From abbc9d6b19c5f5bdaaa3b7c15b2bd2d768325549 Mon Sep 17 00:00:00 2001
From: Matthew Turner <matthew.m.turner@outlook.com>
Date: Sat, 5 Apr 2025 11:15:47 -0400
Subject: [PATCH] Start setting up indexmap cache

---
 crates/datafusion-app/Cargo.toml              |  1 +
 .../src/cache/indexmap_cache.rs               | 78 +++++++++++++++++++
 crates/datafusion-app/src/cache/mod.rs        | 18 +++++
 crates/datafusion-app/src/lib.rs              |  1 +
 4 files changed, 98 insertions(+)
 create mode 100644 crates/datafusion-app/src/cache/indexmap_cache.rs
 create mode 100644 crates/datafusion-app/src/cache/mod.rs

diff --git a/crates/datafusion-app/Cargo.toml b/crates/datafusion-app/Cargo.toml
index ad83185..2c2076d 100644
--- a/crates/datafusion-app/Cargo.toml
+++ b/crates/datafusion-app/Cargo.toml
@@ -57,6 +57,7 @@ iceberg = ["dep:iceberg-catalog-rest", "dep:iceberg-datafusion"]
 observability = []
 s3 = ["object_store/aws", "url"]
 udfs-wasm = ["dep:datafusion-udfs-wasm"]
+object_store = ["dep:object_store"]
 
 [lints.clippy]
 clone_on_ref_ptr = "deny"
diff --git a/crates/datafusion-app/src/cache/indexmap_cache.rs b/crates/datafusion-app/src/cache/indexmap_cache.rs
new file mode 100644
index 0000000..9f771bd
--- /dev/null
+++ b/crates/datafusion-app/src/cache/indexmap_cache.rs
@@ -0,0 +1,78 @@
+// 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::sync::Arc;
+
+use datafusion::execution::cache::CacheAccessor;
+use indexmap::IndexMap;
+use object_store::{path::Path, ObjectMeta};
+
+struct IndexMapFileCache {
+    name: String,
+    inner: IndexMap<Path, Arc<Vec<ObjectMeta>>>,
+}
+
+impl IndexMapFileCache {
+    pub fn new(name: String, data: IndexMap<Path, Arc<Vec<ObjectMeta>>>) -> Self {
+        Self { name, inner: data }
+    }
+}
+
+impl CacheAccessor<Path, Arc<Vec<ObjectMeta>>> for IndexMapFileCache {
+    type Extra = ObjectMeta;
+
+    fn name(&self) -> String {
+        self.name.clone()
+    }
+
+    fn get(&self, k: &Path) -> Option<Arc<Vec<ObjectMeta>>> {
+        todo!()
+    }
+
+    fn get_with_extra(&self, k: &Path, e: &Self::Extra) -> Option<Arc<Vec<ObjectMeta>>> {
+        todo!()
+    }
+
+    fn put(&self, key: &Path, value: Arc<Vec<ObjectMeta>>) -> Option<Arc<Vec<ObjectMeta>>> {
+        todo!()
+    }
+
+    fn put_with_extra(
+        &self,
+        key: &Path,
+        value: Arc<Vec<ObjectMeta>>,
+        e: &Self::Extra,
+    ) -> Option<Arc<Vec<ObjectMeta>>> {
+        todo!()
+    }
+
+    fn remove(&mut self, k: &Path) -> Option<Arc<Vec<ObjectMeta>>> {
+        todo!()
+    }
+
+    fn contains_key(&self, k: &Path) -> bool {
+        todo!()
+    }
+
+    fn len(&self) -> usize {
+        todo!()
+    }
+
+    fn clear(&self) {
+        todo!()
+    }
+}
diff --git a/crates/datafusion-app/src/cache/mod.rs b/crates/datafusion-app/src/cache/mod.rs
new file mode 100644
index 0000000..8222612
--- /dev/null
+++ b/crates/datafusion-app/src/cache/mod.rs
@@ -0,0 +1,18 @@
+// 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.
+
+pub mod indexmap_cache;
diff --git a/crates/datafusion-app/src/lib.rs b/crates/datafusion-app/src/lib.rs
index ba5635b..d2e89af 100644
--- a/crates/datafusion-app/src/lib.rs
+++ b/crates/datafusion-app/src/lib.rs
@@ -15,6 +15,7 @@
 // specific language governing permissions and limitations
 // under the License.
 
+pub mod cache;
 pub mod catalog;
 pub mod config;
 pub mod executor;