address review comments

Author: ramgdev

opentelemetry-otlp/Cargo.toml

@@ -31,7 +31,7 @@ futures-core = { workspace = true }
 opentelemetry = { version = "0.22", default-features = false, path = "../opentelemetry" }
 opentelemetry_sdk = { version = "0.22", default-features = false, path = "../opentelemetry-sdk" }
 opentelemetry-http = { version = "0.11", path = "../opentelemetry-http", optional = true }
-opentelemetry-proto = { version = "0.5", path = "../opentelemetry-proto", default-features = false,  features=["with-serde"] }
+opentelemetry-proto = { version = "0.5", path = "../opentelemetry-proto", default-features = false }
 opentelemetry-semantic-conventions = { version = "0.14", path = "../opentelemetry-semantic-conventions" }
 
 prost = { workspace = true, optional = true }
@@ -75,7 +75,7 @@ reqwest-blocking-client = ["reqwest/blocking", "opentelemetry-http/reqwest"]
 reqwest-client = ["reqwest", "opentelemetry-http/reqwest"]
 reqwest-rustls = ["reqwest", "reqwest/rustls-tls-native-roots"]
 # http json
-http-json = ["serde_json", "prost", "opentelemetry-http", "opentelemetry-proto/gen-tonic-messages", "http", "trace", "metrics"]
+http-json = ["serde_json", "prost", "opentelemetry-http", "opentelemetry-proto/gen-tonic-messages", "opentelemetry-proto/with-serde", "http", "trace", "metrics"]
 
 # test
 integration-testing = ["tonic", "prost", "tokio/full", "trace"]

opentelemetry-otlp/src/exporter/http/trace.rs

@@ -71,22 +71,26 @@ impl SpanExporter for OtlpHttpClient {
 #[cfg(any(feature = "http-proto", feature = "http-json"))]
 fn build_body(spans: Vec<SpanData>) -> TraceResult<(Vec<u8>, &'static str)> {
     use opentelemetry_proto::tonic::collector::trace::v1::ExportTraceServiceRequest;
+    use prost::Message;
+
+    use crate::{exporter::default_protocol, Protocol};
 
     let req = ExportTraceServiceRequest {
         resource_spans: spans.into_iter().map(Into::into).collect(),
     };
     let buf;
     let ctype;
-    #[cfg(all(feature = "http-proto", not(feature = "http-json")))]{
-        use prost::Message;
-        buf = req.encode_to_vec();
-        ctype = "application/x-protobuf";
-    }
-    #[cfg(all(feature = "http-json", not(feature = "http-proto")))]{
-        let json_struct = serde_json::to_string_pretty(&req).unwrap();
-        buf = json_struct.into();
-        ctype = "application/json";
-    }
+    match default_protocol() {
+        Protocol::HttpJson => {
+            let json_struct = serde_json::to_string_pretty(&req).unwrap();
+            buf = json_struct.into();
+            ctype = "application/json";    
+        },
+        _ => {
+            buf = req.encode_to_vec();
+            ctype = "application/x-protobuf";    
+        },
+    };
     Ok((buf, ctype))
 }