ref(metrics): Add custom and more builtin units [INGEST-939]

CHANGELOG.md

@@ -11,6 +11,7 @@
 - Remove unused item types. ([#1211](https://github.com/getsentry/relay/pull/1211))
 - Pin click dependency in requirements-dev.txt. ([#1214](https://github.com/getsentry/relay/pull/1214))
 - Use fully qualified metric resource identifiers (MRI) for metrics ingestion. For example, the sessions duration is now called `d:sessions/duration@s`. ([#1215](https://github.com/getsentry/relay/pull/1215))
+- Introduce metric units for rates and information, add support for custom user-declared units, and rename duration units to self-explanatory identifiers such as `second`. ([#1217](https://github.com/getsentry/relay/pull/1217))
 
 ## 22.3.0
 

relay-metrics/src/aggregation.rs

@@ -616,7 +616,7 @@ pub struct ParseBucketError(#[cause] serde_json::Error);
 ///     "timestamp": 1615889440,
 ///     "name": "endpoint.response_time",
 ///     "type": "d",
-///     "unit": "ms",
+///     "unit": "millisecond",
 ///     "value": [36, 49, 57, 68],
 ///     "tags": {
 ///       "route": "user_index"
@@ -1365,7 +1365,7 @@ mod tests {
 
     use super::*;
 
-    use crate::{DurationPrecision, MetricUnit};
+    use crate::{DurationUnit, MetricUnit};
 
     struct BucketCountInquiry;
 
@@ -1520,7 +1520,7 @@ mod tests {
         let json = r#"[
           {
             "name": "endpoint.response_time",
-            "unit": "ms",
+            "unit": "millisecond",
             "value": [36, 49, 57, 68],
             "type": "d",
             "timestamp": 1615889440,
@@ -1877,7 +1877,7 @@ mod tests {
         let metric1 = some_metric();
 
         let mut metric2 = metric1.clone();
-        metric2.unit = MetricUnit::Duration(DurationPrecision::Second);
+        metric2.unit = MetricUnit::Duration(DurationUnit::Second);
 
         // It's OK to have same metric with different units:
         aggregator.insert(project_key, metric1).unwrap();

relay-metrics/src/lib.rs

@@ -11,7 +11,7 @@
 //! looks like this:
 //!
 //! ```text
-//! endpoint.response_time@ms:57|d|#route:user_index
+//! endpoint.response_time@millisecond:57|d|#route:user_index
 //! endpoint.hits:1|c|#route:user_index
 //! ```
 //!
@@ -26,7 +26,7 @@
 //! ```text
 //! {}
 //! {"type": "metrics", "timestamp": 1615889440, ...}
-//! endpoint.response_time@ms:57|d|#route:user_index
+//! endpoint.response_time@millisecond:57|d|#route:user_index
 //! ...
 //! ```
 //!
@@ -48,7 +48,7 @@
 //! [
 //!   {
 //!     "name": "endpoint.response_time",
-//!     "unit": "ms",
+//!     "unit": "millisecond",
 //!     "value": [36, 49, 57, 68],
 //!     "type": "d",
 //!     "timestamp": 1615889440,
@@ -71,34 +71,22 @@
 //! # Ingestion
 //!
 //! Processing Relays write aggregate buckets into the ingestion Kafka stream. The schema is similar
-//! to the aggregation payload, with the addition of scoping information:
+//! to the aggregation payload, with the addition of scoping information. Each bucket is sent in a
+//! separate message:
 //!
 //! ```json
-//! [
-//!   {
-//!     "org_id": 1,
-//!     "project_id": 42,
-//!     "name": "endpoint.response_time",
-//!     "unit": "ms",
-//!     "value": [36, 49, 57, 68],
-//!     "type": "d",
-//!     "timestamp": 1615889440,
-//!     "tags": {
-//!       "route": "user_index"
-//!     }
-//!   },
-//!   {
-//!     "org_id": 1,
-//!     "project_id": 42,
-//!     "name": "endpoint.hits",
-//!     "value": 4,
-//!     "type": "c",
-//!     "timestamp": 1615889440,
-//!     "tags": {
-//!       "route": "user_index"
-//!     }
+//! {
+//!   "org_id": 1,
+//!   "project_id": 42,
+//!   "name": "endpoint.response_time",
+//!   "unit": "millisecond",
+//!   "value": [36, 49, 57, 68],
+//!   "type": "d",
+//!   "timestamp": 1615889440,
+//!   "tags": {
+//!     "route": "user_index"
 //!   }
-//! ]
+//! }
 //! ```
 #![warn(missing_docs)]
 #![doc(