feat: implement metrics support

crates/ctl/src/cli/metrics.rs

@@ -0,0 +1,90 @@
+use anyhow::Result;
+use clap::{Parser, ValueEnum};
+use comfy_table::{presets::UTF8_FULL_CONDENSED, Table};
+use krata::{
+    events::EventStream,
+    v1::control::{
+        control_service_client::ControlServiceClient, ReadGuestMetricsReply,
+        ReadGuestMetricsRequest,
+    },
+};
+
+use tonic::transport::Channel;
+
+use crate::format::{kv2line, proto2dynamic, proto2kv};
+
+use super::resolve_guest;
+
+#[derive(ValueEnum, Clone, Debug, PartialEq, Eq)]
+enum MetricsFormat {
+    Table,
+    Json,
+    JsonPretty,
+    Yaml,
+    KeyValue,
+}
+
+#[derive(Parser)]
+#[command(about = "Read metrics from the guest")]
+pub struct MetricsCommand {
+    #[arg(short, long, default_value = "table", help = "Output format")]
+    format: MetricsFormat,
+    #[arg(help = "Guest to read metrics for, either the name or the uuid")]
+    guest: String,
+}
+
+impl MetricsCommand {
+    pub async fn run(
+        self,
+        mut client: ControlServiceClient<Channel>,
+        _events: EventStream,
+    ) -> Result<()> {
+        let guest_id: String = resolve_guest(&mut client, &self.guest).await?;
+        let reply = client
+            .read_guest_metrics(ReadGuestMetricsRequest { guest_id })
+            .await?
+            .into_inner();
+        match self.format {
+            MetricsFormat::Table => {
+                self.print_metrics_table(reply)?;
+            }
+
+            MetricsFormat::Json | MetricsFormat::JsonPretty | MetricsFormat::Yaml => {
+                let value = serde_json::to_value(proto2dynamic(reply)?)?;
+                let encoded = if self.format == MetricsFormat::JsonPretty {
+                    serde_json::to_string_pretty(&value)?
+                } else if self.format == MetricsFormat::Yaml {
+                    serde_yaml::to_string(&value)?
+                } else {
+                    serde_json::to_string(&value)?
+                };
+                println!("{}", encoded.trim());
+            }
+
+            MetricsFormat::KeyValue => {
+                self.print_key_value(reply)?;
+            }
+        }
+
+        Ok(())
+    }
+
+    fn print_metrics_table(&self, reply: ReadGuestMetricsReply) -> Result<()> {
+        let mut table = Table::new();
+        table.load_preset(UTF8_FULL_CONDENSED);
+        table.set_content_arrangement(comfy_table::ContentArrangement::Dynamic);
+        table.set_header(vec!["metric", "value"]);
+        let kvs = proto2kv(reply)?;
+        for (key, value) in kvs {
+            table.add_row(vec![key, value]);
+        }
+        println!("{}", table);
+        Ok(())
+    }
+
+    fn print_key_value(&self, metrics: ReadGuestMetricsReply) -> Result<()> {
+        let kvs = proto2kv(metrics)?;
+        println!("{}", kv2line(kvs),);
+        Ok(())
+    }
+}

crates/ctl/src/cli/mod.rs

@@ -3,6 +3,7 @@ pub mod destroy;
 pub mod launch;
 pub mod list;
 pub mod logs;
+pub mod metrics;
 pub mod resolve;
 pub mod watch;
 
@@ -17,7 +18,7 @@ use tonic::{transport::Channel, Request};
 
 use self::{
     attach::AttachCommand, destroy::DestroyCommand, launch::LauchCommand, list::ListCommand,
-    logs::LogsCommand, resolve::ResolveCommand, watch::WatchCommand,
+    logs::LogsCommand, metrics::MetricsCommand, resolve::ResolveCommand, watch::WatchCommand,
 };
 
 #[derive(Parser)]
@@ -47,6 +48,7 @@ pub enum Commands {
     Logs(LogsCommand),
     Watch(WatchCommand),
     Resolve(ResolveCommand),
+    Metrics(MetricsCommand),
 }
 
 impl ControlCommand {
@@ -82,6 +84,10 @@ impl ControlCommand {
             Commands::Resolve(resolve) => {
                 resolve.run(client).await?;
             }
+
+            Commands::Metrics(metrics) => {
+                metrics.run(client, events).await?;
+            }
         }
         Ok(())
     }