marvinlanhenke commented on code in PR #324: URL: https://github.com/apache/iceberg-rust/pull/324#discussion_r1584803007
########## crates/integrations/datafusion/src/schema.rs: ########## @@ -0,0 +1,99 @@ +// Licensed to the Apache Software Foundation (ASF) under one +// or more contributor license agreements. See the NOTICE file +// distributed with this work for additional information +// regarding copyright ownership. The ASF licenses this file +// to you under the Apache License, Version 2.0 (the +// "License"); you may not use this file except in compliance +// with the License. You may obtain a copy of the License at +// +// http://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, +// software distributed under the License is distributed on an +// "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY +// KIND, either express or implied. See the License for the +// specific language governing permissions and limitations +// under the License. + +use std::{any::Any, collections::HashMap, sync::Arc}; + +use async_trait::async_trait; +use datafusion::{catalog::schema::SchemaProvider, datasource::TableProvider}; +use futures::future::try_join_all; +use iceberg::{Catalog, NamespaceIdent, Result}; + +use crate::table::IcebergTableProvider; + +/// Represents a [`SchemaProvider`] for the Iceberg [`Catalog`], managing +/// access to table providers within a specific namespace. +pub(crate) struct IcebergSchemaProvider { + /// A `HashMap` where keys are table names + /// and values are dynamic references to objects implementing the + /// [`TableProvider`] trait. + tables: HashMap<String, Arc<dyn TableProvider>>, +} + +impl IcebergSchemaProvider { + /// Asynchronously tries to construct a new [`IcebergSchemaProvider`] + /// using the given client to fetch and initialize table providers for + /// the provided namespace in the Iceberg [`Catalog`]. + /// + /// This method retrieves a list of table names + /// attempts to create a table provider for each table name, and + /// collects these providers into a `HashMap`. + pub(crate) async fn try_new( + client: Arc<dyn Catalog>, + namespace: NamespaceIdent, + ) -> Result<Self> { + // TODO: + // Tables and providers should be cached based on table_name + // if we have a cache miss; we update our internal cache & check again + // As of right now; tables might become stale. + let table_names: Vec<_> = client + .list_tables(&namespace) + .await? + .iter() + .map(|tbl| tbl.name().to_string()) + .collect(); + + let providers = try_join_all( + table_names + .iter() + .map(|name| IcebergTableProvider::try_new(client.clone(), namespace.clone(), name)) + .collect::<Vec<_>>(), + ) + .await?; + + let tables: Vec<_> = table_names + .into_iter() + .zip(providers.into_iter()) + .map(|(name, provider)| { + let provider = Arc::new(provider) as Arc<dyn TableProvider>; + (name, provider) + }) + .collect(); + + Ok(IcebergSchemaProvider { + tables: tables.into_iter().collect(), + }) + } +} + +#[async_trait] +impl SchemaProvider for IcebergSchemaProvider { + fn as_any(&self) -> &dyn Any { + self + } + + fn table_names(&self) -> Vec<String> { + self.tables.keys().cloned().collect() + } + + fn table_exist(&self, name: &str) -> bool { + self.tables.get(name).is_some() + } + + async fn table(&self, name: &str) -> datafusion::error::Result<Option<Arc<dyn TableProvider>>> { Review Comment: yes - i like that. fixed. -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. To unsubscribe, e-mail: issues-unsubscr...@iceberg.apache.org For queries about this service, please contact Infrastructure at: us...@infra.apache.org --------------------------------------------------------------------- To unsubscribe, e-mail: issues-unsubscr...@iceberg.apache.org For additional commands, e-mail: issues-h...@iceberg.apache.org
