From 1482d5ca6a9ec80aef265acd6c7dc66561456deb Mon Sep 17 00:00:00 2001
From: Ramajeyam Gopalraj <ramgdev@gmail.com>
Date: Mon, 26 Feb 2024 22:10:39 -0500
Subject: [PATCH 01/22] Add http-json feature flag

---
 opentelemetry-otlp/Cargo.toml                 |  5 +++-
 .../examples/basic-otlp-http/Cargo.toml       |  2 +-
 opentelemetry-otlp/src/exporter/http/mod.rs   |  2 +-
 opentelemetry-otlp/src/exporter/http/trace.rs |  8 +++---
 opentelemetry-otlp/src/exporter/mod.rs        | 28 +++++++++++--------
 opentelemetry-otlp/src/lib.rs                 | 23 +++++++--------
 opentelemetry-otlp/src/span.rs                |  8 +++---
 7 files changed, 43 insertions(+), 33 deletions(-)

diff --git a/opentelemetry-otlp/Cargo.toml b/opentelemetry-otlp/Cargo.toml
index 7224392543..70668cf2cd 100644
--- a/opentelemetry-otlp/Cargo.toml
+++ b/opentelemetry-otlp/Cargo.toml
@@ -42,6 +42,7 @@ reqwest = { workspace = true, optional = true }
 http = { workspace = true, optional = true }
 serde = { workspace = true, features = ["derive"], optional = true }
 thiserror = { workspace = true }
+serde_json = { workspace = true, optional = true }
 
 [dev-dependencies]
 tokio-stream = { workspace = true, features = ["net"] }
@@ -58,7 +59,7 @@ metrics = ["opentelemetry/metrics", "opentelemetry_sdk/metrics", "opentelemetry-
 logs = ["opentelemetry/logs", "opentelemetry_sdk/logs", "opentelemetry-proto/logs"]
 
 # add ons
-serialize = ["serde"]
+serialize = ["serde", "serde_json"]
 
 default = ["grpc-tonic", "trace"]
 
@@ -73,6 +74,8 @@ http-proto = ["prost", "opentelemetry-http", "opentelemetry-proto/gen-tonic-mess
 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"]
 
 # test
 integration-testing = ["tonic", "prost", "tokio/full", "trace"]
diff --git a/opentelemetry-otlp/examples/basic-otlp-http/Cargo.toml b/opentelemetry-otlp/examples/basic-otlp-http/Cargo.toml
index 496dfc70b1..4530074a79 100644
--- a/opentelemetry-otlp/examples/basic-otlp-http/Cargo.toml
+++ b/opentelemetry-otlp/examples/basic-otlp-http/Cargo.toml
@@ -9,7 +9,7 @@ publish = false
 once_cell = { workspace = true }
 opentelemetry = { path = "../../../opentelemetry" }
 opentelemetry_sdk = { path = "../../../opentelemetry-sdk", features = ["rt-tokio", "metrics", "logs"] }
-opentelemetry-otlp = { path = "../..", features = ["http-proto", "reqwest-client", "logs"] }
+opentelemetry-otlp = { path = "../..", features = ["http-proto", "http-json", "reqwest-client", "logs"] }
 opentelemetry-appender-tracing = { path = "../../../opentelemetry-appender-tracing", default-features = false}
 opentelemetry-semantic-conventions = { path = "../../../opentelemetry-semantic-conventions" }
 
diff --git a/opentelemetry-otlp/src/exporter/http/mod.rs b/opentelemetry-otlp/src/exporter/http/mod.rs
index 6cd90203a7..ef64662038 100644
--- a/opentelemetry-otlp/src/exporter/http/mod.rs
+++ b/opentelemetry-otlp/src/exporter/http/mod.rs
@@ -22,7 +22,7 @@ mod logs;
 mod trace;
 
 /// Configuration of the http transport
-#[cfg(feature = "http-proto")]
+#[cfg(any(feature = "http-proto", feature = "http-json"))]
 #[derive(Debug)]
 #[cfg_attr(
     all(
diff --git a/opentelemetry-otlp/src/exporter/http/trace.rs b/opentelemetry-otlp/src/exporter/http/trace.rs
index e824978b57..e9a8606c88 100644
--- a/opentelemetry-otlp/src/exporter/http/trace.rs
+++ b/opentelemetry-otlp/src/exporter/http/trace.rs
@@ -68,7 +68,7 @@ impl SpanExporter for OtlpHttpClient {
     }
 }
 
-#[cfg(feature = "http-proto")]
+#[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;
@@ -79,12 +79,12 @@ fn build_body(spans: Vec<SpanData>) -> TraceResult<(Vec<u8>, &'static str)> {
     let mut buf = vec![];
     req.encode(&mut buf).map_err(crate::Error::from)?;
 
-    Ok((buf, "application/x-protobuf"))
+    Ok((buf, "application/x-protobuf"))    
 }
 
-#[cfg(not(feature = "http-proto"))]
+#[cfg(not(any(feature = "http-proto", feature = "http-json")))]
 fn build_body(spans: Vec<SpanData>) -> TraceResult<(Vec<u8>, &'static str)> {
     Err(TraceError::Other(
-        "No http protocol configured. Enable one via `http-proto`".into(),
+        "No http protocol configured. Enable one via `http-proto` or `http-json`".into(),
     ))
 }
diff --git a/opentelemetry-otlp/src/exporter/mod.rs b/opentelemetry-otlp/src/exporter/mod.rs
index 668474d798..6403222446 100644
--- a/opentelemetry-otlp/src/exporter/mod.rs
+++ b/opentelemetry-otlp/src/exporter/mod.rs
@@ -2,7 +2,7 @@
 //!
 //! OTLP supports sending data via different protocols and formats.
 
-#[cfg(feature = "http-proto")]
+#[cfg(any(feature = "http-proto", feature = "http-json"))]
 use crate::exporter::http::HttpExporterBuilder;
 #[cfg(feature = "grpc-tonic")]
 use crate::exporter::tonic::TonicExporterBuilder;
@@ -31,15 +31,19 @@ pub const OTEL_EXPORTER_OTLP_COMPRESSION: &str = "OTEL_EXPORTER_OTLP_COMPRESSION
 #[cfg(feature = "http-proto")]
 /// Default protocol, using http-proto.
 pub const OTEL_EXPORTER_OTLP_PROTOCOL_DEFAULT: &str = OTEL_EXPORTER_OTLP_PROTOCOL_HTTP_PROTOBUF;
-#[cfg(all(feature = "grpc-tonic", not(feature = "http-proto")))]
-/// Default protocol, using grpc as http-proto feature is not enabled.
+#[cfg(all(feature = "http-json", feature = "trace", not(any(feature = "http-proto", feature = "grpc-tonic"))))]
+/// Default protocol, using http-json.
+pub const OTEL_EXPORTER_OTLP_PROTOCOL_DEFAULT: &str = OTEL_EXPORTER_OTLP_PROTOCOL_HTTP_JSON;
+#[cfg(all(feature = "grpc-tonic", not(any(feature = "http-proto", feature = "http-json"))))]
+/// Default protocol, using grpc as http-proto or http-json feature is not enabled.
 pub const OTEL_EXPORTER_OTLP_PROTOCOL_DEFAULT: &str = OTEL_EXPORTER_OTLP_PROTOCOL_GRPC;
-#[cfg(not(any(any(feature = "grpc-tonic", feature = "http-proto"))))]
+#[cfg(not(any(any(feature = "grpc-tonic", feature = "http-proto", feature = "http-json"))))]
 /// Default protocol if no features are enabled.
 pub const OTEL_EXPORTER_OTLP_PROTOCOL_DEFAULT: &str = "";
 
 const OTEL_EXPORTER_OTLP_PROTOCOL_HTTP_PROTOBUF: &str = "http/protobuf";
 const OTEL_EXPORTER_OTLP_PROTOCOL_GRPC: &str = "grpc";
+const OTEL_EXPORTER_OTLP_PROTOCOL_HTTP_JSON: &str = "http/json";
 
 /// Max waiting time for the backend to process each signal batch, defaults to 10 seconds.
 pub const OTEL_EXPORTER_OTLP_TIMEOUT: &str = "OTEL_EXPORTER_OTLP_TIMEOUT";
@@ -50,7 +54,7 @@ pub const OTEL_EXPORTER_OTLP_TIMEOUT_DEFAULT: u64 = 10;
 const OTEL_EXPORTER_OTLP_GRPC_ENDPOINT_DEFAULT: &str = "http://localhost:4317";
 const OTEL_EXPORTER_OTLP_HTTP_ENDPOINT_DEFAULT: &str = "http://localhost:4318";
 
-#[cfg(feature = "http-proto")]
+#[cfg(any(feature = "http-proto", feature = "http-json"))]
 pub(crate) mod http;
 #[cfg(feature = "grpc-tonic")]
 pub(crate) mod tonic;
@@ -112,6 +116,7 @@ fn default_protocol() -> Protocol {
     match OTEL_EXPORTER_OTLP_PROTOCOL_DEFAULT {
         OTEL_EXPORTER_OTLP_PROTOCOL_HTTP_PROTOBUF => Protocol::HttpBinary,
         OTEL_EXPORTER_OTLP_PROTOCOL_GRPC => Protocol::Grpc,
+        OTEL_EXPORTER_OTLP_PROTOCOL_HTTP_JSON => Protocol::HttpJson,
         _ => Protocol::HttpBinary,
     }
 }
@@ -121,11 +126,12 @@ fn default_endpoint(protocol: Protocol) -> String {
     match protocol {
         Protocol::Grpc => OTEL_EXPORTER_OTLP_GRPC_ENDPOINT_DEFAULT.to_string(),
         Protocol::HttpBinary => OTEL_EXPORTER_OTLP_HTTP_ENDPOINT_DEFAULT.to_string(),
+        Protocol::HttpJson => OTEL_EXPORTER_OTLP_HTTP_ENDPOINT_DEFAULT.to_string(),
     }
 }
 
 /// default user-agent headers
-#[cfg(any(feature = "grpc-tonic", feature = "http-proto"))]
+#[cfg(any(feature = "grpc-tonic", feature = "http-proto", feature = "http-json"))]
 fn default_headers() -> std::collections::HashMap<String, String> {
     let mut headers = std::collections::HashMap::new();
     headers.insert(
@@ -148,7 +154,7 @@ impl HasExportConfig for TonicExporterBuilder {
     }
 }
 
-#[cfg(feature = "http-proto")]
+#[cfg(any(feature = "http-proto", feature = "http-json"))]
 impl HasExportConfig for HttpExporterBuilder {
     fn export_config(&mut self) -> &mut ExportConfig {
         &mut self.exporter_config
@@ -210,7 +216,7 @@ impl<B: HasExportConfig> WithExportConfig for B {
     }
 }
 
-#[cfg(any(feature = "grpc-tonic", feature = "http-proto"))]
+#[cfg(any(feature = "grpc-tonic", feature = "http-proto", feature = "http-json"))]
 fn parse_header_string(value: &str) -> impl Iterator<Item = (&str, &str)> {
     value
         .split_terminator(',')
@@ -218,7 +224,7 @@ fn parse_header_string(value: &str) -> impl Iterator<Item = (&str, &str)> {
         .filter_map(parse_header_key_value_string)
 }
 
-#[cfg(any(feature = "grpc-tonic", feature = "http-proto"))]
+#[cfg(any(feature = "grpc-tonic", feature = "http-proto", feature = "http-json"))]
 fn parse_header_key_value_string(key_value_string: &str) -> Option<(&str, &str)> {
     key_value_string
         .split_once('=')
@@ -227,7 +233,7 @@ fn parse_header_key_value_string(key_value_string: &str) -> Option<(&str, &str)>
 }
 
 #[cfg(test)]
-#[cfg(any(feature = "grpc-tonic", feature = "http-proto"))]
+#[cfg(any(feature = "grpc-tonic", feature = "http-proto", feature = "http-json"))]
 mod tests {
 
     pub(crate) fn run_env_test<T, F>(env_vars: T, f: F)
@@ -245,7 +251,7 @@ mod tests {
         )
     }
 
-    #[cfg(feature = "http-proto")]
+    #[cfg(any(feature = "http-proto", feature = "http-json"))]
     #[test]
     fn test_default_http_endpoint() {
         let exporter_builder = crate::new_exporter().http();
diff --git a/opentelemetry-otlp/src/lib.rs b/opentelemetry-otlp/src/lib.rs
index 0b96ae039d..b04cc30a49 100644
--- a/opentelemetry-otlp/src/lib.rs
+++ b/opentelemetry-otlp/src/lib.rs
@@ -104,6 +104,7 @@
 //! * `reqwest-blocking-client`: Use reqwest blocking http client.
 //! * `reqwest-client`: Use reqwest http client.
 //! * `reqwest-rustls`: Use reqwest with TLS.
+//! * `http-json`: Use http as transport layer, JSON as body format.
 //!
 //! # Kitchen Sink Full Configuration
 //!
@@ -247,7 +248,7 @@ pub use crate::exporter::{
 
 use opentelemetry_sdk::export::ExportError;
 
-#[cfg(feature = "http-proto")]
+#[cfg(any(feature = "http-proto", feature = "http-json"))]
 pub use crate::exporter::http::HttpExporterBuilder;
 
 #[cfg(feature = "grpc-tonic")]
@@ -278,7 +279,7 @@ impl OtlpExporterPipeline {
     /// and build the exporter.
     ///
     /// This exporter can be used in both `tracing` and `metrics` pipeline.
-    #[cfg(feature = "http-proto")]
+    #[cfg(any(feature = "http-proto", feature = "http-json"))]
     pub fn http(self) -> HttpExporterBuilder {
         HttpExporterBuilder::default()
     }
@@ -314,7 +315,7 @@ pub enum Error {
     Transport(#[from] tonic::transport::Error),
 
     /// Wrap the [`tonic::codegen::http::uri::InvalidUri`] error
-    #[cfg(any(feature = "grpc-tonic", feature = "http-proto"))]
+    #[cfg(any(feature = "grpc-tonic", feature = "http-proto", feature = "http-json"))]
     #[error("invalid URI {0}")]
     InvalidUri(#[from] http::uri::InvalidUri),
 
@@ -329,32 +330,32 @@ pub enum Error {
     },
 
     /// Http requests failed because no http client is provided.
-    #[cfg(feature = "http-proto")]
+    #[cfg(any(feature = "http-proto", feature = "http-json"))]
     #[error(
         "no http client, you must select one from features or provide your own implementation"
     )]
     NoHttpClient,
 
     /// Http requests failed.
-    #[cfg(feature = "http-proto")]
+    #[cfg(any(feature = "http-proto", feature = "http-json"))]
     #[error("http request failed with {0}")]
     RequestFailed(#[from] opentelemetry_http::HttpError),
 
     /// The provided value is invalid in HTTP headers.
-    #[cfg(any(feature = "grpc-tonic", feature = "http-proto"))]
+    #[cfg(any(feature = "grpc-tonic", feature = "http-proto", feature = "http-json"))]
     #[error("http header value error {0}")]
     InvalidHeaderValue(#[from] http::header::InvalidHeaderValue),
 
     /// The provided name is invalid in HTTP headers.
-    #[cfg(any(feature = "grpc-tonic", feature = "http-proto"))]
+    #[cfg(any(feature = "grpc-tonic", feature = "http-proto", feature = "http-json"))]
     #[error("http header name error {0}")]
     InvalidHeaderName(#[from] http::header::InvalidHeaderName),
 
     /// Prost encode failed
-    #[cfg(feature = "http-proto")]
+    #[cfg(any(feature = "http-proto", all(feature = "http-json", not(feature = "trace"))))]
     #[error("prost encoding error {0}")]
     EncodeError(#[from] prost::EncodeError),
-
+    
     /// The lock in exporters has been poisoned.
     #[cfg(feature = "metrics")]
     #[error("the lock of the {0} has been poisoned")]
@@ -393,10 +394,10 @@ impl ExportError for Error {
 pub enum Protocol {
     /// GRPC protocol
     Grpc,
-    // TODO add support for other protocols
-    // HttpJson,
     /// HTTP protocol with binary protobuf
     HttpBinary,
+    /// HTTP protocol with JSON payload
+    HttpJson,
 }
 
 #[derive(Debug, Default)]
diff --git a/opentelemetry-otlp/src/span.rs b/opentelemetry-otlp/src/span.rs
index 76383f2f04..3b0a543e31 100644
--- a/opentelemetry-otlp/src/span.rs
+++ b/opentelemetry-otlp/src/span.rs
@@ -19,7 +19,7 @@ use sdk::runtime::RuntimeChannel;
 #[cfg(feature = "grpc-tonic")]
 use crate::exporter::tonic::TonicExporterBuilder;
 
-#[cfg(feature = "http-proto")]
+#[cfg(any(feature = "http-proto", feature = "http-json"))]
 use crate::exporter::http::HttpExporterBuilder;
 
 use crate::{NoExporterConfig, OtlpPipeline};
@@ -187,7 +187,7 @@ pub enum SpanExporterBuilder {
     #[cfg(feature = "grpc-tonic")]
     Tonic(TonicExporterBuilder),
     /// Http span exporter builder
-    #[cfg(feature = "http-proto")]
+    #[cfg(any(feature = "http-proto", feature = "http-json"))]
     Http(HttpExporterBuilder),
 }
 
@@ -197,7 +197,7 @@ impl SpanExporterBuilder {
         match self {
             #[cfg(feature = "grpc-tonic")]
             SpanExporterBuilder::Tonic(builder) => builder.build_span_exporter(),
-            #[cfg(feature = "http-proto")]
+            #[cfg(any(feature = "http-proto", feature = "http-json"))]
             SpanExporterBuilder::Http(builder) => builder.build_span_exporter(),
         }
     }
@@ -210,7 +210,7 @@ impl From<TonicExporterBuilder> for SpanExporterBuilder {
     }
 }
 
-#[cfg(feature = "http-proto")]
+#[cfg(any(feature = "http-proto", feature = "http-json"))]
 impl From<HttpExporterBuilder> for SpanExporterBuilder {
     fn from(exporter: HttpExporterBuilder) -> Self {
         SpanExporterBuilder::Http(exporter)

From 576a56d18afc8331942bc0e011e78711c88fca40 Mon Sep 17 00:00:00 2001
From: Ramajeyam Gopalraj <ramgdev@gmail.com>
Date: Tue, 27 Feb 2024 16:26:13 -0500
Subject: [PATCH 02/22] prototype json serialization

---
 opentelemetry-otlp/Cargo.toml                  |  2 +-
 .../src/exporter/http/metrics.rs               |  2 +-
 opentelemetry-otlp/src/exporter/http/trace.rs  | 18 +++++++++++++-----
 opentelemetry-otlp/src/exporter/mod.rs         |  6 +++---
 4 files changed, 18 insertions(+), 10 deletions(-)

diff --git a/opentelemetry-otlp/Cargo.toml b/opentelemetry-otlp/Cargo.toml
index 70668cf2cd..84163d8be6 100644
--- a/opentelemetry-otlp/Cargo.toml
+++ b/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 }
+opentelemetry-proto = { version = "0.5", path = "../opentelemetry-proto", default-features = false,  features=["with-serde"] }
 opentelemetry-semantic-conventions = { version = "0.14", path = "../opentelemetry-semantic-conventions" }
 
 prost = { workspace = true, optional = true }
diff --git a/opentelemetry-otlp/src/exporter/http/metrics.rs b/opentelemetry-otlp/src/exporter/http/metrics.rs
index b5ec92eb63..6bcdb99f42 100644
--- a/opentelemetry-otlp/src/exporter/http/metrics.rs
+++ b/opentelemetry-otlp/src/exporter/http/metrics.rs
@@ -61,7 +61,7 @@ fn build_body(metrics: &mut ResourceMetrics) -> Result<(Vec<u8>, &'static str)>
 }
 
 #[cfg(not(feature = "http-proto"))]
-fn build_body(metrics: &mut ResourceMetrics) -> Result<(Vec<u8>, &'static str)> {
+fn build_body(_metrics: &mut ResourceMetrics) -> Result<(Vec<u8>, &'static str)> {
     Err(MetricsError::Other(
         "No http protocol configured. Enable one via `http-proto`".into(),
     ))
diff --git a/opentelemetry-otlp/src/exporter/http/trace.rs b/opentelemetry-otlp/src/exporter/http/trace.rs
index e9a8606c88..a715ed1e89 100644
--- a/opentelemetry-otlp/src/exporter/http/trace.rs
+++ b/opentelemetry-otlp/src/exporter/http/trace.rs
@@ -71,15 +71,23 @@ 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;
 
     let req = ExportTraceServiceRequest {
         resource_spans: spans.into_iter().map(Into::into).collect(),
     };
-    let mut buf = vec![];
-    req.encode(&mut buf).map_err(crate::Error::from)?;
-
-    Ok((buf, "application/x-protobuf"))    
+    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";
+    }
+    Ok((buf, ctype))
 }
 
 #[cfg(not(any(feature = "http-proto", feature = "http-json")))]
diff --git a/opentelemetry-otlp/src/exporter/mod.rs b/opentelemetry-otlp/src/exporter/mod.rs
index 6403222446..80e52eb106 100644
--- a/opentelemetry-otlp/src/exporter/mod.rs
+++ b/opentelemetry-otlp/src/exporter/mod.rs
@@ -28,13 +28,13 @@ pub const OTEL_EXPORTER_OTLP_PROTOCOL: &str = "OTEL_EXPORTER_OTLP_PROTOCOL";
 /// Compression algorithm to use, defaults to none.
 pub const OTEL_EXPORTER_OTLP_COMPRESSION: &str = "OTEL_EXPORTER_OTLP_COMPRESSION";
 
-#[cfg(feature = "http-proto")]
+#[cfg(any(feature = "http-proto", not(all(feature = "http-json", feature = "trace"))))]
 /// Default protocol, using http-proto.
 pub const OTEL_EXPORTER_OTLP_PROTOCOL_DEFAULT: &str = OTEL_EXPORTER_OTLP_PROTOCOL_HTTP_PROTOBUF;
-#[cfg(all(feature = "http-json", feature = "trace", not(any(feature = "http-proto", feature = "grpc-tonic"))))]
+#[cfg(all(feature = "http-json", feature = "trace", not(feature = "http-proto")))]
 /// Default protocol, using http-json.
 pub const OTEL_EXPORTER_OTLP_PROTOCOL_DEFAULT: &str = OTEL_EXPORTER_OTLP_PROTOCOL_HTTP_JSON;
-#[cfg(all(feature = "grpc-tonic", not(any(feature = "http-proto", feature = "http-json"))))]
+#[cfg(all(feature = "grpc-tonic", not(all(feature = "http-proto", feature = "http-json", feature = "trace"))))]
 /// Default protocol, using grpc as http-proto or http-json feature is not enabled.
 pub const OTEL_EXPORTER_OTLP_PROTOCOL_DEFAULT: &str = OTEL_EXPORTER_OTLP_PROTOCOL_GRPC;
 #[cfg(not(any(any(feature = "grpc-tonic", feature = "http-proto", feature = "http-json"))))]

From d13ab4b22b2ffe4caa887ec9f17bd8fc7d474e01 Mon Sep 17 00:00:00 2001
From: Ramajeyam Gopalraj <ramgdev@gmail.com>
Date: Tue, 27 Feb 2024 16:55:52 -0500
Subject: [PATCH 03/22] fix default protocol

---
 opentelemetry-otlp/src/exporter/mod.rs | 10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/opentelemetry-otlp/src/exporter/mod.rs b/opentelemetry-otlp/src/exporter/mod.rs
index 80e52eb106..06b76a7c96 100644
--- a/opentelemetry-otlp/src/exporter/mod.rs
+++ b/opentelemetry-otlp/src/exporter/mod.rs
@@ -28,13 +28,13 @@ pub const OTEL_EXPORTER_OTLP_PROTOCOL: &str = "OTEL_EXPORTER_OTLP_PROTOCOL";
 /// Compression algorithm to use, defaults to none.
 pub const OTEL_EXPORTER_OTLP_COMPRESSION: &str = "OTEL_EXPORTER_OTLP_COMPRESSION";
 
-#[cfg(any(feature = "http-proto", not(all(feature = "http-json", feature = "trace"))))]
-/// Default protocol, using http-proto.
-pub const OTEL_EXPORTER_OTLP_PROTOCOL_DEFAULT: &str = OTEL_EXPORTER_OTLP_PROTOCOL_HTTP_PROTOBUF;
-#[cfg(all(feature = "http-json", feature = "trace", not(feature = "http-proto")))]
+#[cfg(all(feature = "http-json", feature = "trace", not(all(feature = "http-proto", feature = "grpc-toni"))))]
 /// Default protocol, using http-json.
 pub const OTEL_EXPORTER_OTLP_PROTOCOL_DEFAULT: &str = OTEL_EXPORTER_OTLP_PROTOCOL_HTTP_JSON;
-#[cfg(all(feature = "grpc-tonic", not(all(feature = "http-proto", feature = "http-json", feature = "trace"))))]
+#[cfg(all(feature = "http-proto", not(all(feature = "http-json", feature = "trace"))))]
+/// Default protocol, using http-proto.
+pub const OTEL_EXPORTER_OTLP_PROTOCOL_DEFAULT: &str = OTEL_EXPORTER_OTLP_PROTOCOL_HTTP_PROTOBUF;
+#[cfg(all(feature = "grpc-tonic", not(all(feature = "http-proto", feature = "http-json"))))]
 /// Default protocol, using grpc as http-proto or http-json feature is not enabled.
 pub const OTEL_EXPORTER_OTLP_PROTOCOL_DEFAULT: &str = OTEL_EXPORTER_OTLP_PROTOCOL_GRPC;
 #[cfg(not(any(any(feature = "grpc-tonic", feature = "http-proto", feature = "http-json"))))]

From ed4fc0346ceb4088075786bc7d766bab76f0fb4a Mon Sep 17 00:00:00 2001
From: Ramajeyam Gopalraj <ramgdev@gmail.com>
Date: Tue, 27 Feb 2024 17:11:16 -0500
Subject: [PATCH 04/22] fix typo

---
 opentelemetry-otlp/src/exporter/mod.rs | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/opentelemetry-otlp/src/exporter/mod.rs b/opentelemetry-otlp/src/exporter/mod.rs
index 06b76a7c96..8f777a8821 100644
--- a/opentelemetry-otlp/src/exporter/mod.rs
+++ b/opentelemetry-otlp/src/exporter/mod.rs
@@ -28,10 +28,10 @@ pub const OTEL_EXPORTER_OTLP_PROTOCOL: &str = "OTEL_EXPORTER_OTLP_PROTOCOL";
 /// Compression algorithm to use, defaults to none.
 pub const OTEL_EXPORTER_OTLP_COMPRESSION: &str = "OTEL_EXPORTER_OTLP_COMPRESSION";
 
-#[cfg(all(feature = "http-json", feature = "trace", not(all(feature = "http-proto", feature = "grpc-toni"))))]
+#[cfg(all(feature = "trace", not(feature = "http-proto"), not(feature = "grpc-tonic")))]
 /// Default protocol, using http-json.
 pub const OTEL_EXPORTER_OTLP_PROTOCOL_DEFAULT: &str = OTEL_EXPORTER_OTLP_PROTOCOL_HTTP_JSON;
-#[cfg(all(feature = "http-proto", not(all(feature = "http-json", feature = "trace"))))]
+#[cfg(feature = "http-proto")]
 /// Default protocol, using http-proto.
 pub const OTEL_EXPORTER_OTLP_PROTOCOL_DEFAULT: &str = OTEL_EXPORTER_OTLP_PROTOCOL_HTTP_PROTOBUF;
 #[cfg(all(feature = "grpc-tonic", not(all(feature = "http-proto", feature = "http-json"))))]

From 587c341f6b42109108cefdeb0d43cbbda7c69e9b Mon Sep 17 00:00:00 2001
From: Ramajeyam Gopalraj <ramgdev@gmail.com>
Date: Tue, 27 Feb 2024 20:37:43 -0500
Subject: [PATCH 05/22] use default protocol for HttpConfig

---
 opentelemetry-otlp/src/exporter/http/mod.rs | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/opentelemetry-otlp/src/exporter/http/mod.rs b/opentelemetry-otlp/src/exporter/http/mod.rs
index ef64662038..c7042a0f13 100644
--- a/opentelemetry-otlp/src/exporter/http/mod.rs
+++ b/opentelemetry-otlp/src/exporter/http/mod.rs
@@ -1,5 +1,5 @@
 use crate::{
-    ExportConfig, Protocol, OTEL_EXPORTER_OTLP_ENDPOINT, OTEL_EXPORTER_OTLP_HEADERS,
+    ExportConfig, OTEL_EXPORTER_OTLP_ENDPOINT, OTEL_EXPORTER_OTLP_HEADERS,
     OTEL_EXPORTER_OTLP_TIMEOUT,
 };
 use http::{HeaderName, HeaderValue, Uri};
@@ -10,7 +10,7 @@ use std::str::FromStr;
 use std::sync::{Arc, Mutex};
 use std::time::Duration;
 
-use super::{default_headers, parse_header_string};
+use super::{default_headers, default_protocol, parse_header_string};
 
 #[cfg(feature = "metrics")]
 mod metrics;
@@ -98,7 +98,7 @@ impl Default for HttpExporterBuilder {
     fn default() -> Self {
         HttpExporterBuilder {
             exporter_config: ExportConfig {
-                protocol: Protocol::HttpBinary,
+                protocol: default_protocol(),
                 ..ExportConfig::default()
             },
             http_config: HttpConfig {

From d460bda47217b73408b670842f1f4c6a5476543a Mon Sep 17 00:00:00 2001
From: Ramji <ramgdev@users.noreply.github.com>
Date: Wed, 28 Feb 2024 12:24:32 -0500
Subject: [PATCH 06/22] Update opentelemetry-otlp/src/exporter/http/trace.rs

Co-authored-by: Zhongyang Wu <zhongyang.wu@outlook.com>
---
 opentelemetry-otlp/src/exporter/http/trace.rs | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/opentelemetry-otlp/src/exporter/http/trace.rs b/opentelemetry-otlp/src/exporter/http/trace.rs
index a715ed1e89..65aab88d2f 100644
--- a/opentelemetry-otlp/src/exporter/http/trace.rs
+++ b/opentelemetry-otlp/src/exporter/http/trace.rs
@@ -82,7 +82,7 @@ fn build_body(spans: Vec<SpanData>) -> TraceResult<(Vec<u8>, &'static str)> {
         buf = req.encode_to_vec();
         ctype = "application/x-protobuf";
     }
-    #[cfg(all(feature = "http-json", not(feature = "http=proto")))]{
+    #[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";

From da76734f0b04b8464e43785f2da981bafa010ac2 Mon Sep 17 00:00:00 2001
From: Ramajeyam Gopalraj <ramgdev@gmail.com>
Date: Thu, 29 Feb 2024 16:20:12 -0500
Subject: [PATCH 07/22] address review comments

---
 opentelemetry-otlp/Cargo.toml                 |  4 ++--
 opentelemetry-otlp/src/exporter/http/trace.rs | 24 +++++++++++--------
 2 files changed, 16 insertions(+), 12 deletions(-)

diff --git a/opentelemetry-otlp/Cargo.toml b/opentelemetry-otlp/Cargo.toml
index 84163d8be6..d1fcd2025f 100644
--- a/opentelemetry-otlp/Cargo.toml
+++ b/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"]
diff --git a/opentelemetry-otlp/src/exporter/http/trace.rs b/opentelemetry-otlp/src/exporter/http/trace.rs
index 65aab88d2f..f472f157a0 100644
--- a/opentelemetry-otlp/src/exporter/http/trace.rs
+++ b/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))
 }
 

From aa74b9cf180edbaf96b580c65986836965e49004 Mon Sep 17 00:00:00 2001
From: Ramajeyam Gopalraj <ramgdev@gmail.com>
Date: Thu, 29 Feb 2024 16:43:42 -0500
Subject: [PATCH 08/22] run pre-commit script

---
 opentelemetry-otlp/src/exporter/http/trace.rs | 15 +++++++++------
 opentelemetry-otlp/src/exporter/mod.rs        | 11 +++++++++--
 opentelemetry-otlp/src/lib.rs                 |  7 +++++--
 3 files changed, 23 insertions(+), 10 deletions(-)

diff --git a/opentelemetry-otlp/src/exporter/http/trace.rs b/opentelemetry-otlp/src/exporter/http/trace.rs
index f472f157a0..66aa62e53d 100644
--- a/opentelemetry-otlp/src/exporter/http/trace.rs
+++ b/opentelemetry-otlp/src/exporter/http/trace.rs
@@ -70,26 +70,29 @@ impl SpanExporter for OtlpHttpClient {
 
 #[cfg(any(feature = "http-proto", feature = "http-json"))]
 fn build_body(spans: Vec<SpanData>) -> TraceResult<(Vec<u8>, &'static str)> {
+    use crate::exporter::default_protocol;
+    #[cfg(feature = "http-json")]
+    use crate::Protocol;
     use opentelemetry_proto::tonic::collector::trace::v1::ExportTraceServiceRequest;
+    #[cfg(feature = "http-proto")]
     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;
     match default_protocol() {
+        #[cfg(feature = "http-json")]
         Protocol::HttpJson => {
             let json_struct = serde_json::to_string_pretty(&req).unwrap();
             buf = json_struct.into();
-            ctype = "application/json";    
-        },
+            ctype = "application/json";
+        }
         _ => {
             buf = req.encode_to_vec();
-            ctype = "application/x-protobuf";    
-        },
+            ctype = "application/x-protobuf";
+        }
     };
     Ok((buf, ctype))
 }
diff --git a/opentelemetry-otlp/src/exporter/mod.rs b/opentelemetry-otlp/src/exporter/mod.rs
index 8f777a8821..ff99effe6f 100644
--- a/opentelemetry-otlp/src/exporter/mod.rs
+++ b/opentelemetry-otlp/src/exporter/mod.rs
@@ -28,13 +28,20 @@ pub const OTEL_EXPORTER_OTLP_PROTOCOL: &str = "OTEL_EXPORTER_OTLP_PROTOCOL";
 /// Compression algorithm to use, defaults to none.
 pub const OTEL_EXPORTER_OTLP_COMPRESSION: &str = "OTEL_EXPORTER_OTLP_COMPRESSION";
 
-#[cfg(all(feature = "trace", not(feature = "http-proto"), not(feature = "grpc-tonic")))]
+#[cfg(all(
+    feature = "trace",
+    not(feature = "http-proto"),
+    not(feature = "grpc-tonic")
+))]
 /// Default protocol, using http-json.
 pub const OTEL_EXPORTER_OTLP_PROTOCOL_DEFAULT: &str = OTEL_EXPORTER_OTLP_PROTOCOL_HTTP_JSON;
 #[cfg(feature = "http-proto")]
 /// Default protocol, using http-proto.
 pub const OTEL_EXPORTER_OTLP_PROTOCOL_DEFAULT: &str = OTEL_EXPORTER_OTLP_PROTOCOL_HTTP_PROTOBUF;
-#[cfg(all(feature = "grpc-tonic", not(all(feature = "http-proto", feature = "http-json"))))]
+#[cfg(all(
+    feature = "grpc-tonic",
+    not(all(feature = "http-proto", feature = "http-json"))
+))]
 /// Default protocol, using grpc as http-proto or http-json feature is not enabled.
 pub const OTEL_EXPORTER_OTLP_PROTOCOL_DEFAULT: &str = OTEL_EXPORTER_OTLP_PROTOCOL_GRPC;
 #[cfg(not(any(any(feature = "grpc-tonic", feature = "http-proto", feature = "http-json"))))]
diff --git a/opentelemetry-otlp/src/lib.rs b/opentelemetry-otlp/src/lib.rs
index b04cc30a49..cec17857b3 100644
--- a/opentelemetry-otlp/src/lib.rs
+++ b/opentelemetry-otlp/src/lib.rs
@@ -352,10 +352,13 @@ pub enum Error {
     InvalidHeaderName(#[from] http::header::InvalidHeaderName),
 
     /// Prost encode failed
-    #[cfg(any(feature = "http-proto", all(feature = "http-json", not(feature = "trace"))))]
+    #[cfg(any(
+        feature = "http-proto",
+        all(feature = "http-json", not(feature = "trace"))
+    ))]
     #[error("prost encoding error {0}")]
     EncodeError(#[from] prost::EncodeError),
-    
+
     /// The lock in exporters has been poisoned.
     #[cfg(feature = "metrics")]
     #[error("the lock of the {0} has been poisoned")]

From efa8588bda77f5d41ba9849e8fc01ae619e59736 Mon Sep 17 00:00:00 2001
From: Ramajeyam Gopalraj <ramgdev@gmail.com>
Date: Thu, 29 Feb 2024 17:10:19 -0500
Subject: [PATCH 09/22] fix dependency

---
 opentelemetry-otlp/src/exporter/http/trace.rs | 1 -
 1 file changed, 1 deletion(-)

diff --git a/opentelemetry-otlp/src/exporter/http/trace.rs b/opentelemetry-otlp/src/exporter/http/trace.rs
index 66aa62e53d..3052c41b11 100644
--- a/opentelemetry-otlp/src/exporter/http/trace.rs
+++ b/opentelemetry-otlp/src/exporter/http/trace.rs
@@ -74,7 +74,6 @@ fn build_body(spans: Vec<SpanData>) -> TraceResult<(Vec<u8>, &'static str)> {
     #[cfg(feature = "http-json")]
     use crate::Protocol;
     use opentelemetry_proto::tonic::collector::trace::v1::ExportTraceServiceRequest;
-    #[cfg(feature = "http-proto")]
     use prost::Message;
 
     let req = ExportTraceServiceRequest {

From 04593ece4acb87569e903fc3df4e72d3af5ab6cb Mon Sep 17 00:00:00 2001
From: Ramji <ramgdev@users.noreply.github.com>
Date: Sun, 3 Mar 2024 18:15:26 -0500
Subject: [PATCH 10/22] Update mod.rs

fix format
---
 opentelemetry-otlp/src/exporter/mod.rs | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/opentelemetry-otlp/src/exporter/mod.rs b/opentelemetry-otlp/src/exporter/mod.rs
index bb6df67258..8c41174730 100644
--- a/opentelemetry-otlp/src/exporter/mod.rs
+++ b/opentelemetry-otlp/src/exporter/mod.rs
@@ -231,7 +231,7 @@ fn parse_header_string(value: &str) -> impl Iterator<Item = (&str, String)> {
         .filter_map(parse_header_key_value_string)
 }
 
-#[cfg(any(feature = "grpc-tonic", feature = "http-proto", feature="http-json"))]
+#[cfg(any(feature = "grpc-tonic", feature = "http-proto", feature = "http-json"))]
 fn url_decode(value: &str) -> Option<String> {
     let mut result = String::with_capacity(value.len());
     let mut chars_to_decode = Vec::<u8>::new();

From 277df671e89b15926e038be60510aba3de9f1ff4 Mon Sep 17 00:00:00 2001
From: Ramajeyam Gopalraj <ramgdev@gmail.com>
Date: Sun, 3 Mar 2024 18:39:22 -0500
Subject: [PATCH 11/22] unit test default endpoint

---
 opentelemetry-otlp/src/exporter/mod.rs | 13 +++++++++++++
 1 file changed, 13 insertions(+)

diff --git a/opentelemetry-otlp/src/exporter/mod.rs b/opentelemetry-otlp/src/exporter/mod.rs
index 8c41174730..c022070972 100644
--- a/opentelemetry-otlp/src/exporter/mod.rs
+++ b/opentelemetry-otlp/src/exporter/mod.rs
@@ -315,6 +315,19 @@ mod tests {
         );
     }
 
+    #[cfg(feature = "http-json")]
+    #[test]
+    fn test_default_http_json_endpoint() {
+        use crate::WithExportConfig;
+
+        let exporter_builder = crate::new_exporter().http().with_protocol(crate::Protocol::HttpJson);
+
+        assert_eq!(
+            exporter_builder.exporter_config.endpoint,
+            "http://localhost:4318"
+        );
+    }
+
     #[test]
     fn test_url_decode() {
         let test_cases = vec![

From 5d5e06eb0bb198ab05449398193e0a976d59656f Mon Sep 17 00:00:00 2001
From: Ramajeyam Gopalraj <ramgdev@gmail.com>
Date: Sun, 3 Mar 2024 19:08:35 -0500
Subject: [PATCH 12/22] test default protocol

---
 opentelemetry-otlp/src/exporter/mod.rs | 19 ++++++++++++++-----
 1 file changed, 14 insertions(+), 5 deletions(-)

diff --git a/opentelemetry-otlp/src/exporter/mod.rs b/opentelemetry-otlp/src/exporter/mod.rs
index c022070972..1031e8b038 100644
--- a/opentelemetry-otlp/src/exporter/mod.rs
+++ b/opentelemetry-otlp/src/exporter/mod.rs
@@ -30,6 +30,7 @@ pub const OTEL_EXPORTER_OTLP_COMPRESSION: &str = "OTEL_EXPORTER_OTLP_COMPRESSION
 
 #[cfg(all(
     feature = "trace",
+    feature = "http-json",
     not(feature = "http-proto"),
     not(feature = "grpc-tonic")
 ))]
@@ -315,17 +316,25 @@ mod tests {
         );
     }
 
-    #[cfg(feature = "http-json")]
+    #[cfg(all(
+        feature = "trace",
+        feature = "http-json",
+        not(feature = "http-proto"),
+        not(feature = "grpc-tonic")
+    ))]
     #[test]
-    fn test_default_http_json_endpoint() {
-        use crate::WithExportConfig;
-
-        let exporter_builder = crate::new_exporter().http().with_protocol(crate::Protocol::HttpJson);
+    fn test_http_json_defaults() {
+        let exporter_builder = crate::new_exporter().http();
 
         assert_eq!(
             exporter_builder.exporter_config.endpoint,
             "http://localhost:4318"
         );
+
+        assert_eq!(
+            exporter_builder.exporter_config.protocol,
+            crate::Protocol::HttpJson
+        );
     }
 
     #[test]

From f93058c197c223b7d00d6fb623a5eebcb7fe8e8b Mon Sep 17 00:00:00 2001
From: Ramajeyam Gopalraj <ramgdev@gmail.com>
Date: Sun, 17 Mar 2024 22:11:30 -0400
Subject: [PATCH 13/22] enable http-json for all signals

---
 opentelemetry-otlp/src/exporter/http/logs.rs  | 24 +++++--
 .../src/exporter/http/metrics.rs              | 23 +++++--
 opentelemetry-otlp/src/exporter/mod.rs        | 62 +++++++++++--------
 3 files changed, 75 insertions(+), 34 deletions(-)

diff --git a/opentelemetry-otlp/src/exporter/http/logs.rs b/opentelemetry-otlp/src/exporter/http/logs.rs
index 6bb8b76493..3fb4d43a43 100644
--- a/opentelemetry-otlp/src/exporter/http/logs.rs
+++ b/opentelemetry-otlp/src/exporter/http/logs.rs
@@ -52,18 +52,32 @@ impl LogExporter for OtlpHttpClient {
     }
 }
 
-#[cfg(feature = "http-proto")]
+#[cfg(any(feature = "http-proto", feature = "http-json"))]
 fn build_body(logs: Vec<LogData>) -> LogResult<(Vec<u8>, &'static str)> {
+    use crate::exporter::default_protocol;
+    #[cfg(feature = "http-json")]
+    use crate::Protocol;
     use opentelemetry_proto::tonic::collector::logs::v1::ExportLogsServiceRequest;
     use prost::Message;
 
     let req = ExportLogsServiceRequest {
         resource_logs: logs.into_iter().map(Into::into).collect(),
     };
-    let mut buf = vec![];
-    req.encode(&mut buf).map_err(crate::Error::from)?;
-
-    Ok((buf, "application/x-protobuf"))
+    let buf;
+    let ctype;
+    match default_protocol() {
+        #[cfg(feature = "http-json")]
+        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))
 }
 
 #[cfg(not(feature = "http-proto"))]
diff --git a/opentelemetry-otlp/src/exporter/http/metrics.rs b/opentelemetry-otlp/src/exporter/http/metrics.rs
index 6bcdb99f42..509b244b38 100644
--- a/opentelemetry-otlp/src/exporter/http/metrics.rs
+++ b/opentelemetry-otlp/src/exporter/http/metrics.rs
@@ -48,16 +48,31 @@ impl MetricsClient for OtlpHttpClient {
     }
 }
 
-#[cfg(feature = "http-proto")]
+#[cfg(any(feature = "http-proto", feature = "http-json"))]
 fn build_body(metrics: &mut ResourceMetrics) -> Result<(Vec<u8>, &'static str)> {
+    use crate::exporter::default_protocol;
+    #[cfg(feature = "http-json")]
+    use crate::Protocol;
     use prost::Message;
 
     let req: opentelemetry_proto::tonic::collector::metrics::v1::ExportMetricsServiceRequest =
         (&*metrics).into();
-    let mut buf = vec![];
-    req.encode(&mut buf).map_err(crate::Error::from)?;
 
-    Ok((buf, "application/x-protobuf"))
+    let buf;
+    let ctype;
+    match default_protocol() {
+        #[cfg(feature = "http-json")]
+        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))
 }
 
 #[cfg(not(feature = "http-proto"))]
diff --git a/opentelemetry-otlp/src/exporter/mod.rs b/opentelemetry-otlp/src/exporter/mod.rs
index 1031e8b038..343878281b 100644
--- a/opentelemetry-otlp/src/exporter/mod.rs
+++ b/opentelemetry-otlp/src/exporter/mod.rs
@@ -28,26 +28,27 @@ pub const OTEL_EXPORTER_OTLP_PROTOCOL: &str = "OTEL_EXPORTER_OTLP_PROTOCOL";
 /// Compression algorithm to use, defaults to none.
 pub const OTEL_EXPORTER_OTLP_COMPRESSION: &str = "OTEL_EXPORTER_OTLP_COMPRESSION";
 
+/// Default protocol if no features are enabled.
+pub const OTEL_EXPORTER_OTLP_PROTOCOL_DEFAULT: &str = "";
+
 #[cfg(all(
-    feature = "trace",
     feature = "http-json",
-    not(feature = "http-proto"),
-    not(feature = "grpc-tonic")
+    not(all(feature = "grpc-tonic", feature = "http-proto"))
 ))]
 /// Default protocol, using http-json.
 pub const OTEL_EXPORTER_OTLP_PROTOCOL_DEFAULT: &str = OTEL_EXPORTER_OTLP_PROTOCOL_HTTP_JSON;
-#[cfg(feature = "http-proto")]
+#[cfg(all(
+    feature = "http-proto",
+    not(all(feature = "grpc-tonic", feature = "http-json"))
+))]
 /// Default protocol, using http-proto.
 pub const OTEL_EXPORTER_OTLP_PROTOCOL_DEFAULT: &str = OTEL_EXPORTER_OTLP_PROTOCOL_HTTP_PROTOBUF;
 #[cfg(all(
     feature = "grpc-tonic",
     not(all(feature = "http-proto", feature = "http-json"))
 ))]
-/// Default protocol, using grpc as http-proto or http-json feature is not enabled.
+/// Default protocol, using grpc
 pub const OTEL_EXPORTER_OTLP_PROTOCOL_DEFAULT: &str = OTEL_EXPORTER_OTLP_PROTOCOL_GRPC;
-#[cfg(not(any(any(feature = "grpc-tonic", feature = "http-proto", feature = "http-json"))))]
-/// Default protocol if no features are enabled.
-pub const OTEL_EXPORTER_OTLP_PROTOCOL_DEFAULT: &str = "";
 
 const OTEL_EXPORTER_OTLP_PROTOCOL_HTTP_PROTOBUF: &str = "http/protobuf";
 const OTEL_EXPORTER_OTLP_PROTOCOL_GRPC: &str = "grpc";
@@ -278,7 +279,6 @@ fn parse_header_key_value_string(key_value_string: &str) -> Option<(&str, String
 #[cfg(test)]
 #[cfg(any(feature = "grpc-tonic", feature = "http-proto", feature = "http-json"))]
 mod tests {
-
     pub(crate) fn run_env_test<T, F>(env_vars: T, f: F)
     where
         F: FnOnce(),
@@ -316,25 +316,37 @@ mod tests {
         );
     }
 
-    #[cfg(all(
-        feature = "trace",
-        feature = "http-json",
-        not(feature = "http-proto"),
-        not(feature = "grpc-tonic")
-    ))]
     #[test]
-    fn test_http_json_defaults() {
-        let exporter_builder = crate::new_exporter().http();
+    fn test_default_protocol() {
+        #[cfg(all(
+            feature = "http-json",
+            not(all(feature = "grpc-tonic", feature = "http-proto"))
+        ))]
+        {
+            assert_eq!(
+                crate::exporter::default_protocol(),
+                crate::Protocol::HttpJson
+            );
+        }
 
-        assert_eq!(
-            exporter_builder.exporter_config.endpoint,
-            "http://localhost:4318"
-        );
+        #[cfg(all(
+            feature = "http-proto",
+            not(all(feature = "grpc-tonic", feature = "http-json"))
+        ))]
+        {
+            assert_eq!(
+                crate::exporter::default_protocol(),
+                crate::Protocol::HttpBinary
+            );
+        }
 
-        assert_eq!(
-            exporter_builder.exporter_config.protocol,
-            crate::Protocol::HttpJson
-        );
+        #[cfg(all(
+            feature = "grpc-tonic",
+            not(all(feature = "http-proto", feature = "http-json"))
+        ))]
+        {
+            assert_eq!(crate::exporter::default_protocol(), crate::Protocol::Grpc);
+        }
     }
 
     #[test]

From 0f1a805c767bf43cad1b87d61b7cf033d66ef14a Mon Sep 17 00:00:00 2001
From: Ramajeyam Gopalraj <ramgdev@gmail.com>
Date: Sun, 17 Mar 2024 22:40:25 -0400
Subject: [PATCH 14/22] fix lint

---
 opentelemetry-otlp/src/exporter/mod.rs | 7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/opentelemetry-otlp/src/exporter/mod.rs b/opentelemetry-otlp/src/exporter/mod.rs
index 343878281b..f2de9b6da4 100644
--- a/opentelemetry-otlp/src/exporter/mod.rs
+++ b/opentelemetry-otlp/src/exporter/mod.rs
@@ -28,9 +28,6 @@ pub const OTEL_EXPORTER_OTLP_PROTOCOL: &str = "OTEL_EXPORTER_OTLP_PROTOCOL";
 /// Compression algorithm to use, defaults to none.
 pub const OTEL_EXPORTER_OTLP_COMPRESSION: &str = "OTEL_EXPORTER_OTLP_COMPRESSION";
 
-/// Default protocol if no features are enabled.
-pub const OTEL_EXPORTER_OTLP_PROTOCOL_DEFAULT: &str = "";
-
 #[cfg(all(
     feature = "http-json",
     not(all(feature = "grpc-tonic", feature = "http-proto"))
@@ -50,6 +47,10 @@ pub const OTEL_EXPORTER_OTLP_PROTOCOL_DEFAULT: &str = OTEL_EXPORTER_OTLP_PROTOCO
 /// Default protocol, using grpc
 pub const OTEL_EXPORTER_OTLP_PROTOCOL_DEFAULT: &str = OTEL_EXPORTER_OTLP_PROTOCOL_GRPC;
 
+#[cfg(not(any(feature = "grpc-tonic", feature = "http-proto", feature = "http-json")))]
+/// Default protocol if no features are enabled.
+pub const OTEL_EXPORTER_OTLP_PROTOCOL_DEFAULT: &str = "";
+
 const OTEL_EXPORTER_OTLP_PROTOCOL_HTTP_PROTOBUF: &str = "http/protobuf";
 const OTEL_EXPORTER_OTLP_PROTOCOL_GRPC: &str = "grpc";
 const OTEL_EXPORTER_OTLP_PROTOCOL_HTTP_JSON: &str = "http/json";

From e50ac0ee82f292d2aee312f3b59d4dd192b582d5 Mon Sep 17 00:00:00 2001
From: Ramajeyam Gopalraj <ramgdev@gmail.com>
Date: Tue, 19 Mar 2024 15:40:14 -0400
Subject: [PATCH 15/22] run precommit

---
 opentelemetry-otlp/src/exporter/mod.rs | 9 +++------
 1 file changed, 3 insertions(+), 6 deletions(-)

diff --git a/opentelemetry-otlp/src/exporter/mod.rs b/opentelemetry-otlp/src/exporter/mod.rs
index f2de9b6da4..a7ef38a940 100644
--- a/opentelemetry-otlp/src/exporter/mod.rs
+++ b/opentelemetry-otlp/src/exporter/mod.rs
@@ -28,21 +28,18 @@ pub const OTEL_EXPORTER_OTLP_PROTOCOL: &str = "OTEL_EXPORTER_OTLP_PROTOCOL";
 /// Compression algorithm to use, defaults to none.
 pub const OTEL_EXPORTER_OTLP_COMPRESSION: &str = "OTEL_EXPORTER_OTLP_COMPRESSION";
 
-#[cfg(all(
-    feature = "http-json",
-    not(all(feature = "grpc-tonic", feature = "http-proto"))
-))]
+#[cfg(feature = "http-json")]
 /// Default protocol, using http-json.
 pub const OTEL_EXPORTER_OTLP_PROTOCOL_DEFAULT: &str = OTEL_EXPORTER_OTLP_PROTOCOL_HTTP_JSON;
 #[cfg(all(
     feature = "http-proto",
-    not(all(feature = "grpc-tonic", feature = "http-json"))
+    not(any(feature = "grpc-tonic", feature = "http-json"))
 ))]
 /// Default protocol, using http-proto.
 pub const OTEL_EXPORTER_OTLP_PROTOCOL_DEFAULT: &str = OTEL_EXPORTER_OTLP_PROTOCOL_HTTP_PROTOBUF;
 #[cfg(all(
     feature = "grpc-tonic",
-    not(all(feature = "http-proto", feature = "http-json"))
+    not(any(feature = "http-proto", feature = "http-json"))
 ))]
 /// Default protocol, using grpc
 pub const OTEL_EXPORTER_OTLP_PROTOCOL_DEFAULT: &str = OTEL_EXPORTER_OTLP_PROTOCOL_GRPC;

From ad8322baea40f0fcb64853c8cb044ca50a10dec7 Mon Sep 17 00:00:00 2001
From: Ramajeyam Gopalraj <ramgdev@gmail.com>
Date: Mon, 25 Mar 2024 12:20:59 -0400
Subject: [PATCH 16/22] add unit test

---
 opentelemetry-otlp/src/exporter/http/logs.rs  | 19 +++---
 .../src/exporter/http/metrics.rs              | 20 +++---
 opentelemetry-otlp/src/exporter/http/trace.rs | 67 +++++++++++++++++--
 opentelemetry-otlp/src/exporter/mod.rs        |  6 +-
 4 files changed, 86 insertions(+), 26 deletions(-)

diff --git a/opentelemetry-otlp/src/exporter/http/logs.rs b/opentelemetry-otlp/src/exporter/http/logs.rs
index 3fb4d43a43..4f9cee9ecd 100644
--- a/opentelemetry-otlp/src/exporter/http/logs.rs
+++ b/opentelemetry-otlp/src/exporter/http/logs.rs
@@ -67,20 +67,23 @@ fn build_body(logs: Vec<LogData>) -> LogResult<(Vec<u8>, &'static str)> {
     let ctype;
     match default_protocol() {
         #[cfg(feature = "http-json")]
-        Protocol::HttpJson => {
-            let json_struct = serde_json::to_string_pretty(&req).unwrap();
-            buf = json_struct.into();
-            ctype = "application/json";
-        }
+        Protocol::HttpJson => match serde_json::to_string_pretty(&req) {
+            Ok(json) => {
+                buf = json.into();
+                ctype = "application/json";
+                Ok((buf, ctype))
+            }
+            Err(e) => Err(LogError::from(e.to_string())),
+        },
         _ => {
             buf = req.encode_to_vec();
             ctype = "application/x-protobuf";
+            Ok((buf, ctype))
         }
-    };
-    Ok((buf, ctype))
+    }
 }
 
-#[cfg(not(feature = "http-proto"))]
+#[cfg(not(any(feature = "http-proto", feature = "http-json")))]
 fn build_body(logs: Vec<LogData>) -> LogResult<(Vec<u8>, &'static str)> {
     Err(LogsError::Other(
         "No http protocol configured. Enable one via `http-proto`".into(),
diff --git a/opentelemetry-otlp/src/exporter/http/metrics.rs b/opentelemetry-otlp/src/exporter/http/metrics.rs
index 509b244b38..4d6862cebf 100644
--- a/opentelemetry-otlp/src/exporter/http/metrics.rs
+++ b/opentelemetry-otlp/src/exporter/http/metrics.rs
@@ -62,20 +62,24 @@ fn build_body(metrics: &mut ResourceMetrics) -> Result<(Vec<u8>, &'static str)>
     let ctype;
     match default_protocol() {
         #[cfg(feature = "http-json")]
-        Protocol::HttpJson => {
-            let json_struct = serde_json::to_string_pretty(&req).unwrap();
-            buf = json_struct.into();
-            ctype = "application/json";
-        }
+        #[cfg(feature = "http-json")]
+        Protocol::HttpJson => match serde_json::to_string_pretty(&req) {
+            Ok(json) => {
+                buf = json.into();
+                ctype = "application/json";
+                Ok((buf, ctype))
+            }
+            Err(e) => Err(MetricsError::Other(e.to_string())),
+        },
         _ => {
             buf = req.encode_to_vec();
             ctype = "application/x-protobuf";
+            Ok((buf, ctype))
         }
-    };
-    Ok((buf, ctype))
+    }
 }
 
-#[cfg(not(feature = "http-proto"))]
+#[cfg(not(any(feature = "http-proto", feature = "http-json")))]
 fn build_body(_metrics: &mut ResourceMetrics) -> Result<(Vec<u8>, &'static str)> {
     Err(MetricsError::Other(
         "No http protocol configured. Enable one via `http-proto`".into(),
diff --git a/opentelemetry-otlp/src/exporter/http/trace.rs b/opentelemetry-otlp/src/exporter/http/trace.rs
index 3052c41b11..b12f2fcef6 100644
--- a/opentelemetry-otlp/src/exporter/http/trace.rs
+++ b/opentelemetry-otlp/src/exporter/http/trace.rs
@@ -83,17 +83,20 @@ fn build_body(spans: Vec<SpanData>) -> TraceResult<(Vec<u8>, &'static str)> {
     let ctype;
     match default_protocol() {
         #[cfg(feature = "http-json")]
-        Protocol::HttpJson => {
-            let json_struct = serde_json::to_string_pretty(&req).unwrap();
-            buf = json_struct.into();
-            ctype = "application/json";
-        }
+        Protocol::HttpJson => match serde_json::to_string_pretty(&req) {
+            Ok(json) => {
+                buf = json.into();
+                ctype = "application/json";
+                Ok((buf, ctype))
+            }
+            Err(e) => Err(TraceError::from(e.to_string())),
+        },
         _ => {
             buf = req.encode_to_vec();
             ctype = "application/x-protobuf";
+            Ok((buf, ctype))
         }
-    };
-    Ok((buf, ctype))
+    }
 }
 
 #[cfg(not(any(feature = "http-proto", feature = "http-json")))]
@@ -102,3 +105,53 @@ fn build_body(spans: Vec<SpanData>) -> TraceResult<(Vec<u8>, &'static str)> {
         "No http protocol configured. Enable one via `http-proto` or `http-json`".into(),
     ))
 }
+
+#[cfg(any(feature = "http-proto", feature = "http-json"))]
+mod tests {
+    #[test]
+    fn test_build_body() {
+        use crate::exporter::http::trace::build_body;
+        use opentelemetry::trace::{
+            SpanContext, SpanId, SpanKind, Status, TraceFlags, TraceId, TraceState,
+        };
+        use opentelemetry_sdk::export::trace::SpanData;
+        use opentelemetry_sdk::trace::{SpanEvents, SpanLinks};
+        use opentelemetry_sdk::Resource;
+        use std::{borrow::Cow, time::SystemTime};
+
+        let span_data = (0..5)
+            .map(|_| SpanData {
+                span_context: SpanContext::new(
+                    TraceId::from_u128(12),
+                    SpanId::from_u64(12),
+                    TraceFlags::default(),
+                    false,
+                    TraceState::default(),
+                ),
+                parent_span_id: SpanId::from_u64(12),
+                span_kind: SpanKind::Client,
+                name: Default::default(),
+                start_time: SystemTime::now(),
+                end_time: SystemTime::now(),
+                attributes: Vec::new(),
+                dropped_attributes_count: 0,
+                events: SpanEvents::default(),
+                links: SpanLinks::default(),
+                status: Status::Unset,
+                resource: Cow::Owned(Resource::empty()),
+                instrumentation_lib: Default::default(),
+            })
+            .collect::<Vec<SpanData>>();
+
+        let result = build_body(span_data).unwrap();
+        match crate::exporter::default_protocol() {
+            #[cfg(feature = "http-json")]
+            crate::Protocol::HttpJson => {
+                assert_eq!(result.1, "application/json")
+            }
+            _ => {
+                assert_eq!(result.1, "application/x-protobuf")
+            }
+        };
+    }
+}
diff --git a/opentelemetry-otlp/src/exporter/mod.rs b/opentelemetry-otlp/src/exporter/mod.rs
index a7ef38a940..6be463ef9d 100644
--- a/opentelemetry-otlp/src/exporter/mod.rs
+++ b/opentelemetry-otlp/src/exporter/mod.rs
@@ -318,7 +318,7 @@ mod tests {
     fn test_default_protocol() {
         #[cfg(all(
             feature = "http-json",
-            not(all(feature = "grpc-tonic", feature = "http-proto"))
+            not(any(feature = "grpc-tonic", feature = "http-proto"))
         ))]
         {
             assert_eq!(
@@ -329,7 +329,7 @@ mod tests {
 
         #[cfg(all(
             feature = "http-proto",
-            not(all(feature = "grpc-tonic", feature = "http-json"))
+            not(any(feature = "grpc-tonic", feature = "http-json"))
         ))]
         {
             assert_eq!(
@@ -340,7 +340,7 @@ mod tests {
 
         #[cfg(all(
             feature = "grpc-tonic",
-            not(all(feature = "http-proto", feature = "http-json"))
+            not(any(feature = "http-proto", feature = "http-json"))
         ))]
         {
             assert_eq!(crate::exporter::default_protocol(), crate::Protocol::Grpc);

From 63fb044685521375a7a55517ad480c67d68febb1 Mon Sep 17 00:00:00 2001
From: Ramajeyam Gopalraj <ramgdev@gmail.com>
Date: Fri, 29 Mar 2024 11:22:37 -0400
Subject: [PATCH 17/22] update changelog

---
 opentelemetry-otlp/CHANGELOG.md | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/opentelemetry-otlp/CHANGELOG.md b/opentelemetry-otlp/CHANGELOG.md
index 28d519daa2..004f12f6b8 100644
--- a/opentelemetry-otlp/CHANGELOG.md
+++ b/opentelemetry-otlp/CHANGELOG.md
@@ -8,6 +8,10 @@
 
 ### Added
 
+- Aded `http/json` support for all signals ([#1585])
+
+[#1585]: https://github.com/open-telemetry/opentelemetry-rust/pull/1585
+
 - Added `DeltaTemporalitySelector` ([#1568])
 
 [#1568]: https://github.com/open-telemetry/opentelemetry-rust/pull/1568

From f9abf2401dfa039444b3179b995d1cd68e1f37bd Mon Sep 17 00:00:00 2001
From: Ramajeyam Gopalraj <ramgdev@gmail.com>
Date: Fri, 29 Mar 2024 17:00:14 -0400
Subject: [PATCH 18/22] address code review

---
 opentelemetry-otlp/src/exporter/http/logs.rs    | 14 ++------------
 opentelemetry-otlp/src/exporter/http/metrics.rs | 14 ++------------
 opentelemetry-otlp/src/exporter/http/trace.rs   | 14 ++------------
 3 files changed, 6 insertions(+), 36 deletions(-)

diff --git a/opentelemetry-otlp/src/exporter/http/logs.rs b/opentelemetry-otlp/src/exporter/http/logs.rs
index 4f9cee9ecd..7d92a24fc5 100644
--- a/opentelemetry-otlp/src/exporter/http/logs.rs
+++ b/opentelemetry-otlp/src/exporter/http/logs.rs
@@ -63,23 +63,13 @@ fn build_body(logs: Vec<LogData>) -> LogResult<(Vec<u8>, &'static str)> {
     let req = ExportLogsServiceRequest {
         resource_logs: logs.into_iter().map(Into::into).collect(),
     };
-    let buf;
-    let ctype;
     match default_protocol() {
         #[cfg(feature = "http-json")]
         Protocol::HttpJson => match serde_json::to_string_pretty(&req) {
-            Ok(json) => {
-                buf = json.into();
-                ctype = "application/json";
-                Ok((buf, ctype))
-            }
+            Ok(json) => Ok((json.into(), "application/json")),
             Err(e) => Err(LogError::from(e.to_string())),
         },
-        _ => {
-            buf = req.encode_to_vec();
-            ctype = "application/x-protobuf";
-            Ok((buf, ctype))
-        }
+        _ => Ok((req.encode_to_vec(), "application/x-protobuf")),
     }
 }
 
diff --git a/opentelemetry-otlp/src/exporter/http/metrics.rs b/opentelemetry-otlp/src/exporter/http/metrics.rs
index 4d6862cebf..528481e4bc 100644
--- a/opentelemetry-otlp/src/exporter/http/metrics.rs
+++ b/opentelemetry-otlp/src/exporter/http/metrics.rs
@@ -58,24 +58,14 @@ fn build_body(metrics: &mut ResourceMetrics) -> Result<(Vec<u8>, &'static str)>
     let req: opentelemetry_proto::tonic::collector::metrics::v1::ExportMetricsServiceRequest =
         (&*metrics).into();
 
-    let buf;
-    let ctype;
     match default_protocol() {
         #[cfg(feature = "http-json")]
         #[cfg(feature = "http-json")]
         Protocol::HttpJson => match serde_json::to_string_pretty(&req) {
-            Ok(json) => {
-                buf = json.into();
-                ctype = "application/json";
-                Ok((buf, ctype))
-            }
+            Ok(json) => Ok((json.into(), "application/json")),
             Err(e) => Err(MetricsError::Other(e.to_string())),
         },
-        _ => {
-            buf = req.encode_to_vec();
-            ctype = "application/x-protobuf";
-            Ok((buf, ctype))
-        }
+        _ => Ok((req.encode_to_vec(), "application/x-protobuf")),
     }
 }
 
diff --git a/opentelemetry-otlp/src/exporter/http/trace.rs b/opentelemetry-otlp/src/exporter/http/trace.rs
index b12f2fcef6..21de0881f9 100644
--- a/opentelemetry-otlp/src/exporter/http/trace.rs
+++ b/opentelemetry-otlp/src/exporter/http/trace.rs
@@ -79,23 +79,13 @@ fn build_body(spans: Vec<SpanData>) -> TraceResult<(Vec<u8>, &'static str)> {
     let req = ExportTraceServiceRequest {
         resource_spans: spans.into_iter().map(Into::into).collect(),
     };
-    let buf;
-    let ctype;
     match default_protocol() {
         #[cfg(feature = "http-json")]
         Protocol::HttpJson => match serde_json::to_string_pretty(&req) {
-            Ok(json) => {
-                buf = json.into();
-                ctype = "application/json";
-                Ok((buf, ctype))
-            }
+            Ok(json) => Ok((json.into(), "application/json")),
             Err(e) => Err(TraceError::from(e.to_string())),
         },
-        _ => {
-            buf = req.encode_to_vec();
-            ctype = "application/x-protobuf";
-            Ok((buf, ctype))
-        }
+        _ => Ok((req.encode_to_vec(), "application/x-protobuf")),
     }
 }
 

From 250fab497aabe5ef3d13c2a7da7d2deeab1fc8c5 Mon Sep 17 00:00:00 2001
From: Ramajeyam Gopalraj <ramgdev@gmail.com>
Date: Fri, 29 Mar 2024 17:13:04 -0400
Subject: [PATCH 19/22] remove duplicate line

---
 opentelemetry-otlp/src/exporter/http/metrics.rs | 1 -
 1 file changed, 1 deletion(-)

diff --git a/opentelemetry-otlp/src/exporter/http/metrics.rs b/opentelemetry-otlp/src/exporter/http/metrics.rs
index 528481e4bc..7886913f4d 100644
--- a/opentelemetry-otlp/src/exporter/http/metrics.rs
+++ b/opentelemetry-otlp/src/exporter/http/metrics.rs
@@ -59,7 +59,6 @@ fn build_body(metrics: &mut ResourceMetrics) -> Result<(Vec<u8>, &'static str)>
         (&*metrics).into();
 
     match default_protocol() {
-        #[cfg(feature = "http-json")]
         #[cfg(feature = "http-json")]
         Protocol::HttpJson => match serde_json::to_string_pretty(&req) {
             Ok(json) => Ok((json.into(), "application/json")),

From 67552f807800c8f85f47018d5f3a6cb490128d72 Mon Sep 17 00:00:00 2001
From: Ramji <ramgdev@users.noreply.github.com>
Date: Sun, 31 Mar 2024 20:24:15 -0400
Subject: [PATCH 20/22] Update opentelemetry-otlp/src/exporter/http/metrics.rs

Co-authored-by: Zhongyang Wu <zhongyang.wu@outlook.com>
---
 opentelemetry-otlp/src/exporter/http/metrics.rs | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/opentelemetry-otlp/src/exporter/http/metrics.rs b/opentelemetry-otlp/src/exporter/http/metrics.rs
index 7886913f4d..d3c2a424fc 100644
--- a/opentelemetry-otlp/src/exporter/http/metrics.rs
+++ b/opentelemetry-otlp/src/exporter/http/metrics.rs
@@ -71,6 +71,6 @@ fn build_body(metrics: &mut ResourceMetrics) -> Result<(Vec<u8>, &'static str)>
 #[cfg(not(any(feature = "http-proto", feature = "http-json")))]
 fn build_body(_metrics: &mut ResourceMetrics) -> Result<(Vec<u8>, &'static str)> {
     Err(MetricsError::Other(
-        "No http protocol configured. Enable one via `http-proto`".into(),
+        "No http protocol configured. Enable `http-proto` or `http-json`".into(),
     ))
 }

From 4ed5158dfad4096e84dc27aed38ed768f1c5a6c9 Mon Sep 17 00:00:00 2001
From: Ramajeyam Gopalraj <ramgdev@gmail.com>
Date: Sat, 20 Apr 2024 18:02:08 -0400
Subject: [PATCH 21/22] move build_body to otlphttpclient

---
 opentelemetry-otlp/src/exporter/http/logs.rs  | 30 +------
 .../src/exporter/http/metrics.rs              | 29 +------
 opentelemetry-otlp/src/exporter/http/mod.rs   | 82 ++++++++++++++++++-
 opentelemetry-otlp/src/exporter/http/trace.rs | 82 +------------------
 4 files changed, 82 insertions(+), 141 deletions(-)

diff --git a/opentelemetry-otlp/src/exporter/http/logs.rs b/opentelemetry-otlp/src/exporter/http/logs.rs
index 7d92a24fc5..1d8e177693 100644
--- a/opentelemetry-otlp/src/exporter/http/logs.rs
+++ b/opentelemetry-otlp/src/exporter/http/logs.rs
@@ -19,7 +19,7 @@ impl LogExporter for OtlpHttpClient {
                 _ => Err(LogError::Other("exporter is already shut down".into())),
             })?;
 
-        let (body, content_type) = build_body(batch)?;
+        let (body, content_type) = self.build_logs_export_body(batch)?;
         let mut request = http::Request::builder()
             .method(Method::POST)
             .uri(&self.collector_endpoint)
@@ -51,31 +51,3 @@ impl LogExporter for OtlpHttpClient {
         let _ = self.client.lock().map(|mut c| c.take());
     }
 }
-
-#[cfg(any(feature = "http-proto", feature = "http-json"))]
-fn build_body(logs: Vec<LogData>) -> LogResult<(Vec<u8>, &'static str)> {
-    use crate::exporter::default_protocol;
-    #[cfg(feature = "http-json")]
-    use crate::Protocol;
-    use opentelemetry_proto::tonic::collector::logs::v1::ExportLogsServiceRequest;
-    use prost::Message;
-
-    let req = ExportLogsServiceRequest {
-        resource_logs: logs.into_iter().map(Into::into).collect(),
-    };
-    match default_protocol() {
-        #[cfg(feature = "http-json")]
-        Protocol::HttpJson => match serde_json::to_string_pretty(&req) {
-            Ok(json) => Ok((json.into(), "application/json")),
-            Err(e) => Err(LogError::from(e.to_string())),
-        },
-        _ => Ok((req.encode_to_vec(), "application/x-protobuf")),
-    }
-}
-
-#[cfg(not(any(feature = "http-proto", feature = "http-json")))]
-fn build_body(logs: Vec<LogData>) -> LogResult<(Vec<u8>, &'static str)> {
-    Err(LogsError::Other(
-        "No http protocol configured. Enable one via `http-proto`".into(),
-    ))
-}
diff --git a/opentelemetry-otlp/src/exporter/http/metrics.rs b/opentelemetry-otlp/src/exporter/http/metrics.rs
index d3c2a424fc..8fcf1bc362 100644
--- a/opentelemetry-otlp/src/exporter/http/metrics.rs
+++ b/opentelemetry-otlp/src/exporter/http/metrics.rs
@@ -21,7 +21,7 @@ impl MetricsClient for OtlpHttpClient {
                 _ => Err(MetricsError::Other("exporter is already shut down".into())),
             })?;
 
-        let (body, content_type) = build_body(metrics)?;
+        let (body, content_type) = self.build_metrics_export_body(metrics)?;
         let mut request = http::Request::builder()
             .method(Method::POST)
             .uri(&self.collector_endpoint)
@@ -47,30 +47,3 @@ impl MetricsClient for OtlpHttpClient {
         Ok(())
     }
 }
-
-#[cfg(any(feature = "http-proto", feature = "http-json"))]
-fn build_body(metrics: &mut ResourceMetrics) -> Result<(Vec<u8>, &'static str)> {
-    use crate::exporter::default_protocol;
-    #[cfg(feature = "http-json")]
-    use crate::Protocol;
-    use prost::Message;
-
-    let req: opentelemetry_proto::tonic::collector::metrics::v1::ExportMetricsServiceRequest =
-        (&*metrics).into();
-
-    match default_protocol() {
-        #[cfg(feature = "http-json")]
-        Protocol::HttpJson => match serde_json::to_string_pretty(&req) {
-            Ok(json) => Ok((json.into(), "application/json")),
-            Err(e) => Err(MetricsError::Other(e.to_string())),
-        },
-        _ => Ok((req.encode_to_vec(), "application/x-protobuf")),
-    }
-}
-
-#[cfg(not(any(feature = "http-proto", feature = "http-json")))]
-fn build_body(_metrics: &mut ResourceMetrics) -> Result<(Vec<u8>, &'static str)> {
-    Err(MetricsError::Other(
-        "No http protocol configured. Enable `http-proto` or `http-json`".into(),
-    ))
-}
diff --git a/opentelemetry-otlp/src/exporter/http/mod.rs b/opentelemetry-otlp/src/exporter/http/mod.rs
index b8659f9a62..4cfc002486 100644
--- a/opentelemetry-otlp/src/exporter/http/mod.rs
+++ b/opentelemetry-otlp/src/exporter/http/mod.rs
@@ -1,17 +1,23 @@
+use super::{default_headers, default_protocol, parse_header_string};
 use crate::{
-    ExportConfig, OTEL_EXPORTER_OTLP_ENDPOINT, OTEL_EXPORTER_OTLP_HEADERS,
+    ExportConfig, Protocol, OTEL_EXPORTER_OTLP_ENDPOINT, OTEL_EXPORTER_OTLP_HEADERS,
     OTEL_EXPORTER_OTLP_TIMEOUT,
 };
 use http::{HeaderName, HeaderValue, Uri};
 use opentelemetry_http::HttpClient;
+#[cfg(feature = "logs")]
+use opentelemetry_sdk::export::logs::LogData;
+#[cfg(feature = "trace")]
+use opentelemetry_sdk::export::trace::SpanData;
+#[cfg(feature = "metrics")]
+use opentelemetry_sdk::metrics::data::ResourceMetrics;
+use prost::Message;
 use std::collections::HashMap;
 use std::env;
 use std::str::FromStr;
 use std::sync::{Arc, Mutex};
 use std::time::Duration;
 
-use super::{default_headers, default_protocol, parse_header_string};
-
 #[cfg(feature = "metrics")]
 mod metrics;
 
@@ -181,7 +187,13 @@ impl HttpExporterBuilder {
             add_header_from_string(&input, &mut headers);
         }
 
-        Ok(OtlpHttpClient::new(http_client, endpoint, headers, timeout))
+        Ok(OtlpHttpClient::new(
+            http_client,
+            endpoint,
+            headers,
+            self.exporter_config.protocol,
+            timeout,
+        ))
     }
 
     /// Create a log exporter with the current configuration
@@ -254,6 +266,7 @@ struct OtlpHttpClient {
     client: Mutex<Option<Arc<dyn HttpClient>>>,
     collector_endpoint: Uri,
     headers: HashMap<HeaderName, HeaderValue>,
+    protocol: Protocol,
     _timeout: Duration,
 }
 
@@ -263,15 +276,76 @@ impl OtlpHttpClient {
         client: Arc<dyn HttpClient>,
         collector_endpoint: Uri,
         headers: HashMap<HeaderName, HeaderValue>,
+        protocol: Protocol,
         timeout: Duration,
     ) -> Self {
         OtlpHttpClient {
             client: Mutex::new(Some(client)),
             collector_endpoint,
             headers,
+            protocol,
             _timeout: timeout,
         }
     }
+
+    #[cfg(feature = "trace")]
+    fn build_trace_export_body(
+        &self,
+        spans: Vec<SpanData>,
+    ) -> opentelemetry::trace::TraceResult<(Vec<u8>, &'static str)> {
+        use opentelemetry_proto::tonic::collector::trace::v1::ExportTraceServiceRequest;
+
+        let req = ExportTraceServiceRequest {
+            resource_spans: spans.into_iter().map(Into::into).collect(),
+        };
+        match self.protocol {
+            #[cfg(feature = "http-json")]
+            Protocol::HttpJson => match serde_json::to_string_pretty(&req) {
+                Ok(json) => Ok((json.into(), "application/json")),
+                Err(e) => Err(opentelemetry::trace::TraceError::from(e.to_string())),
+            },
+            _ => Ok((req.encode_to_vec(), "application/x-protobuf")),
+        }
+    }
+
+    #[cfg(feature = "logs")]
+    fn build_logs_export_body(
+        &self,
+        logs: Vec<LogData>,
+    ) -> opentelemetry::logs::LogResult<(Vec<u8>, &'static str)> {
+        use opentelemetry_proto::tonic::collector::logs::v1::ExportLogsServiceRequest;
+
+        let req = ExportLogsServiceRequest {
+            resource_logs: logs.into_iter().map(Into::into).collect(),
+        };
+        match self.protocol {
+            #[cfg(feature = "http-json")]
+            Protocol::HttpJson => match serde_json::to_string_pretty(&req) {
+                Ok(json) => Ok((json.into(), "application/json")),
+                Err(e) => Err(opentelemetry::logs::LogError::from(e.to_string())),
+            },
+            _ => Ok((req.encode_to_vec(), "application/x-protobuf")),
+        }
+    }
+
+    #[cfg(feature = "metrics")]
+    fn build_metrics_export_body(
+        &self,
+        metrics: &mut ResourceMetrics,
+    ) -> opentelemetry::metrics::Result<(Vec<u8>, &'static str)> {
+        use opentelemetry_proto::tonic::collector::metrics::v1::ExportMetricsServiceRequest;
+
+        let req: ExportMetricsServiceRequest = (&*metrics).into();
+
+        match self.protocol {
+            #[cfg(feature = "http-json")]
+            Protocol::HttpJson => match serde_json::to_string_pretty(&req) {
+                Ok(json) => Ok((json.into(), "application/json")),
+                Err(e) => Err(opentelemetry::metrics::MetricsError::Other(e.to_string())),
+            },
+            _ => Ok((req.encode_to_vec(), "application/x-protobuf")),
+        }
+    }
 }
 
 fn build_endpoint_uri(endpoint: &str, path: &str) -> Result<Uri, crate::Error> {
diff --git a/opentelemetry-otlp/src/exporter/http/trace.rs b/opentelemetry-otlp/src/exporter/http/trace.rs
index 21de0881f9..8e272c93cf 100644
--- a/opentelemetry-otlp/src/exporter/http/trace.rs
+++ b/opentelemetry-otlp/src/exporter/http/trace.rs
@@ -2,7 +2,7 @@ use std::sync::Arc;
 
 use futures_core::future::BoxFuture;
 use http::{header::CONTENT_TYPE, Method};
-use opentelemetry::trace::{TraceError, TraceResult};
+use opentelemetry::trace::TraceError;
 use opentelemetry_sdk::export::trace::{ExportResult, SpanData, SpanExporter};
 
 use super::OtlpHttpClient;
@@ -21,7 +21,7 @@ impl SpanExporter for OtlpHttpClient {
             Err(err) => return Box::pin(std::future::ready(Err(err))),
         };
 
-        let (body, content_type) = match build_body(batch) {
+        let (body, content_type) = match self.build_trace_export_body(batch) {
             Ok(body) => body,
             Err(e) => return Box::pin(std::future::ready(Err(e))),
         };
@@ -67,81 +67,3 @@ impl SpanExporter for OtlpHttpClient {
         let _ = self.client.lock().map(|mut c| c.take());
     }
 }
-
-#[cfg(any(feature = "http-proto", feature = "http-json"))]
-fn build_body(spans: Vec<SpanData>) -> TraceResult<(Vec<u8>, &'static str)> {
-    use crate::exporter::default_protocol;
-    #[cfg(feature = "http-json")]
-    use crate::Protocol;
-    use opentelemetry_proto::tonic::collector::trace::v1::ExportTraceServiceRequest;
-    use prost::Message;
-
-    let req = ExportTraceServiceRequest {
-        resource_spans: spans.into_iter().map(Into::into).collect(),
-    };
-    match default_protocol() {
-        #[cfg(feature = "http-json")]
-        Protocol::HttpJson => match serde_json::to_string_pretty(&req) {
-            Ok(json) => Ok((json.into(), "application/json")),
-            Err(e) => Err(TraceError::from(e.to_string())),
-        },
-        _ => Ok((req.encode_to_vec(), "application/x-protobuf")),
-    }
-}
-
-#[cfg(not(any(feature = "http-proto", feature = "http-json")))]
-fn build_body(spans: Vec<SpanData>) -> TraceResult<(Vec<u8>, &'static str)> {
-    Err(TraceError::Other(
-        "No http protocol configured. Enable one via `http-proto` or `http-json`".into(),
-    ))
-}
-
-#[cfg(any(feature = "http-proto", feature = "http-json"))]
-mod tests {
-    #[test]
-    fn test_build_body() {
-        use crate::exporter::http::trace::build_body;
-        use opentelemetry::trace::{
-            SpanContext, SpanId, SpanKind, Status, TraceFlags, TraceId, TraceState,
-        };
-        use opentelemetry_sdk::export::trace::SpanData;
-        use opentelemetry_sdk::trace::{SpanEvents, SpanLinks};
-        use opentelemetry_sdk::Resource;
-        use std::{borrow::Cow, time::SystemTime};
-
-        let span_data = (0..5)
-            .map(|_| SpanData {
-                span_context: SpanContext::new(
-                    TraceId::from_u128(12),
-                    SpanId::from_u64(12),
-                    TraceFlags::default(),
-                    false,
-                    TraceState::default(),
-                ),
-                parent_span_id: SpanId::from_u64(12),
-                span_kind: SpanKind::Client,
-                name: Default::default(),
-                start_time: SystemTime::now(),
-                end_time: SystemTime::now(),
-                attributes: Vec::new(),
-                dropped_attributes_count: 0,
-                events: SpanEvents::default(),
-                links: SpanLinks::default(),
-                status: Status::Unset,
-                resource: Cow::Owned(Resource::empty()),
-                instrumentation_lib: Default::default(),
-            })
-            .collect::<Vec<SpanData>>();
-
-        let result = build_body(span_data).unwrap();
-        match crate::exporter::default_protocol() {
-            #[cfg(feature = "http-json")]
-            crate::Protocol::HttpJson => {
-                assert_eq!(result.1, "application/json")
-            }
-            _ => {
-                assert_eq!(result.1, "application/x-protobuf")
-            }
-        };
-    }
-}

From ebc3cc3178c5e15d1e51c1737fc88f4b9b0970aa Mon Sep 17 00:00:00 2001
From: Ramajeyam Gopalraj <ramgdev@gmail.com>
Date: Sat, 20 Apr 2024 18:42:49 -0400
Subject: [PATCH 22/22] allow builder to accept protocol

---
 opentelemetry-otlp/Cargo.toml               | 4 ++--
 opentelemetry-otlp/src/exporter/http/mod.rs | 6 ++++++
 2 files changed, 8 insertions(+), 2 deletions(-)

diff --git a/opentelemetry-otlp/Cargo.toml b/opentelemetry-otlp/Cargo.toml
index d1fcd2025f..29787ed95b 100644
--- a/opentelemetry-otlp/Cargo.toml
+++ b/opentelemetry-otlp/Cargo.toml
@@ -71,11 +71,11 @@ tls-roots = ["tls", "tonic/tls-roots"]
 
 # http binary
 http-proto = ["prost", "opentelemetry-http", "opentelemetry-proto/gen-tonic-messages", "http", "trace", "metrics"]
+# http json
+http-json = ["serde_json", "prost", "opentelemetry-http", "opentelemetry-proto/gen-tonic-messages", "opentelemetry-proto/with-serde", "http", "trace", "metrics"]
 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", "opentelemetry-proto/with-serde", "http", "trace", "metrics"]
 
 # test
 integration-testing = ["tonic", "prost", "tokio/full", "trace"]
diff --git a/opentelemetry-otlp/src/exporter/http/mod.rs b/opentelemetry-otlp/src/exporter/http/mod.rs
index 4cfc002486..884971e028 100644
--- a/opentelemetry-otlp/src/exporter/http/mod.rs
+++ b/opentelemetry-otlp/src/exporter/http/mod.rs
@@ -116,6 +116,12 @@ impl Default for HttpExporterBuilder {
 }
 
 impl HttpExporterBuilder {
+    /// Specify the OTLP protocol to be used by the exporter
+    pub fn with_protocol(mut self, protocol: Protocol) -> Self {
+        self.exporter_config.protocol = protocol;
+        self
+    }
+
     /// Assign client implementation
     pub fn with_http_client<T: HttpClient + 'static>(mut self, client: T) -> Self {
         self.http_config.client = Some(Arc::new(client));