Here we go again...

pkg/types/header.go

@@ -0,0 +1,52 @@
+package types
+
+import "strings"
+
+type Header KeyValue[string, []string]
+
+type Headers []Header
+
+// Has checks if a header with the given key exists.
+func (headers Headers) Has(key string) bool {
+	for i := range headers {
+		if headers[i].Key == key {
+			return true
+		}
+	}
+	return false
+}
+
+func (headers Headers) GetValue(key string) *[]string {
+	for i := range headers {
+		if headers[i].Key == key {
+			return &headers[i].Value
+		}
+	}
+	return nil
+}
+
+func (headers *Headers) Append(header Header) {
+	if item := headers.GetValue(header.Key); item != nil {
+		*item = append(*item, header.Value...)
+	} else {
+		*headers = append(*headers, header)
+	}
+}
+
+func (headers *Headers) Parse(rawValues ...string) {
+	for _, rawValue := range rawValues {
+		headers.Append(*ParseHeader(rawValue))
+	}
+}
+
+func ParseHeader(rawValue string) *Header {
+	parts := strings.SplitN(rawValue, ": ", 2)
+	switch len(parts) {
+	case 1:
+		return &Header{Key: parts[0], Value: []string{""}}
+	case 2:
+		return &Header{Key: parts[0], Value: []string{parts[1]}}
+	default:
+		return &Header{Key: "", Value: []string{""}}
+	}
+}