Enable template function splitToMap

docs/templating-language.md

@@ -75,6 +75,7 @@ provides the following functions:
   - [sha256Hex](#sha256hex)
   - [md5sum](#md5sum)
   - [split](#split)
+  - [splitToMap](#splitToMap)
   - [timestamp](#timestamp)
   - [toJSON](#tojson)
   - [toJSONPretty](#tojsonpretty)
@@ -1499,6 +1500,14 @@ This can be combined with chained and piped with other functions:
 {{ key "foo" | toUpper | split "\n" | join "," }}
 ```
 
+### `splitToMap`
+
+Splits the given string on the provided separator and splits each resulting item into a key and value:
+
+```golang
+{{ "foo:bar\nbaz:bat\n" | splitToMap "\n" ":" }}
+```
+
 ### `timestamp`
 
 Returns the current timestamp as a string (UTC). If no arguments are given, the

template/funcs.go

@@ -1203,6 +1203,26 @@ func split(sep, s string) ([]string, error) {
 	return strings.Split(s, sep), nil
 }
 
+// splitToMap is a version of strings.Split which splits a second time for each
+// item in the slice generated from the first split, building a map
+func splitToMap(sep1, sep2, s string) (map[string]string, error) {
+	s = strings.TrimSpace(s)
+	if s == "" {
+		emptyMap := make(map[string]string)
+		return emptyMap, nil
+	}
+	s1 := strings.Split(s, sep1)
+	m:=make(map[string]string, len(s1))
+	for i := range s1 {
+		k,v,f:=strings.Cut(s1[i],sep2)
+		if !f {
+			continue
+		}
+		m[k]=v
+	}
+	return m, nil
+}
+
 // timestamp returns the current UNIX timestamp in UTC. If an argument is
 // specified, it will be used to format the timestamp.
 func timestamp(s ...string) (string, error) {

template/template.go

@@ -379,6 +379,7 @@ func funcMap(i *funcMapInput) template.FuncMap {
 		"toUpper":               toUpper,
 		"toYAML":                toYAML,
 		"split":                 split,
+		"splitToMap":            splitToMap,
 		"byMeta":                byMeta,
 		"sockaddr":              sockaddr,
 		"writeToFile":           writeToFile,

template/template_test.go

@@ -1685,6 +1685,17 @@ func TestTemplate_Execute(t *testing.T) {
 			"[a b c]",
 			false,
 		},
+		{
+			"helper_splitToMap",
+			&NewTemplateInput{
+				Contents: `{{ "a:x,b:y,c:z" | splitToMap "," ":" }}`,
+			},
+			&ExecuteInput{
+				Brain: NewBrain(),
+			},
+			"map[a:x b:y c:z]",
+			false,
+		},
 		{
 			"helper_timestamp",
 			&NewTemplateInput{