67 lines
2.3 KiB
JavaScript
67 lines
2.3 KiB
JavaScript
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import assert from 'assert'
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import { CID } from 'multiformats/cid'
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import * as json from 'multiformats/codecs/json'
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import { sha256 } from 'multiformats/hashes/sha2'
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import { base64 } from 'multiformats/bases/base64'
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async function run () {
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// ** PART 1: CREATING A NEW CID **
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// Arbitrary input value
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const value = { hello: 'world' }
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// Encoded Uint8array representation of `value` using the plain JSON IPLD codec
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const bytes = json.encode(value)
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// Hash Uint8array representation
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const hash = await sha256.digest(bytes)
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// Create CID (default base32)
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const cid = CID.create(1, json.code, hash)
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// cid.code --> 512 (0x0200) JSON IPLD codec)
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// cid.version --> 1
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// cid.multihash --> digest, including code (18 for sha2-256), digest size (32 bytes)
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// cid.bytes --> byte representation`
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console.log('Example CID: ' + cid.toString())
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// 'bagaaierasords4njcts6vs7qvdjfcvgnume4hqohf65zsfguprqphs3icwea'
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// ** PART 2: MULTIBASE ENCODERS / DECODERS / CODECS **
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// Encode CID from part 1 to base64, decode back to base32
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const cidBase64 = cid.toString(base64.encoder)
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console.log('base64 encoded CID: ' + cidBase64)
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// 'mAYAEEiCTojlxqRTl6svwqNJRVM2jCcPBxy+7mRTUfGDzy2gViA'
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const cidBase32 = CID.parse(cidBase64, base64.decoder)
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// 'bagaaierasords4njcts6vs7qvdjfcvgnume4hqohf65zsfguprqphs3icwea'
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// test decoded CID against original
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assert.strictEqual(cidBase32.toString(), cid.toString(), 'Warning: decoded base32 CID does not match original')
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console.log('Decoded CID equal to original base32: ' + cidBase32.equals(cid)) // alternatively, use more robust built-in function to test equivalence
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// Multibase codec exposes both encoder and decoder properties
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cid.toString(base64)
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CID.parse(cid.toString(base64), base64)
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// ** PART 3: CID BASE CONFIGURATIONS **
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// CID v1 default encoding is base32
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const v1 = CID.parse('bagaaierasords4njcts6vs7qvdjfcvgnume4hqohf65zsfguprqphs3icwea')
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v1.toString()
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// 'bagaaierasords4njcts6vs7qvdjfcvgnume4hqohf65zsfguprqphs3icwea'
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// CID v0 default encoding is base58btc
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const v0 = CID.parse('QmdfTbBqBPQ7VNxZEYEj14VmRuZBkqFbiwReogJgS1zR1n')
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v0.toString()
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// 'QmdfTbBqBPQ7VNxZEYEj14VmRuZBkqFbiwReogJgS1zR1n'
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v0.toV1().toString()
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// 'bafybeihdwdcefgh4dqkjv67uzcmw7ojee6xedzdetojuzjevtenxquvyku'
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}
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run().catch((err) => {
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console.error(err)
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process.exit(1)
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})
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