From e3a58bec6293a1c6a21794bf08022719b969a56f Mon Sep 17 00:00:00 2001
From: fanng <xiaojing@datastrato.com>
Date: Sun, 1 Sep 2024 19:32:44 +0800
Subject: [PATCH] support projection pushdown for datafusion iceberg

---
 crates/examples/src/datafusion_read_data.rs | 37 +++++++++++++++++++++
 crates/examples/src/utils.rs                | 31 +++++++++++++++++
 2 files changed, 68 insertions(+)
 create mode 100644 crates/examples/src/datafusion_read_data.rs
 create mode 100644 crates/examples/src/utils.rs

diff --git a/crates/examples/src/datafusion_read_data.rs b/crates/examples/src/datafusion_read_data.rs
new file mode 100644
index 000000000..56fac6251
--- /dev/null
+++ b/crates/examples/src/datafusion_read_data.rs
@@ -0,0 +1,37 @@
+// 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::prelude::SessionContext;
+use iceberg_datafusion::IcebergCatalogProvider;
+
+mod utils;
+
+#[tokio::main]
+async fn main() {
+    let iceberg_catalog = utils::get_rest_catalog();
+
+    let client = Arc::new(iceberg_catalog);
+    let catalog = Arc::new(IcebergCatalogProvider::try_new(client).await.unwrap());
+
+    let ctx = SessionContext::new();
+    ctx.register_catalog("catalog", catalog);
+    let df = ctx.sql("select * from catalog.ns.table1").await.unwrap();
+    let data = df.collect().await.unwrap();
+    println!("{:?}", data);
+}
diff --git a/crates/examples/src/utils.rs b/crates/examples/src/utils.rs
new file mode 100644
index 000000000..2784314f0
--- /dev/null
+++ b/crates/examples/src/utils.rs
@@ -0,0 +1,31 @@
+// 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::env;
+
+use iceberg_catalog_rest::{RestCatalog, RestCatalogConfig};
+
+fn get_catalog_uri_from_env() -> String {
+    env::var("CATALOG_URI").unwrap_or("http://localhost:8080".to_string())
+}
+
+pub fn get_rest_catalog() -> RestCatalog {
+    let config = RestCatalogConfig::builder()
+        .uri(get_catalog_uri_from_env())
+        .build();
+    RestCatalog::new(config)
+}