Merge pull request #1066 from Cali0707/sql-v1-fixes

CESQL v1 fixes

Author: duglin

sql/v2/CESQLLexer.g4

@@ -70,7 +70,7 @@ FALSE: 'FALSE';
 
 DQUOTED_STRING_LITERAL:                      DQUOTA_STRING;
 SQUOTED_STRING_LITERAL:                      SQUOTA_STRING;
-INTEGER_LITERAL:                             INT_DIGIT+;
+INTEGER_LITERAL:                             ('+' | '-')? INT_DIGIT+;
 
 // Identifiers
 

sql/v2/errors/errors.go

@@ -0,0 +1,152 @@
+/*
+ Copyright 2024 The CloudEvents Authors
+ SPDX-License-Identifier: Apache-2.0
+*/
+
+package errors
+
+import (
+	"fmt"
+	"strings"
+)
+
+type errorKind int
+
+const (
+	parseError = iota
+	mathError
+	castError
+	missingAttributeError
+	missingFunctionError
+	functionEvaluationError
+	dummyLastError // always add new error classes ABOVE this error
+)
+
+type cesqlError struct {
+	kind    errorKind
+	message string
+}
+
+func (eKind errorKind) String() string {
+	switch eKind {
+	case parseError:
+		return "parse error"
+	case mathError:
+		return "math error"
+	case castError:
+		return "cast error"
+	case missingAttributeError:
+		return "missing attribute error"
+	case missingFunctionError:
+		return "missing function error"
+	case functionEvaluationError:
+		return "function evaluation error"
+	default:
+		return "generic error"
+	}
+
+}
+
+func (cerr cesqlError) Error() string {
+	return fmt.Sprintf("%s: %s", cerr.kind, cerr.message)
+}
+
+func NewParseError(errs []error) error {
+	if len(errs) == 0 {
+		return nil
+	}
+
+	errorMessages := make([]string, 0, len(errs))
+	for _, err := range errs {
+		errorMessages = append(errorMessages, err.Error())
+	}
+
+	return cesqlError{
+		kind:    parseError,
+		message: strings.Join(errorMessages, "|"),
+	}
+}
+
+func IsParseError(err error) bool {
+	if cesqlErr, ok := err.(cesqlError); ok {
+		return cesqlErr.kind == parseError
+	}
+	return false
+}
+
+func IsMathError(err error) bool {
+	if cesqlErr, ok := err.(cesqlError); ok {
+		return cesqlErr.kind == mathError
+	}
+	return false
+}
+
+func NewMathError(message string) error {
+	return cesqlError{
+		kind:    mathError,
+		message: message,
+	}
+}
+
+func IsCastError(err error) bool {
+	if cesqlErr, ok := err.(cesqlError); ok {
+		return cesqlErr.kind == castError
+	}
+	return false
+}
+
+func NewCastError(err error) error {
+	return cesqlError{
+		kind:    castError,
+		message: err.Error(),
+	}
+}
+
+func IsMissingAttributeError(err error) bool {
+	if cesqlErr, ok := err.(cesqlError); ok {
+		return cesqlErr.kind == missingAttributeError
+	}
+	return false
+}
+
+func NewMissingAttributeError(attribute string) error {
+	return cesqlError{
+		kind:    missingAttributeError,
+		message: attribute,
+	}
+}
+
+func IsMissingFunctionError(err error) bool {
+	if cesqlErr, ok := err.(cesqlError); ok {
+		return cesqlErr.kind == missingFunctionError
+	}
+	return false
+}
+
+func NewMissingFunctionError(function string) error {
+	return cesqlError{
+		kind:    missingFunctionError,
+		message: function,
+	}
+}
+
+func IsFunctionEvaluationError(err error) bool {
+	if cesqlErr, ok := err.(cesqlError); ok {
+		return cesqlErr.kind == functionEvaluationError
+	}
+	return false
+}
+
+func NewFunctionEvaluationError(err error) error {
+	return cesqlError{
+		kind:    functionEvaluationError,
+		message: err.Error(),
+	}
+}
+
+func IsGenericError(err error) bool {
+	if cesqlErr, ok := err.(cesqlError); ok {
+		return cesqlErr.kind < 0 || cesqlErr.kind >= dummyLastError
+	}
+	return false
+}

sql/v2/expression/comparison_expressions.go

@@ -19,17 +19,17 @@ type equalExpression struct {
 func (s equalExpression) Evaluate(event cloudevents.Event) (interface{}, error) {
 	leftVal, err := s.left.Evaluate(event)
 	if err != nil {
-		return nil, err
+		return false, err
 	}
 
 	rightVal, err := s.right.Evaluate(event)
 	if err != nil {
-		return nil, err
+		return false, err
 	}
 
 	leftVal, err = utils.Cast(leftVal, cesql.TypeFromVal(rightVal))
 	if err != nil {
-		return nil, err
+		return false, err
 	}
 
 	return (leftVal == rightVal) == s.equal, nil

sql/v2/expression/function_invocation_expression.go

@@ -9,6 +9,7 @@ import (
 	"fmt"
 
 	cesql "github.com/cloudevents/sdk-go/sql/v2"
+	sqlerrors "github.com/cloudevents/sdk-go/sql/v2/errors"
 	"github.com/cloudevents/sdk-go/sql/v2/runtime"
 	"github.com/cloudevents/sdk-go/sql/v2/utils"
 	cloudevents "github.com/cloudevents/sdk-go/v2"
@@ -22,31 +23,44 @@ type functionInvocationExpression struct {
 func (expr functionInvocationExpression) Evaluate(event cloudevents.Event) (interface{}, error) {
 	fn := runtime.ResolveFunction(expr.name, len(expr.argumentsExpression))
 	if fn == nil {
-		return nil, fmt.Errorf("cannot resolve function %s", expr.name)
+		return false, sqlerrors.NewMissingFunctionError(expr.name)
 	}
 
 	args := make([]interface{}, len(expr.argumentsExpression))
 
+	defaultVal := fn.ReturnType().ZeroValue()
+
 	for i, expr := range expr.argumentsExpression {
 		arg, err := expr.Evaluate(event)
 		if err != nil {
-			return nil, err
+			return defaultVal, err
 		}
 
 		argType := fn.ArgType(i)
 		if argType == nil {
-			return nil, fmt.Errorf("cannot resolve arg type at index %d", i)
+			return defaultVal, sqlerrors.NewFunctionEvaluationError(fmt.Errorf("cannot resolve arg type at index %d for function %s", i, fn.Name()))
 		}
 
 		arg, err = utils.Cast(arg, *argType)
 		if err != nil {
-			return nil, err
+			return defaultVal, err
 		}
 
 		args[i] = arg
 	}
 
-	return fn.Run(event, args)
+	result, err := fn.Run(event, args)
+	if result == nil {
+		if err != nil {
+			err = sqlerrors.NewFunctionEvaluationError(fmt.Errorf("function %s encountered error %w and did not return any value, defaulting to the default value for the function", fn.Name(), err))
+		} else {
+			err = sqlerrors.NewFunctionEvaluationError(fmt.Errorf("function %s did not return any value, defaulting to the default value for the function", fn.Name()))
+		}
+
+		return defaultVal, err
+	}
+
+	return result, err
 }
 
 func NewFunctionInvocationExpression(name string, argumentsExpression []cesql.Expression) cesql.Expression {

sql/v2/expression/identifier_expression.go

@@ -6,9 +6,8 @@
 package expression
 
 import (
-	"fmt"
-
 	cesql "github.com/cloudevents/sdk-go/sql/v2"
+	sqlerrors "github.com/cloudevents/sdk-go/sql/v2/errors"
 	"github.com/cloudevents/sdk-go/sql/v2/utils"
 	cloudevents "github.com/cloudevents/sdk-go/v2"
 )
@@ -20,7 +19,7 @@ type identifierExpression struct {
 func (l identifierExpression) Evaluate(event cloudevents.Event) (interface{}, error) {
 	value := utils.GetAttribute(event, l.identifier)
 	if value == nil {
-		return nil, fmt.Errorf("missing attribute '%s'", l.identifier)
+		return false, sqlerrors.NewMissingAttributeError(l.identifier)
 	}
 
 	return value, nil

sql/v2/expression/in_expression.go

@@ -19,18 +19,18 @@ type inExpression struct {
 func (l inExpression) Evaluate(event cloudevents.Event) (interface{}, error) {
 	leftValue, err := l.leftExpression.Evaluate(event)
 	if err != nil {
-		return nil, err
+		return false, err
 	}
 
 	for _, rightExpression := range l.setExpression {
 		rightValue, err := rightExpression.Evaluate(event)
 		if err != nil {
-			return nil, err
+			return false, err
 		}
 
 		rightValue, err = utils.Cast(rightValue, cesql.TypeFromVal(leftValue))
 		if err != nil {
-			return nil, err
+			return false, err
 		}
 
 		if leftValue == rightValue {

sql/v2/expression/integer_comparison_expressions.go

@@ -19,22 +19,22 @@ type integerComparisonExpression struct {
 func (s integerComparisonExpression) Evaluate(event cloudevents.Event) (interface{}, error) {
 	leftVal, err := s.left.Evaluate(event)
 	if err != nil {
-		return nil, err
+		return false, err
 	}
 
 	rightVal, err := s.right.Evaluate(event)
 	if err != nil {
-		return nil, err
+		return false, err
 	}
 
 	leftVal, err = utils.Cast(leftVal, cesql.IntegerType)
 	if err != nil {
-		return nil, err
+		return false, err
 	}
 
 	rightVal, err = utils.Cast(rightVal, cesql.IntegerType)
 	if err != nil {
-		return nil, err
+		return false, err
 	}
 
 	return s.fn(leftVal.(int32), rightVal.(int32)), nil

sql/v2/expression/like_expression.go

@@ -19,12 +19,12 @@ type likeExpression struct {
 func (l likeExpression) Evaluate(event cloudevents.Event) (interface{}, error) {
 	val, err := l.child.Evaluate(event)
 	if err != nil {
-		return nil, err
+		return false, err
 	}
 
 	val, err = utils.Cast(val, cesql.StringType)
 	if err != nil {
-		return nil, err
+		return false, err
 	}
 
 	return matchString(val.(string), l.pattern), nil

sql/v2/expression/logic_expressions.go

@@ -20,12 +20,12 @@ type logicExpression struct {
 func (s logicExpression) Evaluate(event cloudevents.Event) (interface{}, error) {
 	leftVal, err := s.left.Evaluate(event)
 	if err != nil {
-		return nil, err
+		return false, err
 	}
 
 	leftVal, err = utils.Cast(leftVal, cesql.BooleanType)
 	if err != nil {
-		return nil, err
+		return false, err
 	}
 
 	// Don't bother to check the other expression unless we need to
@@ -38,12 +38,12 @@ func (s logicExpression) Evaluate(event cloudevents.Event) (interface{}, error)
 
 	rightVal, err := s.right.Evaluate(event)
 	if err != nil {
-		return nil, err
+		return false, err
 	}
 
 	rightVal, err = utils.Cast(rightVal, cesql.BooleanType)
 	if err != nil {
-		return nil, err
+		return false, err
 	}
 
 	return s.fn(leftVal.(bool), rightVal.(bool)), nil