Add batchupdateobjects RPC for per-vnode atomic batch updates

New Fast RPC endpoint that accepts multiple UpdateObjectPayload
items, groups them by vnode, and executes each vnode group
within a single PostgreSQL transaction. Objects in the same
vnode succeed or fail atomically; cross-vnode failures are
isolated.

Changes:
- object/batch_update.rs: payload types, decode, action handler,
  vnode grouping, per-vnode transaction orchestration
- lib.rs: register batchupdateobjects in handle_msg dispatch
- object.rs: add batch_update module
- sql.rs: add ObjectBatchUpdate method variant

=== AI-METADATA ===
AI-Tool: Claude Code
AI-Model: claude-opus-4-6
AI-Role: boilerplate code generation
Human-Role: code review, implementation guidance, design decisions

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

Author: cneira

Makefile

@@ -1,6 +1,7 @@
 #
 # Copyright 2020 Joyent, Inc.
 # Copyright 2023 MNX Cloud, Inc.
+# Copyright 2026 Edgecast Cloud LLC.
 #
 
 NAME = manta-buckets-mdapi
@@ -104,12 +105,16 @@ build-buckets-mdapi: | $(CARGO_EXEC)
 	$(CARGO) build --release
 
 .PHONY: test
-test: test-unit
+test: test-unit test-integration
 
 .PHONY: test-unit
 test-unit: | $(CARGO_EXEC)
 	$(CARGO) test --lib
 
+.PHONY: test-integration
+test-integration: | $(CARGO_EXEC)
+	$(CARGO) test --test rpc_handlers -- --nocapture
+
 include ./deps/eng/tools/mk/Makefile.deps
 include ./deps/eng/tools/mk/Makefile.agent_prebuilt.targ
 include ./deps/eng/tools/mk/Makefile.smf.targ

README.md

@@ -128,3 +128,10 @@ The functional tests require that postgresql is installed as well as
 and configure a temporary postgres database and once the test has completed the
 temporary database is removed within a few seconds. The tests use the same code
 used by the `schema-manager` to prepare the database for use by the test suite.
+
+To build `ephemeralpg` from source on SmartOS, the socket library must be linked
+explicitly:
+
+```
+LDFLAGS=-lsocket make
+```

buckets-mdapi/src/lib.rs

@@ -1,4 +1,5 @@
 // Copyright 2020 Joyent, Inc.
+// Copyright 2026 Edgecast Cloud LLC.
 
 #![allow(clippy::module_name_repetitions)]
 
@@ -123,6 +124,17 @@ pub mod util {
                         metrics,
                         log,
                     ),
+                    "batchupdateobjects" => handle_request(
+                        msg.id,
+                        method,
+                        object::batch_update::decode_msg(
+                            &msg.data.d,
+                        ),
+                        &mut conn,
+                        &object::batch_update::action,
+                        metrics,
+                        log,
+                    ),
                     "deleteobject" => handle_request(
                         msg.id,
                         method,

buckets-mdapi/src/object.rs

@@ -1,5 +1,6 @@
 // Copyright 2020 Joyent, Inc.
 // Copyright 2023 MNX Cloud, Inc.
+// Copyright 2026 Edgecast Cloud LLC.
 
 use std::error::Error;
 use std::vec::Vec;
@@ -16,6 +17,7 @@ use crate::conditional;
 use crate::error::BucketsMdapiError;
 use crate::types::{HasRequestId, Hstore, RowSlice, Timestamptz};
 
+pub mod batch_update;
 pub mod create;
 pub mod delete;
 pub mod get;