Finish

app/main.go

@@ -20,15 +20,31 @@ var (
 )
 
 type CertFilter struct {
-	Alive                *bool        `filterfield:"field=alive,operator=EQ"`
-	SerialNumber         *string      `filterfield:"field=serial_number,operator=NE"`
-	SerialNumberContains *string      `filterfield:"field=serial_number,operator=LIKE"`
-	IssuerContains       *string      `filterfield:"field=issuer,operator=ILIKE"`
-	Id                   *uuid.UUID   `filterfield:"field=id,operator=EQ"`
-	Ids                  *[]uuid.UUID `filterfield:"field=id,operator=IN"`
-	IdsNot               *[]string    `filterfield:"field=id,operator=NOT_IN"`
-	CreatedAt_Lt         *time.Time   `filterfield:"field=created_at,operator=LT"`
-	Timestamps           *[]time.Time `filterfield:"field=created_at,operator=IN"`
+	Alive                *bool        `filterfield:"field=alive;operator=EQ"`
+	SerialNumber         *string      `filterfield:"field=serial_number;operator=NE"`
+	SerialNumberContains *string      `filterfield:"field=serial_number;operator=LIKE"`
+	IssuerContains       *string      `filterfield:"field=issuer;operator=ILIKE"`
+	Id                   *uuid.UUID   `filterfield:"field=id;operator=EQ"`
+	Ids                  *[]uuid.UUID `filterfield:"field=id;operator=IN"`
+	IdsNot               *[]string    `filterfield:"field=id;operator=NOT_IN"`
+	CreatedAt_Lt         *time.Time   `filterfield:"field=created_at;operator=LT"`
+	Timestamps           *[]time.Time `filterfield:"field=created_at;operator=IN"`
+	CompanyIsActive      *bool
+}
+
+func (f CertFilter) ApplyQuery(query *gorm.DB) *gorm.DB {
+	if f.CompanyIsActive != nil {
+		query = query.Joins(
+			fmt.Sprintf(
+				"JOIN companies ON certificates.company_id = companies.id WHERE companies.is_active = %t",
+				*f.CompanyIsActive,
+			))
+	}
+	return query
+}
+
+type CompanyFilter struct {
+	IsActive *bool `filterfield:"field=is_active;operator=EQ"`
 }
 
 func doMagic(db *gorm.DB) {
@@ -89,6 +105,24 @@ func doList(db *gorm.DB) {
 	}
 }
 
+func doListWithJoins(db *gorm.DB) {
+	repo := repository.RepoBase[models.Cert]{}
+	repo.Init(db, nil)
+
+	filter := CertFilter{
+		CompanyIsActive: &FALSE,
+	}
+
+	certs, err := repo.List(filter, nil)
+	if err != nil {
+		panic(err)
+	}
+
+	for n, cert := range *certs {
+		fmt.Printf(">> [%d] %+v  %s (alive %t)\n", n, cert.Id, cert.CreatedAt, cert.Alive)
+	}
+}
+
 func doCount(db *gorm.DB) {
 	repo := repository.RepoBase[models.Cert]{}
 	repo.Init(db, nil)
@@ -121,6 +155,40 @@ func doGet(db *gorm.DB) {
 	fmt.Printf(">> %+v  %s (alive %t)\n", cert.Id, cert.CreatedAt, cert.Alive)
 }
 
+func doSave(db *gorm.DB) {
+	repo := repository.RepoBase[models.Company]{}
+	repo.Init(db, nil)
+
+	company := models.Company{
+		Name:    "Test company",
+		Address: "Some address",
+		City:    "Some city",
+		Email:   "email@example.org",
+		Oib:     "123456",
+	}
+
+	_, err := repo.Save(&company)
+	if err != nil {
+		panic(err)
+	}
+	fmt.Printf("New company id: %s\n", company.Id.String())
+}
+
+func doDelete(db *gorm.DB) {
+	repo := repository.RepoBase[models.Company]{}
+	repo.Init(db, nil)
+
+	filter := CompanyFilter{
+		IsActive: &FALSE,
+	}
+
+	deletedCount, err := repo.Delete(filter)
+	if err != nil {
+		panic(err)
+	}
+	fmt.Printf(">> DELETED: %d\n", deletedCount)
+}
+
 func doExists(db *gorm.DB) {
 	repo := repository.RepoBase[models.Cert]{}
 	repo.Init(db, nil)
@@ -147,7 +215,10 @@ func main() {
 
 	// doMagic(db)
 	// doList(db)
-	doCount(db)
+	doListWithJoins(db)
+	// doCount(db)
+	// doSave(db)
+	// doDelete(db)
 	// doGet(db)
 	// doExists(db)
 	// inheritance.DoInheritanceTest()

app/models/company.go

@@ -21,7 +21,7 @@ type Company struct {
 	UpdatedAt     time.Time `faker:"-"`
 }
 
-func (m *Company) TableName() string {
+func (m Company) TableName() string {
 	return "companies"
 }
 

app/repository/method_delete.go

@@ -0,0 +1,31 @@
+package repository
+
+import (
+	"repo-pattern/app/repository/smartfilter"
+
+	"gorm.io/gorm/schema"
+)
+
+type DeleteMethod[T schema.Tabler] struct {
+	repo *RepoBase[T]
+}
+
+func (m *DeleteMethod[T]) Init(repo *RepoBase[T]) {
+	m.repo = repo
+}
+
+func (m DeleteMethod[T]) Delete(filter interface{}) (int64, error) {
+	var (
+		model T
+	)
+
+	query, err := smartfilter.ToQuery(model, filter, m.repo.dbConn)
+	if err != nil {
+		return 0, err
+	}
+	result := query.Delete(&model)
+	if result.Error != nil {
+		return 0, result.Error
+	}
+	return result.RowsAffected, nil
+}

app/repository/method_delete_test.go

@@ -0,0 +1,73 @@
+package repository
+
+import (
+	"fmt"
+	"regexp"
+	"testing"
+
+	"github.com/DATA-DOG/go-sqlmock"
+	"github.com/google/uuid"
+	"github.com/stretchr/testify/assert"
+)
+
+func TestDeleteMethod(t *testing.T) {
+	t.Run("With filter", func(t *testing.T) {
+		sqldb, db, mock := NewMockDB()
+		defer sqldb.Close()
+
+		repo := RepoBase[MyModel]{}
+		repo.Init(db, nil)
+
+		id := uuid.New()
+		filter := MyModelFilter{
+			Id: &id,
+		}
+
+		sql := "DELETE FROM my_models WHERE my_models.id = $1"
+		mock.ExpectBegin()
+		mock.ExpectExec(fmt.Sprintf("^%s$", regexp.QuoteMeta(sql))).
+			WithArgs(id).
+			WillReturnResult(sqlmock.NewResult(1, 111))
+		mock.ExpectCommit()
+
+		deleted, err := repo.Delete(filter)
+		assert.Equal(t, int64(111), deleted)
+		assert.Nil(t, err)
+
+		if err := mock.ExpectationsWereMet(); err != nil {
+			t.Errorf("there were unfulfilled expectations: %s", err)
+		}
+	})
+
+	t.Run("With multiple filters", func(t *testing.T) {
+		sqldb, db, mock := NewMockDB()
+		defer sqldb.Close()
+
+		repo := RepoBase[MyModel]{}
+		repo.Init(db, nil)
+
+		id1 := uuid.New()
+		id2 := uuid.New()
+		id3 := uuid.New()
+		cnt := 3456
+		filter := MyModelFilter{
+			Ids:   &[]uuid.UUID{id1, id2, id3},
+			CntGT: &cnt,
+		}
+
+		sql := "DELETE FROM my_models WHERE my_models.id IN ($1,$2,$3) AND my_models.cnt > $4"
+		mock.ExpectBegin()
+		mock.ExpectExec(fmt.Sprintf("^%s$", regexp.QuoteMeta(sql))).
+			WithArgs(id1, id2, id3, cnt).
+			WillReturnResult(sqlmock.NewResult(1, 123))
+		mock.ExpectCommit()
+
+		deleted, err := repo.Delete(filter)
+		assert.Equal(t, int64(123), deleted)
+		assert.Nil(t, err)
+
+		if err := mock.ExpectationsWereMet(); err != nil {
+			t.Errorf("there were unfulfilled expectations: %s", err)
+		}
+	})
+}

app/repository/method_list_test.go

@@ -33,9 +33,9 @@ func NewMockDB() (*sql.DB, *gorm.DB, sqlmock.Sqlmock) {
 }
 
 type MyModel struct {
-	Id    uuid.UUID
+	Id    *uuid.UUID `gorm:"type(uuid);unique"`
 	Value string
-	Count int
+	Cnt   int
 }
 
 func (m MyModel) TableName() string {
@@ -43,10 +43,10 @@ func (m MyModel) TableName() string {
 }
 
 type MyModelFilter struct {
-	Id    *uuid.UUID   `filterfield:"field=id,operator=EQ"`
-	Ids   *[]uuid.UUID `filterfield:"field=id,operator=IN"`
-	Value *string      `filterfield:"field=value,operator=EQ"`
-	Count *int         `filterfield:"field=count,operator=GT"`
+	Id    *uuid.UUID   `filterfield:"field=id;operator=EQ"`
+	Ids   *[]uuid.UUID `filterfield:"field=id;operator=IN"`
+	Value *string      `filterfield:"field=value;operator=EQ"`
+	CntGT *int         `filterfield:"field=cnt;operator=GT"`
 }
 
 func TestListMethod(t *testing.T) {
@@ -65,13 +65,13 @@ func TestListMethod(t *testing.T) {
 					Direction: OrderASC,
 				},
 				{
-					Field:     "count",
+					Field:     "cnt",
 					Direction: OrderDESC,
 				},
 			},
 		}
 
-		sql := "SELECT * FROM my_models ORDER BY id,count DESC"
+		sql := "SELECT * FROM my_models ORDER BY id,cnt DESC"
 		mock.ExpectQuery(fmt.Sprintf("^%s$", regexp.QuoteMeta(sql)))
 
 		_, err := repo.List(filter, &options)
@@ -198,10 +198,10 @@ func TestListMethod(t *testing.T) {
 		filter := MyModelFilter{
 			Id:    &id,
 			Value: &value,
-			Count: &count,
+			CntGT: &count,
 		}
 
-		sql := "SELECT * FROM my_models WHERE my_models.id = $1 AND my_models.value = $2 AND my_models.count > $3"
+		sql := "SELECT * FROM my_models WHERE my_models.id = $1 AND my_models.value = $2 AND my_models.cnt > $3"
 		mock.ExpectQuery(fmt.Sprintf("^%s$", regexp.QuoteMeta(sql))).
 			WithArgs(id, value, count)
 
@@ -226,7 +226,7 @@ func TestListMethod(t *testing.T) {
 		filter := MyModelFilter{
 			Id:    &id,
 			Value: &value,
-			Count: &count,
+			CntGT: &count,
 		}
 		options := ListOptions{
 			Pagination: &Pagination{
@@ -235,7 +235,7 @@ func TestListMethod(t *testing.T) {
 			},
 		}
 
-		sql := "SELECT * FROM my_models WHERE my_models.id = $1 AND my_models.value = $2 AND my_models.count > $3 LIMIT $4 OFFSET $5"
+		sql := "SELECT * FROM my_models WHERE my_models.id = $1 AND my_models.value = $2 AND my_models.cnt > $3 LIMIT $4 OFFSET $5"
 		mock.ExpectQuery(fmt.Sprintf("^%s$", regexp.QuoteMeta(sql))).
 			WithArgs(id, value, count, options.Pagination.Limit, options.Pagination.Offset)
 
@@ -258,11 +258,11 @@ func TestListMethod(t *testing.T) {
 		options := ListOptions{
 			Only: &[]string{
 				"id",
-				"count",
+				"cnt",
 			},
 		}
 
-		sql := "SELECT id,count FROM my_models"
+		sql := "SELECT id,cnt FROM my_models"
 		mock.ExpectQuery(fmt.Sprintf("^%s$", regexp.QuoteMeta(sql)))
 
 		_, err := repo.List(filter, &options)

app/repository/method_save.go

@@ -0,0 +1,18 @@
+package repository
+
+import (
+	"gorm.io/gorm/schema"
+)
+
+type SaveMethod[T schema.Tabler] struct {
+	repo *RepoBase[T]
+}
+
+func (m *SaveMethod[T]) Init(repo *RepoBase[T]) {
+	m.repo = repo
+}
+
+func (m SaveMethod[T]) Save(model *T) (*T, error) {
+	result := m.repo.dbConn.Save(model)
+	return model, result.Error
+}

app/repository/method_save_test.go

@@ -0,0 +1,69 @@
+package repository
+
+import (
+	"fmt"
+	"regexp"
+	"testing"
+
+	"github.com/DATA-DOG/go-sqlmock"
+	"github.com/google/uuid"
+	"github.com/stretchr/testify/assert"
+)
+
+func TestSaveMethod(t *testing.T) {
+	t.Run("Save new model", func(t *testing.T) {
+		sqldb, db, mock := NewMockDB()
+		defer sqldb.Close()
+
+		repo := RepoBase[MyModel]{}
+		repo.Init(db, nil)
+
+		model := MyModel{
+			Value: "some value",
+			Cnt:   123,
+		}
+
+		sql := "INSERT INTO my_models (id,value,cnt) VALUES ($1,$2,$3)"
+		mock.ExpectBegin()
+		mock.ExpectExec(fmt.Sprintf("^%s$", regexp.QuoteMeta(sql))).
+			WithArgs(model.Id, model.Value, model.Cnt).
+			WillReturnResult(sqlmock.NewResult(1, 1))
+		mock.ExpectCommit()
+
+		_, err := repo.Save(&model)
+		assert.Nil(t, err)
+
+		if err := mock.ExpectationsWereMet(); err != nil {
+			t.Errorf("there were unfulfilled expectations: %s", err)
+		}
+	})
+
+	t.Run("Update existing model", func(t *testing.T) {
+		sqldb, db, mock := NewMockDB()
+		defer sqldb.Close()
+
+		repo := RepoBase[MyModel]{}
+		repo.Init(db, nil)
+
+		id := uuid.New()
+		model := MyModel{
+			Id:    &id,
+			Value: "some value",
+			Cnt:   123,
+		}
+
+		sql := "UPDATE my_models SET value=$1,cnt=$2 WHERE id = $3"
+		mock.ExpectBegin()
+		mock.ExpectExec(fmt.Sprintf("^%s$", regexp.QuoteMeta(sql))).
+			WithArgs(model.Value, model.Cnt, model.Id).
+			WillReturnResult(sqlmock.NewResult(1, 1))
+		mock.ExpectCommit()
+
+		_, err := repo.Save(&model)
+		assert.Nil(t, err)
+
+		if err := mock.ExpectationsWereMet(); err != nil {
+			t.Errorf("there were unfulfilled expectations: %s", err)
+		}
+	})
+}

app/repository/method_update.go

@@ -0,0 +1,31 @@
+package repository
+
+import (
+	"repo-pattern/app/repository/smartfilter"
+
+	"gorm.io/gorm/schema"
+)
+
+type UpdateMethod[T schema.Tabler] struct {
+	repo *RepoBase[T]
+}
+
+func (m *UpdateMethod[T]) Init(repo *RepoBase[T]) {
+	m.repo = repo
+}
+
+func (m UpdateMethod[T]) Update(filter interface{}, values map[string]any) (int64, error) {
+	var (
+		model T
+	)
+
+	query, err := smartfilter.ToQuery(model, filter, m.repo.dbConn)
+	if err != nil {
+		return 0, err
+	}
+	result := query.Model(&model).Updates(values)
+	if result.Error != nil {
+		return 0, result.Error
+	}
+	return result.RowsAffected, nil
+}

app/repository/method_update_test.go

@@ -0,0 +1,43 @@
+package repository
+
+import (
+	"fmt"
+	"regexp"
+	"testing"
+
+	"github.com/DATA-DOG/go-sqlmock"
+	"github.com/stretchr/testify/assert"
+)
+
+func TestUpdateMethod(t *testing.T) {
+	t.Run("Update", func(t *testing.T) {
+		sqldb, db, mock := NewMockDB()
+		defer sqldb.Close()
+
+		repo := RepoBase[MyModel]{}
+		repo.Init(db, nil)
+
+		cnt := 10
+		filter := MyModelFilter{
+			CntGT: &cnt,
+		}
+		values := map[string]any{
+			"cnt":   111,
+			"value": 222,
+		}
+
+		sql := "UPDATE my_models SET cnt=$1,value=$2 WHERE my_models.cnt > $3"
+		mock.ExpectBegin()
+		mock.ExpectExec(fmt.Sprintf("^%s$", regexp.QuoteMeta(sql))).
+			WithArgs(values["cnt"], values["value"], cnt).
+			WillReturnResult(sqlmock.NewResult(1, 1))
+		mock.ExpectCommit()
+
+		_, err := repo.Update(filter, values)
+		assert.Nil(t, err)
+
+		if err := mock.ExpectationsWereMet(); err != nil {
+			t.Errorf("there were unfulfilled expectations: %s", err)
+		}
+	})
+}

app/repository/repository.go

@@ -5,6 +5,8 @@ import (
 	"gorm.io/gorm/schema"
 )
 
+const DEFAULT_ID_FIELD = "id"
+
 type MethodInitInterface[T schema.Tabler] interface {
 	Init(repo *RepoBase[T])
 }
@@ -21,11 +23,13 @@ type RepoBase[T schema.Tabler] struct {
 	GetMethod[T]
 	ExistsMethod[T]
 	CountMethod[T]
-	methods []MethodInitInterface[T]
+	SaveMethod[T]
+	UpdateMethod[T]
+	DeleteMethod[T]
 }
 
-func (repo *RepoBase[T]) InitMethods() {
-	for _, method := range repo.methods {
+func (repo *RepoBase[T]) InitMethods(methods []MethodInitInterface[T]) {
+	for _, method := range methods {
 		method.Init(repo)
 	}
 }
@@ -35,18 +39,21 @@ func (m *RepoBase[T]) Init(dbConn *gorm.DB, options *RepoOptions) {
 
 	if options == nil {
 		// no options provided? set defaults
-		m.IdField = "id"
+		m.IdField = DEFAULT_ID_FIELD
 	} else {
 		if len(options.IdField) > 0 {
 			m.IdField = options.IdField
 		}
 	}
 
-	m.methods = []MethodInitInterface[T]{
+	methods := []MethodInitInterface[T]{
 		&m.ListMethod,
 		&m.GetMethod,
 		&m.ExistsMethod,
 		&m.CountMethod,
+		&m.SaveMethod,
+		&m.UpdateMethod,
+		&m.DeleteMethod,
 	}
-	m.InitMethods()
+	m.InitMethods(methods)
 }

app/repository/smartfilter/smartfilter.go

@@ -11,11 +11,16 @@ import (
 )
 
 const TAG_NAME = "filterfield"
-const TAG_PAIRS_SEPARATOR = ","
+const TAG_PAIRS_SEPARATOR = ";"
+const TAG_LIST_SEPARATOR = ","
 const TAG_KEYVALUE_SEPARATOR = "="
 
 type handlerFunc func(query *gorm.DB, tableName string, filterField *FilterField) *gorm.DB
 
+type QueryApplier interface {
+	ApplyQuery(query *gorm.DB) *gorm.DB
+}
+
 var operatorHandlers = map[Operator]handlerFunc{
 	OperatorEQ:     handleOperatorEQ,
 	OperatorNE:     handleOperatorNE,
@@ -67,15 +72,20 @@ func getFilterFields(filter interface{}) []ReflectedStructField {
 	return res
 }
 
+func getQueryApplierInterface(filter interface{}) QueryApplier {
+	queryApplier, ok := filter.(QueryApplier)
+	if ok {
+		return queryApplier
+	}
+	return nil
+}
+
 func ToQuery(model schema.Tabler, filter interface{}, query *gorm.DB) (*gorm.DB, error) {
 	st := reflect.TypeOf(filter)
 
 	tableName := model.TableName()
 	modelName := st.Name()
 
-	fmt.Printf("Table name: %s\n", tableName)
-	fmt.Printf("Model name: %s\n", modelName)
-
 	fields := getFilterFields(filter)
 	for _, field := range fields {
 		filterField, err := newFilterField(field.tagValue)
@@ -97,22 +107,36 @@ func ToQuery(model schema.Tabler, filter interface{}, query *gorm.DB) (*gorm.DB,
 		}
 	}
 
+	// apply custom filters, if interface exists
+	queryApplier := getQueryApplierInterface(filter)
+	if queryApplier != nil {
+		query = queryApplier.ApplyQuery(query)
+	}
+
 	return query, nil
 }
 
+func splitTrim(value string, separator string) []string {
+	var out []string = []string{}
+	for _, s := range strings.Split(value, separator) {
+		if len(s) == 0 {
+			continue
+		}
+		out = append(out, strings.TrimSpace(s))
+	}
+	return out
+}
+
 func newFilterField(tagValue string) (*FilterField, error) {
 	filterField := FilterField{}
 
-	tagValue = strings.TrimSpace(tagValue)
-	pairs := strings.Split(tagValue, TAG_PAIRS_SEPARATOR)
-
-	for _, pair := range pairs {
-		kvs := strings.Split(pair, TAG_KEYVALUE_SEPARATOR)
+	for _, pair := range splitTrim(tagValue, TAG_PAIRS_SEPARATOR) {
+		kvs := splitTrim(pair, TAG_KEYVALUE_SEPARATOR)
 		if len(kvs) != 2 {
 			return nil, fmt.Errorf("invalid tag value: %s", strings.TrimSpace(pair))
 		}
-		key := strings.TrimSpace(kvs[0])
-		value := strings.TrimSpace(kvs[1])
+		key := kvs[0]
+		value := kvs[1]
 
 		switch key {
 		case "field":

app/repository/smartfilter/smartfilter_test.go

@@ -6,6 +6,7 @@ import (
 	"time"
 
 	"github.com/stretchr/testify/assert"
+	"gorm.io/gorm"
 )
 
 func TestGetFilterFields(t *testing.T) {
@@ -101,11 +102,11 @@ func TestGetFilterFields(t *testing.T) {
 
 	t.Run("Skip nil fields", func(t *testing.T) {
 		type TestFilter struct {
-			Alive     *bool   `filterfield:"alive,EQ"`
-			Id        *int64  `filterfield:"id,EQ"`
-			Ids       *[]uint `filterfield:"id,IN"`
-			IdsNot    *[]uint `filterfield:"id,NOT_IN"`
-			FirstName *string `filterfield:"first_name,EQ"`
+			Alive     *bool   `filterfield:"alive;EQ"`
+			Id        *int64  `filterfield:"id;EQ"`
+			Ids       *[]uint `filterfield:"id;IN"`
+			IdsNot    *[]uint `filterfield:"id;NOT_IN"`
+			FirstName *string `filterfield:"first_name;EQ"`
 		}
 		filter := TestFilter{}
 		result := getFilterFields(filter)
@@ -119,7 +120,7 @@ func TestGetFilterFields(t *testing.T) {
 		)
 		type TestFilter struct {
 			Alive *bool
-			Id    *int64 `funnytag:"created_at,LT"`
+			Id    *int64 `funnytag:"created_at;LT"`
 		}
 		filter := TestFilter{
 			Alive: &alive,
@@ -140,7 +141,7 @@ func TestFilterField(t *testing.T) {
 	testCases := []TagParseTestCase{
 		{
 			name:     "Parse without spaces",
-			tagValue: "field=field_1,operator=EQ",
+			tagValue: "field=field_1;operator=EQ",
 			expected: FilterField{
 				Name:     "field_1",
 				Operator: OperatorEQ,
@@ -148,7 +149,7 @@ func TestFilterField(t *testing.T) {
 		},
 		{
 			name:     "Parse spaces between pairs",
-			tagValue: "   field=field_2 ,   operator=LT   ",
+			tagValue: "   field=field_2 ;   operator=LT   ",
 			expected: FilterField{
 				Name:     "field_2",
 				Operator: OperatorLT,
@@ -156,7 +157,7 @@ func TestFilterField(t *testing.T) {
 		},
 		{
 			name:     "Parse spaces between around keys and values",
-			tagValue: "operator   = LIKE , field = field_3",
+			tagValue: "operator   = LIKE ; field = field_3",
 			expected: FilterField{
 				Name:     "field_3",
 				Operator: OperatorLIKE,
@@ -174,19 +175,19 @@ func TestFilterField(t *testing.T) {
 	}
 
 	t.Run("Fail on invalid tag value", func(t *testing.T) {
-		filterField, err := newFilterField("field=field_1=fail, operator=EQ")
+		filterField, err := newFilterField("field=field_1=fail; operator=EQ")
 		assert.Nil(t, filterField)
 		assert.EqualError(t, err, "invalid tag value: field=field_1=fail")
 	})
 
 	t.Run("Fail on invalid operator", func(t *testing.T) {
-		filterField, err := newFilterField("field=field_1, operator=FAIL")
+		filterField, err := newFilterField("field=field_1; operator=FAIL")
 		assert.Nil(t, filterField)
 		assert.EqualError(t, err, "unknown operator: FAIL")
 	})
 
 	t.Run("Fail on invalid value key", func(t *testing.T) {
-		filterField, err := newFilterField("failkey=field_1, operator=FAIL")
+		filterField, err := newFilterField("failkey=field_1; operator=FAIL")
 		assert.Nil(t, filterField)
 		assert.EqualError(t, err, "invalid value key: failkey")
 	})
@@ -203,3 +204,26 @@ func TestFilterField(t *testing.T) {
 		assert.EqualError(t, err, "missing operator in tag: field=field_1")
 	})
 }
+
+type filterWithoutQueryApplier struct{}
+
+type filterWithQueryApplier struct{}
+
+func (f filterWithQueryApplier) ApplyQuery(query *gorm.DB) *gorm.DB {
+	return query
+}
+
+func TestSmartfilterApplyQuery(t *testing.T) {
+
+	t.Run("Get query applier interface - without interface", func(t *testing.T) {
+		f := filterWithoutQueryApplier{}
+		queryApplier := getQueryApplierInterface(f)
+		assert.Nil(t, queryApplier)
+	})
+
+	t.Run("Get query applier interface - with interface", func(t *testing.T) {
+		f := filterWithQueryApplier{}
+		queryApplier := getQueryApplierInterface(f)
+		assert.NotNil(t, queryApplier)
+	})
+}