From 2dad184dcfe2f74c971860822004399c1ec92fbc Mon Sep 17 00:00:00 2001
From: Ian Fijolek <ian@iamthefij.com>
Date: Fri, 28 Jan 2022 09:53:21 -0800
Subject: [PATCH] More graceful handling of bad match functions

---
 config.go | 12 +++++++++---
 1 file changed, 9 insertions(+), 3 deletions(-)

diff --git a/config.go b/config.go
index 63305d8..c40173d 100644
--- a/config.go
+++ b/config.go
@@ -51,12 +51,18 @@ func MakeMatchFunc(rule string) MatchFunc {
 			"hostname": dest.Hostname(),
 			"url":      dest,
 		}
-		matchFunc, err := expr.Eval(rule, env)
+		matchFuncExpr, err := expr.Eval(rule, env)
 		if err != nil {
-			panic(err)
+			fmt.Printf("Error evaluating rule %s: %v", rule, err)
+			return false
 		}
 
-		return matchFunc.(MatchFunc)(dest)
+		matchFunc, ok := matchFuncExpr.(MatchFunc)
+		if !ok {
+			fmt.Printf("Error evaluating rule %s. Did not evaluate to a MatchFunc.", rule)
+			return false
+		}
+		return matchFunc(dest)
 	}
 }