feat(distlock): implement distributed Locker based on Redlock algorithm

pkg/distlock/node.go

@@ -0,0 +1,29 @@
+package distlock
+
+import (
+	"context"
+	"time"
+)
+
+// Cluster provides point-in-time snapshots of the independent nodes that participate in distributed leases.
+// Implementations must be safe for concurrent use.
+type Cluster interface {
+	// Nodes returns each node counted toward quorum exactly once, including nodes that are temporarily unavailable.
+	// The Locker may keep and use the returned nodes throughout acquisition and until any acquired lease is released.
+	Nodes(ctx context.Context) ([]Node, error)
+}
+
+// Node provides lease operations on a single cluster node.
+//
+// Each operation performs one attempt. A true result means the operation took effect. A false result with no error
+// means the node responded but its lease state rejected the operation. If err is non-nil, the result is unknown and
+// the boolean result must be ignored. Implementations must return promptly when ctx is cancelled, not modify token,
+// and be safe for concurrent use.
+type Node interface {
+	// Acquire creates a lease when resource does not have an unexpired lease.
+	Acquire(ctx context.Context, resource string, token []byte, ttl time.Duration) (bool, error)
+	// Renew extends an unexpired lease when its ownership token matches.
+	Renew(ctx context.Context, resource string, token []byte, ttl time.Duration) (bool, error)
+	// Release removes an unexpired lease when its ownership token matches.
+	Release(ctx context.Context, resource string, token []byte) (bool, error)
+}