chadtmiller.com
+69
-1
src/pds.js
+69
-1
src/pds.js
···
376
376
}
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}
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+
// === CAR FILE BUILDER ===
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+
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function varint(n) {
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const bytes = []
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while (n >= 0x80) {
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bytes.push((n & 0x7f) | 0x80)
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n >>>= 7
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}
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bytes.push(n)
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return new Uint8Array(bytes)
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}
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+
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function cidToBytes(cidStr) {
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// Decode base32lower CID string to bytes
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if (!cidStr.startsWith('b')) throw new Error('expected base32lower CID')
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return base32Decode(cidStr.slice(1))
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}
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+
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function base32Decode(str) {
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const alphabet = 'abcdefghijklmnopqrstuvwxyz234567'
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let bits = 0
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let value = 0
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const output = []
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+
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for (const char of str) {
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const idx = alphabet.indexOf(char)
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if (idx === -1) continue
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value = (value << 5) | idx
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+
bits += 5
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if (bits >= 8) {
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bits -= 8
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output.push((value >> bits) & 0xff)
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+
}
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}
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return new Uint8Array(output)
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}
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+
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function buildCarFile(rootCid, blocks) {
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const parts = []
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+
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// Header: { version: 1, roots: [rootCid] }
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const rootCidBytes = cidToBytes(rootCid)
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const header = cborEncode({ version: 1, roots: [rootCidBytes] })
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parts.push(varint(header.length))
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parts.push(header)
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+
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// Blocks: varint(len) + cid + data
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for (const block of blocks) {
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const cidBytes = cidToBytes(block.cid)
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+
const blockLen = cidBytes.length + block.data.length
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+
parts.push(varint(blockLen))
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+
parts.push(cidBytes)
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+
parts.push(block.data)
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+
}
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+
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+
// Concatenate all parts
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const totalLen = parts.reduce((sum, p) => sum + p.length, 0)
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const car = new Uint8Array(totalLen)
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+
let offset = 0
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+
for (const part of parts) {
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car.set(part, offset)
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+
offset += part.length
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+
}
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+
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+
return car
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+
}
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+
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export class PersonalDataServer {
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constructor(state, env) {
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449
this.state = state
···
635
703
export {
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704
cborEncode, cborDecode, createCid, cidToString, base32Encode, createTid,
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705
generateKeyPair, importPrivateKey, sign, bytesToHex, hexToBytes,
638
-
getKeyDepth
706
+
getKeyDepth, varint, base32Decode, buildCarFile
639
707
}
+36
-1
test/pds.test.js
+36
-1
test/pds.test.js
···
3
3
import {
4
4
cborEncode, cborDecode, createCid, cidToString, base32Encode, createTid,
5
5
generateKeyPair, importPrivateKey, sign, bytesToHex, hexToBytes,
6
-
getKeyDepth
6
+
getKeyDepth, varint, base32Decode, buildCarFile
7
7
} from '../src/pds.js'
8
8
9
9
describe('CBOR Encoding', () => {
···
265
265
assert.deepStrictEqual(decoded, original)
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266
})
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267
})
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+
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+
describe('CAR File Builder', () => {
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+
test('varint encodes small numbers', () => {
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+
assert.deepStrictEqual(varint(0), new Uint8Array([0]))
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+
assert.deepStrictEqual(varint(1), new Uint8Array([1]))
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+
assert.deepStrictEqual(varint(127), new Uint8Array([127]))
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+
})
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+
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+
test('varint encodes multi-byte numbers', () => {
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+
// 128 = 0x80 -> [0x80 | 0x00, 0x01] = [0x80, 0x01]
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+
assert.deepStrictEqual(varint(128), new Uint8Array([0x80, 0x01]))
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+
// 300 = 0x12c -> [0xac, 0x02]
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+
assert.deepStrictEqual(varint(300), new Uint8Array([0xac, 0x02]))
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+
})
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+
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+
test('base32 encode/decode roundtrip', () => {
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+
const original = new Uint8Array([0x01, 0x71, 0x12, 0x20, 0xab, 0xcd])
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+
const encoded = base32Encode(original)
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+
const decoded = base32Decode(encoded)
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+
assert.deepStrictEqual(decoded, original)
288
+
})
289
+
290
+
test('buildCarFile produces valid structure', async () => {
291
+
const data = cborEncode({ test: 'data' })
292
+
const cid = await createCid(data)
293
+
const cidStr = cidToString(cid)
294
+
295
+
const car = buildCarFile(cidStr, [{ cid: cidStr, data }])
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+
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+
assert.ok(car instanceof Uint8Array)
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+
assert.ok(car.length > 0)
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+
// First byte should be varint of header length
300
+
assert.ok(car[0] > 0)
301
+
})
302
+
})