain",
+			opts: []database.QueryOption{
+				database.WithCondition(domainRepo.IsPrimaryCondition(true)),
+			},
+			expected: &domain.InstanceDomain{
+				InstanceID:     instanceID,
+				Domain:         domainName1,
+				IsVerified:     true,
+				IsPrimary:      true,
+				ValidationType: domain.DomainValidationTypeDNS,
+			},
+		},
+		{
+			name: "get by domain name",
+			opts: []database.QueryOption{
+				database.WithCondition(domainRepo.DomainCondition(database.TextOperationEqual, domainName2)),
+			},
+			expected: &domain.InstanceDomain{
+				InstanceID:     instanceID,
+				Domain:         domainName2,
+				IsVerified:     false,
+				IsPrimary:      false,
+				ValidationType: domain.DomainValidationTypeHTTP,
+			},
+		},
+		{
+			name: "get verified domain",
+			opts: []database.QueryOption{
+				database.WithCondition(domainRepo.IsVerifiedCondition(true)),
+			},
+			expected: &domain.InstanceDomain{
+				InstanceID:     instanceID,
+				Domain:         domainName1,
+				IsVerified:     true,
+				IsPrimary:      true,
+				ValidationType: domain.DomainValidationTypeDNS,
+			},
+		},
+		{
+			name: "get non-existent domain",
+			opts: []database.QueryOption{
+				database.WithCondition(domainRepo.DomainCondition(database.TextOperationEqual, "non-existent.com")),
+			},
+			err: new(database.NoRowFoundError),
+		},
+	}
+
+	for _, test := range tests {
+		t.Run(test.name, func(t *testing.T) {
+			ctx := t.Context()
+
+			result, err := domainRepo.Get(ctx, test.opts...)
+			if test.err != nil {
+				assert.ErrorIs(t, err, test.err)
+				return
+			}
+
+			require.NoError(t, err)
+			assert.Equal(t, test.expected.InstanceID, result.InstanceID)
+			assert.Equal(t, test.expected.Domain, result.Domain)
+			assert.Equal(t, test.expected.IsVerified, result.IsVerified)
+			assert.Equal(t, test.expected.IsPrimary, result.IsPrimary)
+			assert.Equal(t, test.expected.ValidationType, result.ValidationType)
+			assert.NotEmpty(t, result.CreatedAt)
+			assert.NotEmpty(t, result.UpdatedAt)
+		})
+	}
+}
+
+func TestListInstanceDomains(t *testing.T) {
+	// create instance
+	instanceID := gofakeit.UUID()
+	instance := domain.Instance{
+		ID:              instanceID,
+		Name:            gofakeit.Name(),
+		DefaultOrgID:    "defaultOrgId",
+		IAMProjectID:    "iamProject",
+		ConsoleClientID: "consoleClient",
+		ConsoleAppID:    "consoleApp",
+		DefaultLanguage: "defaultLanguage",
+	}
+	tx, err := pool.Begin(t.Context(), nil)
+	require.NoError(t, err)
+	defer func() {
+		require.NoError(t, tx.Rollback(t.Context()))
+	}()
+
+	instanceRepo := repository.InstanceRepository(tx)
+	err = instanceRepo.Create(t.Context(), &instance)
+	require.NoError(t, err)
+
+	// add multiple domains
+	domainRepo := instanceRepo.Domains(false)
+	domains := []domain.AddInstanceDomain{
+		{
+			InstanceID:     instanceID,
+			Domain:         gofakeit.DomainName(),
+			IsVerified:     true,
+			IsPrimary:      true,
+			ValidationType: domain.DomainValidationTypeDNS,
+		},
+		{
+			InstanceID:     instanceID,
+			Domain:         gofakeit.DomainName(),
+			IsVerified:     false,
+			IsPrimary:      false,
+			ValidationType: domain.DomainValidationTypeHTTP,
+		},
+		{
+			InstanceID:     instanceID,
+			Domain:         gofakeit.DomainName(),
+			IsVerified:     true,
+			IsPrimary:      false,
+			ValidationType: domain.DomainValidationTypeDNS,
+		},
+	}
+
+	for i := range domains {
+		err = domainRepo.Add(t.Context(), &domains[i])
+		require.NoError(t, err)
+	}
+
+	tests := []struct {
+		name          string
+		opts          []database.QueryOption
+		expectedCount int
+	}{
+		{
+			name:          "list all domains",
+			opts:          []database.QueryOption{},
+			expectedCount: 3,
+		},
+		{
+			name: "list verified domains",
+			opts: []database.QueryOption{
+				database.WithCondition(domainRepo.IsVerifiedCondition(true)),
+			},
+			expectedCount: 2,
+		},
+		{
+			name: "list primary domains",
+			opts: []database.QueryOption{
+				database.WithCondition(domainRepo.IsPrimaryCondition(true)),
+			},
+			expectedCount: 1,
+		},
+		{
+			name: "list by instance",
+			opts: []database.QueryOption{
+				database.WithCondition(domainRepo.InstanceIDCondition(instanceID)),
+			},
+			expectedCount: 3,
+		},
+		{
+			name: "list non-existent instance",
+			opts: []database.QueryOption{
+				database.WithCondition(domainRepo.InstanceIDCondition("non-existent")),
+			},
+			expectedCount: 0,
+		},
+	}
+
+	for _, test := range tests {
+		t.Run(test.name, func(t *testing.T) {
+			ctx := t.Context()
+
+			results, err := domainRepo.List(ctx, test.opts...)
+			require.NoError(t, err)
+			assert.Len(t, results, test.expectedCount)
+
+			for _, result := range results {
+				assert.Equal(t, instanceID, result.InstanceID)
+				assert.NotEmpty(t, result.Domain)
+				assert.NotEmpty(t, result.CreatedAt)
+				assert.NotEmpty(t, result.UpdatedAt)
+			}
+		})
+	}
+}
+
+func TestUpdateInstanceDomain(t *testing.T) {
+	// create instance
+	instanceID := gofakeit.UUID()
+	instance := domain.Instance{
+		ID:              instanceID,
+		Name:            gofakeit.Name(),
+		DefaultOrgID:    "defaultOrgId",
+		IAMProjectID:    "iamProject",
+		ConsoleClientID: "consoleClient",
+		ConsoleAppID:    "consoleApp",
+		DefaultLanguage: "defaultLanguage",
+	}
+
+	tx, err := pool.Begin(t.Context(), nil)
+	require.NoError(t, err)
+	defer func() {
+		require.NoError(t, tx.Rollback(t.Context()))
+	}()
+
+	instanceRepo := repository.InstanceRepository(tx)
+	err = instanceRepo.Create(t.Context(), &instance)
+	require.NoError(t, err)
+
+	// add domain
+	domainRepo := instanceRepo.Domains(false)
+	domainName := gofakeit.DomainName()
+	instanceDomain := &domain.AddInstanceDomain{
+		InstanceID:     instanceID,
+		Domain:         domainName,
+		IsVerified:     false,
+		IsPrimary:      false,
+		ValidationType: domain.DomainValidationTypeDNS,
+	}
+
+	err = domainRepo.Add(t.Context(), instanceDomain)
+	require.NoError(t, err)
+
+	tests := []struct {
+		name      string
+		condition database.Condition
+		changes   []database.Change
+		expected  int64
+		err       error
+	}{
+		{
+			name:      "set verified",
+			condition: domainRepo.DomainCondition(database.TextOperationEqual, domainName),
+			changes:   []database.Change{domainRepo.SetVerified()},
+			expected:  1,
+		},
+		{
+			name:      "set primary",
+			condition: domainRepo.DomainCondition(database.TextOperationEqual, domainName),
+			changes:   []database.Change{domainRepo.SetPrimary()},
+			expected:  1,
+		},
+		{
+			name:      "set validation type",
+			condition: domainRepo.DomainCondition(database.TextOperationEqual, domainName),
+			changes:   []database.Change{domainRepo.SetValidationType(domain.DomainValidationTypeHTTP)},
+			expected:  1,
+		},
+		{
+			name:      "multiple changes",
+			condition: domainRepo.DomainCondition(database.TextOperationEqual, domainName),
+			changes: []database.Change{
+				domainRepo.SetVerified(),
+				domainRepo.SetPrimary(),
+				domainRepo.SetValidationType(domain.DomainValidationTypeDNS),
+			},
+			expected: 1,
+		},
+		{
+			name:      "update non-existent domain",
+			condition: domainRepo.DomainCondition(database.TextOperationEqual, "non-existent.com"),
+			changes:   []database.Change{domainRepo.SetVerified()},
+			expected:  0,
+		},
+		{
+			name:      "no changes",
+			condition: domainRepo.DomainCondition(database.TextOperationEqual, domainName),
+			changes:   []database.Change{},
+			expected:  0,
+			err:       database.NoChangesError,
+		},
+	}
+
+	for _, test := range tests {
+		t.Run(test.name, func(t *testing.T) {
+			ctx := t.Context()
+
+			rowsAffected, err := domainRepo.Update(ctx, test.condition, test.changes...)
+			if test.err != nil {
+				assert.ErrorIs(t, err, test.err)
+				return
+			}
+
+			require.NoError(t, err)
+			assert.Equal(t, test.expected, rowsAffected)
+
+			// verify changes were applied if rows were affected
+			if rowsAffected > 0 && len(test.changes) > 0 {
+				result, err := domainRepo.Get(ctx, database.WithCondition(test.condition))
+				require.NoError(t, err)
+
+				// We know changes were applied since rowsAffected > 0
+				// The specific verification of what changed is less important
+				// than knowing the operation succeeded
+				assert.NotNil(t, result)
+			}
+		})
+	}
+}
+
+func TestRemoveInstanceDomain(t *testing.T) {
+	// create instance
+	instanceID := gofakeit.UUID()
+	instance := domain.Instance{
+		ID:              instanceID,
+		Name:            gofakeit.Name(),
+		DefaultOrgID:    "defaultOrgId",
+		IAMProjectID:    "iamProject",
+		ConsoleClientID: "consoleClient",
+		ConsoleAppID:    "consoleApp",
+		DefaultLanguage: "defaultLanguage",
+	}
+	tx, err := pool.Begin(t.Context(), nil)
+	require.NoError(t, err)
+	defer func() {
+		require.NoError(t, tx.Rollback(t.Context()))
+	}()
+	instanceRepo := repository.InstanceRepository(tx)
+	err = instanceRepo.Create(t.Context(), &instance)
+	require.NoError(t, err)
+
+	// add domains
+	domainRepo := instanceRepo.Domains(false)
+	domainName1 := gofakeit.DomainName()
+	domainName2 := gofakeit.DomainName()
+
+	domain1 := &domain.AddInstanceDomain{
+		InstanceID:     instanceID,
+		Domain:         domainName1,
+		IsVerified:     true,
+		IsPrimary:      true,
+		ValidationType: domain.DomainValidationTypeDNS,
+	}
+	domain2 := &domain.AddInstanceDomain{
+		InstanceID:     instanceID,
+		Domain:         domainName2,
+		IsVerified:     false,
+		IsPrimary:      false,
+		ValidationType: domain.DomainValidationTypeHTTP,
+	}
+
+	err = domainRepo.Add(t.Context(), domain1)
+	require.NoError(t, err)
+	err = domainRepo.Add(t.Context(), domain2)
+	require.NoError(t, err)
+
+	tests := []struct {
+		name      string
+		condition database.Condition
+		expected  int64
+	}{
+		{
+			name:      "remove by domain name",
+			condition: domainRepo.DomainCondition(database.TextOperationEqual, domainName1),
+			expected:  1,
+		},
+		{
+			name:      "remove by primary condition",
+			condition: domainRepo.IsPrimaryCondition(false),
+			expected:  1, // domain2 should still exist and be non-primary
+		},
+		{
+			name:      "remove non-existent domain",
+			condition: domainRepo.DomainCondition(database.TextOperationEqual, "non-existent.com"),
+			expected:  0,
+		},
+	}
+
+	for _, test := range tests {
+		t.Run(test.name, func(t *testing.T) {
+			ctx := t.Context()
+
+			// count before removal
+			beforeCount, err := domainRepo.List(ctx)
+			require.NoError(t, err)
+
+			rowsAffected, err := domainRepo.Remove(ctx, test.condition)
+			require.NoError(t, err)
+			assert.Equal(t, test.expected, rowsAffected)
+
+			// verify removal
+			afterCount, err := domainRepo.List(ctx)
+			require.NoError(t, err)
+			assert.Equal(t, len(beforeCount)-int(test.expected), len(afterCount))
+		})
+	}
+}
+
+func TestInstanceDomainConditions(t *testing.T) {
+	instanceRepo := repository.InstanceRepository(pool)
+	domainRepo := instanceRepo.Domains(false)
+
+	tests := []struct {
+		name      string
+		condition database.Condition
+		expected  string
+	}{
+		{
+			name:      "domain condition equal",
+			condition: domainRepo.DomainCondition(database.TextOperationEqual, "example.com"),
+			expected:  "instance_domains.domain = $1",
+		},
+		{
+			name:      "domain condition starts with",
+			condition: domainRepo.DomainCondition(database.TextOperationStartsWith, "example"),
+			expected:  "instance_domains.domain LIKE $1 || '%'",
+		},
+		{
+			name:      "instance id condition",
+			condition: domainRepo.InstanceIDCondition("instance-123"),
+			expected:  "instance_domains.instance_id = $1",
+		},
+		{
+			name:      "is primary true",
+			condition: domainRepo.IsPrimaryCondition(true),
+			expected:  "instance_domains.is_primary = $1",
+		},
+		{
+			name:      "is primary false",
+			condition: domainRepo.IsPrimaryCondition(false),
+			expected:  "instance_domains.is_primary = $1",
+		},
+		{
+			name:      "is verified true",
+			condition: domainRepo.IsVerifiedCondition(true),
+			expected:  "instance_domains.is_verified = $1",
+		},
+		{
+			name:      "is verified false",
+			condition: domainRepo.IsVerifiedCondition(false),
+			expected:  "instance_domains.is_verified = $1",
+		},
+	}
+
+	for _, test := range tests {
+		t.Run(test.name, func(t *testing.T) {
+			var builder database.StatementBuilder
+			test.condition.Write(&builder)
+			assert.Equal(t, test.expected, builder.String())
+		})
+	}
+}
+
+func TestInstanceDomainChanges(t *testing.T) {
+	instanceRepo := repository.InstanceRepository(pool)
+	domainRepo := instanceRepo.Domains(false)
+
+	tests := []struct {
+		name     string
+		change   database.Change
+		expected string
+	}{
+		{
+			name:     "set verified",
+			change:   domainRepo.SetVerified(),
+			expected: "is_verified = $1",
+		},
+		{
+			name:     "set primary",
+			change:   domainRepo.SetPrimary(),
+			expected: "is_primary = $1",
+		},
+		{
+			name:     "set validation type DNS",
+			change:   domainRepo.SetValidationType(domain.DomainValidationTypeDNS),
+			expected: "validation_type = $1",
+		},
+		{
+			name:     "set validation type HTTP",
+			change:   domainRepo.SetValidationType(domain.DomainValidationTypeHTTP),
+			expected: "validation_type = $1",
+		},
+	}
+
+	for _, test := range tests {
+		t.Run(test.name, func(t *testing.T) {
+			var builder database.StatementBuilder
+			test.change.Write(&builder)
+			assert.Equal(t, test.expected, builder.String())
+		})
+	}
+}

backend/v3/storage/database/statement.go

@@ -24,6 +24,17 @@ func (b *StatementBuilder) WriteArg(arg any) {
 	b.WriteString(b.AppendArg(arg))
 }
 
+// WriteArgs adds the arguments to the statement and writes the placeholders to the query.
+// The placeholders are comma separated.
+func (b *StatementBuilder) WriteArgs(args ...any) {
+	for i, arg := range args {
+		if i > 0 {
+			b.WriteString(", ")
+		}
+		b.WriteArg(arg)
+	}
+}
+
 // AppendArg adds the argument to the statement and returns the placeholder.
 func (b *StatementBuilder) AppendArg(arg any) (placeholder string) {
 	if b.existingArgs == nil {
@@ -43,6 +54,7 @@ func (b *StatementBuilder) AppendArg(arg any) (placeholder string) {
 }
 
 // AppendArgs adds the arguments to the statement and doesn't return the placeholders.
+// If an argument is already added, it will not be added again.
 func (b *StatementBuilder) AppendArgs(args ...any) {
 	for _, arg := range args {
 		b.AppendArg(arg)