feat(profiling): emit an otel protobuf

Author: danielsn

libdd-profiling/src/internal/location.rs

@@ -16,6 +16,17 @@ pub struct Location {
     pub line: i64,
 }
 
+impl Default for Location {
+    fn default() -> Self {
+        Self {
+            mapping_id: None,
+            function_id: super::FunctionId::from_offset(0),
+            address: 0,
+            line: 0,
+        }
+    }
+}
+
 impl Item for Location {
     type Id = LocationId;
 }

libdd-profiling/src/internal/mapping.rs

@@ -6,7 +6,7 @@ use super::*;
 /// Represents a [pprof::Mapping] with some space-saving changes:
 ///  - The id is not stored on the struct. It's stored in the container that holds the struct.
 ///  - ids for linked objects use 32-bit numbers instead of 64 bit ones.
-#[derive(Eq, PartialEq, Hash)]
+#[derive(Default, Eq, PartialEq, Hash)]
 pub struct Mapping {
     /// Address at which the binary (or DLL) is loaded into memory.
     pub memory_start: u64,

libdd-profiling/src/internal/mod.rs

@@ -7,7 +7,9 @@ mod function;
 mod label;
 mod location;
 mod mapping;
+#[cfg(not(feature = "otel"))]
 mod observation;
+#[cfg(feature = "otel")]
 mod otel_style_observation;
 mod profile;
 mod sample;
@@ -22,6 +24,9 @@ pub use label::*;
 pub use libdd_profiling_protobuf::ValueType;
 pub use location::*;
 pub use mapping::*;
+#[cfg(not(feature = "otel"))]
+pub use observation::*;
+#[cfg(feature = "otel")]
 pub use otel_style_observation::*;
 pub use profile::*;
 pub use sample::*;

libdd-profiling/src/internal/otel_style_observation.rs

@@ -10,8 +10,8 @@ use std::collections::{HashMap, HashSet};
 #[derive(Default)]
 pub struct Observations {
     sample_types: Box<[SampleType]>,
-    aggregated: HashMap<SampleType, HashMap<Sample, i64>>,
-    timestamped: HashMap<SampleType, HashMap<Sample, Vec<(i64, Timestamp)>>>,
+    pub aggregated: HashMap<SampleType, HashMap<Sample, i64>>,
+    pub timestamped: HashMap<SampleType, HashMap<Sample, Vec<(i64, Timestamp)>>>,
 }
 
 impl Observations {
@@ -64,15 +64,15 @@ impl Observations {
         let samples: HashSet<&Sample> = self
             .aggregated
             .iter()
-            .flat_map(|(_, samples)| samples.iter().map(|(s, _)| s))
+            .flat_map(|(_, samples)| samples.keys())
             .collect();
         samples.len()
     }
 
     pub fn timestamped_samples_count(&self) -> usize {
         self.timestamped
             .iter()
-            .flat_map(|(_, v)| v.iter().map(|(_, v)| v.len()))
+            .flat_map(|(_, v)| v.values().map(|v| v.len()))
             .sum()
     }
 
@@ -82,6 +82,8 @@ impl Observations {
         Ok(self.into_iter())
     }
 
+    // TODO make this a trait impl
+    #[allow(clippy::should_implement_trait)]
     pub fn into_iter(self) -> impl Iterator<Item = (Sample, Option<Timestamp>, Vec<i64>)> {
         let index_map: HashMap<SampleType, usize> = self
             .sample_types