sampler_config/runtime/

mod.rs

// Copyright 2025 The Fuchsia Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

use crate::common::{CustomerId, EventCode, MetricId, MetricType, ProjectId};
use fidl_fuchsia_diagnostics::Selector;
use selectors::SelectorDisplayOptions;
use serde::ser::{Error, SerializeSeq};
use serde::{Deserialize, Serialize, Serializer};

/// Configuration for a single project to map Inspect data to its Cobalt metrics.
#[derive(Serialize, Deserialize, Debug, PartialEq)]
pub struct ProjectConfig {
    /// Project ID that metrics are being sampled and forwarded on behalf of.
    pub project_id: ProjectId,

    /// Customer ID that metrics are being sampled and forwarded on behalf of.
    /// This will default to 1 if not specified.
    #[serde(default)]
    pub customer_id: CustomerId,

    /// The frequency with which metrics are sampled, in seconds.
    #[serde(deserialize_with = "crate::utils::greater_than_zero")]
    pub poll_rate_sec: i64,

    /// The collection of mappings from Inspect to Cobalt.
    pub metrics: Vec<MetricConfig>,
}

/// Configuration for a single metric to map from an Inspect property to a Cobalt metric.
#[derive(Clone, Serialize, Deserialize, Debug, PartialEq)]
pub struct MetricConfig {
    /// Selector identifying the metric to sample via the diagnostics platform.
    #[serde(
        rename = "selector",
        deserialize_with = "crate::utils::one_or_many_selectors",
        serialize_with = "selectors_to_string"
    )]
    pub selectors: Vec<Selector>,

    /// Cobalt metric id to map the selector to.
    pub metric_id: MetricId,

    /// Data type to transform the metric to.
    pub metric_type: MetricType,

    /// Event codes defining the dimensions of the Cobalt metric. Note: Order matters, and must
    /// match the order of the defined dimensions in the Cobalt metric file.
    /// Missing field means the same as empty list.
    #[serde(default)]
    pub event_codes: Vec<EventCode>,

    /// Optional boolean specifying whether to upload the specified metric only once, the first time
    /// it becomes available to the sampler. Defaults to false.
    #[serde(default)]
    pub upload_once: bool,

    /// Optional project id. When present this project id will be used instead of the top-level
    /// project id.
    // TODO(https://fxbug.dev/42071858): remove this when we support batching.
    pub project_id: Option<ProjectId>,
}

pub fn selectors_to_string<S>(selectors: &[Selector], serializer: S) -> Result<S::Ok, S::Error>
where
    S: Serializer,
{
    let mut seq = serializer.serialize_seq(Some(selectors.len()))?;
    for selector in selectors {
        let selector_string =
            selectors::selector_to_string(selector, SelectorDisplayOptions::never_wrap_in_quotes())
                .map_err(S::Error::custom)?;
        seq.serialize_element(&selector_string)?;
    }
    seq.end()
}

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

    #[fuchsia::test]
    fn parse_valid_sampler_config() {
        let ok_json = r#"{
            "project_id": 5,
            "poll_rate_sec": 60,
            "metrics": [
              {
                "selector": "bootstrap/archivist:root/all_archive_accessor:inspect_batch_iterator_get_next_requests",
                "metric_id": 1,
                "metric_type": "Occurrence",
                "event_codes": [0, 0]
              }
            ]
        }"#;

        let config: ProjectConfig = serde_json5::from_str(ok_json).expect("parse json");
        assert_eq!(config, ProjectConfig {
            project_id: ProjectId(5),
            poll_rate_sec: 60,
            customer_id: CustomerId(1),
            metrics: vec![
                MetricConfig {
                    selectors: vec![
                        selectors::parse_verbose("bootstrap/archivist:root/all_archive_accessor:inspect_batch_iterator_get_next_requests").unwrap(),
                    ],
                    metric_id: MetricId(1),
                    metric_type: MetricType::Occurrence,
                    event_codes: vec![EventCode(0), EventCode(0)],
                    project_id: None,
                    upload_once: false,
                }
            ]
        });
    }

    #[fuchsia::test]
    fn parse_valid_sampler_config_json5() {
        let ok_json = r#"{
          project_id: 5,
          poll_rate_sec: 3,
          metrics: [
            {
              // Test comment for json5 portability.
              selector: "single_counter_test_component:root:counter",
              metric_id: 1,
              metric_type: "Occurrence",
              event_codes: [0, 0]
            }
          ]
        }"#;

        let config: ProjectConfig = serde_json5::from_str(ok_json).expect("parse json");
        assert_eq!(
            config,
            ProjectConfig {
                project_id: ProjectId(5),
                poll_rate_sec: 3,
                customer_id: CustomerId(1),
                metrics: vec![MetricConfig {
                    selectors: vec![selectors::parse_verbose(
                        "single_counter_test_component:root:counter"
                    )
                    .unwrap(),],
                    metric_id: MetricId(1),
                    metric_type: MetricType::Occurrence,
                    upload_once: false,
                    event_codes: vec![EventCode(0), EventCode(0)],
                    project_id: None,
                }]
            }
        );
    }

    #[fuchsia::test]
    fn parse_invalid_config() {
        let invalid_json = r#"{
          "project_id": 5,
          "poll_rate_sec": 3,
          "invalid_field": "bad bad bad"
        }"#;

        serde_json5::from_str::<ProjectConfig>(invalid_json)
            .expect_err("fail to load invalid config");
    }

    #[fuchsia::test]
    fn parse_optional_args() {
        let true_json = r#"{
           "project_id": 5,
           "poll_rate_sec": 60,
           "metrics": [
             {
               // Test comment for json5 portability.
               "selector": "bootstrap/archivist:root/all_archive_accessor:inspect_batch_iterator_get_next_requests",
               "metric_id": 1,
               "metric_type": "Occurrence",
               "event_codes": [0, 0],
               "upload_once": true,
             }
           ]
         }"#;

        let config: ProjectConfig = serde_json5::from_str(true_json).expect("parse json");
        assert_eq!(
            config,
            ProjectConfig {
                project_id: ProjectId(5),
                poll_rate_sec: 60,
                customer_id: CustomerId(1),
                metrics: vec![MetricConfig {
                    selectors: vec![
                        selectors::parse_verbose("bootstrap/archivist:root/all_archive_accessor:inspect_batch_iterator_get_next_requests").unwrap(),
                    ],
                    metric_id: MetricId(1),
                    metric_type: MetricType::Occurrence,
                    upload_once: true,
                    event_codes: vec![EventCode(0), EventCode(0)],
                    project_id: None,
                }]
            }
        );

        let false_json = r#"{
          "project_id": 5,
          "poll_rate_sec": 60,
          "metrics": [
            {
              // Test comment for json5 portability.
              "selector": "bootstrap/archivist:root/all_archive_accessor:inspect_batch_iterator_get_next_requests",
              "metric_id": 1,
              "metric_type": "Occurrence",
              "event_codes": [0, 0],
              "upload_once": false,
            }
          ]
        }"#;
        let config: ProjectConfig = serde_json5::from_str(false_json).expect("parse json");
        assert_eq!(
            config,
            ProjectConfig {
                project_id: ProjectId(5),
                poll_rate_sec: 60,
                customer_id: CustomerId(1),
                metrics: vec![MetricConfig {
                    selectors: vec![
                        selectors::parse_verbose("bootstrap/archivist:root/all_archive_accessor:inspect_batch_iterator_get_next_requests").unwrap(),
                    ],
                    metric_id: MetricId(1),
                    metric_type: MetricType::Occurrence,
                    upload_once: false,
                    event_codes: vec![EventCode(0), EventCode(0)],
                    project_id: None
                }]
            }
        );
    }
    #[fuchsia::test]
    fn default_customer_id() {
        let default_json = r#"{
          "project_id": 5,
          "poll_rate_sec": 60,
          "metrics": [
            {
              "selector": "bootstrap/archivist:root/all_archive_accessor:inspect_batch_iterator_get_next_requests",
              "metric_id": 1,
              "metric_type": "Occurrence",
              "event_codes": [0, 0]
            }
          ]
        }"#;
        let with_customer_id_json = r#"{
            "customer_id": 6,
            "project_id": 5,
            "poll_rate_sec": 3,
            "metrics": [
              {
                "selector": "single_counter_test_component:root:counter",
                "metric_id": 1,
                "metric_type": "Occurrence",
                "event_codes": [0, 0]
              }
            ]
          }
          "#;

        let config: ProjectConfig = serde_json5::from_str(default_json).expect("deserialize");
        assert_eq!(
            config,
            ProjectConfig {
                project_id: ProjectId(5),
                poll_rate_sec: 60,
                customer_id: CustomerId(1),
                metrics: vec![MetricConfig {
                    selectors: vec![
                        selectors::parse_verbose("bootstrap/archivist:root/all_archive_accessor:inspect_batch_iterator_get_next_requests").unwrap(),
                    ],
                    metric_id: MetricId(1),
                    metric_type: MetricType::Occurrence,
                    upload_once: false,
                    event_codes: vec![EventCode(0), EventCode(0)],
                    project_id: None,
                }],
            }
        );

        let config: ProjectConfig =
            serde_json5::from_str(with_customer_id_json).expect("deserialize");
        assert_eq!(
            config,
            ProjectConfig {
                project_id: ProjectId(5),
                poll_rate_sec: 3,
                customer_id: CustomerId(6),
                metrics: vec![MetricConfig {
                    selectors: vec![selectors::parse_verbose(
                        "single_counter_test_component:root:counter"
                    )
                    .unwrap(),],
                    metric_id: MetricId(1),
                    metric_type: MetricType::Occurrence,
                    upload_once: false,
                    event_codes: vec![EventCode(0), EventCode(0)],
                    project_id: None,
                }]
            }
        );
    }

    #[fuchsia::test]
    fn missing_event_codes_ok() {
        let default_json = r#"{
          "project_id": 5,
          "poll_rate_sec": 60,
          "metrics": [
            {
              "selector": "bootstrap/archivist:root/all_archive_accessor:inspect_batch_iterator_get_next_requests",
              "metric_id": 1,
              "metric_type": "Occurrence",
            }
          ]
        }"#;

        let config: ProjectConfig = serde_json5::from_str(default_json).expect("deserialize");
        assert_eq!(
            config,
            ProjectConfig {
                project_id: ProjectId(5),
                poll_rate_sec: 60,
                customer_id: CustomerId(1),
                metrics: vec![MetricConfig {
                    selectors: vec![
                        selectors::parse_verbose("bootstrap/archivist:root/all_archive_accessor:inspect_batch_iterator_get_next_requests").unwrap(),
                    ],
                    metric_id: MetricId(1),
                    metric_type: MetricType::Occurrence,
                    upload_once: false,
                    event_codes: vec![],
                    project_id: None,
                }]
            }
        );
    }
}