#12 Add tokenizer outline

.mockery.yaml

@@ -9,4 +9,5 @@ packages:
   waffle/internal/rule:
     interfaces:
       Builder:
-      node:
+      Tokenizer:
+      node:

internal/rule/compiler.go

@@ -35,7 +35,7 @@ func (c *CustomCompiler) Compile(name, value string) (*Predicate, error) {
 		return nil, fmt.Errorf("validate name and value: %w", err)
 	}
 
-	variable, expression, err := getVariableAndLogicalExpression(strings.TrimSpace(value))
+	variable, expression, err := getVariableAndLogicalExpression(value)
 	if err != nil {
 		return nil, fmt.Errorf("get variable and logical expression for predicate: %w", err)
 	}

internal/rule/predicate.go

@@ -4,41 +4,6 @@ import (
 	"waffle/internal/request"
 )
 
-const (
-	operatorEq    = "=="
-	operatorNotEq = "!="
-	operatorGt    = ">"
-	operatorLs    = "<"
-
-	methodLength = "LEN"
-	methodFormat = "FORMAT"
-
-	fieldPayload = "payload"
-	fieldHeaders = "headers"
-)
-
-var (
-	// operators are compilable operators.
-	operators = []string{
-		operatorEq,
-		operatorNotEq,
-		operatorGt,
-		operatorLs,
-	}
-
-	// methods are compilable methods.
-	methods = []string{
-		methodLength,
-		methodFormat,
-	}
-
-	// fields are compilable fields available in the request wrapper.
-	fields = []string{
-		fieldPayload,
-		fieldHeaders,
-	}
-)
-
 type Predicate struct {
 	Name string
 	Eval func(r *request.Wrapper) bool

internal/rule/tokenizer.go

@@ -0,0 +1,56 @@
+package rule
+
+const (
+	operatorEq    = "=="
+	operatorNotEq = "!="
+	operatorGt    = ">"
+	operatorLs    = "<"
+
+	methodLength = "LEN"
+	methodFormat = "FORMAT"
+
+	fieldPayload = "payload"
+	fieldHeaders = "headers"
+)
+
+var (
+	// operators are compilable operators.
+	operators = []string{
+		operatorEq,
+		operatorNotEq,
+		operatorGt,
+		operatorLs,
+	}
+
+	// methods are compilable methods.
+	methods = []string{
+		methodLength,
+		methodFormat,
+	}
+
+	// fields are compilable fields available in the request wrapper.
+	fields = []string{
+		fieldPayload,
+		fieldHeaders,
+	}
+)
+
+type expressionTree node
+
+type Tokenizer interface {
+	BuildExpressionTree(variable, expression string) (expressionTree, error)
+}
+
+type customRulesTokenizer struct {
+}
+
+var _ Tokenizer = (*customRulesTokenizer)(nil)
+
+func newCustomRulesTokenizer() *customRulesTokenizer {
+	return &customRulesTokenizer{}
+}
+
+func (c *customRulesTokenizer) BuildExpressionTree(variable, expression string) (expressionTree, error) {
+	//TODO implement me
+	panic("implement me")
+}