Use it in your app

The CLI builds and ships the SDK. Your application is what actually calls it. This page gets the package installed and a client running; run an operation is the call itself. The generated SDK is an npm package, a Python package, or a Go module. It opens a shared gRPC connection to your Fused deployment for physical service calls. Hosted Unified App calls use Fused’s HTTP endpoint.

Install it

app download <name@version> extracts the package to fused-sdks/<name>. The app apply --download convenience form does the same after an explicit apply. The package is not published anywhere, so install it from that path.

cd fused-sdks/support-sdk
npm install && npm run build

cd ../../
npm install ./fused-sdks/support-sdk

pip install ./fused-sdks/support-sdk

# Run from your application's existing Go module to use the downloaded SDK locally.
FUSED_SDK_MODULE=$(cd ./fused-sdks/support-sdk && go list -m)
go mod edit -require="${FUSED_SDK_MODULE}@v0.0.0"
go mod edit -replace="${FUSED_SDK_MODULE}=./fused-sdks/support-sdk"

Go requires version 1.24 or later. After importing the generated module in your application, run go mod tidy. Use the exact module path from its go.mod or generated README; it includes a suffix derived from the SDK name. Vendor the package, or publish it to your own private registry. The generated package.json, pyproject.toml, or go.mod records its package identity.

Create the client

One client, one gRPC channel, shared by every service on it.

import { FusedSDK } from 'support-sdk';

const sdk = new FusedSDK({
  grpcUrl: process.env.FUSED_ENGINE_GRPC_URL,
  token: process.env.FUSED_APP_TOKEN!,
});

import os
from fused.support_sdk import FusedSDK

sdk = FusedSDK({
    "grpc_url": os.environ["FUSED_ENGINE_GRPC_URL"],
    "token": os.environ["FUSED_APP_TOKEN"],
})

package main

import (
	"context"
	"log"
	"os"

	fusedsdk "fused.local/support-sdk-01e60d53"
)

// main opens one authenticated client for the generated support-sdk package.
func main() {
	ctx := context.Background()
	sdk, err := fusedsdk.New(ctx, fusedsdk.Config{
		EngineURL: os.Getenv("FUSED_ENGINE_GRPC_URL"),
		Token:     os.Getenv("FUSED_APP_TOKEN"),
	})
	// Do not use the client unless its immutable app handshake succeeds.
	if err != nil {
		log.Fatal(err)
	}
	defer sdk.Close(ctx)

	// Call the service methods listed in the generated README here.
}

token (Token in Go) is the execution token from apply. In TypeScript and Python, the optional gRPC address falls back to FUSED_ENGINE_GRPC_URL, then FUSED_ENGINE_URL, then localhost. Set it explicitly; the fallback has a trap. The Go import above is for an SDK named support-sdk; replace it with the module path in your generated go.mod. Config.EngineURL takes Fused’s gRPC address. Set Config.HTTPURL to the HTTP address when calling hosted Unified Apps.

Shut it down

The channel is long-lived, so close it when your process does. Go uses sdk.Close(ctx), as shown by the deferred call above.

process.on('SIGTERM', () => sdk.close());

async with FusedSDK(config) as sdk:
    ...

# or explicitly
await sdk.close()

Run an operation

The call itself: what you pass, what comes back, and what can go wrong.

Receive events

The other half of your application code: reacting to what the provider sends you.

Get Started

Guides

Advanced

Reference

Use it in your app

Install it

Create the client

Shut it down

Run an operation

Receive events

​Install it

​Create the client

​Shut it down

Run an operation

Receive events

Install it

Create the client

Shut it down