Using js-ipfs node in SharedWorker from ServiceWorker

In this example, you will find boilerplate code you can use to set up an IPFS node in a SharedWorker and use it from a ServiceWorker.

General Overview

src/main.js

Module is loaded in the main thread (DOM window) and is responsible for wiring all the pieces together:

1. Activates a SharedWorker that runs an IPFS node.
2. Registers a ServiceWorker to serve IPFS content from.
3. Listens to MessagePort requests from the ServiceWorker and responds back with a MessagePort of the SharedWorker, enabling it to interact with shaerd IPFS node.

src/worker.js

Module is loaded in the SharedWorker. It demonstrates how to setup the IPFS node such that it can be used in other browsing contexts.

src/service.js

Module is loaded in the ServiceWorker and responds to all the requests from the page. It recognizes four different request routes:

1. Routes /ipfs/..., /ipns/... are served html pages that:

• Contain a full page iframe that has an src derived from request path e.g.:

/ipfs/Qm...hash/file/name -> /view/Qm...hash/file/name

• src/main.js script loaded in it.

This way when request from /view/Qm..hash/file/name arrives ServiceWorker can obtain a MessagePort for the SharedWorker by requesting it from the iframe container.

2. Routes /view/ipfs/... and are served corresponding content from IPFS. On such request message is send to an iframe container (That is why /ipfs/... and /ipns/... routes served iframe and src/main.js), through which MessagePort for the SharedWorker is obtained and used to retrieve content from the shared IPFS node and served back.

   There is a stub for /view/ipns/... route, which is left as an excercise for the reader to fill.

3. All other routes are served by fetchging it from the network.

Before you start

First clone this repo, cd into the example directory and install the dependencies

git clone https://github.com/ipfs/js-ipfs.git
cd js-ipfs/examples/browser-service-worker
npm install

Running the example

Run the following command within this folder:

npm start

Now open your browser at http://localhost:3000

You should see the following:

If you navigate to the following address http://localhost:3000/ipfs/bafybeicqzoixu6ivztffjy4bktwxy6lxaxkvnavkya7kfgwyhx4bund2ga/ it should load a page from ipfs and appear as:

Run tests

npm test