feat(datadog): add stateless Foldspace retry fallback

.vale/styles/config/vocabularies/technical/accept.txt

@@ -18,6 +18,7 @@ newtype
 boolean(s?)
 ddsketch
 datadog
+foldspace
 otel
 serde
 stdin
@@ -95,6 +96,7 @@ inlining
 cloneable
 callsite
 enqueue(s|d|ing)?
+dequeue(s|d|ing)?
 hostname
 backpressure
 misconfiguration

Cargo.toml

@@ -114,6 +114,9 @@ bitmask-enum = { version = "2.2", default-features = false }
 facet = { version = "0.46.0", default-features = false, features = ["std"] }
 figment = { version = "0.10", default-features = false }
 foldhash = { version = "0.2", default-features = false, features = ["std"] }
+foldspace-core = { git = "https://github.com/DataDog/foldspace", rev = "c585fd1fc09758eb61e133b0e4e023a01c82cb26" }
+foldspace-patterns = { git = "https://github.com/DataDog/foldspace", rev = "c585fd1fc09758eb61e133b0e4e023a01c82cb26", features = ["core-adapter"] }
+foldspace-server = { git = "https://github.com/DataDog/foldspace", rev = "c585fd1fc09758eb61e133b0e4e023a01c82cb26" }
 headers = { version = "0.4", default-features = false }
 http = { version = "1", default-features = false }
 http-body = { version = "1", default-features = false }
@@ -164,6 +167,7 @@ similar-asserts = { version = "2.0", default-features = false }
 slab = { version = "0.4.12", default-features = false }
 syn = { version = "2", default-features = false, features = ["full", "parsing", "visit-mut"] }
 tokio-util = { version = "0.7.18", default-features = false }
+tokio-stream = { version = "0.1", default-features = false }
 tower = { version = "0.5", default-features = false }
 tracing-subscriber = { version = "0.3", default-features = false }
 typify = { version = "0.7", default-features = false }
@@ -212,6 +216,7 @@ crossbeam-queue = { version = "0.3", default-features = false, features = [
   "alloc",
 ] }
 float-cmp = { version = "0.10", default-features = false }
+flate2 = { version = "1", default-features = false, features = ["rust_backend"] }
 tower-http = { version = "0.7", default-features = false }
 bollard = { version = "0.21", default-features = false }
 home = { version = "0.5", default-features = false }

LICENSE-3rdparty.csv

@@ -127,6 +127,11 @@ flate2,https://github.com/rust-lang/flate2-rs,MIT OR Apache-2.0,"Alex Crichton <
 float-cmp,https://github.com/mikedilger/float-cmp,MIT,Mike Dilger <mike@mikedilger.com>
 fnv,https://github.com/servo/rust-fnv,Apache-2.0  OR  MIT,Alex Crichton <alex@alexcrichton.com>
 foldhash,https://github.com/orlp/foldhash,Zlib,Orson Peters <orsonpeters@gmail.com>
+foldspace-core,https://github.com/DataDog/foldspace,Apache-2.0,The foldspace-core Authors
+foldspace-eviction,https://github.com/DataDog/foldspace,Apache-2.0,The foldspace-eviction Authors
+foldspace-patterns,https://github.com/DataDog/foldspace,Apache-2.0,The foldspace-patterns Authors
+foldspace-patterns-tokenizer,https://github.com/DataDog/foldspace,Apache-2.0,The foldspace-patterns-tokenizer Authors
+foldspace-server,https://github.com/DataDog/foldspace,Apache-2.0,The foldspace-server Authors
 form_urlencoded,https://github.com/servo/rust-url,MIT OR Apache-2.0,The rust-url developers
 fs4,https://github.com/al8n/fs4-rs,MIT OR Apache-2.0,"Dan Burkert <dan@danburkert.com>, Al Liu <scygliu1@gmail.com>"
 futures,https://github.com/rust-lang/futures-rs,MIT OR Apache-2.0,The futures Authors
@@ -301,6 +306,8 @@ prost-types,https://github.com/tokio-rs/prost,Apache-2.0,"Dan Burkert <dan@danbu
 protobuf,https://github.com/stepancheg/rust-protobuf,MIT,Stepan Koltsov <stepan.koltsov@gmail.com>
 protobuf-parse,https://github.com/stepancheg/rust-protobuf/tree/master/protobuf-parse,MIT,Stepan Koltsov <stepan.koltsov@gmail.com>
 protobuf-support,https://github.com/stepancheg/rust-protobuf,MIT,Stepan Koltsov <stepan.koltsov@gmail.com>
+pulldown-cmark,https://github.com/raphlinus/pulldown-cmark,MIT,"Raph Levien <raph.levien@gmail.com>, Marcus Klaas de Vries <mail@marcusklaas.nl>"
+pulldown-cmark-to-cmark,https://github.com/Byron/pulldown-cmark-to-cmark,Apache-2.0,"Sebastian Thiel <byronimo@gmail.com>, Dylan Owen <dyltotheo@gmail.com>, Alessandro Ogier <alessandro.ogier@gmail.com>, Zixian Cai <2891235+caizixian@users.noreply.github.com>, Andrew Lyjak <andrew.lyjak@gmail.com>"
 quanta,https://github.com/metrics-rs/quanta,MIT,Toby Lawrence <toby@nuclearfurnace.com>
 quick_cache,https://github.com/arthurprs/quick-cache,MIT,Arthur Silva <arthurprs@gmail.com>
 quote,https://github.com/dtolnay/quote,MIT OR Apache-2.0,David Tolnay <dtolnay@gmail.com>
@@ -455,6 +462,7 @@ typify-impl,https://github.com/oxidecomputer/typify,Apache-2.0,The typify-impl A
 ucd-trie,https://github.com/BurntSushi/ucd-generate,MIT OR Apache-2.0,Andrew Gallant <jamslam@gmail.com>
 unarray,https://github.com/cameron1024/unarray,MIT OR Apache-2.0,The unarray Authors
 uncased,https://github.com/SergioBenitez/uncased,MIT OR Apache-2.0,Sergio Benitez <sb@sergio.bz>
+unicase,https://github.com/seanmonstar/unicase,MIT OR Apache-2.0,Sean McArthur <sean@seanmonstar.com>
 unicode-ident,https://github.com/dtolnay/unicode-ident,(MIT OR Apache-2.0) AND Unicode-3.0,David Tolnay <dtolnay@gmail.com>
 unicode-segmentation,https://github.com/unicode-rs/unicode-segmentation,MIT OR Apache-2.0,"kwantam <kwantam@gmail.com>, Manish Goregaokar <manishsmail@gmail.com>"
 unicode-width,https://github.com/unicode-rs/unicode-width,MIT OR Apache-2.0,"kwantam <kwantam@gmail.com>, Manish Goregaokar <manishsmail@gmail.com>"

bin/agent-data-plane/src/cli/run.rs

@@ -410,7 +410,8 @@ async fn create_topology(
             &metrics_encoding,
             &endpoints,
         )
-        .error_context("Failed to configure Datadog forwarder.")?;
+        .error_context("Failed to configure Datadog forwarder.")?
+        .with_stateful_logs(config_system.config().domains.logs.stateful.clone());
         blueprint.add_forwarder("dd_out", dd_forwarder_config)?;
     }
 

docs/agent-data-plane/configuration/configuration.md

@@ -458,6 +458,7 @@ The following settings are specific to ADP and have no equivalent in the core ag
 | `dogstatsd_string_interner_size_bytes`                          | Explicit byte budget for context interner  |                |
 | `dogstatsd_tcp_port`                                            | TCP listen port for DSD                    |                |
 | `flush_timeout_secs`                                            | Encoder flush timeout (secs)               |                |
+| `logs_config.use_grpc`                                          | Use stateful Foldspace transport for logs  | false          |
 | `memory_limit`                                                  | Process memory limit                       |                |
 | `memory_slop_factor`                                            | Memory accounting slop fraction            | 0.25           |
 | `otlp_allow_context_heap_allocs`                                | Allow heap allocations for OTLP contexts   |                |
@@ -470,6 +471,10 @@ The following settings are specific to ADP and have no equivalent in the core ag
 | `otlp_string_interner_size`                                     | OTLP context interner capacity             |                |
 | `serializer_max_metrics_per_payload`                            | Max metrics per payload                    |                |
 
+### `logs_config.use_grpc`
+
+Enables the initial stateful logs transport. Failed or queued stateful payloads are reconstructed and stored as complete stateless HTTP transactions before entering the normal retry or persisted queues. This does not provide full crash durability: a process crash before conversion can lose unacknowledged stateful payloads, and the persisted queue retains its existing dequeue crash window.
+
 ### `data_plane.otlp.receiver_grpc_endpoint_temporary`
 
 Temporary development key for setting ADP's OTLP listen endpoints independently from the Agent's.

lib/agent-data-plane-config-system/src/saluki_only.rs

@@ -160,6 +160,8 @@ pub struct SalukiOnly {
     pub apm_config: ApmConfig,
     /// OTLP receiver and trace knobs (`otlp_config.*`).
     pub otlp_config: OtlpConfig,
+    /// Logs transport knobs (`logs_config.*`).
+    pub logs_config: LogsConfig,
     /// OTTL span-drop filter (`ottl_filter_config`).
     pub ottl_filter_config: Option<OttlFilterConfig>,
     /// OTTL span-transform processor (`ottl_transform_config`).
@@ -213,6 +215,14 @@ pub struct DataPlaneChecks {
     pub enabled: Option<bool>,
 }
 
+/// `logs_config.*` transport settings absent from the vendored Datadog schema.
+#[derive(Clone, Debug, Default, Deserialize)]
+#[serde(default)]
+pub struct LogsConfig {
+    /// Whether stateful Foldspace transport is enabled (`logs_config.use_grpc`).
+    pub use_grpc: Option<bool>,
+}
+
 /// `apm_config.*` Saluki-only knobs. (The Datadog Agent publishes many other `apm_config.*` keys;
 /// those are witnessed and ignored here.)
 #[derive(Clone, Debug, Default, Deserialize)]
@@ -418,6 +428,11 @@ impl SalukiOnly {
             config.shared.metrics_encoding.max_metrics_per_payload = v;
         }
 
+        // domains.logs
+        if let Some(v) = self.logs_config.use_grpc {
+            config.domains.logs.stateful.enabled = v;
+        }
+
         // domains.dogstatsd
         let dsd = &mut config.domains.dogstatsd;
         if let Some(v) = self.dogstatsd_tcp_port {
@@ -641,6 +656,7 @@ mod tests {
                     "ignore_missing_datadog_fields": true
                 }
             },
+            "logs_config": { "use_grpc": true },
             // top-level objects
             "ottl_filter_config": { "error_mode": "ignore", "traces": { "span": ["attributes[\"a\"] == \"b\""] } },
             "ottl_transform_config": { "error_mode": "silent", "trace_statements": ["set(name, \"x\")"] },
@@ -663,6 +679,9 @@ mod tests {
         assert_eq!(config.shared.metrics_encoding.flush_timeout, Duration::from_secs(7));
         assert_eq!(config.shared.metrics_encoding.max_metrics_per_payload, 999);
 
+        // domains.logs
+        assert!(config.domains.logs.stateful.enabled);
+
         // domains.dogstatsd
         let dsd = &config.domains.dogstatsd;
         assert_eq!(dsd.listeners.tcp_port, 8126);
@@ -786,5 +805,6 @@ mod tests {
         assert_eq!(otlp.receiver.grpc.endpoint, "localhost:6317");
         assert_eq!(otlp.receiver.http.endpoint, "localhost:6318");
         assert_eq!(otlp.traces.string_interner_size, DEFAULT_STRING_INTERNER_SIZE_BYTES);
+        assert!(!config.domains.logs.stateful.enabled);
     }
 }

lib/agent-data-plane-config/src/domains/logs.rs

@@ -0,0 +1,19 @@
+//! Logs domain configuration.
+
+use serde::Serialize;
+
+/// Resolved logs configuration.
+#[derive(Clone, Debug, Default, PartialEq, Serialize)]
+pub struct Domain {
+    /// Stateful Foldspace transport configuration.
+    pub stateful: StatefulEncoding,
+}
+
+/// Stateful Foldspace transport configuration.
+#[derive(Clone, Debug, Default, PartialEq, Serialize)]
+pub struct StatefulEncoding {
+    /// Whether logs use stateful gRPC encoding.
+    ///
+    /// Defaults to `false`. Enable this only when the configured logs intake supports Foldspace.
+    pub enabled: bool,
+}

lib/agent-data-plane-config/src/domains/mod.rs

@@ -6,6 +6,7 @@ use serde::Serialize;
 
 pub mod checks;
 pub mod dogstatsd;
+pub mod logs;
 pub mod multi_region_failover;
 pub mod otlp;
 pub mod traces;
@@ -14,6 +15,7 @@ pub mod traces;
 #[derive(Clone, Debug, Default, PartialEq, Serialize)]
 pub struct DomainConfiguration {
     pub dogstatsd: dogstatsd::Domain,
+    pub logs: logs::Domain,
     pub otlp: otlp::Domain,
     pub traces: traces::Domain,
     pub checks: checks::Domain,

lib/datadog-agent/config-overlay-model/src/saluki_keys.rs

@@ -22,6 +22,27 @@ pub struct SalukiKey {
 }
 
 pub static SALUKI_KEYS: &[SalukiKey] = &[
+    // ── logs.rs ─────────────────────────────────────────────────────────────
+    SalukiKey {
+        yaml_path: "logs_config.use_grpc",
+        description: "Use stateful Foldspace transport for logs",
+        default: "false",
+        documentation: Some(
+            "Enables the initial stateful logs transport. Failed or queued stateful payloads are reconstructed and \
+             stored as complete stateless HTTP transactions before entering the normal retry or persisted queues. \
+             This does not provide full crash durability: a process crash before conversion can lose unacknowledged \
+             stateful payloads, and the persisted queue retains its existing dequeue crash window.",
+        ),
+        value_type: "ValueType::Bool",
+        schema_default: Some("false"),
+        env_vars: &[],
+        env_var_override: None,
+        additional_yaml_paths: &[],
+        used_by: &["TYPED_CONFIG_SYSTEM"],
+        test_json: None,
+        pipeline_affinity: "PipelineAffinity::Pipelines(&[Pipeline::Checks, Pipeline::Otlp])",
+        filename: "logs.rs",
+    },
     // ── data_plane.rs ────────────────────────────────────────────────────────
     SalukiKey {
         yaml_path: "data_plane.otlp.receiver_grpc_endpoint_temporary",

lib/datadog-agent/config-testing/src/config_registry/annotations_index.rs

@@ -18,6 +18,7 @@ mod dogstatsd_prefix_filter;
 mod encoders;
 mod forwarder;
 mod get_typed;
+mod logs;
 mod mrf;
 mod otlp;
 mod proxy;
@@ -40,6 +41,7 @@ pub static SUPPORTED_ANNOTATIONS: LazyLock<Vec<&'static SalukiAnnotation>> = Laz
     v.extend_from_slice(encoders::ALL);
     v.extend_from_slice(forwarder::ALL);
     v.extend_from_slice(get_typed::ALL);
+    v.extend_from_slice(logs::ALL);
     v.extend_from_slice(mrf::ALL);
     v.extend_from_slice(otlp::ALL);
     v.extend_from_slice(proxy::ALL);