Rust: Add proper hello-world for Aurora (#5605)

* Rust: Add proper hello-world for Aurora

.doc_gen/metadata/aurora_metadata.yaml

@@ -39,10 +39,8 @@ aurora_Hello:
         - sdk_version: 1
           github: rust_dev_preview/examples/aurora
           excerpts:
-            - snippet_tags:
-                - rust.aurora.get_cluster.usage
-                - rust.aurora.describe_db_clusters.wrapper
-                - rust.aurora.get_cluster.test
+            - snippet_files:
+                - rust_dev_preview/examples/aurora/src/bin/hello-world.rs
   services:
     aurora: {DescribeDBClusters}
 aurora_DescribeDBClusterParameterGroups:

rust_dev_preview/examples/aurora/src/bin/hello-world.rs

@@ -0,0 +1,39 @@
+use aws_sdk_rds::Client;
+
+#[derive(Debug)]
+struct Error(String);
+impl std::fmt::Display for Error {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        write!(f, "{}", self.0)
+    }
+}
+impl std::error::Error for Error {}
+
+#[tokio::main]
+async fn main() -> Result<(), Error> {
+    tracing_subscriber::fmt::init();
+    let sdk_config = aws_config::from_env().load().await;
+    let client = Client::new(&sdk_config);
+
+    let describe_db_clusters_output = client
+        .describe_db_clusters()
+        .send()
+        .await
+        .map_err(|e| Error(e.to_string()))?;
+    println!(
+        "Found {} clusters:",
+        describe_db_clusters_output.db_clusters().len()
+    );
+    for cluster in describe_db_clusters_output.db_clusters() {
+        let name = cluster.database_name().unwrap_or("Unknown");
+        let engine = cluster.engine().unwrap_or("Unknown");
+        let id = cluster.db_cluster_identifier().unwrap_or("Unknown");
+        let class = cluster.db_cluster_instance_class().unwrap_or("Unknown");
+        println!("\tDatabase: {name}",);
+        println!("\t  Engine: {engine}",);
+        println!("\t      ID: {id}",);
+        println!("\tInstance: {class}",);
+    }
+
+    Ok(())
+}