PLT-5308 Caching layer part 2 (#6973)

* Adding Reaction store cache layer example

* Implementing reaction store in new caching system.

* Redis for reaction store

* Adding redis library

* Adding invalidation for DeleteAllWithEmojiName and other minor enhancements

1 files changed, 23 insertions, 0 deletions

diff --git a/vendor/github.com/go-redis/redis/internal/internal.go b/vendor/github.com/go-redis/redis/internal/internal.go
new file mode 100644
index 000000000..fb4efa5f0
--- /dev/null
+++ b/vendor/github.com/go-redis/redis/internal/internal.go
@@ -0,0 +1,23 @@
+package internal
+
+import (
+	"math/rand"
+	"time"
+)
+
+const retryBackoff = 8 * time.Millisecond
+
+// Retry backoff with jitter sleep to prevent overloaded conditions during intervals
+// https://www.awsarchitectureblog.com/2015/03/backoff.html
+func RetryBackoff(retry int, maxRetryBackoff time.Duration) time.Duration {
+	if retry < 0 {
+		retry = 0
+	}
+
+	backoff := retryBackoff << uint(retry)
+	if backoff > maxRetryBackoff {
+		backoff = maxRetryBackoff
+	}
+
+	return time.Duration(rand.Int63n(int64(backoff)))
+}