scylladb/scylla-rust-driver

Problem Statement #1866 introduced BoundStatement, but provided no way to change its configuration after binding. This means that all settings must be done on PreparedStatement before binding. In some cases this might be inconvenient (e.g. because the settings can only be known right before execution, which happens elsewhere than the binding). Naive Solution Expose prepared_mut(&mut self) method on BoundStatement. While this would allow changing all the settings as desired, this would also create a hole in our type-level guarantees: a BoundStatement could be fed with a wrong PreparedStatement by calling std::mem::swap() on prepared_mut(). Thus this is invalid. Suggested Solution Introduce setters to BoundStatement, essentially duplicating what PreparedStatement exposes. While verbose and boilerplatey, it's the best we can offer.

📌 I think we should group our examples into directories by topic. This will also make it more discoverable what examples we're still missing. Example topics: performance (parallel) marshalling/deser (custom deser, UDT) observability (tracing, logging, metrics, query_history) security (TLS, auth) configuration (exec profiles) load balancing (enforce coordinator, custom LBP, speculative execution?) I don't yet know how to categorise batches, select paging, get by name, tower, schema agreement, cqlsh-rs, basic, client_routes, compare_tokens. Originally posted by @wprzytula in #1813 (comment)

What I spotted 🤔 Are these examples asymmetrical? custom_deserialization teaches DeserializeValue, custom_serialization teaches SerializeRow. What about SerializeValue and DeserializeRow? How is user_defined_type example related to this? Originally posted by @wprzytula in #1813 (comment) Suggested solution Inspect examples: custom_serialization, custom_deserialization, user_defined_type. See what's missing and add it. Think about better structuring of those examples.

The num-bigint varint deserializer passes an empty payload directly to the integer constructor. Code permalink: scylla-rust-driver/scylla-cql/src/deserialize/value.rs Line 247 in e04a12a let val = ensure_not_null_slice::<Self>(typ, v)?; The constructor interprets an empty byte slice as numeric zero. Empty varint payloads are a distinct CQL empty value, while canonical zero is encoded differently, so direct deserialization can silently turn empty into zero instead of requiring an empty-aware wrapper to preserve it. Suggested direction: reject empty payloads for direct bigint deserialization, or otherwise route them through the existing empty-value handling path.

The proxy chooses the shard-aware outgoing socket family from the proxy listener address instead of the real node address. Code permalink: scylla-rust-driver/scylla-proxy/src/proxy.rs Line 897 in e04a12a let socket = match self.node.proxy_addr().ip() { With mixed IPv4/IPv6 proxy and node addresses, the cluster-side connect can fail with an address-family error. IPv6 shard-aware setups can also fail before connecting because the later bind path uses an IPv4 wildcard. Suggested direction: select the socket and bind address family from the real node address used for the cluster-side connection.