feat: cache init

Signed-off-by: monkey92t <golang@88.com>

cache.go

@@ -0,0 +1,107 @@
+package redis
+
+import (
+	"context"
+	"time"
+
+	"github.com/redis/go-redis/v9/internal/pool"
+	"github.com/redis/go-redis/v9/internal/proto"
+)
+
+type Cache interface{}
+
+type cache struct {
+	// cluster? sentinel?
+	conn *Conn
+}
+
+func newCache() Cache {
+	// ?
+	return &cache{}
+}
+
+// ------------------------------------------------------------------------------------------
+
+// extension method
+
+func (c *Conn) readReply(ctx context.Context, timeout time.Duration, fn func(rd *proto.Reader) error) error {
+	return c.withConn(ctx, func(ctx context.Context, conn *pool.Conn) error {
+		return conn.WithReader(ctx, timeout, fn)
+	})
+}
+
+// ------------------------------------------------------------------------------------------
+
+// Client-side caching command.
+
+type trackingArgs struct {
+	redirect  int
+	prefixes  []string
+	broadcast bool
+	optIn     bool
+	optOut    bool
+	noLoop    bool
+}
+
+func (c *cache) clientTracking(ctx context.Context, t *trackingArgs) *StringCmd {
+	args := make([]any, 0, 7+len(t.prefixes))
+	args = append(args, "CLIENT", "TRACKING", "ON")
+	if t.redirect > 0 {
+		args = append(args, "REDIRECT", t.redirect)
+	}
+	if len(t.prefixes) > 0 {
+		for _, prefix := range t.prefixes {
+			args = append(args, "PREFIX", prefix)
+		}
+	}
+	if t.optIn {
+		args = append(args, "OPTIN")
+	}
+	if t.optOut {
+		args = append(args, "OPTOUT")
+	}
+	if t.noLoop {
+		args = append(args, "NOLOOP")
+	}
+	cmd := NewStringCmd(ctx, args...)
+	_ = c.conn.Process(ctx, cmd)
+	return cmd
+}
+
+func (c *cache) trackingClose(ctx context.Context) error {
+	return c.conn.Process(ctx, NewStringCmd(ctx, "CLIENT", "TRACKING", "OFF"))
+}
+
+func (c *cache) cachingYes(ctx context.Context) error {
+	return c.conn.Process(ctx, NewStringCmd(ctx, "CLIENT", "CACHING", "YES"))
+}
+
+func (c *cache) cachingNo(ctx context.Context) error {
+	return c.conn.Process(ctx, NewStringCmd(ctx, "CLIENT", "CACHING", "NO"))
+}
+
+// ------------------------------------------------------------------------------------
+
+// invalidatePush check if the data packet is a key-invalidate push and return the invalid key.
+func (c *cache) invalidatePush(v []any) ([]string, bool) {
+	if len(v) != 2 {
+		return nil, false
+	}
+	if s, ok := v[0].(string); !ok || s != "invalidate" {
+		return nil, false
+	}
+	slice, ok := v[1].([]any)
+	if !ok {
+		return nil, false
+	}
+
+	keys := make([]string, 0, len(slice))
+	for i := 0; i < len(slice); i++ {
+		if s, ok := slice[i].(string); ok {
+			keys = append(keys, s)
+		}
+	}
+	return keys, true
+}
+
+// ------------------------------------- Broadcasting -------------------------------------