Add simple example (#77)

Author: Kimahriman

README.md

@@ -86,4 +86,11 @@ then you can run the benchmarks with
 cargo bench -p hdfs-native --features benchmark
 ```
 
-The `benchmark` feature is required to expose `minidfs` and the internal erasure coding functions to benchmark.
+The `benchmark` feature is required to expose `minidfs` and the internal erasure coding functions to benchmark.
+
+## Running examples
+The examples make use of the `minidfs` module to create a simple HDFS cluster to run the example. This requires including the `integration-test` feature to enable the `minidfs` module. Alternatively, if you want to run the example against an existing HDFS cluster you can exclude the `integration-test` feature and make sure your `HADOOP_CONF_DIR` points to a directory with HDFS configs for talking to your cluster.
+
+```bash
+cargo run --example simple --features integration-test
+```

crates/hdfs-native/examples/simple.rs

@@ -0,0 +1,65 @@
+use std::collections::HashSet;
+
+#[cfg(feature = "integration-test")]
+use hdfs_native::minidfs::MiniDfs;
+use hdfs_native::{Client, WriteOptions};
+
+#[tokio::main]
+async fn main() {
+    let _ = env_logger::builder().format_timestamp_millis().try_init();
+
+    // If using the integration-test feature, create a MiniDFS cluster. Otherwise
+    // assume the environment has configs pointing to an existing HDFS cluster.
+    #[cfg(feature = "integration-test")]
+    let _dfs = MiniDfs::with_features(&HashSet::new());
+
+    let client = Client::default();
+
+    // Create an empty file
+    client
+        .create("/hdfs-native-test", WriteOptions::default())
+        .await
+        .unwrap()
+        .close()
+        .await
+        .unwrap();
+
+    // List files
+    let listing = client.list_status("/", false).await.unwrap();
+    println!("{:?}", listing);
+
+    // Get info on a specific file
+    let status = client.get_file_info("/hdfs-native-test").await.unwrap();
+    println!("{:?}", status);
+
+    // Rename a file
+    client
+        .rename("/hdfs-native-test", "/hdfs-native-test2", false)
+        .await
+        .unwrap();
+
+    // Delete a file
+    client.delete("/hdfs-native-test2", false).await.unwrap();
+
+    // Write to a new file
+    let mut writer = client
+        .create("/hdfs-native-write", WriteOptions::default())
+        .await
+        .unwrap();
+
+    writer.write(vec![1, 2, 3, 4].into()).await.unwrap();
+    writer.close().await.unwrap();
+
+    // Append to an existing file
+    let mut writer = client.append("/hdfs-native-write").await.unwrap();
+
+    writer.write(vec![5, 6, 7, 8].into()).await.unwrap();
+    writer.close().await.unwrap();
+
+    // Read a file
+    let reader = client.read("/hdfs-native-write").await.unwrap();
+    let content = reader.read_range(0, reader.file_length()).await.unwrap();
+    println!("{:?}", content);
+
+    client.delete("/hdfs-native-write", false).await.unwrap();
+}