实现缓存策略的部分功能

internal/caches/writer_gzip.go

@@ -0,0 +1,47 @@
+package caches
+
+import "compress/gzip"
+
+type gzipWriter struct {
+	rawWriter Writer
+	writer    *gzip.Writer
+	key       string
+	expiredAt int64
+}
+
+func NewGzipWriter(gw Writer, key string, expiredAt int64) Writer {
+	return &gzipWriter{
+		rawWriter: gw,
+		writer:    gzip.NewWriter(gw),
+		key:       key,
+		expiredAt: expiredAt,
+	}
+}
+
+func (this *gzipWriter) Write(data []byte) (n int, err error) {
+	return this.writer.Write(data)
+}
+
+func (this *gzipWriter) Close() error {
+	err := this.writer.Close()
+	if err != nil {
+		return err
+	}
+	return this.rawWriter.Close()
+}
+
+func (this *gzipWriter) Discard() error {
+	err := this.writer.Close()
+	if err != nil {
+		return err
+	}
+	return this.rawWriter.Discard()
+}
+
+func (this *gzipWriter) Key() string {
+	return this.key
+}
+
+func (this *gzipWriter) ExpiredAt() int64 {
+	return this.expiredAt
+}