Struct metrics_util::Registry [−][src]
pub struct Registry<K, H> where
K: Eq + Hashable + Clone + 'static,
H: 'static, { /* fields omitted */ }
A high-performance metric registry.
Registry
provides the ability to maintain a central listing of metrics mapped by a given key.
In many cases, K
will be a composite key, where the fundamental Key
type from metrics
is
present, and differentiation is provided by storing the metric type alongside.
Metrics themselves are represented opaquely behind H
. In most cases, this would be a
thread-safe handle to the underlying metrics storage that the owner of the registry can use to
update the actual metric value(s) as needed. Handle
, from this crate, is a solid default
choice.
As well, handles have an associated generation counter which is incremented any time an entry is operated on. This generation is returned with the handle when querying the registry, and can be used in order to delete a handle from the registry, allowing callers to prune old/stale handles over time.
Registry
is optimized for reads.
Implementations
impl<K, H> Registry<K, H> where
K: Eq + Hashable + Clone + 'static,
H: 'static,
[src]
impl<K, H> Registry<K, H> where
K: Eq + Hashable + Clone + 'static,
H: 'static,
[src]pub fn new() -> Self
[src]
Creates a new Registry
.
pub fn op<I, O, V>(&self, kind: MetricKind, key: &K, op: O, init: I) -> V where
I: FnOnce() -> H,
O: FnOnce(&H) -> V,
[src]
I: FnOnce() -> H,
O: FnOnce(&H) -> V,
Perform an operation on a given key.
The op
function will be called for the handle under the given key
.
If the key
is not already mapped, the init
function will be
called, and the resulting handle will be stored in the registry.
pub fn delete(&self, kind: MetricKind, key: &K, generation: Generation) -> bool
[src]
Deletes a handle from the registry.
The generation of a given key is passed along when querying the registry via
get_handles
. If the generation given here does not match the
current generation, then the handle will not be removed.
pub fn get_handles(&self) -> HashMap<(MetricKind, K), (Generation, H)> where
H: Clone,
[src]
H: Clone,
Gets a map of all present handles, mapped by key.
Handles must implement Clone
. This map is a point-in-time snapshot of the registry.
Trait Implementations
Auto Trait Implementations
impl<K, H> !RefUnwindSafe for Registry<K, H>
impl<K, H> !RefUnwindSafe for Registry<K, H>
impl<K, H> UnwindSafe for Registry<K, H> where
H: UnwindSafe,
K: UnwindSafe,
impl<K, H> UnwindSafe for Registry<K, H> where
H: UnwindSafe,
K: UnwindSafe,