Resource.get modified to only need a reference (#2552)

Author: cijothomas

opentelemetry-sdk/CHANGELOG.md

@@ -269,6 +269,8 @@ re-introduced in a future date, along with the ability to change the cardinality
 limit.
 
 - *Breaking* Removed unused `opentelemetry_sdk::Error` enum.
+- *Breaking* Resource.get() modified to require reference to Key instead of owned.
+  Replace `get(Key::from_static_str("key"))` with `get(&Key::from_static_str("key"))`
 - *Breaking* (Affects custom Exporter authors only) Moved `ExportError` trait from `opentelemetry::export::ExportError` to `opentelemetry_sdk::ExportError`
 - *Breaking (Affects custom SpanExporter, SpanProcessor authors only)*: Rename namespaces for Span exporter structs/traits
   before:

opentelemetry-sdk/src/logs/log_emitter.rs

@@ -403,22 +403,22 @@ mod tests {
             assert_eq!(
                 provider
                     .resource()
-                    .get(Key::from_static_str(resource_key))
+                    .get(&Key::from_static_str(resource_key))
                     .map(|v| v.to_string()),
                 expect.map(|s| s.to_string())
             );
         };
         let assert_telemetry_resource = |provider: &super::LoggerProvider| {
             assert_eq!(
-                provider.resource().get(TELEMETRY_SDK_LANGUAGE.into()),
+                provider.resource().get(&TELEMETRY_SDK_LANGUAGE.into()),
                 Some(Value::from("rust"))
             );
             assert_eq!(
-                provider.resource().get(TELEMETRY_SDK_NAME.into()),
+                provider.resource().get(&TELEMETRY_SDK_NAME.into()),
                 Some(Value::from("opentelemetry"))
             );
             assert_eq!(
-                provider.resource().get(TELEMETRY_SDK_VERSION.into()),
+                provider.resource().get(&TELEMETRY_SDK_VERSION.into()),
                 Some(Value::from(env!("CARGO_PKG_VERSION")))
             );
         };

opentelemetry-sdk/src/metrics/meter_provider.rs

@@ -319,7 +319,7 @@ mod tests {
             assert_eq!(
                 provider.inner.pipes.0[0]
                     .resource
-                    .get(Key::from_static_str(resource_key))
+                    .get(&Key::from_static_str(resource_key))
                     .map(|v| v.to_string()),
                 expect.map(|s| s.to_string())
             );
@@ -328,19 +328,19 @@ mod tests {
             assert_eq!(
                 provider.inner.pipes.0[0]
                     .resource
-                    .get(TELEMETRY_SDK_LANGUAGE.into()),
+                    .get(&TELEMETRY_SDK_LANGUAGE.into()),
                 Some(Value::from("rust"))
             );
             assert_eq!(
                 provider.inner.pipes.0[0]
                     .resource
-                    .get(TELEMETRY_SDK_NAME.into()),
+                    .get(&TELEMETRY_SDK_NAME.into()),
                 Some(Value::from("opentelemetry"))
             );
             assert_eq!(
                 provider.inner.pipes.0[0]
                     .resource
-                    .get(TELEMETRY_SDK_VERSION.into()),
+                    .get(&TELEMETRY_SDK_VERSION.into()),
                 Some(Value::from(env!("CARGO_PKG_VERSION")))
             );
         };

opentelemetry-sdk/src/resource/env.rs

@@ -84,7 +84,7 @@ impl ResourceDetector for SdkProvidedResourceDetector {
                     .or_else(|| {
                         EnvResourceDetector::new()
                             .detect()
-                            .get(Key::new(super::SERVICE_NAME))
+                            .get(&Key::new(super::SERVICE_NAME))
                     })
                     .unwrap_or_else(|| "unknown_service".into()),
             )])
@@ -138,14 +138,14 @@ mod tests {
         // Ensure no env var set
         let no_env = SdkProvidedResourceDetector.detect();
         assert_eq!(
-            no_env.get(Key::from_static_str(crate::resource::SERVICE_NAME)),
+            no_env.get(&Key::from_static_str(crate::resource::SERVICE_NAME)),
             Some(Value::from("unknown_service")),
         );
 
         temp_env::with_var(OTEL_SERVICE_NAME, Some("test service"), || {
             let with_service = SdkProvidedResourceDetector.detect();
             assert_eq!(
-                with_service.get(Key::from_static_str(crate::resource::SERVICE_NAME)),
+                with_service.get(&Key::from_static_str(crate::resource::SERVICE_NAME)),
                 Some(Value::from("test service")),
             )
         });
@@ -156,7 +156,7 @@ mod tests {
             || {
                 let with_service = SdkProvidedResourceDetector.detect();
                 assert_eq!(
-                    with_service.get(Key::from_static_str(crate::resource::SERVICE_NAME)),
+                    with_service.get(&Key::from_static_str(crate::resource::SERVICE_NAME)),
                     Some(Value::from("test service1")),
                 )
             },
@@ -171,7 +171,7 @@ mod tests {
             || {
                 let with_service = SdkProvidedResourceDetector.detect();
                 assert_eq!(
-                    with_service.get(Key::from_static_str(crate::resource::SERVICE_NAME)),
+                    with_service.get(&Key::from_static_str(crate::resource::SERVICE_NAME)),
                     Some(Value::from("test service"))
                 );
             },

opentelemetry-sdk/src/resource/mod.rs

@@ -54,10 +54,11 @@ pub struct Resource {
 impl Resource {
     /// Creates a [ResourceBuilder] that allows you to configure multiple aspects of the Resource.
     ///
-    /// This [ResourceBuilder] will always include the following [ResourceDetector]s:
+    /// This [ResourceBuilder] will include the following [ResourceDetector]s:
     /// - [SdkProvidedResourceDetector]
     /// - [TelemetryResourceDetector]
     /// - [EnvResourceDetector]
+    ///   If you'd like to start from an empty resource, use [Resource::builder_empty].
     pub fn builder() -> ResourceBuilder {
         ResourceBuilder {
             resource: Self::from_detectors(&[
@@ -138,8 +139,6 @@ impl Resource {
     }
 
     /// Create a new `Resource` from resource detectors.
-    ///
-    /// timeout will be applied to each detector.
     fn from_detectors(detectors: &[Box<dyn ResourceDetector>]) -> Self {
         let mut resource = Resource::empty();
         for detector in detectors {
@@ -227,8 +226,8 @@ impl Resource {
     }
 
     /// Retrieve the value from resource associate with given key.
-    pub fn get(&self, key: Key) -> Option<Value> {
-        self.inner.attrs.get(&key).cloned()
+    pub fn get(&self, key: &Key) -> Option<Value> {
+        self.inner.attrs.get(key).cloned()
     }
 }
 
@@ -260,8 +259,6 @@ impl<'a> IntoIterator for &'a Resource {
 pub trait ResourceDetector {
     /// detect returns an initialized Resource based on gathered information.
     ///
-    /// timeout is used in case the detection operation takes too much time.
-    ///
     /// If source information to construct a Resource is inaccessible, an empty Resource should be returned
     ///
     /// If source information to construct a Resource is invalid, for example,

opentelemetry-sdk/src/trace/provider.rs

@@ -552,7 +552,7 @@ mod tests {
                 provider
                     .config()
                     .resource
-                    .get(Key::from_static_str(resource_key))
+                    .get(&Key::from_static_str(resource_key))
                     .map(|v| v.to_string()),
                 expect.map(|s| s.to_string())
             );
@@ -562,15 +562,18 @@ mod tests {
                 provider
                     .config()
                     .resource
-                    .get(TELEMETRY_SDK_LANGUAGE.into()),
+                    .get(&TELEMETRY_SDK_LANGUAGE.into()),
                 Some(Value::from("rust"))
             );
             assert_eq!(
-                provider.config().resource.get(TELEMETRY_SDK_NAME.into()),
+                provider.config().resource.get(&TELEMETRY_SDK_NAME.into()),
                 Some(Value::from("opentelemetry"))
             );
             assert_eq!(
-                provider.config().resource.get(TELEMETRY_SDK_VERSION.into()),
+                provider
+                    .config()
+                    .resource
+                    .get(&TELEMETRY_SDK_VERSION.into()),
                 Some(Value::from(env!("CARGO_PKG_VERSION")))
             );
         };

opentelemetry-sdk/src/trace/span_processor.rs

@@ -1222,7 +1222,7 @@ mod tests {
             exported_resource
                 .as_ref()
                 .unwrap()
-                .get(Key::new("service.name")),
+                .get(&Key::new("service.name")),
             Some(Value::from("test_service"))
         );
     }

opentelemetry-zipkin/src/exporter/mod.rs

@@ -116,7 +116,7 @@ impl ZipkinPipelineBuilder {
         } else {
             let service_name = SdkProvidedResourceDetector
                 .detect()
-                .get(semcov::resource::SERVICE_NAME.into())
+                .get(&semcov::resource::SERVICE_NAME.into())
                 .unwrap()
                 .to_string();
             (