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avsc Barification

What was changed from the upstream mtth/avsc to run on Bare, and why.

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Approach

Bare ships with no standard library. Node.js built-ins like fs, crypto, stream, and path do not exist. Their Bare equivalents — bare-fs, bare-crypto, bare-stream, bare-path — provide the same functionality through separately installed modules.

The fork replaces all Node.js requires with their Bare equivalents directly. No conditional imports, no runtime detection, no compatibility layers. The code targets one runtime.

Module Replacements

platform.js

// upstream
let crypto = require('crypto')

// fork
let crypto = require('bare-crypto')

Provides getHash(str, algorithm) — used for schema fingerprints (MD5) and protocol handshake hashes.

files.js

// upstream
let fs = require('fs')
let path = require('path')

// fork
let fs = require('bare-fs')
let path = require('bare-path')

Provides import hooks for IDL file resolution — reading .avdl, .avsc, and .avpr files from the filesystem.

index.js

// upstream
let fs = require('fs')

// fork
let fs = require('bare-fs')

The main entry point uses filesystem access for container file convenience functions (createFileDecoder, createFileEncoder, extractFileHeader).

containers.js

// upstream
let stream = require('stream')

// fork
let stream = require('bare-stream')

Block and raw encoder/decoder streams for Avro container file I/O.

TextEncoder/TextDecoder Polyfill

File: lib/encoding.js

Bare’s text-decoder module provides a streaming API (push/write/end). avsc expects the WHATWG standard API — TextDecoder.decode(buf) and TextEncoder.encodeInto(str, buf).

The polyfill provides WHATWG-compliant implementations with full UTF-8 support (1–4 byte sequences, surrogate pair handling). It installs on globalThis only if the standard API is absent.

Auto-loaded via require('./encoding') in utils.js.

Buffer Handling

utils.js contains conditional logic that checks for Buffer availability:

if (typeof Buffer === 'function') {
  // Use Buffer methods
} else {
  // Fall back to Uint8Array operations
}

On Bare, Buffer is available when bare-buffer is required but is not a global. The conditional handling ensures avsc works whether Buffer is present or not.

Package.json

Upstream avsc v6 had a conditional imports field:

{
  "imports": {
    "fs": { "bare": "bare-fs", "default": "fs" },
    "crypto": { "bare": "bare-crypto", "default": "crypto" }
  }
}

The fork strips this to:

{
  "name": "avsc",
  "main": "lib/index.js"
}

No conditional resolution. Direct requires to bare-* modules throughout. One runtime, one code path.

Platform Dependencies

Required at runtime, installed by bin/setup:

Module	Version	Purpose
bare-crypto	4.7.0	Schema fingerprints, protocol hashes
bare-fs	4.7.0	Container file I/O, IDL imports
bare-path	3.0.0	IDL import path resolution
bare-stream	2.13.0	Container encoding/decoding streams

These are platform dependencies — not committed to the repository, populated by the setup script into lib/. The node_modules → lib/ symlink makes them resolvable by name.

See Code Implementation for the full dependency management model.