The Aqueduct is a library for building Fluid objects and Fluid containers within the Fluid Framework. Its goal is to provide a thin base layer over the existing Fluid Framework interfaces that allows developers to get started quickly.

Fluid object development

Fluid object development consists of developing the data object and the corresponding data object factory. The data object defines the logic of your Fluid object, whereas the data object factory defines how to initialize your object.

Data object development

DataObject and PureDataObject are the two base classes provided by the library.

DataObject

The DataObject class extends PureDataObject and provides the following additional functionality:

A root SharedDirectory that makes creating and storing distributed data structures and objects easy.
Blob storage implementation that makes it easier to store and retrieve blobs.

Note: Most developers will want to use the DataObject as their base class to extend.

PureDataObject

PureDataObject provides the following functionality:

Basic set of interface implementations to be loadable in a Fluid container.
Functions for managing the Fluid object lifecycle.
- initializingFirstTime(props: S) - called only the first time a Fluid object is initialized and only on the first client on which it loads.
- initializingFromExisting() - called every time except the first time a Fluid object is initialized; that is, every time an instance is loaded from a previously created instance.
- hasInitialized() - called every time after initializingFirstTime or initializingFromExisting executes
Helper functions for creating and getting other data objects in the same container.

Note: You probably don't want to inherit from this data object directly unless you are creating another base data object class. If you have a data object that doesn't use distributed data structures you should use Container Services to manage your object.

DataObject example

In the below example we have a simple data object, Clicker, that will render a value alongside a button the the page. Every time the button is pressed the value will increment. Because this data object renders to the DOM it also extends IFluidHTMLView.

export class Clicker extends DataObject implements IFluidHTMLView {
    public static get Name() { return "clicker"; }

    public get IFluidHTMLView() { return this; }

    private _counter: SharedCounter | undefined;

    protected async initializingFirstTime() {
        const counter = SharedCounter.create(this.runtime);
        this.root.set("clicks", counter.handle);
    }

    protected async hasInitialized() {
        const counterHandle = this.root.get<IFluidHandle<SharedCounter>>("clicks");
        this._counter = await counterHandle.get();
    }

    public render(div: HTMLElement) {
        ReactDOM.render(
            <CounterReactView counter={this.counter} />,
            div,
        );
        return div;
    }

    private get counter() {
        if (this._counter === undefined) {
            throw new Error("SharedCounter not initialized");
        }
        return this._counter;
    }
}

DataObjectFactory development

The DataObjectFactory is used to create a Fluid object and to initialize a data object within the context of a Container. The factory can live alongside a data object or within a different package. The DataObjectFactory defines the distributed data structures used within the data object as well as any Fluid objects it depends on.

The Aqueduct offers a factory for each of the data objects provided.

More details

DataObjectFactory example

In the below example we build a DataObjectFactory for the Clicker example above. To build a DataObjectFactory, we need to provide factories for the distributed data structures we are using inside of our DataObject. In the above example we store a handle to a SharedCounter in this.root to track our "clicks". The DataObject comes with the SharedDirectory (this.root) already initialized, so we just need to add the factory for SharedCounter.

export const ClickerInstantiationFactory = new DataObjectFactory({
	type: Clicker.Name,
	ctor: Clicker,
	sharedObjects: [SharedCounter.getFactory()],
});

This factory can then create Clickers when provided a creating instance context.

const myClicker = ClickerInstantiationFactory.createInstance(this.context) as Clicker;

Providers in data objects

The this.providers object on PureDataObject is initialized in the constructor and is generated based on Providers provided by the Container. To access a specific provider you need to:

Define the type in the generic on PureDataObject/DataObject
Add the symbol to your factory (see DataObjectFactory Example below)

In the below example we have an IFluidUserInfo interface that looks like this:

interface IFluidUserInfo {
	readonly userCount: number;
}

On our example we want to declare that we want the IFluidUserInfo Provider and get the userCount if the Container provides the IFluidUserInfo provider.

export class MyExample extends DataObject<IFluidUserInfo> {
    protected async initializingFirstTime() {
        const userInfo = await this.providers.IFluidUserInfo;
        if(userInfo) {
            console.log(userInfo.userCount);
        }
    }
}

// Note: we have to define the symbol to the IFluidUserInfo that we declared above. This is compile time checked.
export const ClickerInstantiationFactory = new DataObjectFactory({
    type: Clicker.Name
    ctor: Clicker,
    optionalProviders: { IFluidUserInfo }, // Provider Symbols see below
});

Container development

A Container is a collection of data objects and functionality that produce an experience. Containers hold the instances of data objects as well as defining the data objects that can be created within the Container. Because of this data objects cannot be consumed except for when they are within a Container.

The Aqueduct library provides the ContainerRuntimeFactoryWithDefaultDataStore that enables you as a container developer to:

Define the registry of data objects that can be created
Declare the default data object
Use provider entries
Declare Container level Request Handlers

Container object example

In the below example we will write a Container that exposes the above Clicker using the Clicker Factory. You will notice below that the Container developer defines the registry name (data object type) of the Fluid object. We also pass in the type of data object we want to be the default. The default data object is created the first time the Container is created.

export fluidExport = new ContainerRuntimeFactoryWithDefaultDataStore(
  ClickerInstantiationFactory.type, // Default data object type
  ClickerInstantiationFactory.registryEntry, // Fluid object registry
  [], // Provider Entries
  [], // Request Handler Routes
);

Container-level request handlers

You can provide custom request handlers to the container. These request handlers are injected after system handlers but before the DataObject get function. Request handlers allow you to intercept requests made to the container and return custom responses.

Consider a scenario where you want to create a random color generator. I could create a RequestHandler that when someone makes a request to the Container for {url:"color"} will intercept and return a custom IResponse of { status:200, type:"text/plain", value:"blue"}.

We use custom handlers to build the Container Services pattern.

Minimum Client Requirements

Fluid Framework client libraries support the platforms in this document. These requirements are intentionally restrictive. Within a major version series, we can relax these requirements, but we cannot make them stricter. For a Long Term Support (LTS) version, we might need to support these platforms for several years.

Other configurations can work, but Fluid Framework does not support them. If an unsupported configuration stops working, we do not classify this as a bug. To request support for a configuration that is not listed, file an issue. The product team will evaluate your request. In the issue, specify the current status of the configuration:

The configuration works but needs official support.
The configuration does not work and requires changes.

Supported Runtimes

Fluid Framework supports Node.js versions 22 and 24 while they receive upstream support.
- Fluid Framework will stop support for version 22 when upstream support ends on 2027-04-30.
- Fluid Framework does not support Node.js with the --no-experimental-fetch flag.
Fluid Framework supports modern browsers that support the ES2022 standard library.

Supported Tools

TypeScript 6.0:
- Fluid Framework supports all strict options.
- Set the build targets (lib, target) to ES2022 or later.
- Enable strictNullChecks.
- Fluid Framework does not support configuration options deprecated in TypeScript 6.0.
- Fluid Framework does not fully support exactOptionalPropertyTypes. If you enable this option, do not use in, Reflect.has, Object.hasOwn, or Object.prototype.hasOwnProperty to narrow members of Fluid Framework types. These methods can incorrectly exclude undefined from the possible values.
webpack 5
- We do not require a specific bundler. Other bundlers that handle ES Modules can work, but we actively test only webpack.

Module Resolution

In TypeScript compilerOptions, use Node16, Node20, NodeNext, or Bundler module resolution. These settings follow the Node.js v12+ ESM Resolution and Loading algorithm.

Do not use Node10 module resolution.

Module Formats

ES Modules: Use ES Modules to consume Fluid Framework client packages, including in Node.js.
CommonJS: Fluid Framework does not officially support CommonJS in version 3.0 or later.

Contribution Guidelines

You can contribute to Fluid Framework in these ways:

Answer questions in GitHub Discussions.
Submit bug reports and help verify fixes.
Review source code changes.
Contribute bug fixes.

For detailed instructions, read the repo documentation.

This project follows the Microsoft Open Source Code of Conduct. For more information, read the Code of Conduct frequently asked questions. For questions or comments, contact opencode@microsoft.com.

This project may contain Microsoft trademarks or logos for Microsoft projects, products, or services. Use of these trademarks or logos must follow Microsoft’s Trademark & Brand Guidelines. Use of Microsoft trademarks or logos in modified versions of this project must not cause confusion or imply Microsoft sponsorship.

Help

Read the Fluid Framework documentation for information about Fluid Framework concepts and APIs.

To request information that the documentation does not contain, create an issue.

Trademark

This project may contain Microsoft trademarks or logos for Microsoft projects, products, or services.

Use of these trademarks or logos must follow Microsoft's Trademark & Brand Guidelines.

Use of Microsoft trademarks or logos in modified versions of this project must not cause confusion or imply Microsoft sponsorship.