serialize/value: serialize Bytes as CQL blob

`Bytes` deserialization from CQL `blob` has already been implemented,
so for completeness, we implement serialization of `Bytes` to CQL
`blob`. This has been requested in an issue: #1394.

Author: wprzytula

scylla-cql/src/serialize/value.rs

@@ -10,6 +10,7 @@ use std::net::IpAddr;
 use std::ops::Deref as _;
 use std::sync::Arc;
 
+use bytes::Bytes;
 use thiserror::Error;
 use uuid::Uuid;
 
@@ -326,6 +327,14 @@ impl<const N: usize> SerializeValue for [u8; N] {
             .map_err(|_| mk_ser_err::<Self>(typ, BuiltinSerializationErrorKind::SizeOverflow))?
     });
 }
+impl SerializeValue for Bytes {
+    impl_serialize_via_writer!(|me, typ, writer| {
+        exact_type_check!(typ, Blob);
+        writer
+            .set_value(me)
+            .map_err(|_| mk_ser_err::<Self>(typ, BuiltinSerializationErrorKind::SizeOverflow))?
+    });
+}
 impl SerializeValue for IpAddr {
     impl_serialize_via_writer!(|me, typ, writer| {
         exact_type_check!(typ, Inet);

scylla-cql/src/serialize/value_tests.rs

@@ -21,6 +21,7 @@ use std::str::FromStr;
 use std::sync::Arc;
 
 use assert_matches::assert_matches;
+use bytes::Bytes;
 use thiserror::Error;
 use uuid::Uuid;
 
@@ -1832,6 +1833,15 @@ fn u8_slice_serialization() {
     );
 }
 
+#[test]
+fn bytes_serialization() {
+    let val = Bytes::from_static(&[1u8, 1, 1, 1]);
+    assert_eq!(
+        do_serialize(val, &ColumnType::Native(NativeType::Blob)),
+        vec![0, 0, 0, 4, 1, 1, 1, 1]
+    );
+}
+
 #[test]
 fn cql_date_serialization() {
     assert_eq!(