bellbind/multi-nodes-cdn.html

## multi-nodes-cdn.html
<!doctype html>
<html>
  <head>
    <link rel="icon" href="data:image/x-icon," />
    <script type="module" src="./multi-nodes-cdn.js"></script>
  </head>
  <body>
    Open JavaScript console to check running logs
  </body>
</html>

## multi-nodes-cdn.js
// This example runs 2 helia nodes for publishing and receiving data with cid string

// from CDN
import "https://cdn.jsdelivr.net/npm/helia@^1.3.2/dist/index.min.js";
import "https://cdn.jsdelivr.net/npm/@helia/unixfs@^1.3.0/dist/index.min.js";
import "https://cdn.jsdelivr.net/npm/multiformats@^12.0.1/dist/index.min.js";
const helia = Helia, {unixfs} = HeliaUnixfs, {CID} = Multiformats;
//import * as helia from "helia";
//import {unixfs} from "@helia/unixfs";
//import {CID} from "multiformats/cid";

//NOTE: current browsers not yet implement ReadableStream[Symbol.asyncIterator]
const rsWithAi = rs => { // supply ReadableStream[Symbol.asyncIterator]
  if (!(Symbol.asyncIterator in rs)) rs[Symbol.asyncIterator] = async function *() {
    const reader = rs.getReader();
    try {
      while (true) {
        const {value, done} = await reader.read();
        if (done) return;
        yield value;
      }
    } finally {
      reader.releaseLock();
    }
  };
  return rs;
};

//[1. start]
const node1 = await helia.createHelia(); // default: use memory strores (non-persistent)
const node2 = await helia.createHelia();
const node1fs = unixfs(node1);
const node2fs = unixfs(node2);
console.log("[createHelia]");

//[2. wait network established]
//IMPORTANT: For call dial() each other, must await libp2p.getMultiaddrs().length > 0
// - It is a big diffrence from js-ipfs behavior of `await createIpfs()`
while (node1.libp2p.getMultiaddrs().length === 0) await new Promise(f => setTimeout(f, 500));
while (node2.libp2p.getMultiaddrs().length === 0) await new Promise(f => setTimeout(f, 500));
console.log("[libp2p.getMultiaddrs]1", node1.libp2p.getMultiaddrs().map(ma => `${ma}`));
console.log("[libp2p.getMultiaddrs]2", node2.libp2p.getMultiaddrs().map(ma => `${ma}`));

// connect nodes directly with dial()
for (const ma of node2.libp2p.getMultiaddrs()) {
  try {
    //IMPORTANT: some of transports may fail to dial() directly
    await node1.libp2p.dial(ma);
    console.log(`[libp2p.dial] success: ${ma}`);
    break;
  } catch (error) {
    console.log(`[libp2p.dial] failed: ${ma}`);
  } // dial to other ma
}

//[3. feed content]
// example data
const blob = new Blob([new TextEncoder().encode("Hello World!")], {type: "text/plain;charset=utf-8"});
console.log("[Blob]", blob);

// publish blob as CID with addByteStream()
const cid = await node1fs.addByteStream(rsWithAi(blob.stream()));
//const cid = await node1fs.addBytes(new Uint8Array(await blob.arrayBuffer()));
console.log("[unixfs.addByteStream]", cid);
const cidStr = cid.toString();
const cidAlt = CID.parse(cidStr);
//NOTE: pins only accept when block data existed in node; cannot reserve pinning cid in advance
const ret1 = await node1.pins.add(cidAlt); //NOTE: pins.add() not accept CID string
console.log("[pins.add]", ret1);

//[4. retrieve content]
// NOTE: helia's pins needs stored blocks in blockstore (e.g. cannnot pin before stat()/ls()/cat())
const stat = await node2fs.stat(cidStr);
console.log("[unixfs.stat]", stat);
const ret2 = await node2.pins.add(cidAlt); //NOTE: accept pins.add(cid) after stat(cid) successed
console.log("[pins.add]", ret2);

// get CID object from CID string with ls() from @helia/unixfs
for await (const entry of node2fs.ls(cidStr)) {
  console.log("[unixfs.ls]", entry.cid);
}

// retrieve data with cat(cid or cid-string)
const u8as = [];
for await (const u8a of node2fs.cat(cidStr)) {
  console.log("[unixfs.cat]", u8a);
  u8as.push(u8a.slice()); //NOTE: create non shared Uint8Array instance with u8a.slice()
  //IMPORTANT: u8a returned maybe shared in helia impl, so it would crush when u8a.buffer is detached by some action
  // - ReadableStream controller.enqueue(u8a)
  // - postMessage(msg, [u8a.buffer])
}
console.log("[Blob.text]", await (new Blob(u8as).text()));

//[5. stop]
// stop only helia nodes; unixfs is just a wrapper
console.log("[helia.stop]", await Promise.all([node1.stop(), node2.stop()]));
	<!doctype html>
	<html>
	<head>
	<link rel="icon" href="data:image/x-icon," />
	<script type="module" src="./multi-nodes-cdn.js"></script>
	</head>
	<body>
	Open JavaScript console to check running logs
	</body>
	</html>
	// This example runs 2 helia nodes for publishing and receiving data with cid string

	// from CDN
	import "https://cdn.jsdelivr.net/npm/helia@^1.3.2/dist/index.min.js";
	import "https://cdn.jsdelivr.net/npm/@helia/unixfs@^1.3.0/dist/index.min.js";
	import "https://cdn.jsdelivr.net/npm/multiformats@^12.0.1/dist/index.min.js";
	const helia = Helia, {unixfs} = HeliaUnixfs, {CID} = Multiformats;
	//import * as helia from "helia";
	//import {unixfs} from "@helia/unixfs";
	//import {CID} from "multiformats/cid";

	//NOTE: current browsers not yet implement ReadableStream[Symbol.asyncIterator]
	const rsWithAi = rs => { // supply ReadableStream[Symbol.asyncIterator]
	if (!(Symbol.asyncIterator in rs)) rs[Symbol.asyncIterator] = async function *() {
	const reader = rs.getReader();
	try {
	while (true) {
	const {value, done} = await reader.read();
	if (done) return;
	yield value;
	}
	} finally {
	reader.releaseLock();
	}
	};
	return rs;
	};

	//[1. start]
	const node1 = await helia.createHelia(); // default: use memory strores (non-persistent)
	const node2 = await helia.createHelia();
	const node1fs = unixfs(node1);
	const node2fs = unixfs(node2);
	console.log("[createHelia]");

	//[2. wait network established]
	//IMPORTANT: For call dial() each other, must await libp2p.getMultiaddrs().length > 0
	// - It is a big diffrence from js-ipfs behavior of `await createIpfs()`
	while (node1.libp2p.getMultiaddrs().length === 0) await new Promise(f => setTimeout(f, 500));
	while (node2.libp2p.getMultiaddrs().length === 0) await new Promise(f => setTimeout(f, 500));
	console.log("[libp2p.getMultiaddrs]1", node1.libp2p.getMultiaddrs().map(ma => `${ma}`));
	console.log("[libp2p.getMultiaddrs]2", node2.libp2p.getMultiaddrs().map(ma => `${ma}`));

	// connect nodes directly with dial()
	for (const ma of node2.libp2p.getMultiaddrs()) {
	try {
	//IMPORTANT: some of transports may fail to dial() directly
	await node1.libp2p.dial(ma);
	console.log(`[libp2p.dial] success: ${ma}`);
	break;
	} catch (error) {
	console.log(`[libp2p.dial] failed: ${ma}`);
	} // dial to other ma
	}

	//[3. feed content]
	// example data
	const blob = new Blob([new TextEncoder().encode("Hello World!")], {type: "text/plain;charset=utf-8"});
	console.log("[Blob]", blob);

	// publish blob as CID with addByteStream()
	const cid = await node1fs.addByteStream(rsWithAi(blob.stream()));
	//const cid = await node1fs.addBytes(new Uint8Array(await blob.arrayBuffer()));
	console.log("[unixfs.addByteStream]", cid);
	const cidStr = cid.toString();
	const cidAlt = CID.parse(cidStr);
	//NOTE: pins only accept when block data existed in node; cannot reserve pinning cid in advance
	const ret1 = await node1.pins.add(cidAlt); //NOTE: pins.add() not accept CID string
	console.log("[pins.add]", ret1);

	//[4. retrieve content]
	// NOTE: helia's pins needs stored blocks in blockstore (e.g. cannnot pin before stat()/ls()/cat())
	const stat = await node2fs.stat(cidStr);
	console.log("[unixfs.stat]", stat);
	const ret2 = await node2.pins.add(cidAlt); //NOTE: accept pins.add(cid) after stat(cid) successed
	console.log("[pins.add]", ret2);

	// get CID object from CID string with ls() from @helia/unixfs
	for await (const entry of node2fs.ls(cidStr)) {
	console.log("[unixfs.ls]", entry.cid);
	}

	// retrieve data with cat(cid or cid-string)
	const u8as = [];
	for await (const u8a of node2fs.cat(cidStr)) {
	console.log("[unixfs.cat]", u8a);
	u8as.push(u8a.slice()); //NOTE: create non shared Uint8Array instance with u8a.slice()
	//IMPORTANT: u8a returned maybe shared in helia impl, so it would crush when u8a.buffer is detached by some action
	// - ReadableStream controller.enqueue(u8a)
	// - postMessage(msg, [u8a.buffer])
	}
	console.log("[Blob.text]", await (new Blob(u8as).text()));

	//[5. stop]
	// stop only helia nodes; unixfs is just a wrapper
	console.log("[helia.stop]", await Promise.all([node1.stop(), node2.stop()]));