Db service fixes and improvements: dot access, truncate table etc (#157)

db/handler/db.go

@@ -22,6 +22,7 @@ import (
 
 const idKey = "id"
 const stmt = "create table if not exists %v(id text not null, data jsonb, primary key(id)); alter table %v add created_at timestamptz; alter table %v add updated_at timestamptz"
+const truncateStmt = `truncate table "%v"`
 
 var re = regexp.MustCompile("^[a-zA-Z0-9_]*$")
 var c = cache.New(5*time.Minute, 10*time.Minute)
@@ -39,6 +40,23 @@ type Db struct {
 	gorm2.Helper
 }
 
+func correctFieldName(s string) string {
+	switch s {
+	// top level fields can stay top level
+	case "id": // "created_at", "updated_at",  <-- these are not special fields for now
+		return s
+	}
+	if !strings.Contains(s, ".") {
+		return fmt.Sprintf("data ->> '%v'", s)
+	}
+	paths := strings.Split(s, ".")
+	ret := "data"
+	for _, path := range paths {
+		ret += fmt.Sprintf(" ->> '%v'", path)
+	}
+	return ret
+}
+
 // Call is a single request handler called via client.Call or the generated client code
 func (e *Db) Create(ctx context.Context, req *db.CreateRequest, rsp *db.CreateResponse) error {
 	if len(req.Record.AsMap()) == 0 {
@@ -208,13 +226,28 @@ func (e *Db) Read(ctx context.Context, req *db.ReadRequest, rsp *db.ReadResponse
 		case itemNotEquals:
 			op = "!="
 		}
-		db = db.Where(fmt.Sprintf("(data ->> '%v')::%v %v ?", query.Field, typ, op), query.Value)
+		queryField := correctFieldName(query.Field)
+		db = db.Where(fmt.Sprintf("(%v)::%v %v ?", queryField, typ, op), query.Value)
 	}
-	orderField := "created_at DESC"
+	orderField := "created_at"
 	if req.OrderBy != "" {
-		orderField = req.OrderBy + " " + req.Order
+		orderField = req.OrderBy
 	}
-	db = db.Order(orderField).Offset(int(req.Offset)).Limit(int(req.Limit))
+	orderField = correctFieldName(orderField)
+
+	ordering := "asc"
+	if req.Order != "" {
+		switch strings.ToLower(req.Order) {
+		case "asc":
+			ordering = "asc"
+		case "", "desc":
+			ordering = "desc"
+		default:
+			return errors.BadRequest("db.read", "invalid ordering: "+req.Order)
+		}
+	}
+
+	db = db.Order(orderField + " " + ordering).Offset(int(req.Offset)).Limit(int(req.Limit))
 	err = db.Find(&recs).Error
 	if err != nil {
 		return err
@@ -269,3 +302,25 @@ func (e *Db) Delete(ctx context.Context, req *db.DeleteRequest, rsp *db.DeleteRe
 		ID: req.Id,
 	}).Error
 }
+
+func (e *Db) Truncate(ctx context.Context, req *db.TruncateRequest, rsp *db.TruncateResponse) error {
+	tenantId, ok := tenant.FromContext(ctx)
+	if !ok {
+		tenantId = "micro"
+	}
+	if req.Table == "" {
+		req.Table = "default"
+	}
+	tenantId = strings.Replace(strings.Replace(tenantId, "/", "_", -1), "-", "_", -1)
+	tableName := tenantId + "_" + req.Table
+	if !re.Match([]byte(tableName)) {
+		return errors.BadRequest("db.create", fmt.Sprintf("table name %v is invalid", req.Table))
+	}
+	logger.Infof("Truncating table '%v'", tableName)
+
+	db, err := e.GetDBConn(ctx)
+	if err != nil {
+		return err
+	}
+	return db.Exec(fmt.Sprintf(truncateStmt, tableName)).Error
+}

db/handler/parse.go

@@ -57,7 +57,7 @@ var expressions = []lexer.TokenExpr{
 	{`"(?:[^"\\]|\\.)*"`, itemString},
 	{"`" + `(?:[^"\\]|\\.)*` + "`", itemString},
 	{`'(?:[^"\\]|\\.)*'`, itemString},
-	{`[\<\>\!\=\+\-\|\&\*\/A-Za-z][A-Za-z0-9_]*`, itemFieldName},
+	{`[\<\>\!\=\+\-\|\&\*\/A-Za-z][A-Za-z0-9_\.]*`, itemFieldName},
 }
 
 type Query struct {

db/handler/parse_test.go

@@ -8,6 +8,13 @@ import (
 	"github.com/crufter/lexer"
 )
 
+func TestCorrectFieldName(t *testing.T) {
+	f := correctFieldName("a.b.c")
+	if f != "data ->> 'a' ->> 'b' ->> 'c'" {
+		t.Fatal(f)
+	}
+}
+
 func TestLexing(t *testing.T) {
 	tokens, err := lexer.Lex("a == 12", expressions)
 	if err != nil {
@@ -55,6 +62,21 @@ func TestParsing(t *testing.T) {
 				},
 			},
 		},
+		tCase{
+			Q: `a.b.c == 12 and name != "nandos"`,
+			E: []Query{
+				Query{
+					Field: "a.b.c",
+					Value: int64(12),
+					Op:    itemEquals,
+				},
+				Query{
+					Field: "name",
+					Value: "nandos",
+					Op:    itemNotEquals,
+				},
+			},
+		},
 		tCase{
 			Q: `a == 12 and name != "nan'dos"`,
 			E: []Query{

db/proto/db.pb.go

@@ -27,16 +27,22 @@ type ReadRequest struct {
 	unknownFields protoimpl.UnknownFields
 
 	Table string `protobuf:"bytes,1,opt,name=table,proto3" json:"table,omitempty"`
-	// eg. 'age >= 18', 'age >= 18 and verified == true'
+	// Read by id. Equivalent to 'id == "your-id"'
-	// comparison operators: '==', '!=', '<', '>', '<=', '>='
+	Id string `protobuf:"bytes,2,opt,name=id,proto3" json:"id,omitempty"`
-	// logical operator: 'and'
+	// Examples: 'age >= 18', 'age >= 18 and verified == true'
-	Query  string `protobuf:"bytes,2,opt,name=query,proto3" json:"query,omitempty"`
+	// Comparison operators: '==', '!=', '<', '>', '<=', '>='
-	Offset int32  `protobuf:"varint,3,opt,name=offset,proto3" json:"offset,omitempty"`
+	// Logical operator: 'and'
-	Limit  int32  `protobuf:"varint,4,opt,name=limit,proto3" json:"limit,omitempty"`
+	// Dot access is supported, eg: 'user.age == 11'
+	// Accessing list elements is not supported yet.
+	Query  string `protobuf:"bytes,3,opt,name=query,proto3" json:"query,omitempty"`
+	Offset int32  `protobuf:"varint,4,opt,name=offset,proto3" json:"offset,omitempty"`
+	// Default limit is 25.
+	// Maximum limit is 1000. Anything higher will return an error.
+	Limit int32 `protobuf:"varint,5,opt,name=limit,proto3" json:"limit,omitempty"`
 	// field name to order by
-	OrderBy string `protobuf:"bytes,5,opt,name=orderBy,proto3" json:"orderBy,omitempty"`
+	OrderBy string `protobuf:"bytes,6,opt,name=orderBy,proto3" json:"orderBy,omitempty"`
 	// 'asc' (default), 'desc'
-	Order string `protobuf:"bytes,6,opt,name=order,proto3" json:"order,omitempty"`
+	Order string `protobuf:"bytes,7,opt,name=order,proto3" json:"order,omitempty"`
 }
 
 func (x *ReadRequest) Reset() {
@@ -78,6 +84,13 @@ func (x *ReadRequest) GetTable() string {
 	return ""
 }
 
+func (x *ReadRequest) GetId() string {
+	if x != nil {
+		return x.Id
+	}
+	return ""
+}
+
 func (x *ReadRequest) GetQuery() string {
 	if x != nil {
 		return x.Query
@@ -453,22 +466,117 @@ func (*DeleteResponse) Descriptor() ([]byte, []int) {
 	return file_proto_db_proto_rawDescGZIP(), []int{7}
 }
 
+type TruncateRequest struct {
+	state         protoimpl.MessageState
+	sizeCache     protoimpl.SizeCache
+	unknownFields protoimpl.UnknownFields
+
+	Table string `protobuf:"bytes,1,opt,name=table,proto3" json:"table,omitempty"`
+}
+
+func (x *TruncateRequest) Reset() {
+	*x = TruncateRequest{}
+	if protoimpl.UnsafeEnabled {
+		mi := &file_proto_db_proto_msgTypes[8]
+		ms := protoimpl.X.MessageStateOf(protoimpl.Pointer(x))
+		ms.StoreMessageInfo(mi)
+	}
+}
+
+func (x *TruncateRequest) String() string {
+	return protoimpl.X.MessageStringOf(x)
+}
+
+func (*TruncateRequest) ProtoMessage() {}
+
+func (x *TruncateRequest) ProtoReflect() protoreflect.Message {
+	mi := &file_proto_db_proto_msgTypes[8]
+	if protoimpl.UnsafeEnabled && x != nil {
+		ms := protoimpl.X.MessageStateOf(protoimpl.Pointer(x))
+		if ms.LoadMessageInfo() == nil {
+			ms.StoreMessageInfo(mi)
+		}
+		return ms
+	}
+	return mi.MessageOf(x)
+}
+
+// Deprecated: Use TruncateRequest.ProtoReflect.Descriptor instead.
+func (*TruncateRequest) Descriptor() ([]byte, []int) {
+	return file_proto_db_proto_rawDescGZIP(), []int{8}
+}
+
+func (x *TruncateRequest) GetTable() string {
+	if x != nil {
+		return x.Table
+	}
+	return ""
+}
+
+type TruncateResponse struct {
+	state         protoimpl.MessageState
+	sizeCache     protoimpl.SizeCache
+	unknownFields protoimpl.UnknownFields
+
+	Table string `protobuf:"bytes,1,opt,name=table,proto3" json:"table,omitempty"`
+}
+
+func (x *TruncateResponse) Reset() {
+	*x = TruncateResponse{}
+	if protoimpl.UnsafeEnabled {
+		mi := &file_proto_db_proto_msgTypes[9]
+		ms := protoimpl.X.MessageStateOf(protoimpl.Pointer(x))
+		ms.StoreMessageInfo(mi)
+	}
+}
+
+func (x *TruncateResponse) String() string {
+	return protoimpl.X.MessageStringOf(x)
+}
+
+func (*TruncateResponse) ProtoMessage() {}
+
+func (x *TruncateResponse) ProtoReflect() protoreflect.Message {
+	mi := &file_proto_db_proto_msgTypes[9]
+	if protoimpl.UnsafeEnabled && x != nil {
+		ms := protoimpl.X.MessageStateOf(protoimpl.Pointer(x))
+		if ms.LoadMessageInfo() == nil {
+			ms.StoreMessageInfo(mi)
+		}
+		return ms
+	}
+	return mi.MessageOf(x)
+}
+
+// Deprecated: Use TruncateResponse.ProtoReflect.Descriptor instead.
+func (*TruncateResponse) Descriptor() ([]byte, []int) {
+	return file_proto_db_proto_rawDescGZIP(), []int{9}
+}
+
+func (x *TruncateResponse) GetTable() string {
+	if x != nil {
+		return x.Table
+	}
+	return ""
+}
+
 var File_proto_db_proto protoreflect.FileDescriptor
 
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+	0x75, 0x6e, 0x63, 0x61, 0x74, 0x65, 0x52, 0x65, 0x71, 0x75, 0x65, 0x73, 0x74, 0x1a, 0x14, 0x2e,
+	0x64, 0x62, 0x2e, 0x54, 0x72, 0x75, 0x6e, 0x63, 0x61, 0x74, 0x65, 0x52, 0x65, 0x73, 0x70, 0x6f,
+	0x6e, 0x73, 0x65, 0x22, 0x00, 0x42, 0x0c, 0x5a, 0x0a, 0x2e, 0x2f, 0x70, 0x72, 0x6f, 0x74, 0x6f,
+	0x3b, 0x64, 0x62, 0x62, 0x06, 0x70, 0x72, 0x6f, 0x74, 0x6f, 0x33,
 }
 
 var (
@@ -520,35 +637,39 @@ func file_proto_db_proto_rawDescGZIP() []byte {
 	return file_proto_db_proto_rawDescData
 }
 
-var file_proto_db_proto_msgTypes = make([]protoimpl.MessageInfo, 8)
+var file_proto_db_proto_msgTypes = make([]protoimpl.MessageInfo, 10)
 var file_proto_db_proto_goTypes = []interface{}{
-	(*ReadRequest)(nil),    // 0: db.ReadRequest
+	(*ReadRequest)(nil),      // 0: db.ReadRequest
-	(*ReadResponse)(nil),   // 1: db.ReadResponse
+	(*ReadResponse)(nil),     // 1: db.ReadResponse
-	(*CreateRequest)(nil),  // 2: db.CreateRequest
+	(*CreateRequest)(nil),    // 2: db.CreateRequest
-	(*CreateResponse)(nil), // 3: db.CreateResponse
+	(*CreateResponse)(nil),   // 3: db.CreateResponse
-	(*UpdateRequest)(nil),  // 4: db.UpdateRequest
+	(*UpdateRequest)(nil),    // 4: db.UpdateRequest
-	(*UpdateResponse)(nil), // 5: db.UpdateResponse
+	(*UpdateResponse)(nil),   // 5: db.UpdateResponse
-	(*DeleteRequest)(nil),  // 6: db.DeleteRequest
+	(*DeleteRequest)(nil),    // 6: db.DeleteRequest
-	(*DeleteResponse)(nil), // 7: db.DeleteResponse
+	(*DeleteResponse)(nil),   // 7: db.DeleteResponse
-	(*_struct.Struct)(nil), // 8: google.protobuf.Struct
+	(*TruncateRequest)(nil),  // 8: db.TruncateRequest
+	(*TruncateResponse)(nil), // 9: db.TruncateResponse
+	(*_struct.Struct)(nil),   // 10: google.protobuf.Struct
 }
 var file_proto_db_proto_depIdxs = []int32{
-	8, // 0: db.ReadResponse.records:type_name -> google.protobuf.Struct
+	10, // 0: db.ReadResponse.records:type_name -> google.protobuf.Struct
-	8, // 1: db.CreateRequest.record:type_name -> google.protobuf.Struct
+	10, // 1: db.CreateRequest.record:type_name -> google.protobuf.Struct
-	8, // 2: db.UpdateRequest.record:type_name -> google.protobuf.Struct
+	10, // 2: db.UpdateRequest.record:type_name -> google.protobuf.Struct
-	2, // 3: db.Db.Create:input_type -> db.CreateRequest
+	2,  // 3: db.Db.Create:input_type -> db.CreateRequest
-	0, // 4: db.Db.Read:input_type -> db.ReadRequest
+	0,  // 4: db.Db.Read:input_type -> db.ReadRequest
-	4, // 5: db.Db.Update:input_type -> db.UpdateRequest
+	4,  // 5: db.Db.Update:input_type -> db.UpdateRequest
-	6, // 6: db.Db.Delete:input_type -> db.DeleteRequest
+	6,  // 6: db.Db.Delete:input_type -> db.DeleteRequest
-	3, // 7: db.Db.Create:output_type -> db.CreateResponse
+	8,  // 7: db.Db.Truncate:input_type -> db.TruncateRequest
-	1, // 8: db.Db.Read:output_type -> db.ReadResponse
+	3,  // 8: db.Db.Create:output_type -> db.CreateResponse
-	5, // 9: db.Db.Update:output_type -> db.UpdateResponse
+	1,  // 9: db.Db.Read:output_type -> db.ReadResponse
-	7, // 10: db.Db.Delete:output_type -> db.DeleteResponse
+	5,  // 10: db.Db.Update:output_type -> db.UpdateResponse
-	7, // [7:11] is the sub-list for method output_type
+	7,  // 11: db.Db.Delete:output_type -> db.DeleteResponse
-	3, // [3:7] is the sub-list for method input_type
+	9,  // 12: db.Db.Truncate:output_type -> db.TruncateResponse
-	3, // [3:3] is the sub-list for extension type_name
+	8,  // [8:13] is the sub-list for method output_type
-	3, // [3:3] is the sub-list for extension extendee
+	3,  // [3:8] is the sub-list for method input_type
-	0, // [0:3] is the sub-list for field type_name
+	3,  // [3:3] is the sub-list for extension type_name
+	3,  // [3:3] is the sub-list for extension extendee
+	0,  // [0:3] is the sub-list for field type_name
 }
 
 func init() { file_proto_db_proto_init() }
@@ -653,6 +774,30 @@ func file_proto_db_proto_init() {
 				return nil
 			}
 		}
+		file_proto_db_proto_msgTypes[8].Exporter = func(v interface{}, i int) interface{} {
+			switch v := v.(*TruncateRequest); i {
+			case 0:
+				return &v.state
+			case 1:
+				return &v.sizeCache
+			case 2:
+				return &v.unknownFields
+			default:
+				return nil
+			}
+		}
+		file_proto_db_proto_msgTypes[9].Exporter = func(v interface{}, i int) interface{} {
+			switch v := v.(*TruncateResponse); i {
+			case 0:
+				return &v.state
+			case 1:
+				return &v.sizeCache
+			case 2:
+				return &v.unknownFields
+			default:
+				return nil
+			}
+		}
 	}
 	type x struct{}
 	out := protoimpl.TypeBuilder{
@@ -660,7 +805,7 @@ func file_proto_db_proto_init() {
 			GoPackagePath: reflect.TypeOf(x{}).PkgPath(),
 			RawDescriptor: file_proto_db_proto_rawDesc,
 			NumEnums:      0,
-			NumMessages:   8,
+			NumMessages:   10,
 			NumExtensions: 0,
 			NumServices:   1,
 		},

db/proto/db.pb.micro.go

@@ -47,6 +47,7 @@ type DbService interface {
 	Read(ctx context.Context, in *ReadRequest, opts ...client.CallOption) (*ReadResponse, error)
 	Update(ctx context.Context, in *UpdateRequest, opts ...client.CallOption) (*UpdateResponse, error)
 	Delete(ctx context.Context, in *DeleteRequest, opts ...client.CallOption) (*DeleteResponse, error)
+	Truncate(ctx context.Context, in *TruncateRequest, opts ...client.CallOption) (*TruncateResponse, error)
 }
 
 type dbService struct {
@@ -101,6 +102,16 @@ func (c *dbService) Delete(ctx context.Context, in *DeleteRequest, opts ...clien
 	return out, nil
 }
 
+func (c *dbService) Truncate(ctx context.Context, in *TruncateRequest, opts ...client.CallOption) (*TruncateResponse, error) {
+	req := c.c.NewRequest(c.name, "Db.Truncate", in)
+	out := new(TruncateResponse)
+	err := c.c.Call(ctx, req, out, opts...)
+	if err != nil {
+		return nil, err
+	}
+	return out, nil
+}
+
 // Server API for Db service
 
 type DbHandler interface {
@@ -108,6 +119,7 @@ type DbHandler interface {
 	Read(context.Context, *ReadRequest, *ReadResponse) error
 	Update(context.Context, *UpdateRequest, *UpdateResponse) error
 	Delete(context.Context, *DeleteRequest, *DeleteResponse) error
+	Truncate(context.Context, *TruncateRequest, *TruncateResponse) error
 }
 
 func RegisterDbHandler(s server.Server, hdlr DbHandler, opts ...server.HandlerOption) error {
@@ -116,6 +128,7 @@ func RegisterDbHandler(s server.Server, hdlr DbHandler, opts ...server.HandlerOp
 		Read(ctx context.Context, in *ReadRequest, out *ReadResponse) error
 		Update(ctx context.Context, in *UpdateRequest, out *UpdateResponse) error
 		Delete(ctx context.Context, in *DeleteRequest, out *DeleteResponse) error
+		Truncate(ctx context.Context, in *TruncateRequest, out *TruncateResponse) error
 	}
 	type Db struct {
 		db
@@ -143,3 +156,7 @@ func (h *dbHandler) Update(ctx context.Context, in *UpdateRequest, out *UpdateRe
 func (h *dbHandler) Delete(ctx context.Context, in *DeleteRequest, out *DeleteResponse) error {
 	return h.DbHandler.Delete(ctx, in, out)
 }
+
+func (h *dbHandler) Truncate(ctx context.Context, in *TruncateRequest, out *TruncateResponse) error {
+	return h.DbHandler.Truncate(ctx, in, out)
+}

db/proto/db.proto

@@ -10,21 +10,28 @@ service Db {
 	rpc Read(ReadRequest) returns (ReadResponse) {}
 	rpc Update(UpdateRequest) returns (UpdateResponse) {}
 	rpc Delete(DeleteRequest) returns (DeleteResponse) {}
+	rpc Truncate(TruncateRequest) returns (TruncateResponse) {}
 }
 
 
 message ReadRequest {
 	string table = 1;
-	// eg. 'age >= 18', 'age >= 18 and verified == true'
+	// Read by id. Equivalent to 'id == "your-id"'
-	// comparison operators: '==', '!=', '<', '>', '<=', '>='
+	string id = 2;
-	// logical operator: 'and'
+	// Examples: 'age >= 18', 'age >= 18 and verified == true'
-	string query = 2;
+	// Comparison operators: '==', '!=', '<', '>', '<=', '>='
-	int32 offset = 3;
+	// Logical operator: 'and'
-	int32 limit = 4;
+	// Dot access is supported, eg: 'user.age == 11'
+	// Accessing list elements is not supported yet.
+	string query = 3;
+	int32 offset = 4;
+	// Default limit is 25.
+	// Maximum limit is 1000. Anything higher will return an error.
+	int32 limit = 5;
 	// field name to order by
-	string orderBy = 5;
+	string orderBy = 6;
 	// 'asc' (default), 'desc'
-	string order = 6;
+	string order = 7;
 }
 
 message ReadResponse {
@@ -62,3 +69,11 @@ message DeleteRequest {
 message DeleteResponse {
 
 }
+
+message TruncateRequest {
+	string table = 1;
+}
+
+message TruncateResponse {
+	string table = 1;
+}