add error statement for context

pkg/response/response.go

@@ -0,0 +1,152 @@
+package response
+
+import (
+	"context"
+	"encoding/json"
+	"fmt"
+	"strings"
+)
+
+type ErrorType string
+
+const (
+	SchemaValidationErrorType ErrorType = "SCHEMA_VALIDATION_ERROR"
+	InvalidRequestErrorType   ErrorType = "INVALID_REQUEST"
+)
+
+type BecknRequest struct {
+	Context map[string]interface{} `json:"context,omitempty"`
+}
+type Error struct {
+	Code    string `json:"code,omitempty"`
+	Message string `json:"message,omitempty"`
+	Paths   string `json:"paths,omitempty"`
+}
+
+// SchemaValidationErr represents a collection of schema validation failures.
+type SchemaValidationErr struct {
+	Errors []Error
+}
+
+// Error implements the error interface for SchemaValidationErr.
+func (e *SchemaValidationErr) Error() string {
+	var errorMessages []string
+	for _, err := range e.Errors {
+		errorMessages = append(errorMessages, fmt.Sprintf("%s: %s", err.Paths, err.Message))
+	}
+	return strings.Join(errorMessages, "; ")
+}
+
+type Message struct {
+	Ack struct {
+		Status string `json:"status,omitempty"`
+	} `json:"ack,omitempty"`
+	Error *Error `json:"error,omitempty"`
+}
+type BecknResponse struct {
+	Context map[string]interface{} `json:"context,omitempty"`
+	Message Message                `json:"message,omitempty"`
+}
+type ClientFailureBecknResponse struct {
+	Context map[string]interface{} `json:"context,omitempty"`
+	Error   *Error                 `json:"error,omitempty"`
+}
+
+var errorMap = map[ErrorType]Error{
+	SchemaValidationErrorType: {
+		Code:    "400",
+		Message: "Schema validation failed",
+	},
+	InvalidRequestErrorType: {
+		Code:    "401",
+		Message: "Invalid request format",
+	},
+}
+var DefaultError = Error{
+	Code:    "500",
+	Message: "Internal server error",
+}
+
+func Nack(ctx context.Context, tp ErrorType, paths string, body []byte) ([]byte, error) {
+	var req BecknRequest
+	if err := json.Unmarshal(body, &req); err != nil {
+		return nil, fmt.Errorf("failed to parse request: %w", err)
+	}
+	errorObj, ok := errorMap[tp]
+	if paths != "" {
+		errorObj.Paths = paths
+	}
+	var response BecknResponse
+	if !ok {
+		response = BecknResponse{
+			Context: req.Context,
+			Message: Message{
+				Ack: struct {
+					Status string `json:"status,omitempty"`
+				}{
+					Status: "NACK",
+				},
+				Error: &DefaultError,
+			},
+		}
+	} else {
+		response = BecknResponse{
+			Context: req.Context,
+			Message: Message{
+				Ack: struct {
+					Status string `json:"status,omitempty"`
+				}{
+					Status: "NACK",
+				},
+				Error: &errorObj,
+			},
+		}
+	}
+	return json.Marshal(response)
+}
+
+// Ack processes the incoming Beckn request, unmarshals the JSON body into a BecknRequest struct,
+// and returns a JSON-encoded acknowledgment response with a status of "ACK".
+// If the request body cannot be parsed, it returns an error.
+func Ack(ctx context.Context, body []byte) ([]byte, error) {
+	var req BecknRequest
+	if err := json.Unmarshal(body, &req); err != nil {
+		return nil, fmt.Errorf("failed to parse request: %w", err)
+	}
+	response := BecknResponse{
+		Context: req.Context,
+		Message: Message{
+			Ack: struct {
+				Status string `json:"status,omitempty"`
+			}{
+				Status: "ACK",
+			},
+		},
+	}
+	return json.Marshal(response)
+}
+
+// HandleClientFailure processes a client failure scenario by unmarshaling the provided
+// request body, determining the appropriate error response based on the given ErrorType,
+// and returning the serialized response. If the ErrorType is not found in the error map,
+// a default error is used.
+func HandleClientFailure(ctx context.Context, tp ErrorType, body []byte) ([]byte, error) {
+	var req BecknRequest
+	if err := json.Unmarshal(body, &req); err != nil {
+		return nil, fmt.Errorf("failed to parse request: %w", err)
+	}
+	errorObj, ok := errorMap[tp]
+	var response ClientFailureBecknResponse
+	if !ok {
+		response = ClientFailureBecknResponse{
+			Context: req.Context,
+			Error:   &DefaultError,
+		}
+	} else {
+		response = ClientFailureBecknResponse{
+			Context: req.Context,
+			Error:   &errorObj,
+		}
+	}
+	return json.Marshal(response)
+}