use "JSON Canonicalization Scheme" (JSC) as deterministic JSON stringify (#4)

lib/feed-v1/get-msg-id.js

@@ -1,6 +1,6 @@
 const blake3 = require('blake3')
 const base58 = require('bs58')
-const stringify = require('fast-json-stable-stringify')
+const stringify = require('canonicalize')
 
 /**
  * @typedef {import('./index').Msg} Msg

lib/feed-v1/index.js

@@ -2,7 +2,7 @@
 //
 // SPDX-License-Identifier: LGPL-3.0-only
 
-const stringify = require('fast-json-stable-stringify')
+const stringify = require('canonicalize')
 const ed25519 = require('ssb-keys/sodium')
 const base58 = require('bs58')
 const union = require('set.prototype.union')

lib/feed-v1/represent-content.js

@@ -1,6 +1,6 @@
 const blake3 = require('blake3')
 const base58 = require('bs58')
-const stringify = require('fast-json-stable-stringify')
+const stringify = require('canonicalize')
 
 /**
  * @param {any} content

lib/feed-v1/validation.js

@@ -1,6 +1,6 @@
 const base58 = require('bs58')
 const ed25519 = require('ssb-keys/sodium')
-const stringify = require('fast-json-stable-stringify')
+const stringify = require('canonicalize')
 const Tangle = require('./tangle')
 const representContent = require('./represent-content')
 

package.json

@@ -30,7 +30,7 @@
     "async-append-only-log": "^4.3.10",
     "blake3": "^2.1.7",
     "bs58": "^5.0.0",
-    "fast-json-stable-stringify": "^2.1.0",
+    "canonicalize": "^2.0.0",
     "obz": "^1.1.0",
     "promisify-4loc": "^1.0.0",
     "push-stream": "^11.2.0",

protospec.md

@@ -65,9 +65,4 @@ Given the root msg ID, any peer can thus refer to the feed tangle, because the r
 
 ## JSON serialization
 
-Whenever we need to serialize any JSON in the context of creating a Feed V1 message, we use the following rules:
-
-- Object fields are ordered alphabetically by field key
-- No whitespace nor newliners are added
-- No trailing commas are added
-- UTF-8 encoding
+Whenever we need to serialize any JSON in the context of creating a Feed V1 message, we follow the "JSON Canonicalization Scheme" (JSC) defined by [RFC 8785](https://tools.ietf.org/html/rfc8785).