datum-cli 0.10.3

Command-line interface for the Datum Control Protocol
Documentation
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use std::{
    future::Future,
    net::{IpAddr, Ipv4Addr, SocketAddr, TcpListener as StdTcpListener},
    path::PathBuf,
    process::{Command, Output, Stdio},
    time::{Duration, Instant},
};

use datum::{Keep, Sink, Source};
use datum_agent::{
    Agent, AgentConfig, ClusterAgent, ClusterAgentConfig, ClusterAgentHandle, JobMat, JobSpec,
    NodeSessionConfig, NodeSessionTransport,
    dcp::{
        ClientKind, DcpClient, DcpJobFactories, DcpServer, DcpServerConfig, DcpServerHandle,
        DcpTcpServerConfig, Hello, proto::DcpFrame,
    },
};
use datum_cluster::{ClusterConfig, MemberState};
use prost::Message as ProstMessage;
use serde_json::Value;
use tokio::{
    io::{AsyncBufReadExt, AsyncRead, AsyncReadExt, AsyncWrite, AsyncWriteExt, BufReader},
    net::TcpListener,
    process::Command as TokioCommand,
};

struct TestDaemon {
    agent: datum_agent::AgentHandle,
    handle: DcpServerHandle,
    addr: SocketAddr,
}

impl TestDaemon {
    async fn start() -> Self {
        let agent = Agent::start_with_config(AgentConfig {
            poll_interval: Duration::from_millis(5),
            event_buffer: 128,
            ..AgentConfig::default()
        })
        .expect("agent starts");
        let server = DcpServer::from_agent(
            &agent,
            factories(),
            DcpServerConfig {
                node_id: "cli-test-agent".to_owned(),
                tcp: Some(DcpTcpServerConfig {
                    addr: SocketAddr::new(IpAddr::V4(Ipv4Addr::LOCALHOST), 0),
                }),
                quic: None,
                auth_token: None,
                metrics_interval: Duration::from_millis(10),
                frame_buffer: 128,
            },
        );
        let handle = server.start().await.expect("DCP server starts");
        let addr = handle.tcp_addr().expect("TCP listener address");
        Self {
            agent,
            handle,
            addr,
        }
    }

    async fn shutdown(self) {
        self.handle.shutdown().await;
        self.agent
            .registry()
            .shutdown()
            .expect("registry shuts down");
    }
}

struct TestCluster {
    nodes: Vec<ClusterAgentHandle>,
}

impl TestCluster {
    async fn start(count: usize) -> Self {
        let mut nodes = Vec::new();
        for index in 0..count {
            let seeds = nodes
                .first()
                .map(|node: &ClusterAgentHandle| vec![node.cluster().advertise_addr()])
                .unwrap_or_default();
            let config = cluster_agent_config(&format!("node-{index}"), seeds);
            nodes.push(
                ClusterAgent::start(config, factories())
                    .await
                    .expect("cluster agent starts"),
            );
        }
        wait_cluster_up(&nodes, count).await;
        let client = DcpClient::connect_tcp(
            nodes[0].tcp_addr().expect("node 0 TCP"),
            Hello::new("cli-test", ClientKind::Cli),
        )
        .await
        .expect("cluster client connects");
        wait_cluster_sessions(&client, count).await;
        Self { nodes }
    }

    async fn shutdown(self) {
        for node in self.nodes {
            let _ = node.shutdown().await;
        }
    }
}

fn cluster_agent_config(node_id: &str, seed_nodes: Vec<SocketAddr>) -> ClusterAgentConfig {
    ClusterAgentConfig {
        agent: AgentConfig {
            poll_interval: Duration::from_millis(5),
            event_buffer: 128,
            ..AgentConfig::default()
        },
        cluster: ClusterConfig {
            node_id: node_id.to_owned(),
            roles: vec!["agent".to_owned()],
            bind_addr: SocketAddr::new(IpAddr::V4(Ipv4Addr::LOCALHOST), 0),
            advertise_addr: SocketAddr::new(IpAddr::V4(Ipv4Addr::LOCALHOST), 0),
            seed_nodes,
            gossip_interval: Duration::from_millis(60),
            probe_timeout: Duration::from_millis(15),
            suspect_timeout: Duration::from_secs(2),
            downing_timeout: Duration::from_millis(150),
            remove_down_after: Duration::from_secs(20),
            event_buffer: 512,
            ..ClusterConfig::default()
        },
        dcp: DcpServerConfig {
            node_id: node_id.to_owned(),
            tcp: Some(DcpTcpServerConfig {
                addr: SocketAddr::new(IpAddr::V4(Ipv4Addr::LOCALHOST), 0),
            }),
            quic: None,
            auth_token: None,
            metrics_interval: Duration::from_millis(10),
            frame_buffer: 128,
        },
        sessions: NodeSessionConfig {
            transport: NodeSessionTransport::TcpLoopback,
            reconnect_min_backoff: Duration::from_millis(20),
            reconnect_max_backoff: Duration::from_millis(100),
            request_timeout: Duration::from_millis(300),
            command_buffer: 16,
            ..NodeSessionConfig::default()
        },
    }
}

fn factories() -> DcpJobFactories {
    let factories = DcpJobFactories::new();
    factories
        .register("ticker", |instance_name, _params| {
            Ok(JobSpec::new(instance_name, |context| {
                let control = context.control();
                Ok(
                    Source::tick(Duration::ZERO, Duration::from_millis(10), 1_u64)
                        .instrumented(
                            format!("{}:{}", context.name(), context.generation()),
                            context.instrumentation_registry(),
                        )
                        .via_mat(context.drain_flow(), Keep::right)
                        .to_mat(Sink::ignore(), move |_switch, completion| {
                            JobMat::new(completion, control.clone())
                        }),
                )
            }))
        })
        .expect("ticker factory registers");
    factories
        .register("empty", |instance_name, _params| {
            Ok(JobSpec::new(instance_name, |context| {
                let control = context.control();
                Ok(Source::<u64>::empty()
                    .instrumented(
                        format!("{}:{}", context.name(), context.generation()),
                        context.instrumentation_registry(),
                    )
                    .via_mat(context.drain_flow(), Keep::right)
                    .to_mat(Sink::ignore(), move |_switch, completion| {
                        JobMat::new(completion, control.clone())
                    }))
            }))
        })
        .expect("empty factory registers");
    factories
}

async fn wait_cluster_up(nodes: &[ClusterAgentHandle], expected: usize) {
    wait_until(Duration::from_secs(8), || async {
        nodes.iter().all(|node| {
            let state = node.cluster().current_state();
            state.members.len() == expected
                && state
                    .members
                    .values()
                    .all(|member| member.state == MemberState::Up && !member.unreachable)
        })
    })
    .await;
}

async fn wait_cluster_sessions(client: &DcpClient, expected: usize) {
    wait_until(Duration::from_secs(8), || async {
        client
            .cluster_node_info(1_000)
            .await
            .ok()
            .is_some_and(|info| {
                info.nodes.len() == expected
                    && info
                        .nodes
                        .iter()
                        .filter(|node| !node.local)
                        .all(|node| node.session_state == "connected")
            })
    })
    .await;
}

async fn wait_until<Fut>(timeout: Duration, mut condition: impl FnMut() -> Fut)
where
    Fut: Future<Output = bool>,
{
    let deadline = Instant::now() + timeout;
    while Instant::now() < deadline {
        if condition().await {
            return;
        }
        tokio::time::sleep(Duration::from_millis(10)).await;
    }
    assert!(condition().await, "condition timed out");
}

fn datum_bin() -> PathBuf {
    PathBuf::from(env!("CARGO_BIN_EXE_datum"))
}

fn run_datum(addr: SocketAddr, args: &[&str]) -> Output {
    Command::new(datum_bin())
        .arg("--addr")
        .arg(addr.to_string())
        .args(args)
        .output()
        .expect("datum process runs")
}

fn assert_success(output: &Output) {
    assert!(
        output.status.success(),
        "expected success\nstdout:\n{}\nstderr:\n{}",
        String::from_utf8_lossy(&output.stdout),
        String::from_utf8_lossy(&output.stderr)
    );
}

fn stdout(output: &Output) -> String {
    String::from_utf8(output.stdout.clone()).expect("stdout is UTF-8")
}

fn stderr(output: &Output) -> String {
    String::from_utf8(output.stderr.clone()).expect("stderr is UTF-8")
}

async fn stop_child(child: &mut tokio::process::Child) {
    let _ = child.start_kill();
    let _ = tokio::time::timeout(Duration::from_secs(1), child.wait()).await;
}

#[tokio::test(flavor = "multi_thread", worker_threads = 2)]
async fn lifecycle_commands_and_json_snapshots() {
    let daemon = TestDaemon::start().await;

    let output = run_datum(daemon.addr, &["--json", "ps"]);
    assert_success(&output);
    assert_eq!(stdout(&output), "{\n  \"jobs\": []\n}\n");

    let output = run_datum(
        daemon.addr,
        &["start", "ticker", "--name", "ingest", "--param", "shard=0"],
    );
    assert_success(&output);
    assert!(stdout(&output).contains("started 'ingest' from factory 'ticker'"));

    let output = run_datum(daemon.addr, &["ps"]);
    assert_success(&output);
    let jobs_table = stdout(&output);
    assert!(jobs_table.contains("JOB"));
    assert!(jobs_table.contains("ingest"));
    assert!(jobs_table.contains("Running"));

    let output = run_datum(daemon.addr, &["--json", "status", "ingest"]);
    assert_success(&output);
    let status: Value = serde_json::from_slice(&output.stdout).expect("status JSON parses");
    assert_eq!(status["job"]["name"], "ingest");
    assert_eq!(status["job"]["state"], "Running");
    assert_eq!(status["job"]["generation"], 1);

    let output = run_datum(daemon.addr, &["--json", "restart", "ingest"]);
    assert_success(&output);
    let restarted: Value = serde_json::from_slice(&output.stdout).expect("restart JSON parses");
    assert_eq!(restarted["action"], "restarted");
    assert_eq!(restarted["job"]["name"], "ingest");
    assert_eq!(restarted["job"]["generation"], 2);

    let output = run_datum(daemon.addr, &["--json", "metrics", "ingest"]);
    assert_success(&output);
    let metrics: Value = serde_json::from_slice(&output.stdout).expect("metrics JSON parses");
    assert_eq!(metrics["job"], "ingest");
    assert!(
        metrics["sample"]["streams"]
            .as_array()
            .expect("metric streams array")
            .iter()
            .any(|stream| stream["name"]
                .as_str()
                .is_some_and(|name| name.starts_with("ingest:")))
    );

    let output = run_datum(daemon.addr, &["drain", "ingest"]);
    assert_success(&output);
    assert!(stdout(&output).contains("drained 'ingest'"));

    let output = run_datum(daemon.addr, &["start", "ticker", "--name", "stop-me"]);
    assert_success(&output);
    let output = run_datum(daemon.addr, &["--json", "stop", "stop-me"]);
    assert_success(&output);
    let stopped: Value = serde_json::from_slice(&output.stdout).expect("stop JSON parses");
    assert_eq!(stopped["action"], "stopped");
    assert_eq!(stopped["job"]["state"], "Stopped");

    daemon.shutdown().await;
}

#[tokio::test(flavor = "multi_thread", worker_threads = 4)]
async fn cluster_ps_and_nodes_use_cluster_dcp_requests() {
    let cluster = TestCluster::start(2).await;
    let node0 = cluster.nodes[0].tcp_addr().expect("node 0 TCP");
    let node1 = cluster.nodes[1].tcp_addr().expect("node 1 TCP");

    let output = run_datum(node1, &["start", "ticker", "--name", "remote-job"]);
    assert_success(&output);

    let output = run_datum(
        node0,
        &[
            "submit",
            "--cluster",
            "--factory",
            "ticker",
            "--name",
            "placed-job",
            "--node",
            "node-1",
        ],
    );
    assert_success(&output);
    assert!(stdout(&output).contains("submitted cluster job 'placed-job'"));

    let output = run_datum(node0, &["nodes"]);
    assert_success(&output);
    let nodes_table = stdout(&output);
    assert!(nodes_table.contains("NODE"));
    assert!(nodes_table.contains("node-0"));
    assert!(nodes_table.contains("node-1"));
    assert!(nodes_table.contains("connected"));

    let output = run_datum(node0, &["ps", "--cluster"]);
    assert_success(&output);
    let jobs_table = stdout(&output);
    assert!(jobs_table.contains("NODE"));
    assert!(jobs_table.contains("node-1"));
    assert!(jobs_table.contains("remote-job"));
    assert!(jobs_table.contains("placed-job"));
    assert!(jobs_table.contains("PLACED_ON"));

    cluster.shutdown().await;
}

#[tokio::test(flavor = "multi_thread", worker_threads = 2)]
async fn events_command_tails_subscription() {
    let daemon = TestDaemon::start().await;
    let child = TokioCommand::new(datum_bin())
        .arg("--addr")
        .arg(daemon.addr.to_string())
        .arg("events")
        .stdout(Stdio::piped())
        .spawn()
        .expect("events command starts");

    tokio::time::sleep(Duration::from_millis(100)).await;
    let output = run_datum(daemon.addr, &["start", "ticker", "--name", "event-job"]);
    assert_success(&output);

    let output = tokio::time::timeout(Duration::from_secs(4), child.wait_with_output())
        .await
        .expect("events command exits after idle")
        .expect("events output");
    assert_success(&output);
    let output = stdout(&output);
    assert!(output.contains("event-job"));
    assert!(output.contains("Submitted") || output.contains("Started"));

    daemon.shutdown().await;
}

#[tokio::test(flavor = "multi_thread", worker_threads = 2)]
async fn follow_streams_emit_json_lines() {
    let daemon = TestDaemon::start().await;

    let mut child = TokioCommand::new(datum_bin())
        .arg("--addr")
        .arg(daemon.addr.to_string())
        .arg("--json")
        .arg("events")
        .arg("--follow")
        .stdout(Stdio::piped())
        .spawn()
        .expect("events --follow command starts");
    tokio::time::sleep(Duration::from_millis(100)).await;
    let output = run_datum(daemon.addr, &["start", "ticker", "--name", "follow-events"]);
    assert_success(&output);

    let stdout = child.stdout.take().expect("event stdout is piped");
    let mut reader = BufReader::new(stdout);
    let mut line = String::new();
    tokio::time::timeout(Duration::from_secs(4), reader.read_line(&mut line))
        .await
        .expect("event line arrives")
        .expect("event line reads");
    drop(reader);
    stop_child(&mut child).await;
    let event: Value = serde_json::from_str(&line).expect("event JSON line parses");
    assert_eq!(event["event"]["name"], "follow-events");

    let output = run_datum(
        daemon.addr,
        &["start", "ticker", "--name", "follow-metrics"],
    );
    assert_success(&output);
    let mut child = TokioCommand::new(datum_bin())
        .arg("--addr")
        .arg(daemon.addr.to_string())
        .arg("--json")
        .arg("metrics")
        .arg("follow-metrics")
        .arg("--follow")
        .stdout(Stdio::piped())
        .spawn()
        .expect("metrics --follow command starts");
    let stdout = child.stdout.take().expect("metric stdout is piped");
    let mut reader = BufReader::new(stdout);
    let mut line = String::new();
    tokio::time::timeout(Duration::from_secs(4), reader.read_line(&mut line))
        .await
        .expect("metric line arrives")
        .expect("metric line reads");
    drop(reader);
    stop_child(&mut child).await;
    let metric: Value = serde_json::from_str(&line).expect("metric JSON line parses");
    assert_eq!(metric["job"], "follow-metrics");
    assert!(
        metric["sample"]["streams"]
            .as_array()
            .expect("metric streams array")
            .iter()
            .any(|stream| stream["name"]
                .as_str()
                .is_some_and(|name| name.starts_with("follow-metrics:")))
    );

    daemon.shutdown().await;
}

#[tokio::test(flavor = "multi_thread", worker_threads = 2)]
async fn connect_failure_uses_exit_code_2_and_fix_text() {
    let listener = StdTcpListener::bind(SocketAddr::new(IpAddr::V4(Ipv4Addr::LOCALHOST), 0))
        .expect("ephemeral port binds");
    let addr = listener.local_addr().expect("listener address");
    drop(listener);

    let output = run_datum(addr, &["ps"]);
    assert_eq!(output.status.code(), Some(2));
    let stderr = stderr(&output);
    assert!(stderr.contains("could not connect to datum-agent"));
    assert!(stderr.contains("start datum-agent or pass --addr"));
}

#[tokio::test(flavor = "multi_thread", worker_threads = 2)]
async fn remote_errors_use_exit_code_1_and_fix_text() {
    let daemon = TestDaemon::start().await;

    let output = run_datum(daemon.addr, &["status", "missing"]);
    assert_eq!(output.status.code(), Some(1));
    let stderr = stderr(&output);
    assert!(stderr.contains("datum-agent rejected the request"));
    assert!(stderr.contains("Check the job or factory name with `datum ps`."));

    daemon.shutdown().await;
}

#[test]
fn usage_errors_use_exit_code_2() {
    let output = Command::new(datum_bin())
        .arg("start")
        .arg("ticker")
        .arg("--param")
        .arg("bad-param")
        .output()
        .expect("datum process runs");

    assert_eq!(output.status.code(), Some(2));
    assert!(stderr(&output).contains("invalid --param 'bad-param'"));
}

async fn recv_raw_frame<R: AsyncRead + Unpin>(reader: &mut R) -> std::io::Result<Option<DcpFrame>> {
    let mut header = [0_u8; 4];
    match reader.read_exact(&mut header).await {
        Ok(_) => {}
        Err(error) if error.kind() == std::io::ErrorKind::UnexpectedEof => return Ok(None),
        Err(error) => return Err(error),
    }
    let len = u32::from_be_bytes(header) as usize;
    if len == 0 || len > 16 * 1024 * 1024 {
        return Err(std::io::Error::new(
            std::io::ErrorKind::InvalidData,
            "bad frame length",
        ));
    }
    let mut payload = vec![0_u8; len];
    reader.read_exact(&mut payload).await?;
    Ok(Some(DcpFrame::decode(payload.as_slice()).map_err(|e| {
        std::io::Error::new(std::io::ErrorKind::InvalidData, e)
    })?))
}

async fn send_raw_frame<W: AsyncWrite + Unpin>(
    writer: &mut W,
    frame: &DcpFrame,
) -> std::io::Result<()> {
    let payload = frame.encode_to_vec();
    let len = u32::try_from(payload.len())
        .map_err(|_| std::io::Error::new(std::io::ErrorKind::InvalidData, "frame too large"))?;
    writer.write_all(&len.to_be_bytes()).await?;
    writer.write_all(&payload).await?;
    writer.flush().await
}

async fn accept_and_respond(listener: &TcpListener) {
    let (mut stream, _) = listener.accept().await.expect("accept");
    let hello = recv_raw_frame(&mut stream)
        .await
        .expect("read hello")
        .expect("hello frame");
    assert!(matches!(
        hello.frame,
        Some(datum_agent::dcp::proto::dcp_frame::Frame::Hello(_))
    ));
    let hello_resp = datum_agent::dcp::proto::Response::ok(0, Vec::new());
    send_raw_frame(&mut stream, &DcpFrame::response(hello_resp))
        .await
        .expect("write hello response");

    let subscribe = recv_raw_frame(&mut stream)
        .await
        .expect("read subscribe")
        .expect("subscribe frame");
    assert!(matches!(
        subscribe.frame,
        Some(datum_agent::dcp::proto::dcp_frame::Frame::Request(_))
    ));

    let subscribe_resp = datum_agent::dcp::proto::Response::ok(1, Vec::new());
    send_raw_frame(&mut stream, &DcpFrame::response(subscribe_resp))
        .await
        .expect("write subscribe response");

    drop(stream);
}

#[tokio::test(flavor = "multi_thread", worker_threads = 2)]
async fn events_follow_exits_nonzero_on_daemon_disconnect() {
    let listener = TcpListener::bind("127.0.0.1:0")
        .await
        .expect("bind listener");
    let addr = listener.local_addr().expect("listener addr");

    let server_task = tokio::spawn(async move {
        accept_and_respond(&listener).await;
    });

    let child = TokioCommand::new(datum_bin())
        .arg("--addr")
        .arg(addr.to_string())
        .arg("events")
        .arg("--follow")
        .stdout(Stdio::piped())
        .stderr(Stdio::piped())
        .spawn()
        .expect("events --follow command starts");

    server_task.await.expect("server completes handshake");

    let output = tokio::time::timeout(Duration::from_secs(8), child.wait_with_output())
        .await
        .expect("events --follow exits after disconnect")
        .expect("events output");
    assert!(
        !output.status.success(),
        "events --follow should exit non-zero on disconnect"
    );
    let err = String::from_utf8_lossy(&output.stderr);
    assert!(
        !err.is_empty(),
        "events --follow should print an error on disconnect, got empty stderr"
    );
}

#[tokio::test(flavor = "multi_thread", worker_threads = 2)]
async fn metrics_follow_exits_nonzero_on_daemon_disconnect() {
    let listener = TcpListener::bind("127.0.0.1:0")
        .await
        .expect("bind listener");
    let addr = listener.local_addr().expect("listener addr");

    let server_task = tokio::spawn(async move {
        accept_and_respond(&listener).await;
    });

    let child = TokioCommand::new(datum_bin())
        .arg("--addr")
        .arg(addr.to_string())
        .arg("metrics")
        .arg("any-job")
        .arg("--follow")
        .stdout(Stdio::piped())
        .stderr(Stdio::piped())
        .spawn()
        .expect("metrics --follow command starts");

    server_task.await.expect("server completes handshake");

    let output = tokio::time::timeout(Duration::from_secs(8), child.wait_with_output())
        .await
        .expect("metrics --follow exits after disconnect")
        .expect("metrics output");
    assert!(
        !output.status.success(),
        "metrics --follow should exit non-zero on disconnect"
    );
    let err = String::from_utf8_lossy(&output.stderr);
    assert!(
        !err.is_empty(),
        "metrics --follow should print an error on disconnect, got empty stderr"
    );
}