From de0470ade133232e1014d9012dd4fcb0b56925a6 Mon Sep 17 00:00:00 2001
From: Sven Nierlein <sven@consol.de>
Date: Mon, 11 Mar 2024 17:23:30 +0100
Subject: [PATCH] add ascii macro post processor

---
 docs/configuration/index.md | 1 +
 pkg/snclient/macro_test.go  | 1 +
 pkg/snclient/macros.go      | 4 ++++
 3 files changed, 6 insertions(+)

diff --git a/docs/configuration/index.md b/docs/configuration/index.md
index 51ff782..cdbda98 100644
--- a/docs/configuration/index.md
+++ b/docs/configuration/index.md
@@ -186,6 +186,7 @@ Support operators are:
 | `:utc`                | 1700834034 -> 2023-11-24 13:53:54 UTC | convert unix timestamp into human readable date (utc timezone) |
 | `:fmt=<fmt>`          | 123.45 -> 123.4                       | apply format, ex.: $(total \| fmt=%.1f) (using GOs fmt.Sprintf) |
 | `:s/regexp/replace/`  | C:\ % -> C                            | apply regexp replacement, ex.: $(name \| 's/\\W//' ) (using GOs regexp.Compile) |
+| `:ascii`              | C:\ % -> C                            | remove any none-ascii characters |
 
 for example, define a dummy command which prints the hostname in lower case letters:
 
diff --git a/pkg/snclient/macro_test.go b/pkg/snclient/macro_test.go
index 81d419a..340152d 100644
--- a/pkg/snclient/macro_test.go
+++ b/pkg/snclient/macro_test.go
@@ -40,6 +40,7 @@ func TestMacros(t *testing.T) {
 		{In: "${characters | 's/^(.*)ß.*?([a-z]+)/$2$1/g' }", Expect: "utföäü"},
 		{In: "${characters | 's/.*(u{1}).*/U/g' }", Expect: "U"},
 		{In: "${characters | 's/\\W//' }", Expect: "utf"},
+		{In: "${characters | ascii }", Expect: "utf"},
 		{In: "$(seconds)$(seconds)", Expect: "130130"},
 		{In: "...'$(seconds)'...", Expect: "...'130'..."},
 	}
diff --git a/pkg/snclient/macros.go b/pkg/snclient/macros.go
index d7475d0..5b38dd1 100644
--- a/pkg/snclient/macros.go
+++ b/pkg/snclient/macros.go
@@ -26,6 +26,8 @@ var (
 	reRuntimeMacro = regexp.MustCompile(`%[` + runtimeMacroChars + `]+%|\$[` + runtimeMacroChars + `]+\$`)
 
 	reFloatFormat = regexp.MustCompile(`^%[.\d]*f$`)
+
+	reAsciiOnly = regexp.MustCompile(`\W`)
 )
 
 /* replaceMacros replaces variables in given string (config ini file style macros).
@@ -182,6 +184,8 @@ func replaceMacroOperators(value string, flags []string) string {
 			value = utils.DurationString(time.Duration(convert.Float64(value) * float64(time.Second)))
 		case "age":
 			value = fmt.Sprintf("%d", time.Now().Unix()-convert.Int64(value))
+		case "ascii":
+			value = reAsciiOnly.ReplaceAllString(value, "")
 		default:
 			value = replaceMacroOpString(value, flag)
 		}