Improved warning around GenerateRandomKey.

1 files changed, 3 insertions, 0 deletions

diff --git a/securecookie.go b/securecookie.go
index 7dd373d..b1cb144 100644
--- a/securecookie.go
+++ b/securecookie.go
@@ -474,6 +474,9 @@ func decode(value []byte) ([]byte, error) {
 
 // GenerateRandomKey creates a random key with the given length in bytes.
 // On failure, returns nil.
+//
+// Callers should explicitly check for the possibility of a nil return, treat
+// it as a failure of the system random number generator, and not continue.
 func GenerateRandomKey(length int) []byte {
 	k := make([]byte, length)
 	if _, err := io.ReadFull(rand.Reader, k); err != nil {