Fix up parser

processor/jsonpath/jsonpath.go

@@ -1,4 +1,4 @@
-package main
+package jsonpath
 
 import (
 	"fmt"
@@ -27,12 +27,14 @@ func ParseJSONPath(path string) ([]JSONStep, error) {
 		return nil, fmt.Errorf("path must start with $")
 	}
 
-	path = path[1:]
 	steps := []JSONStep{}
 	i := 0
 
 	for i < len(path) {
 		switch path[i] {
+		case '$':
+			steps = append(steps, JSONStep{Type: RootStep})
+			i++
 		case '.':
 			i++
 			if i < len(path) && path[i] == '.' {
@@ -51,7 +53,6 @@ func ParseJSONPath(path string) ([]JSONStep, error) {
 				}
 				i = nextPos
 			}
-
 		case '[':
 			// Index step
 			i++
@@ -66,7 +67,6 @@ func ParseJSONPath(path string) ([]JSONStep, error) {
 				steps = append(steps, JSONStep{Type: IndexStep, Index: index})
 			}
 			i = nextPos + 1 // Skip closing ]
-
 		default:
 			return nil, fmt.Errorf("unexpected character: %c", path[i])
 		}