feat: implement additional metric tags for trace stats

LICENSE-3rdparty.csv

@@ -30,9 +30,11 @@ camino,https://github.com/camino-rs/camino,MIT OR Apache-2.0,"Without Boats <sao
 cargo-platform,https://github.com/rust-lang/cargo,MIT OR Apache-2.0,The cargo-platform Authors
 cargo_metadata,https://github.com/oli-obk/cargo_metadata,MIT,Oliver Schneider <git-spam-no-reply9815368754983@oli-obk.de>
 cc,https://github.com/rust-lang/cc-rs,MIT OR Apache-2.0,Alex Crichton <alex@alexcrichton.com>
+cesu8,https://github.com/emk/cesu8-rs,Apache-2.0 OR MIT,Eric Kidd <git@randomhacks.net>
 cexpr,https://github.com/jethrogb/rust-cexpr,Apache-2.0 OR MIT,Jethro Beekman <jethro@jbeekman.nl>
 cfg-if,https://github.com/rust-lang/cfg-if,MIT OR Apache-2.0,Alex Crichton <alex@alexcrichton.com>
 clang-sys,https://github.com/KyleMayes/clang-sys,Apache-2.0,Kyle Mayes <kyle@mayeses.com>
+combine,https://github.com/Marwes/combine,MIT,Markus Westerlind <marwes91@gmail.com>
 concurrent-queue,https://github.com/smol-rs/concurrent-queue,Apache-2.0 OR MIT,"Stjepan Glavina <stjepang@gmail.com>, Taiki Endo <te316e89@gmail.com>, John Nunley <dev@notgull.net>"
 const_format,https://github.com/rodrimati1992/const_format_crates,Zlib,rodrimati1992 <rodrimatt1985@gmail.com>
 const_format_proc_macros,https://github.com/rodrimati1992/const_format_crates,Zlib,rodrimati1992 <rodrimatt1985@gmail.com>
@@ -112,6 +114,10 @@ ipnet,https://github.com/krisprice/ipnet,MIT OR Apache-2.0,Kris Price <kris@kris
 iri-string,https://github.com/lo48576/iri-string,MIT OR Apache-2.0,YOSHIOKA Takuma <nop_thread@nops.red>
 itertools,https://github.com/rust-itertools/itertools,MIT OR Apache-2.0,bluss
 itoa,https://github.com/dtolnay/itoa,MIT OR Apache-2.0,David Tolnay <dtolnay@gmail.com>
+jni,https://github.com/jni-rs/jni-rs,MIT OR Apache-2.0,Josh Chase <josh@prevoty.com>
+jni-sys,https://github.com/jni-rs/jni-sys,MIT OR Apache-2.0,Steven Fackler <sfackler@gmail.com>
+jni-sys,https://github.com/jni-rs/jni-sys,MIT OR Apache-2.0,"Steven Fackler <sfackler@gmail.com>, Robert Bragg <robert@sixbynine.org>"
+jni-sys-macros,https://github.com/jni-rs/jni-sys,MIT OR Apache-2.0,Robert Bragg <robert@sixbynine.org>
 jobserver,https://github.com/rust-lang/jobserver-rs,MIT OR Apache-2.0,Alex Crichton <alex@alexcrichton.com>
 js-sys,https://github.com/wasm-bindgen/wasm-bindgen/tree/master/crates/js-sys,MIT OR Apache-2.0,The wasm-bindgen Developers
 lazy_static,https://github.com/rust-lang-nursery/lazy-static.rs,MIT OR Apache-2.0,Marvin Löbel <loebel.marvin@gmail.com>
@@ -209,17 +215,21 @@ rustix,https://github.com/bytecodealliance/rustix,Apache-2.0 WITH LLVM-exception
 rustls,https://github.com/rustls/rustls,Apache-2.0 OR ISC OR MIT,The rustls Authors
 rustls-native-certs,https://github.com/rustls/rustls-native-certs,Apache-2.0 OR ISC OR MIT,The rustls-native-certs Authors
 rustls-pki-types,https://github.com/rustls/pki-types,MIT OR Apache-2.0,The rustls-pki-types Authors
+rustls-platform-verifier,https://github.com/rustls/rustls-platform-verifier,MIT OR Apache-2.0,The rustls-platform-verifier Authors
+rustls-platform-verifier-android,https://github.com/rustls/rustls-platform-verifier,MIT OR Apache-2.0,The rustls-platform-verifier-android Authors
 rustls-webpki,https://github.com/rustls/webpki,ISC,The rustls-webpki Authors
 rustversion,https://github.com/dtolnay/rustversion,MIT OR Apache-2.0,David Tolnay <dtolnay@gmail.com>
 rusty-fork,https://github.com/altsysrq/rusty-fork,MIT OR Apache-2.0,Jason Lingle
 ryu,https://github.com/dtolnay/ryu,Apache-2.0 OR BSL-1.0,David Tolnay <dtolnay@gmail.com>
+same-file,https://github.com/BurntSushi/same-file,Unlicense OR MIT,Andrew Gallant <jamslam@gmail.com>
 schannel,https://github.com/steffengy/schannel-rs,MIT,"Steven Fackler <sfackler@gmail.com>, Steffen Butzer <steffen.butzer@outlook.com>"
 scopeguard,https://github.com/bluss/scopeguard,MIT OR Apache-2.0,bluss
 security-framework,https://github.com/kornelski/rust-security-framework,MIT OR Apache-2.0,"Steven Fackler <sfackler@gmail.com>, Kornel <kornel@geekhood.net>"
 security-framework-sys,https://github.com/kornelski/rust-security-framework,MIT OR Apache-2.0,"Steven Fackler <sfackler@gmail.com>, Kornel <kornel@geekhood.net>"
 semver,https://github.com/dtolnay/semver,MIT OR Apache-2.0,David Tolnay <dtolnay@gmail.com>
 serde,https://github.com/serde-rs/serde,MIT OR Apache-2.0,"Erick Tryzelaar <erick.tryzelaar@gmail.com>, David Tolnay <dtolnay@gmail.com>"
 serde-aux,https://github.com/iddm/serde-aux,MIT,Victor Polevoy <maintainer@vpolevoy.com>
+serde-transcode,https://github.com/sfackler/serde-transcode,MIT OR Apache-2.0,Steven Fackler <sfackler@palantir.com>
 serde-value,https://github.com/arcnmx/serde-value,MIT,arcnmx
 serde_bytes,https://github.com/serde-rs/bytes,MIT OR Apache-2.0,David Tolnay <dtolnay@gmail.com>
 serde_core,https://github.com/serde-rs/serde,MIT OR Apache-2.0,"Erick Tryzelaar <erick.tryzelaar@gmail.com>, David Tolnay <dtolnay@gmail.com>"
@@ -249,6 +259,7 @@ synstructure,https://github.com/mystor/synstructure,MIT,Nika Layzell <nika@thela
 sys-info,https://github.com/FillZpp/sys-info-rs,MIT,Siyu Wang <FillZpp.pub@gmail.com>
 tabwriter,https://github.com/BurntSushi/tabwriter,Unlicense OR MIT,Andrew Gallant <jamslam@gmail.com>
 tempfile,https://github.com/Stebalien/tempfile,MIT OR Apache-2.0,"Steven Allen <steven@stebalien.com>, The Rust Project Developers, Ashley Mannix <ashleymannix@live.com.au>, Jason White <me@jasonwhite.io>"
+thin-vec,https://github.com/mozilla/thin-vec,MIT OR Apache-2.0,Aria Beingessner <a.beingessner@gmail.com>
 thiserror,https://github.com/dtolnay/thiserror,MIT OR Apache-2.0,David Tolnay <dtolnay@gmail.com>
 thiserror-impl,https://github.com/dtolnay/thiserror,MIT OR Apache-2.0,David Tolnay <dtolnay@gmail.com>
 thread_local,https://github.com/Amanieu/thread_local-rs,MIT OR Apache-2.0,Amanieu d'Antras <amanieu@gmail.com>
@@ -301,8 +312,10 @@ wasm-metadata,https://github.com/bytecodealliance/wasm-tools/tree/main/crates/wa
 wasmparser,https://github.com/bytecodealliance/wasm-tools/tree/main/crates/wasmparser,Apache-2.0 WITH LLVM-exception OR Apache-2.0 OR MIT,Yury Delendik <ydelendik@mozilla.com>
 web-sys,https://github.com/wasm-bindgen/wasm-bindgen/tree/master/crates/web-sys,MIT OR Apache-2.0,The wasm-bindgen Developers
 web-time,https://github.com/daxpedda/web-time,MIT OR Apache-2.0,The web-time Authors
+webpki-root-certs,https://github.com/rustls/webpki-roots,CDLA-Permissive-2.0,The webpki-root-certs Authors
 webpki-roots,https://github.com/rustls/webpki-roots,CDLA-Permissive-2.0,The webpki-roots Authors
 which,https://github.com/harryfei/which-rs,MIT,Harry Fei <tiziyuanfang@gmail.com>
+winapi-util,https://github.com/BurntSushi/winapi-util,Unlicense OR MIT,Andrew Gallant <jamslam@gmail.com>
 windows,https://github.com/microsoft/windows-rs,MIT OR Apache-2.0,Microsoft
 windows-link,https://github.com/microsoft/windows-rs,MIT OR Apache-2.0,The windows-link Authors
 windows-sys,https://github.com/microsoft/windows-rs,MIT OR Apache-2.0,Microsoft

crates/datadog-agent-config/Cargo.toml

@@ -6,8 +6,8 @@ license.workspace = true
 
 [dependencies]
 figment = { version = "0.10", default-features = false, features = ["yaml", "env"] }
-libdd-trace-obfuscation = { git = "https://github.com/DataDog/libdatadog", rev = "a820699426f28cbabb3a74d87c7309d030b52e7c", default-features = false }
-libdd-trace-utils = { git = "https://github.com/DataDog/libdatadog", rev = "a820699426f28cbabb3a74d87c7309d030b52e7c", default-features = false }
+libdd-trace-obfuscation = { git = "https://github.com/DataDog/libdatadog", rev = "def0a56d1686661e812c6fedb5902ad1cd28d8fe", default-features = false }
+libdd-trace-utils = { git = "https://github.com/DataDog/libdatadog", rev = "def0a56d1686661e812c6fedb5902ad1cd28d8fe", default-features = false }
 log = { version = "0.4", default-features = false }
 serde = { version = "1.0", default-features = false, features = ["derive"] }
 serde-aux = { version = "4.7", default-features = false }

crates/datadog-metrics-collector/Cargo.toml

@@ -8,7 +8,7 @@ description = "Collector to read, compute, and submit enhanced metrics in Server
 [dependencies]
 dogstatsd = { path = "../dogstatsd", default-features = true }
 tracing = { version = "0.1", default-features = false }
-libdd-common = { git = "https://github.com/DataDog/libdatadog", rev = "a820699426f28cbabb3a74d87c7309d030b52e7c", default-features = false }
+libdd-common = { git = "https://github.com/DataDog/libdatadog", rev = "def0a56d1686661e812c6fedb5902ad1cd28d8fe", default-features = false }
 
 [target.'cfg(windows)'.dependencies]
 windows-sys = { version = "0.61", features = ["Win32_System_JobObjects"], optional = true, default-features = false }

crates/datadog-serverless-compat/Cargo.toml

@@ -14,7 +14,7 @@ windows-enhanced-metrics = ["datadog-metrics-collector/windows-enhanced-metrics"
 datadog-logs-agent = { path = "../datadog-logs-agent" }
 datadog-metrics-collector = { path = "../datadog-metrics-collector" }
 datadog-trace-agent = { path = "../datadog-trace-agent" }
-libdd-trace-utils = { git = "https://github.com/DataDog/libdatadog", rev = "a820699426f28cbabb3a74d87c7309d030b52e7c" }
+libdd-trace-utils = { git = "https://github.com/DataDog/libdatadog", rev = "def0a56d1686661e812c6fedb5902ad1cd28d8fe" }
 datadog-fips = { path = "../datadog-fips", default-features = false }
 dogstatsd = { path = "../dogstatsd", default-features = true }
 reqwest = { version = "0.12.4", default-features = false }

crates/datadog-trace-agent/Cargo.toml

@@ -25,16 +25,16 @@ tracing = { version = "0.1", default-features = false }
 serde = { version = "1.0.145", features = ["derive"] }
 serde_json = "1.0"
 thiserror = { version = "1.0.58", default-features = false }
-libdd-capabilities = { git = "https://github.com/DataDog/libdatadog", rev = "a820699426f28cbabb3a74d87c7309d030b52e7c" }
-libdd-capabilities-impl = { git = "https://github.com/DataDog/libdatadog", rev = "a820699426f28cbabb3a74d87c7309d030b52e7c" }
-libdd-common = { git = "https://github.com/DataDog/libdatadog", rev = "a820699426f28cbabb3a74d87c7309d030b52e7c" }
-libdd-library-config = { git = "https://github.com/DataDog/libdatadog", rev = "a820699426f28cbabb3a74d87c7309d030b52e7c" }
-libdd-trace-protobuf = { git = "https://github.com/DataDog/libdatadog", rev = "a820699426f28cbabb3a74d87c7309d030b52e7c" }
-libdd-trace-stats = { git = "https://github.com/DataDog/libdatadog", rev = "a820699426f28cbabb3a74d87c7309d030b52e7c" }
-libdd-trace-utils = { git = "https://github.com/DataDog/libdatadog", rev = "a820699426f28cbabb3a74d87c7309d030b52e7c", features = [
+libdd-capabilities = { git = "https://github.com/DataDog/libdatadog", rev = "def0a56d1686661e812c6fedb5902ad1cd28d8fe" }
+libdd-capabilities-impl = { git = "https://github.com/DataDog/libdatadog", rev = "def0a56d1686661e812c6fedb5902ad1cd28d8fe" }
+libdd-common = { git = "https://github.com/DataDog/libdatadog", rev = "def0a56d1686661e812c6fedb5902ad1cd28d8fe" }
+libdd-library-config = { git = "https://github.com/DataDog/libdatadog", rev = "def0a56d1686661e812c6fedb5902ad1cd28d8fe" }
+libdd-trace-protobuf = { git = "https://github.com/DataDog/libdatadog", rev = "def0a56d1686661e812c6fedb5902ad1cd28d8fe" }
+libdd-trace-stats = { git = "https://github.com/DataDog/libdatadog", rev = "def0a56d1686661e812c6fedb5902ad1cd28d8fe" }
+libdd-trace-utils = { git = "https://github.com/DataDog/libdatadog", rev = "def0a56d1686661e812c6fedb5902ad1cd28d8fe", features = [
     "mini_agent",
 ] }
-libdd-trace-obfuscation = { git = "https://github.com/DataDog/libdatadog", rev = "a820699426f28cbabb3a74d87c7309d030b52e7c" }
+libdd-trace-obfuscation = { git = "https://github.com/DataDog/libdatadog", rev = "def0a56d1686661e812c6fedb5902ad1cd28d8fe" }
 datadog-fips = { path = "../datadog-fips" }
 reqwest = { version = "0.12.23", features = [
     "json",
@@ -49,6 +49,6 @@ serial_test = "2.0.0"
 duplicate = "2.0.1"
 temp-env = "0.3.6"
 tempfile = "3.3.0"
-libdd-trace-utils = { git = "https://github.com/DataDog/libdatadog", rev = "a820699426f28cbabb3a74d87c7309d030b52e7c", features = [
+libdd-trace-utils = { git = "https://github.com/DataDog/libdatadog", rev = "def0a56d1686661e812c6fedb5902ad1cd28d8fe", features = [
     "test-utils",
 ] }

crates/datadog-trace-agent/src/config.rs

@@ -115,6 +115,14 @@ pub struct Config {
     pub proxy_url: Option<String>,
     pub env: String,
     pub peer_tags: Vec<String>,
+    /// Gates additional_metric_tags and related config.
+    pub experimental_features_enabled: bool,
+    /// Tag keys extracted from spans and used as additional aggregation dimensions in stats.
+    /// Only populated when experimental_features_enabled is true.
+    pub additional_metric_tags: Vec<String>,
+    /// Configures the per-bucket cardinality limit for additional_metric_tags stat entries.
+    /// Only populated when experimental_features_enabled is true.
+    pub additional_metric_tags_cardinality_limit: Option<usize>,
     /// Whether the agent should compute trace stats
     pub agent_stats_computation_enabled: bool,
 }
@@ -216,6 +224,10 @@ impl Config {
             Tags::new()
         };
 
+        let experimental_features_enabled = env::var("DD_TRACE_EXPERIMENTAL_FEATURES_ENABLED")
+            .map(|val| val.to_lowercase() == "true")
+            .unwrap_or(false);
+
         #[allow(clippy::unwrap_used)]
         Ok(Config {
             app_name: Some(app_name),
@@ -262,6 +274,30 @@ impl Config {
             tags,
             env: env::var("DD_ENV").unwrap_or_else(|_| "none".to_string()),
             peer_tags: peer_tag_keys()?,
+            experimental_features_enabled,
+            additional_metric_tags: if experimental_features_enabled {
+                env::var("DD_TRACE_STATS_ADDITIONAL_TAGS")
+                    .ok()
+                    .filter(|s| !s.is_empty())
+                    .map(|s| {
+                        s.split(',')
+                            .map(str::trim)
+                            .filter(|s| !s.is_empty())
+                            .map(str::to_owned)
+                            .collect()
+                    })
+                    .unwrap_or_default()
+            } else {
+                vec![]
+            },
+            additional_metric_tags_cardinality_limit: if experimental_features_enabled {
+                env::var("DD_TRACE_STATS_ADDITIONAL_TAGS_CARDINALITY_LIMIT")
+                    .ok()
+                    .and_then(|s| s.trim().parse::<usize>().ok())
+                    .filter(|&n| n > 0)
+            } else {
+                None
+            },
             agent_stats_computation_enabled: env::var("DD_AGENT_STATS_COMPUTATION_ENABLED")
                 .map(|val| val.to_lowercase() == "true")
                 .unwrap_or(false),
@@ -745,6 +781,53 @@ mod tests {
             },
         );
     }
+
+    #[test]
+    #[serial]
+    fn test_additional_metric_tags_gated_by_experimental_flag() {
+        let base_vars = [
+            ("DD_API_KEY", Some("_not_a_real_key_")),
+            ("FUNCTIONS_EXTENSION_VERSION", Some("~4")),
+            ("FUNCTIONS_WORKER_RUNTIME", Some("dotnet")),
+            ("WEBSITE_SITE_NAME", Some("my-azure-function")),
+            ("DD_TRACE_STATS_ADDITIONAL_TAGS", Some("region,tenant_id")),
+            (
+                "DD_TRACE_STATS_ADDITIONAL_TAGS_CARDINALITY_LIMIT",
+                Some("50"),
+            ),
+        ];
+
+        temp_env::with_vars(
+            base_vars
+                .iter()
+                .cloned()
+                .chain([("DD_TRACE_EXPERIMENTAL_FEATURES_ENABLED", Some("false"))])
+                .collect::<Vec<_>>(),
+            || {
+                let config = config::Config::new().unwrap();
+                assert!(!config.experimental_features_enabled);
+                assert!(config.additional_metric_tags.is_empty());
+                assert_eq!(config.additional_metric_tags_cardinality_limit, None);
+            },
+        );
+
+        temp_env::with_vars(
+            base_vars
+                .iter()
+                .cloned()
+                .chain([("DD_TRACE_EXPERIMENTAL_FEATURES_ENABLED", Some("true"))])
+                .collect::<Vec<_>>(),
+            || {
+                let config = config::Config::new().unwrap();
+                assert!(config.experimental_features_enabled);
+                assert_eq!(
+                    config.additional_metric_tags,
+                    vec!["region".to_string(), "tenant_id".to_string()]
+                );
+                assert_eq!(config.additional_metric_tags_cardinality_limit, Some(50));
+            },
+        );
+    }
 }
 
 /// Test helpers for creating Config instances in tests
@@ -782,6 +865,9 @@ pub mod test_helpers {
             proxy_url: None,
             env: "none".to_string(),
             peer_tags: peer_tag_keys().unwrap(),
+            experimental_features_enabled: false,
+            additional_metric_tags: vec![],
+            additional_metric_tags_cardinality_limit: None,
             agent_stats_computation_enabled: false,
         }
     }