(Feat): Initial Commit

internal/util/cache_control.go

@@ -0,0 +1,69 @@
+// nolint:revive
+package util
+
+import (
+	"context"
+	"strings"
+)
+
+type CacheControlDirective uint8
+
+const (
+	CacheControlDirectiveNoCache CacheControlDirective = 1 << iota
+	CacheControlDirectiveNoStore
+)
+
+func (d *CacheControlDirective) HasDirective(dir CacheControlDirective) bool { return *d&dir != 0 }
+func (d *CacheControlDirective) AddDirective(dir CacheControlDirective)      { *d |= dir }
+func (d *CacheControlDirective) ClearDirective(dir CacheControlDirective)    { *d &= ^dir }
+func (d *CacheControlDirective) ToggleDirective(dir CacheControlDirective)   { *d ^= dir }
+
+func (d *CacheControlDirective) String() string {
+	res := make([]string, 0)
+
+	if d.HasDirective(CacheControlDirectiveNoCache) {
+		res = append(res, "no-cache")
+	}
+	if d.HasDirective(CacheControlDirectiveNoStore) {
+		res = append(res, "no-store")
+	}
+
+	return strings.Join(res, "|")
+}
+
+func ParseCacheControlDirective(d string) CacheControlDirective {
+	parts := strings.Split(d, "=")
+	switch strings.ToLower(parts[0]) {
+	case "no-cache":
+		return CacheControlDirectiveNoCache
+	case "no-store":
+		return CacheControlDirectiveNoStore
+	default:
+		return 0
+	}
+}
+
+func ParseCacheControlHeader(val string) CacheControlDirective {
+	res := CacheControlDirective(0)
+
+	directives := strings.Split(val, ",")
+	for _, dir := range directives {
+		res |= ParseCacheControlDirective(dir)
+	}
+
+	return res
+}
+
+func CacheControlDirectiveFromContext(ctx context.Context) CacheControlDirective {
+	d := ctx.Value(CTXKeyCacheControl)
+	if d == nil {
+		return CacheControlDirective(0)
+	}
+
+	directive, ok := d.(CacheControlDirective)
+	if !ok {
+		return CacheControlDirective(0)
+	}
+
+	return directive
+}