Fix invoke span by specifying a minimum version of tracing

.rustfmt.toml

@@ -1,6 +1,6 @@
-edition = "2018"
+edition = "2021"
 # imports_granularity is unstable
 # # https://github.com/rust-lang/rustfmt/blob/master/Configurations.md#merge_imports
 # imports_granularity = "Crate"
 # https://github.com/rust-lang/rustfmt/blob/master/Configurations.md#max_width
-max_width = 120
+max_width = 120

lambda-runtime/Cargo.toml

@@ -18,16 +18,26 @@ default = ["simulated"]
 simulated = []
 
 [dependencies]
-tokio = { version = "1.0", features = ["macros", "io-util", "sync", "rt-multi-thread"] }
+tokio = { version = "1.0", features = [
+    "macros",
+    "io-util",
+    "sync",
+    "rt-multi-thread",
+] }
 # Hyper requires the `server` feature to work on nightly
-hyper = { version = "0.14.20", features = ["http1", "client", "stream", "server"] }
+hyper = { version = "0.14.20", features = [
+    "http1",
+    "client",
+    "stream",
+    "server",
+] }
 futures = "0.3"
 serde = { version = "1", features = ["derive"] }
 serde_json = "^1"
 bytes = "1.0"
 http = "0.2"
 async-stream = "0.3"
-tracing = { version = "0.1", features = ["log"] }
+tracing = { version = "0.1.37", features = ["log"] }
 tower = { version = "0.4", features = ["util"] }
 tokio-stream = "0.1.2"
 lambda_runtime_api_client = { version = "0.7", path = "../lambda-runtime-api-client" }

lambda-runtime/src/lib.rs

@@ -124,19 +124,15 @@ where
             let ctx: Context = ctx.with_config(config);
             let request_id = &ctx.request_id.clone();
 
-            let xray_trace_id = &ctx.xray_trace_id.clone();
-            match xray_trace_id {
-                Some(trace_id) => env::set_var("_X_AMZN_TRACE_ID", trace_id),
-                None => env::remove_var("_X_AMZN_TRACE_ID"),
-            }
-            let request_span = match xray_trace_id {
-                Some(trace_id) => tracing::span!(
-                    tracing::Level::INFO,
-                    "Lambda runtime invoke",
-                    requestId = request_id,
-                    xrayTraceId = trace_id
-                ),
-                None => tracing::span!(tracing::Level::INFO, "Lambda runtime invoke", requestId = request_id),
+            let request_span = match &ctx.xray_trace_id {
+                Some(trace_id) => {
+                    env::set_var("_X_AMZN_TRACE_ID", trace_id);
+                    tracing::info_span!("Lambda runtime invoke", requestId = request_id, xrayTraceId = trace_id)
+                }
+                None => {
+                    env::remove_var("_X_AMZN_TRACE_ID");
+                    tracing::info_span!("Lambda runtime invoke", requestId = request_id)
+                }
             };
 
             // Group the handling in one future and instrument it with the span