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Diffstat (limited to 'toolkit/components/glean/api/src/private/counter.rs')
| -rw-r--r-- | toolkit/components/glean/api/src/private/counter.rs | 182 |
1 files changed, 182 insertions, 0 deletions
diff --git a/toolkit/components/glean/api/src/private/counter.rs b/toolkit/components/glean/api/src/private/counter.rs new file mode 100644 index 0000000000..7e1498f70f --- /dev/null +++ b/toolkit/components/glean/api/src/private/counter.rs @@ -0,0 +1,182 @@ +// This Source Code Form is subject to the terms of the Mozilla Public +// License, v. 2.0. If a copy of the MPL was not distributed with this +// file, You can obtain one at https://mozilla.org/MPL/2.0/. + +use inherent::inherent; +use std::sync::Arc; + +use glean::traits::Counter; + +use super::{CommonMetricData, MetricId}; +use crate::ipc::{need_ipc, with_ipc_payload}; + +/// A counter metric. +/// +/// Used to count things. +/// The value can only be incremented, not decremented. +#[derive(Clone)] +pub enum CounterMetric { + Parent { + /// The metric's ID. + /// + /// **TEST-ONLY** - Do not use unless gated with `#[cfg(test)]`. + id: MetricId, + inner: Arc<glean::private::CounterMetric>, + }, + Child(CounterMetricIpc), +} +#[derive(Clone, Debug)] +pub struct CounterMetricIpc(MetricId); + +impl CounterMetric { + /// Create a new counter metric. + pub fn new(id: MetricId, meta: CommonMetricData) -> Self { + if need_ipc() { + CounterMetric::Child(CounterMetricIpc(id)) + } else { + let inner = Arc::new(glean::private::CounterMetric::new(meta)); + CounterMetric::Parent { id, inner } + } + } + + #[cfg(test)] + pub(crate) fn metric_id(&self) -> MetricId { + match self { + CounterMetric::Parent { id, .. } => *id, + CounterMetric::Child(c) => c.0, + } + } + + #[cfg(test)] + pub(crate) fn child_metric(&self) -> Self { + match self { + CounterMetric::Parent { id, .. } => CounterMetric::Child(CounterMetricIpc(*id)), + CounterMetric::Child(_) => panic!("Can't get a child metric from a child metric"), + } + } +} + +#[inherent] +impl Counter for CounterMetric { + /// Increase the counter by `amount`. + /// + /// ## Arguments + /// + /// * `amount` - The amount to increase by. Should be positive. + /// + /// ## Notes + /// + /// Logs an error if the `amount` is 0 or negative. + pub fn add(&self, amount: i32) { + match self { + CounterMetric::Parent { inner, .. } => { + inner.add(amount); + } + CounterMetric::Child(c) => { + with_ipc_payload(move |payload| { + if let Some(v) = payload.counters.get_mut(&c.0) { + *v += amount; + } else { + payload.counters.insert(c.0, amount); + } + }); + } + } + } + + /// **Test-only API.** + /// + /// Get the currently stored value as an integer. + /// This doesn't clear the stored value. + /// + /// ## Arguments + /// + /// * `ping_name` - the storage name to look into. + /// + /// ## Return value + /// + /// Returns the stored value or `None` if nothing stored. + pub fn test_get_value<'a, S: Into<Option<&'a str>>>(&self, ping_name: S) -> Option<i32> { + let ping_name = ping_name.into().map(|s| s.to_string()); + match self { + CounterMetric::Parent { inner, .. } => inner.test_get_value(ping_name), + CounterMetric::Child(c) => { + panic!("Cannot get test value for {:?} in non-parent process!", c.0) + } + } + } + + /// **Test-only API.** + /// + /// Gets the number of recorded errors for the given metric and error type. + /// + /// # Arguments + /// + /// * `error` - The type of error + /// * `ping_name` - represents the optional name of the ping to retrieve the + /// metric for. Defaults to the first value in `send_in_pings`. + /// + /// # Returns + /// + /// The number of errors reported. + pub fn test_get_num_recorded_errors(&self, error: glean::ErrorType) -> i32 { + match self { + CounterMetric::Parent { inner, .. } => inner.test_get_num_recorded_errors(error), + CounterMetric::Child(c) => panic!( + "Cannot get the number of recorded errors for {:?} in non-parent process!", + c.0 + ), + } + } +} + +#[cfg(test)] +mod test { + use crate::{common_test::*, ipc, metrics}; + + #[test] + fn sets_counter_value_parent() { + let _lock = lock_test(); + + let metric = &metrics::test_only_ipc::a_counter; + metric.add(1); + + assert_eq!(1, metric.test_get_value("store1").unwrap()); + } + + #[test] + fn sets_counter_value_child() { + let _lock = lock_test(); + + let parent_metric = &metrics::test_only_ipc::a_counter; + parent_metric.add(3); + + { + let child_metric = parent_metric.child_metric(); + + // scope for need_ipc RAII + let _raii = ipc::test_set_need_ipc(true); + let metric_id = child_metric.metric_id(); + + child_metric.add(42); + + ipc::with_ipc_payload(move |payload| { + assert!( + 42 == *payload.counters.get(&metric_id).unwrap(), + "Stored the correct value in the ipc payload" + ); + }); + } + + assert!( + false == ipc::need_ipc(), + "RAII dropped, should not need ipc any more" + ); + assert!(ipc::replay_from_buf(&ipc::take_buf().unwrap()).is_ok()); + + assert!( + 45 == parent_metric.test_get_value("store1").unwrap(), + "Values from the 'processes' should be summed" + ); + } +} |