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Setting up the Golem JS SDK

Setting up the Golem JavaScript SDK

⚠️

If the project was created with golem-cli new, it already has the Golem JavaScript SDK set up and these steps can be ignored.

The Golem JavaScript SDK is the same as the Golem TypeScript SDK. The published SDK is usable from JavaScript, as it is bundled as JavaScript.

If setting up the Golem JavaScript SDK (opens in a new tab) manually, the following steps are required:

Create a new project

npm init

Ensure ESM is enabled

In your package.json file, ensure the type is set to module.

package.json
{
  "type": "module"
}

Install Dev Dependencies

The Golem JavaScript SDK currently relies on forked versions of jco (opens in a new tab) and componentize-js (opens in a new tab).

npm install --save-dev @golemcloud/componentize-js @golemcloud/golem-ts @golemcloud/jco @rollup/plugin-node-resolve@^15.2.3 rollup@^4.18.0

Add Rollup Config: rollup.config.mjs

To silence rollup warnings, add WIT imports to the external array.

rollup.config.mjs
import resolve from "@rollup/plugin-node-resolve"
 
export default {
  input: "src/main.js",
  output: {
    file: "out/main.js",
    format: "esm",
  },
  external: [
    "golem:api/host@0.2.0",
    "golem:rpc/types@0.1.0",
    "wasi:blobstore/blobstore",
    "wasi:blobstore/container",
    "wasi:cli/environment@0.2.0",
    "wasi:clocks/wall-clock@0.2.0",
    "wasi:clocks/monotonic-clock@0.2.0",
    "wasi:filesystem/preopens@0.2.0",
    "wasi:filesystem/types@0.2.0",
    "wasi:http/types@0.2.0",
    "wasi:http/outgoing-handler@0.2.0",
    "wasi:io/error@0.2.0",
    "wasi:io/poll@0.2.0",
    "wasi:io/streams@0.2.0",
    "wasi:keyvalue/eventual-batch@0.1.0",
    "wasi:keyvalue/eventual@0.1.0",
    "wasi:logging/logging",
    "wasi:random/random@0.2.0",
    "wasi:random/insecure@0.2.0",
    "wasi:random/insecure-seed@0.2.0",
    "wasi:sockets/ip-name-lookup@0.2.0",
    "wasi:sockets/instance-network@0.2.0",
  ],
  plugins: [resolve()],
}

Add scripts to package.json

package.json
{
  "scripts": {
    "build": "rollup --config",
    "componentize": "npm run build && jco componentize -w wit -o out/component_name.wasm out/main.js",
    "clean": "rm -rf out src/generated"
  }
}
  • build - Packages the Javascript into a single file.
  • componentize - Bundles the Javascript into a WebAssembly module.
  • clean - Cleans up the project by removing the generated files.

Verify package.json

Ensure the scripts and devDependencies sections are correct (versions may differ).

package.json
{
  "type": "module",
  "scripts": {
    "stub": "jco stubgen wit -o src/generated",
    "build": "rollup --config",
    "componentize": "npm run stub && npm run build && jco componentize -w wit -o out/component_name.wasm out/main.js",
    "clean": "rm -rf out src/generated"
  },
  "devDependencies": {
    "@golemcloud/componentize-js": "0.10.5-golem.3",
    "@golemcloud/golem-ts": "0.2.0",
    "@golemcloud/jco": "1.4.4-golem.1",
    "@rollup/plugin-node-resolve": "^15.2.3",
    "rollup": "^4.18.0"
  }
}

Add all the supported WIT files into the project

The project's wit/deps directory must contain all the WIT files from the golem-wit (opens in a new tab) repository.

Either clone the repository and copy the wit/deps directory into your project, or run the following command to download the WIT files:

curl -L https://github.com/golemcloud/golem-wit/archive/refs/heads/main.zip | tar -xvf- -C . --strip-components=2 "golem-wit-main/wit/deps" && mkdir -p ./wit/deps && mv deps/* ./wit/deps/ && rm -rf deps/

The resulting directory structure should look like this:

    • main.wit

    • Importing WITs into the component's world:

    If the project's WIT file was like this:

    package golem:demo;
 
world ts-example {
  export api;
}

    Modify it in the following way:

    package golem:demo;
 
world ts-example {
  import golem:api/host@0.2.0;
  import golem:rpc/types@0.1.0;
 
  import wasi:blobstore/blobstore;
  import wasi:blobstore/container;
  import wasi:cli/environment@0.2.0;
  import wasi:clocks/wall-clock@0.2.0;
  import wasi:clocks/monotonic-clock@0.2.0;
  import wasi:filesystem/preopens@0.2.0;
  import wasi:filesystem/types@0.2.0;
  import wasi:http/types@0.2.0;
  import wasi:http/outgoing-handler@0.2.0;
  import wasi:io/error@0.2.0;
  import wasi:io/poll@0.2.0;
  import wasi:io/streams@0.2.0;
  import wasi:keyvalue/eventual-batch@0.1.0;
  import wasi:keyvalue/eventual@0.1.0;
  import wasi:logging/logging;
  import wasi:random/random@0.2.0;
  import wasi:random/insecure@0.2.0;
  import wasi:random/insecure-seed@0.2.0;
  import wasi:sockets/ip-name-lookup@0.2.0;
  import wasi:sockets/instance-network@0.2.0;
 
  export api;
}
    Next StepsHTTP client