feat(libdd-healthplatform): add no_std crate for agent-payload healthplatform.proto

Cargo.toml

@@ -51,6 +51,7 @@ members = [
   "libdd-ddsketch-ffi",
   "libdd-tinybytes",
   "libdd-dogstatsd-client",
+  "libdd-healthplatform",
   "libdd-http-client",
   "libdd-log",
   "libdd-log-ffi",

libdd-healthplatform/Cargo.toml

@@ -0,0 +1,47 @@
+# Copyright 2026-Present Datadog, Inc. https://www.datadoghq.com/
+# SPDX-License-Identifier: Apache-2.0
+
+[package]
+name = "libdd-healthplatform"
+version = "0.1.0"
+description = "no_std-first Rust types for Datadog's agent-payload healthplatform.proto"
+homepage = "https://github.com/DataDog/libdatadog/tree/main/libdd-healthplatform"
+repository = "https://github.com/DataDog/libdatadog/tree/main/libdd-healthplatform"
+rust-version.workspace = true
+edition.workspace = true
+license.workspace = true
+authors.workspace = true
+
+[lib]
+bench = false
+
+[features]
+default = []
+# Regenerate src/healthplatform.rs from src/pb/*.proto. Off by default; CI builds use checked-in output.
+generate-protobuf = ["dep:prost-build", "dep:protoc-bin-vendored"]
+# Build the evp_proxy example. Pulls in std + HTTP stack.
+example-client = ["dep:reqwest", "dep:tokio", "dep:anyhow", "dep:serde_json"]
+
+[dependencies]
+# default-features = false drops the std feature; prost-generated code only needs alloc + derive.
+prost = { version = "0.14.3", default-features = false, features = ["derive"] }
+prost-types = { version = "0.14.3", default-features = false }
+
+# Example-only deps -- gated. The example POSTs to a localhost trace-agent over plain HTTP, no TLS needed.
+reqwest = { version = "0.13.2", default-features = false, optional = true }
+tokio = { version = "1.43", features = ["macros", "rt-multi-thread"], optional = true }
+anyhow = { version = "1.0", optional = true }
+serde_json = { version = "1.0", optional = true }
+
+[build-dependencies]
+prost-build = { version = "0.14.3", optional = true }
+protoc-bin-vendored = { version = "3.2", optional = true }
+
+[dev-dependencies]
+# std + prost-with-std for round-trip tests.
+prost = "0.14.3"
+prost-types = "0.14.3"
+
+[[example]]
+name = "evp_proxy_send"
+required-features = ["example-client"]

libdd-healthplatform/README.md

@@ -0,0 +1,26 @@
+# libdd-healthplatform
+
+`no_std + alloc` Rust types for Datadog's [`agent-payload` healthplatform protobuf schema][upstream-proto].
+Encode and decode are provided by the `prost::Message` trait that every generated type already implements
+— bring `prost::Message` into scope on the consumer side and call `encode_to_vec()` / `decode(bytes)`.
+
+## Regenerating bindings
+
+`src/healthplatform.rs` is checked in. Re-generate it whenever `src/pb/healthplatform.proto` changes:
+
+```sh
+cargo build -p libdd-healthplatform --features generate-protobuf
+```
+
+The vendored `.proto` records the upstream commit SHA in its header — bump it when re-vendoring.
+
+## Example client
+
+A minimal end-to-end demo that POSTs a JSON `HealthReport` through the trace-agent's `evp_proxy` endpoint
+lives at `examples/evp_proxy_send.rs`. Build it with:
+
+```sh
+cargo build -p libdd-healthplatform --example evp_proxy_send --features example-client
+```
+
+[upstream-proto]: https://github.com/DataDog/agent-payload/blob/master/proto/healthplatform/healthplatform.proto

libdd-healthplatform/build.rs

@@ -0,0 +1,73 @@
+// Copyright 2026-Present Datadog, Inc. https://www.datadoghq.com/
+// SPDX-License-Identifier: Apache-2.0
+
+use std::io::Result;
+
+#[cfg(feature = "generate-protobuf")]
+use {
+    std::env,
+    std::fs::File,
+    std::io::{Read, Write},
+    std::path::Path,
+};
+
+// to re-generate the protobuf structs, run:
+//   cargo build -p libdd-healthplatform --features generate-protobuf
+fn main() -> Result<()> {
+    #[cfg(feature = "generate-protobuf")]
+    {
+        std::env::set_var("PROTOC", protoc_bin_vendored::protoc_bin_path().unwrap());
+        generate_protobuf();
+    }
+    #[cfg(not(feature = "generate-protobuf"))]
+    {
+        println!("cargo:rerun-if-changed=build.rs");
+    }
+
+    Ok(())
+}
+
+#[cfg(feature = "generate-protobuf")]
+fn generate_protobuf() {
+    let cur_working_dir = env::var("CARGO_MANIFEST_DIR").unwrap();
+    let current_working_dir_path = Path::new(&cur_working_dir);
+    let output_path = current_working_dir_path.join("src");
+
+    let mut config = prost_build::Config::new();
+    config.out_dir(output_path.clone());
+    // Use BTreeMap for all map fields so the generated code stays no_std-clean.
+    // (HashMap requires the std feature on prost's encoding side.)
+    config.btree_map(["."]);
+
+    // prost-build maps `.google.protobuf` types to `::prost_types` automatically; we
+    // rely on prost-types' bundled descriptor for google/protobuf/struct.proto so we
+    // don't have to vendor it ourselves.
+    config
+        .compile_protos(&["src/pb/healthplatform.proto"], &["src/pb"])
+        .unwrap();
+
+    // prost-build emits a file named after the proto package: datadog.healthplatform.rs.
+    // Rename to healthplatform.rs so the include! path in lib.rs stays short.
+    let generated = output_path.join("datadog.healthplatform.rs");
+    let target = output_path.join("healthplatform.rs");
+    std::fs::rename(&generated, &target).unwrap();
+
+    let license = b"// Copyright 2026-Present Datadog, Inc. https://www.datadoghq.com/
+// SPDX-License-Identifier: Apache-2.0
+//
+// @generated by prost-build from src/pb/healthplatform.proto.
+// Do not edit by hand; run `cargo build -p libdd-healthplatform --features generate-protobuf`.
+
+";
+    prepend_to_file(license, &target);
+}
+
+#[cfg(feature = "generate-protobuf")]
+fn prepend_to_file(data: &[u8], file_path: &Path) {
+    let mut f = File::open(file_path).unwrap();
+    let mut content = data.to_owned();
+    f.read_to_end(&mut content).unwrap();
+
+    let mut f = File::create(file_path).unwrap();
+    f.write_all(content.as_slice()).unwrap();
+}