scylladb-zpp-2024-javascript-driver · ZuzaOsa · Apr 17, 2025 · Mar 10, 2025
diff --git a/lib/client-options.js b/lib/client-options.js
@@ -96,8 +96,7 @@ const errors = require("./errors.js");
 * @property {Number} [maxPrepared] Determines the maximum amount of different prepared queries before evicting items
 * from the internal cache. Reaching a high threshold hints that the queries are not being reused, like when
 * hard-coding parameter values inside the queries.
- * Default: ``500``.
- * [TODO: Add support for this field]
+ * Default: `512`.
 * @property {Object} [policies]
 * [TODO: Add support for this field]
 * @property {LoadBalancingPolicy} [policies.loadBalancing] The load balancing policy instance to be used to determine
@@ -330,7 +329,7 @@ function defaultOptions() {
        authProvider: null,
        requestTracker: null,
        metrics: new metrics.DefaultMetrics(),
-        maxPrepared: 500,
+        maxPrepared: null, // Default is 512, defined on the Rust side
        refreshSchemaDelay: 1000,
        isMetadataSyncEnabled: true,
        prepareOnAllHosts: true,
@@ -668,6 +667,7 @@ function setRustOptions(options) {
    rustOptions.applicationName = options.applicationName;
    rustOptions.applicationVersion = options.applicationVersion;
    rustOptions.keyspace = options.keyspace;
+    rustOptions.cacheSize = options.maxPrepared;
    if (options.credentials) {
        rustOptions.credentialsUsername = options.credentials.username;
        rustOptions.credentialsPassword = options.credentials.password;

diff --git a/src/session.rs b/src/session.rs
@@ -1,4 +1,4 @@
-use scylla::client::session::Session;
+use scylla::client::caching_session::CachingSession;
 use scylla::client::session_builder::SessionBuilder;
 use scylla::client::SelfIdentity;
 use scylla::response::PagingState;
@@ -16,6 +16,8 @@ use crate::{
    requests::request::PreparedStatementWrapper, result::QueryResultWrapper, utils::err_to_napi,
 };

+const DEFAULT_CACHE_SIZE: u32 = 512;
+
 #[napi]
 pub struct SessionOptions {
    pub connect_points: Vec<String>,
@@ -24,6 +26,7 @@ pub struct SessionOptions {
    pub application_version: Option<String>,
    pub credentials_username: Option<String>,
    pub credentials_password: Option<String>,
+    pub cache_size: Option<u32>,
 }

 #[napi]
@@ -33,7 +36,7 @@ pub struct BatchWrapper {

 #[napi]
 pub struct SessionWrapper {
-    inner: Session,
+    inner: CachingSession,
 }

 #[napi]
@@ -48,6 +51,7 @@ impl SessionOptions {
            application_version: None,
            credentials_username: None,
            credentials_password: None,
+            cache_size: None,
        }
    }
 }
@@ -59,13 +63,21 @@ impl SessionWrapper {
    pub async fn create_session(options: &SessionOptions) -> napi::Result<Self> {
        let builder = configure_session_builder(options);
        let session = builder.build().await.map_err(err_to_napi)?;
+        let session: CachingSession = CachingSession::from(
+            session,
+            options.cache_size.unwrap_or(DEFAULT_CACHE_SIZE) as usize,
+        );
        Ok(SessionWrapper { inner: session })
    }

    /// Returns the name of the current keyspace
    #[napi]
    pub fn get_keyspace(&self) -> Option<String> {
-        self.inner.get_keyspace().as_deref().map(ToOwned::to_owned)
+        self.inner
+            .get_session()
+            .get_keyspace()
+            .as_deref()
+            .map(ToOwned::to_owned)
    }

    /// Executes unprepared statement. This assumes the types will be either guessed or provided by user.
@@ -85,6 +97,7 @@ impl SessionWrapper {
        let params_vec = MaybeUnsetQueryParameterWrapper::extract_parameters(params);
        let query_result = self
            .inner
+            .get_session()
            .query_unpaged(statement, params_vec)
            .await
            .map_err(err_to_napi)?;
@@ -98,8 +111,13 @@ impl SessionWrapper {
        &self,
        statement: String,
    ) -> napi::Result<PreparedStatementWrapper> {
+        let statement: Statement = statement.into();
        Ok(PreparedStatementWrapper {
-            prepared: self.inner.prepare(statement).await.map_err(err_to_napi)?,
+            prepared: self
+                .inner
+                .add_prepared_statement(&statement) // TODO: change for add_prepared_statement_to_owned after it is made public
+                .await
+                .map_err(err_to_napi)?,
        })
    }

@@ -123,6 +141,7 @@ impl SessionWrapper {
        let query = apply_prepared_options(query.prepared.clone(), options)?;
        QueryResultWrapper::from_query(
            self.inner
+                .get_session()
                .execute_unpaged(&query, params_vec)
                .await
                .map_err(err_to_napi)?,
@@ -174,6 +193,7 @@ impl SessionWrapper {

        let (result, paging_state_response) = self
            .inner
+            .get_session()
            .query_single_page(statement, values, paging_state)
            .await
            .map_err(err_to_napi)?;
@@ -208,6 +228,7 @@ impl SessionWrapper {

        let (result, paging_state) = self
            .inner
+            .get_session()
            .execute_single_page(&prepared, values, paging_state)
            .await
            .map_err(err_to_napi)?;