Home > Engineering > Infrastructure > bare-for-pear > avsc-rpc

avsc-rpc — Avro RPC Protocol

Reference for avsc-rpc — the Avro RPC protocol layer that provides mycelium’s process boundary enforcement.

---

What avsc-rpc Is

avsc-rpc is the Avro RPC/IPC implementation extracted from avsc v5 and maintained as a standalone library for the Bare runtime. Service definition, client/server creation, transport channels, middleware, and protocol negotiation.

The RPC layer was removed from avsc in v6 (PR #428). This module preserves and maintains it independently.

Source: github.com/bare-for-pear/avsc-rpc Extracted from: commit dd82783 of mtth/avsc

Why avsc-rpc Is Constitutive

RPC is not a communication mechanism in mycelium. It is the process boundary enforcement mechanism.

Two processes communicating through RPC can only see each other through the schema contract. No shared objects, no classpath leakage, no hidden state. Even in local in-memory execution, the RPC boundary guarantees that only schema-conformant messages pass. This is what makes the architecture’s claim — no transitive dependencies between processes — a physical fact rather than a convention.

Transport pluggability is a consequence, not the motivation. The same schema contract holds whether the transport is in-memory, TCP, or HTTP. The transport adapts to context. The boundary is invariant.

This makes avsc-rpc constitutive alongside avsc itself. Together they provide the complete Avro primitive: types and serialization from avsc, protocol and boundary from avsc-rpc.

See AVRO Design Scope — section 11, RPC as Constitutive Dependency — for the full architectural role.

What the Fork Changes

The extraction adapted the code for standalone use on Bare:

Concern	Upstream (avsc v5)	Fork
Streams	stream.Transform	streamx.Transform
Buffer	buffer	bare-buffer
Events	events	bare-events
Streams	stream	bare-stream

Additional adaptations:

• streamx transport — all frame encoder/decoder classes use streamx.Transform. Two-parameter _transform(buf, cb) — no encoding argument.
• v5/v6 compatibility bridge (compat.js) — avsc-rpc was written against avsc v5. The fork pairs it with avsc v6. The bridge handles hash result types (Uint8Array to Buffer), restored utility functions, and process.nextTick polyfill via queueMicrotask.
• Peer dependency on avsc — types and utils are imported directly from the avsc sibling. Both libraries live together under lib/.

Reference Pages

• Service Definition — protocols, messages, Service.forProtocol, type resolution
• Client and Server — creating clients and servers, handler registration, options
• Transports — in-memory, TCP, HTTP, channel lifecycle, stateful vs stateless
• Middleware — request/response chain, use patterns
• Wire Protocol — handshake, framing, Netty compatibility, protocol negotiation
• Barification — streamx adaptation, v5/v6 bridge, platform dependencies

Library Reference

The library’s own reference site: bare-for-pear.github.io/avsc-rpc — complete API documentation including full method signatures, all options, and wire format details.