liurenjie1024 commented on code in PR #324: URL: https://github.com/apache/iceberg-rust/pull/324#discussion_r1584505866
########## crates/integrations/datafusion/src/catalog.rs: ########## @@ -0,0 +1,94 @@ +// 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 datafusion::catalog::{schema::SchemaProvider, CatalogProvider}; +use futures::future::try_join_all; +use iceberg::{Catalog, NamespaceIdent, Result}; + +use crate::schema::IcebergSchemaProvider; + +/// Provides an interface to manage and access multiple schemas +/// within an Iceberg [`Catalog`]. +/// +/// Acts as a centralized catalog provider that aggregates +/// multiple [`SchemaProvider`], each associated with distinct namespaces. +pub struct IcebergCatalogProvider { + /// A concurrent `HashMap` where keys are namespace names + /// and values are dynamic references to objects implementing the + /// [`SchemaProvider`] trait. + schemas: HashMap<String, Arc<dyn SchemaProvider>>, +} + +impl IcebergCatalogProvider { + /// Asynchronously tries to construct a new [`IcebergCatalogProvider`] + /// using the given client to fetch and initialize schema providers for + /// each namespace in the Iceberg [`Catalog`]. + /// + /// This method retrieves the list of namespace names + /// attempts to create a schema provider for each namespace, and + /// collects these providers into a concurrent `HashMap`. + pub async fn try_new(client: Arc<dyn Catalog>) -> Result<Self> { + let schema_names: Vec<_> = client + .list_namespaces(None) + .await? + .iter() + .flat_map(|ns| ns.as_ref().clone()) + .collect(); + + let providers = try_join_all( + schema_names + .iter() + .map(|name| { + IcebergSchemaProvider::try_new( + client.clone(), + NamespaceIdent::new(name.clone()), + ) + }) + .collect::<Vec<_>>(), + ) + .await?; + + let schemas: Vec<_> = schema_names + .into_iter() + .zip(providers.into_iter()) + .map(|(name, provider)| { + let provider = Arc::new(provider) as Arc<dyn SchemaProvider>; + (name, provider) + }) + .collect(); + + Ok(IcebergCatalogProvider { + schemas: schemas.into_iter().collect(), + }) + } +} + +impl CatalogProvider for IcebergCatalogProvider { + fn as_any(&self) -> &dyn Any { + self + } + + fn schema_names(&self) -> Vec<String> { + self.schemas.keys().cloned().collect() Review Comment: > This makes sense, but I see the issue with blocking on async calls. At first, I would take the price of waiting for the blocking calls. Even it is still a remote call, the ones to the REST catalog should be lightning-fast (that's where the caching happens). I think blocking + timeout would be a reasonable solution before we implement sophiscated caching. For this pr, we can leave it as now since it's even not caching, it's a snapshot. WDYT? -- 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
