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# Rust Native API

Apache IoTDB provides an official Rust client SDK: [apache/iotdb-client-rust](https://github.com/apache/iotdb-client-rust). It speaks the Thrift RPC protocol (default port 6667). This document covers the **table model** (`TableSession` / `TableSessionPool`, relational SQL dialect); the tree model is documented separately.

## 1. Requirements

- Rust 1.75+
- Apache IoTDB 2.x — see [COMPATIBILITY.md](https://github.com/apache/iotdb-client-rust/blob/main/COMPATIBILITY.md) for the full server version matrix

## 2. Installation

Once published to crates.io:

```toml
[dependencies]
iotdb-client-rust = "0.1"
```

Until then, use a git dependency:

```toml
[dependencies]
iotdb-client = { git = "https://github.com/apache/iotdb-client-rust" }
```

The import name is `iotdb_client` in both cases.

## 3. Quick start

```rust
use iotdb_client::{ColumnCategory, Result, TSDataType, TableSession, Tablet, Value};

fn main() -> Result<()> {
    let mut session = TableSession::builder()
        .node_urls(&["127.0.0.1:6667"])?
        .username("root")
        .password("root")
        .build()?;

    session.execute_non_query("CREATE DATABASE IF NOT EXISTS demo")?;
    session.execute_non_query("USE demo")?;
    session.execute_non_query(
        "CREATE TABLE IF NOT EXISTS sensors (device_id STRING TAG, temperature DOUBLE FIELD)",
    )?;

    // Column-major tablet write. columnCategories must NOT include TIME —
    // the time column is implicit.
    let mut tablet = Tablet::new_table(
        "sensors",
        vec!["device_id".into(), "temperature".into()],
        vec![TSDataType::String, TSDataType::Double],
        vec![ColumnCategory::Tag, ColumnCategory::Field],
    )?;
    tablet.add_row(
        1_720_000_000_000,
        vec![
            Some(Value::String("dev-1".into())),
            Some(Value::Double(21.5)),
        ],
    )?;
    session.insert(&tablet)?;

    // Query with row iteration; the dataset borrows the session until dropped.
    {
        let mut dataset =
            session.execute_query("SELECT time, device_id, temperature FROM sensors")?;
        while let Some(row) = dataset.next_row()? {
            println!("{:?}", row.values);
        }
    }

    session.execute_non_query("DROP DATABASE demo")?;
    session.close()
}
```

## 4. Session pool

`TableSessionPool` is the thread-safe pool variant for concurrent workloads; `acquire()` returns an RAII guard that releases the session back to the pool on drop. See the runnable [`session_pool` example](https://github.com/apache/iotdb-client-rust/blob/main/examples/session_pool.rs).

## 5. TLS & RPC compression

**RPC compression** (the Thrift compact protocol) must match the server setting `dn_rpc_thrift_compression_enable` (default `false`):

```rust
let mut session = TableSession::builder()
    .node_urls(&["127.0.0.1:6667"])?
    .enable_rpc_compression(true)
    .build()?;
```

**TLS** is behind the `tls` cargo feature:

```toml
iotdb-client-rust = { version = "0.1", features = ["tls"] }
```

```rust
let mut session = TableSession::builder()
    .node_urls(&["127.0.0.1:6667"])?
    .use_ssl(true)
    .ca_cert_path("ca.pem")
    .build()?;
```

## 6. Examples

Full runnable examples live in the repository's [`examples/`](https://github.com/apache/iotdb-client-rust/tree/main/examples) directory:

```sh
cargo run --example table_session
cargo run --example session_pool
```