Minor fix to OTLP doc and integration test (#1758)

Co-authored-by: Zhongyang Wu <[email protected]>

opentelemetry-otlp/src/lib.rs

@@ -24,23 +24,25 @@
 //! Then install a new pipeline with the recommended defaults to start exporting
 //! telemetry. You will have to build a OTLP exporter first.
 //!
-//! Tracing and metrics pipelines can be started with `new_pipeline().tracing()` and
-//! `new_pipeline().metrics()` respectively.
+//! Exporting pipelines can be started with `new_pipeline().tracing()` and
+//! `new_pipeline().metrics()`, and `new_pipeline().logging()` respectively for
+//! traces, metrics and logs.
 //!
 //! ```no_run
 //! # #[cfg(all(feature = "trace", feature = "grpc-tonic"))]
 //! # {
+//! use opentelemetry::global;
 //! use opentelemetry::trace::Tracer;
 //!
 //! fn main() -> Result<(), Box<dyn std::error::Error + Send + Sync + 'static>> {
 //!     // First, create a OTLP exporter builder. Configure it as you need.
 //!     let otlp_exporter = opentelemetry_otlp::new_exporter().tonic();
 //!     // Then pass it into pipeline builder
-//!     let tracer = opentelemetry_otlp::new_pipeline()
+//!     let _ = opentelemetry_otlp::new_pipeline()
 //!         .tracing()
 //!         .with_exporter(otlp_exporter)
 //!         .install_simple()?;
-//!
+//!     let tracer = global::tracer("my_tracer");
 //!     tracer.in_span("doing_work", |cx| {
 //!         // Traced app logic here...
 //!     });

opentelemetry-otlp/tests/integration_test/Cargo.toml

@@ -15,3 +15,4 @@ opentelemetry-proto = { path = "../../../opentelemetry-proto", features = ["gen-
 tokio = { version = "1.0", features = ["full"] }
 serde_json = "1"
 testcontainers = "0.15.0"
+# env_logger = "0.11.3" // uncomment if needed for local debugging.

opentelemetry-otlp/tests/integration_test/tests/integration_tests.rs

@@ -52,6 +52,11 @@ impl TestSuite {
 #[tokio::test(flavor = "multi_thread", worker_threads = 4)]
 #[ignore] // skip when running unit test
 async fn integration_tests() {
+    // Uncomment to see logs from testcontainers
+    // env_logger::init();
+    // Run locally using the below command
+    // cargo test -- --ignored --nocapture
+
     let test_suites = [TestSuite::new("traces.json")];
 
     let mut collector_image = Collector::default();