feat: adding ability to omit attributes for traces and metrics

.changesets/feat_allow_attribute_configuration_alocay.md

@@ -0,0 +1,70 @@
+### feat: adding ability to omit attributes for traces and metrics - @alocay PR #358
+
+Adding ability to configure which attributes are omitted from telemetry traces and metrics.
+
+1. Using a Rust build script (`build.rs`) to auto-generate telemetry attribute code based on the data found in `telemetry.toml`.
+2. Utilizing an enum for attributes so typos in the config file raise an error.
+3. Omitting trace attributes by filtering it out in a custom exporter.
+4. Omitting metric attributes by indicating which attributes are allowed via a view.
+5. Created `telemetry_attributes.rs` to map `TelemetryAttribute` enum to a OTEL `Key`.
+
+The `telemetry.toml` file includes attributes (both for metrics and traces) as well as list of metrics gathered. An example would look like the following:
+```
+[attributes.apollo.mcp]
+my_attribute = "Some attribute info"
+
+[metrics.apollo.mcp]
+some.count = "Some metric count info"
+```
+This would generate a file that looks like the following:
+```
+/// All TelemetryAttribute values
+pub const ALL_ATTRS: &[TelemetryAttribute; 1usize] = &[
+    TelemetryAttribute::MyAttribute
+];
+#[derive(Debug, ::serde::Deserialize, ::schemars::JsonSchema,, Clone, Eq, PartialEq, Hash, Copy)]
+pub enum TelemetryAttribute {
+    ///Some attribute info
+    #[serde(alias = "my_attribute")]
+    MyAttribute,
+}
+impl TelemetryAttribute {
+    /// Supported telemetry attribute (tags) values
+    pub const fn as_str(&self) -> &'static str {
+        match self {
+            TelemetryAttribute::MyAttribute => "apollo.mcp.my_attribute",
+        }
+    }
+}
+#[derive(Debug, ::serde::Deserialize, ::schemars::JsonSchema,, Clone, Eq, PartialEq, Hash, Copy)]
+pub enum TelemetryMetric {
+    ///Some metric count info
+    #[serde(alias = "some.count")]
+    SomeCount,
+}
+impl TelemetryMetric {
+    /// Converts TelemetryMetric to &str
+    pub const fn as_str(&self) -> &'static str {
+        match self {
+            TelemetryMetric::SomeCount => "apollo.mcp.some.count",
+        }
+    }
+}
+```
+An example configuration that omits `tool_name` attribute for metrics and `request_id` for tracing would look like the following:
+```
+telemetry:
+  exporters:
+    metrics:
+      otlp:
+        endpoint: "http://localhost:4317"
+        protocol: "grpc"
+      omitted_attributes:
+        - tool_name
+    tracing:
+      otlp:
+        endpoint: "http://localhost:4317"
+        protocol: "grpc"
+      omitted_attributes:
+        - request_id
+```

crates/apollo-mcp-server/Cargo.toml

@@ -6,6 +6,7 @@ license-file.workspace = true
 repository.workspace = true
 rust-version.workspace = true
 version.workspace = true
+build = "build.rs"
 
 default-run = "apollo-mcp-server"
 
@@ -41,7 +42,7 @@ opentelemetry-otlp = { version = "0.30.0", features = [
 opentelemetry-resource-detectors = "0.9.0"
 opentelemetry-semantic-conventions = "0.30.0"
 opentelemetry-stdout = "0.30.0"
-opentelemetry_sdk = "0.30.0"
+opentelemetry_sdk = { version = "0.30.0", features = ["spec_unstable_metrics_views"] }
 regex = "1.11.1"
 reqwest-middleware = "0.4.2"
 reqwest-tracing = { version = "0.5.8", features = ["opentelemetry_0_30"] }
@@ -65,6 +66,7 @@ tracing-opentelemetry = "0.31.0"
 tracing-subscriber = { version = "0.3.19", features = ["env-filter"] }
 tracing.workspace = true
 url.workspace = true
+async-trait = "0.1.89"
 
 [dev-dependencies]
 chrono = { version = "0.4.41", default-features = false, features = ["now"] }
@@ -76,6 +78,14 @@ rstest.workspace = true
 tokio.workspace = true
 tracing-test = "0.2.5"
 
+[build-dependencies]
+cruet = "0.15.0"
+prettyplease = "0.2.37"
+quote = "1.0.40"
+serde.workspace = true
+syn = "2.0.106"
+toml = "0.9.5"
+
 [lints]
 workspace = true