Swarm.js

This library allows you to interact with the Swarm network from JavaScript.

Getting started

1. Install

   npm install swarm-js

2. Import

   // Loads the Swarm API pointing to the official gateway
   const swarm = require("swarm-js").at("http://swarm-gateways.net");

Examples

Uploads

• With JSON:

  • Raw data:

    const file = "test file"; // could also be an Uint8Array of binary data
    swarm.upload(file).then(hash => {
      console.log("Uploaded file. Address:", hash);
    })

  • Directory:

    To upload a directory, just call swarm.upload(directory), where directory is an object mapping paths to entries, those containing a mime-type and the data (Uint8Array or UTF-8 String).

    const dir = {
      "/foo.txt": {type: "text/plain", data: "file 0"},
      "/bar.txt": {type: "text/plain", data: "file 1"}
    };
    swarm.upload(dir).then(hash => {
      console.log("Uploaded directory. Address:", hash);
    });

• From disk:

  • On Node.js:

    swarm.upload({
      path: "/path/to/thing",      // path to data / file / directory
      kind: "directory",           // could also be "file" or "data"
      defaultFile: "/index.html"}) // optional, and only for kind === "directory"
      .then(console.log)
      .catch(console.log);

  • On browsers:

    // only works inside an event
    document.onClick = function() {
      swarm.upload({pick: "file"}) // could also be "directory" or "data"
        .then(alert);
    };

Downloads

• With JSON:

  • Raw data:

    const fileHash = "a5c10851ef054c268a2438f10a21f6efe3dc3dcdcc2ea0e6a1a7a38bf8c91e23";
    swarm.download(fileHash).then(array => {
      console.log("Downloaded file:", swarm.toString(array));
    });

  • Directory:

    const dirHash = "7e980476df218c05ecfcb0a2ca73597193a34c5a9d6da84d54e295ecd8e0c641";
    swarm.download(dirHash).then(dir => {
      console.log("Downloaded directory:");
      for (let path in dir) {
        console.log("-", path, ":", dir[path].data.toString());
      }
    });

• To disk:

  • On Node.js:

    swarm.download("DAPP_HASH", "/target/dir")
      .then(path => console.log(`Downloaded DApp to ${path}.`))
      .catch(console.log);

  • On browser:

    (Just link the Swarm URL.)

SwarmHash

console.log(swarm.hash("unicode string áéíóú λ"));
console.log(swarm.hash("0x41414141"));
console.log(swarm.hash([65, 65, 65, 65]));
console.log(swarm.hash(new Uint8Array([65, 65, 65, 65])));

More

For more examples, check out examples.