Generate File Hash Locally on Browser

Help js-ipfs
1

Hi everyone! I’m glad to be part of this community!

Hopefully someone can help me with my following issue!

What I’m trying to do is to generate the IPFS hash of a file while the user is using a PWA offline (just a web app). If I’m connected, I can just ipfs.add to add a file and get the file hash, no sweat. Now, if I’m offline I need to hash it locally and want the same output as if I added to an IPFS node.

This is the code that I got so far:

import { importer } from "ipfs-unixfs-importer";
import IPLD from "ipld";
import ipldInMemory from "ipld-in-memory";

async function* asAsyncIterable(arr: Uint8Array) {
    yield* [arr];
}

const ipfsQhashFile = async (file: File) => {
    const fileName = file.name;
    const bytes = new Uint8Array(await file.arrayBuffer());

    const ipld = await ipldInMemory(IPLD, {});
    const source = {
        path: fileName,
        content: asAsyncIterable(bytes), //AsyncIterable<Uint8Array>
    };

    const cids = [];
    for await (const entry of importer(source, ipld)) {
        console.info(">>> entry", entry);
        cids.push(entry);
    }
};

And when I run the function ipfsQhashFile with a file that the user selected on a fileinput field I receive the following error:

Error: `format` parameter must be number (multicodec)
    at IPLDResolver.put (index.js:197)
    at persist (persist.js:33)
    at :3000/async http:/localhost:3000/static/js/vendors~main.chunk.js:32539
    at async parallelBatch (index.js:36)
    at async buildFileBatch (index.js:47)
    at async batch (index.js:20)
    at async reduceToParents (balanced.js:22)
    at async parallelBatch (index.js:36)
    at async treeBuilder (tree-builder.js:95)
    at async importer (index.js:59)
    at async ipfsQhashFile (ipfs.ts:21)

Does anyone know what I’m missing?

Thank you!

2

Does this help? GitHub - alanshaw/ipfs-only-hash: #️⃣ Just enough code to calculate the IPFS hash for some data

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