canic-cli 0.94.7

//! Module: metrics::transport
//!
//! Responsibility: collect typed metric observations for installed deployment canisters.
//! Does not own: metric DTOs, report rendering, or deployment registry authority.
//! Boundary: preserves query causes until projecting per-canister report diagnostics.

use crate::metrics::{
    CANIC_METRICS_METHOD, MetricsCommandError,
    model::{
        MetricEntry, MetricValue, MetricsCanisterReport, MetricsCanisterStatus, MetricsKind,
        MetricsReport,
    },
    options::MetricsOptions,
    parse::parse_metrics_page,
};
use crate::support::candid::registry_entry_candid_path;
use canic_host::{
    icp::{IcpCli, IcpCommandError, IcpDiagnostic, IcpJsonResponseError},
    icp_config::resolve_current_canic_icp_root,
    installed_deployment::{
        InstalledDeploymentRequest, InstalledDeploymentResolution,
        resolve_installed_deployment_from_root,
    },
    registry::RegistryEntry,
};
use std::{path::PathBuf, sync::Arc, thread};
use thiserror::Error as ThisError;

const METRICS_UNAVAILABLE_HINT: &str =
    "canic_metrics unavailable; check deployed Wasm and metrics profile";
const METRICS_EMPTY_HINT: &str =
    "no metrics rows; check whether this tier is enabled by the deployed role profile";
const METRICS_NONZERO_EMPTY_HINT: &str =
    "no nonzero metrics rows; rerun without --nonzero or check the deployed role profile";
const METRICS_WORKER_PANIC: &str = "metrics query worker panicked";

#[derive(Debug, ThisError)]
enum MetricsQueryError {
    #[error(transparent)]
    Icp(#[from] IcpCommandError),

    #[error("invalid canic_metrics response: {0}")]
    Response(#[source] IcpJsonResponseError),
}

pub(super) fn metrics_report(
    options: &MetricsOptions,
) -> Result<MetricsReport, MetricsCommandError> {
    let registry = load_registry(options)?;
    let canisters = collect_metrics_reports(options, &registry);

    Ok(MetricsReport {
        deployment: options.deployment.clone(),
        environment: options.environment.clone(),
        kind: options.kind,
        canisters,
    })
}

fn load_registry(options: &MetricsOptions) -> Result<Vec<RegistryEntry>, MetricsCommandError> {
    let mut registry = resolve_metrics_deployment(options)?.registry.entries;
    registry.retain(|entry| matches_metrics_filter(options, entry));
    Ok(registry)
}

fn matches_metrics_filter(options: &MetricsOptions, entry: &RegistryEntry) -> bool {
    if let Some(role) = &options.role
        && entry.role.as_deref() != Some(role.as_str())
    {
        return false;
    }
    if let Some(canister) = &options.canister
        && entry.pid != *canister
    {
        return false;
    }
    true
}

fn collect_metrics_reports(
    options: &MetricsOptions,
    registry: &[RegistryEntry],
) -> Vec<MetricsCanisterReport> {
    let query = Arc::new(options.clone());
    let mut handles = Vec::new();
    for entry in registry {
        let entry = entry.clone();
        let worker_entry = entry.clone();
        let query = Arc::clone(&query);
        handles.push((
            worker_entry,
            thread::spawn(move || metrics_canister_report(&query, &entry)),
        ));
    }

    collect_metrics_worker_reports(handles)
}

fn collect_metrics_worker_reports(
    handles: Vec<(RegistryEntry, thread::JoinHandle<MetricsCanisterReport>)>,
) -> Vec<MetricsCanisterReport> {
    handles
        .into_iter()
        .map(|(entry, handle)| {
            handle
                .join()
                .unwrap_or_else(|_| metrics_message_error_report(&entry, METRICS_WORKER_PANIC))
        })
        .collect()
}

fn metrics_canister_report(
    options: &MetricsOptions,
    entry: &RegistryEntry,
) -> MetricsCanisterReport {
    match query_metrics(options, entry) {
        Ok(mut entries) => {
            if options.nonzero {
                entries.retain(|entry| !metric_value_is_zero(&entry.value));
            }
            if entries.is_empty() {
                return metrics_empty_report(entry, options.nonzero);
            }
            MetricsCanisterReport {
                role: entry.role.clone().unwrap_or_else(|| "-".to_string()),
                canister_id: entry.pid.clone(),
                status: MetricsCanisterStatus::Ok,
                entries,
                error: None,
            }
        }
        Err(error) => metrics_query_error_report(entry, &error),
    }
}

fn metrics_empty_report(entry: &RegistryEntry, nonzero: bool) -> MetricsCanisterReport {
    MetricsCanisterReport {
        role: entry.role.clone().unwrap_or_else(|| "-".to_string()),
        canister_id: entry.pid.clone(),
        status: MetricsCanisterStatus::Empty,
        entries: Vec::new(),
        error: Some(
            if nonzero {
                METRICS_NONZERO_EMPTY_HINT
            } else {
                METRICS_EMPTY_HINT
            }
            .to_string(),
        ),
    }
}

fn metrics_query_error_report(
    entry: &RegistryEntry,
    error: &MetricsQueryError,
) -> MetricsCanisterReport {
    if matches!(
        error,
        MetricsQueryError::Icp(error)
            if matches!(error.diagnostic(), Some(IcpDiagnostic::MethodMissing))
    ) {
        return metrics_failure_report(
            entry,
            MetricsCanisterStatus::Unavailable,
            METRICS_UNAVAILABLE_HINT,
        );
    }

    let error = error.to_string();
    metrics_failure_report(
        entry,
        MetricsCanisterStatus::Error,
        error.lines().next().unwrap_or(&error),
    )
}

fn metrics_message_error_report(entry: &RegistryEntry, error: &str) -> MetricsCanisterReport {
    metrics_failure_report(
        entry,
        MetricsCanisterStatus::Error,
        error.lines().next().unwrap_or(error),
    )
}

fn metrics_failure_report(
    entry: &RegistryEntry,
    status: MetricsCanisterStatus,
    error: &str,
) -> MetricsCanisterReport {
    MetricsCanisterReport {
        role: entry.role.clone().unwrap_or_else(|| "-".to_string()),
        canister_id: entry.pid.clone(),
        status,
        entries: Vec::new(),
        error: Some(error.to_string()),
    }
}

const fn metric_value_is_zero(value: &MetricValue) -> bool {
    match value {
        MetricValue::Count { count } => *count == 0,
        MetricValue::CountAndU64 { count, value_u64 } => *count == 0 && *value_u64 == 0,
        MetricValue::U128 { value } => *value == 0,
    }
}

const fn metrics_kind_candid_variant(kind: MetricsKind) -> &'static str {
    match kind {
        MetricsKind::Core => "Core",
        MetricsKind::Placement => "Placement",
        MetricsKind::Platform => "Platform",
        MetricsKind::Runtime => "Runtime",
        MetricsKind::Security => "Security",
        MetricsKind::Storage => "Storage",
    }
}

fn query_metrics(
    options: &MetricsOptions,
    entry: &RegistryEntry,
) -> Result<Vec<MetricEntry>, MetricsQueryError> {
    let arg = format!(
        "(variant {{ {} }}, record {{ offset = 0 : nat64; limit = {} : nat64 }})",
        metrics_kind_candid_variant(options.kind),
        options.limit
    );
    let mut icp = IcpCli::new(&options.icp, Some(options.environment.clone()));
    let root = resolve_metrics_icp_root();
    let candid_path = registry_entry_candid_path(root.as_deref(), &options.environment, entry);
    if let Some(root) = root {
        icp = icp.with_cwd(root);
    }
    let output = icp.canister_query_arg_output_with_candid(
        &entry.pid,
        CANIC_METRICS_METHOD,
        &arg,
        Some("json"),
        candid_path.as_deref(),
    )?;

    parse_metrics_page(&output).map_err(MetricsQueryError::Response)
}

fn resolve_metrics_deployment(
    options: &MetricsOptions,
) -> Result<InstalledDeploymentResolution, MetricsCommandError> {
    let root = resolve_current_canic_icp_root().map_err(MetricsCommandError::IcpRoot)?;
    resolve_installed_deployment_from_root(
        &InstalledDeploymentRequest {
            deployment: options.deployment.clone(),
            environment: options.environment.clone(),
            icp: options.icp.clone(),
            detect_lost_local_root: false,
        },
        &root,
    )
    .map_err(MetricsCommandError::from)
}

fn resolve_metrics_icp_root() -> Option<PathBuf> {
    resolve_current_canic_icp_root().ok()
}

#[cfg(test)]
mod tests {
    use super::*;

    fn registry_entry() -> RegistryEntry {
        RegistryEntry {
            pid: "aaaaa-aa".to_string(),
            role: Some("wasm_store".to_string()),
            parent_pid: None,
            module_hash: None,
        }
    }

    // Ensure method-missing responses do not stretch the table with raw ICP output.
    #[test]
    fn shortens_metrics_unavailable_errors() {
        let error = MetricsQueryError::Icp(IcpCommandError::Failed {
            command: "icp canister call".to_string(),
            stderr: "Canister has no query method 'canic_metrics'.".to_string(),
        });
        let report = metrics_query_error_report(&registry_entry(), &error);

        assert_eq!(report.status, MetricsCanisterStatus::Unavailable);
        assert_eq!(
            serde_json::to_value(&report).expect("serialize metrics report")["status"],
            "unavailable"
        );
        assert_eq!(report.error.as_deref(), Some(METRICS_UNAVAILABLE_HINT));
    }

    // Ensure empty successful metric tiers point operators at profile/deployed-Wasm checks.
    #[test]
    fn empty_metrics_reports_carry_profile_hint() {
        let report = metrics_empty_report(&registry_entry(), false);

        assert_eq!(report.status, MetricsCanisterStatus::Empty);
        assert_eq!(
            serde_json::to_value(&report).expect("serialize metrics report")["status"],
            "empty"
        );
        assert_eq!(report.error.as_deref(), Some(METRICS_EMPTY_HINT));

        let filtered = metrics_empty_report(&registry_entry(), true);
        assert_eq!(filtered.status, MetricsCanisterStatus::Empty);
        assert_eq!(filtered.error.as_deref(), Some(METRICS_NONZERO_EMPTY_HINT));
    }

    // Ensure zero filtering treats every payload shape consistently.
    #[test]
    fn detects_zero_metric_values() {
        assert!(metric_value_is_zero(&MetricValue::Count { count: 0 }));
        assert!(metric_value_is_zero(&MetricValue::CountAndU64 {
            count: 0,
            value_u64: 0
        }));
        assert!(!metric_value_is_zero(&MetricValue::U128 { value: 1 }));
    }

    // Ensure transport preserves the Candid metric kind vocabulary.
    #[test]
    fn maps_metric_kind_to_candid_variant() {
        assert_eq!(
            metrics_kind_candid_variant(MetricsKind::Security),
            "Security"
        );
    }

    #[test]
    fn panicked_metrics_worker_becomes_an_explicit_canister_error() {
        let entry = registry_entry();
        let reports = collect_metrics_worker_reports(vec![(
            entry.clone(),
            thread::spawn(|| panic!("simulated metrics worker panic")),
        )]);

        assert_eq!(reports.len(), 1);
        assert_eq!(reports[0].canister_id, entry.pid);
        assert_eq!(reports[0].status, MetricsCanisterStatus::Error);
        assert_eq!(reports[0].error.as_deref(), Some(METRICS_WORKER_PANIC));
    }

    #[test]
    fn metrics_response_failure_preserves_typed_cause_until_projection() {
        let error = MetricsQueryError::Response(IcpJsonResponseError::MissingResponseBytes);
        let source = std::error::Error::source(&error).expect("typed response source");

        assert!(matches!(
            source.downcast_ref::<IcpJsonResponseError>(),
            Some(IcpJsonResponseError::MissingResponseBytes)
        ));
    }
}