npm package: @fluidframework/devtools-core
Description: Fluid Framework developer tools core functionality
Author: Microsoft and contributors
Latest version: 2.92.0

# @fluidframework/devtools-core

This library contains developer tools for use alongside the Fluid Framework.
It is used to power our associated [browser extension][browser-extension].

-   Chrome: <https://aka.ms/fluid/devtool/chrome>
-   Edge: <https://aka.ms/fluid/devtool/edge>

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## Using Fluid Framework libraries

When taking a dependency on a Fluid Framework library's public APIs, we recommend using a `^` (caret) version range, such as `^1.3.4`.
While Fluid Framework libraries may use different ranges with interdependencies between other Fluid Framework libraries,
library consumers should always prefer `^`.

If using any of Fluid Framework's unstable APIs (for example, its `beta` APIs), we recommend using a more constrained version range, such as `~`.

## Installation

To get started, install the package by running the following command:

```bash
npm i @fluidframework/devtools-core -D
```

## Importing from this package

This package leverages [package.json exports](https://nodejs.org/api/packages.html#exports) to separate its APIs by support level.
For more information on the related support guarantees, see [API Support Levels](https://fluidframework.com/docs/build/releases-and-apitags/#api-support-levels).

To access the `public` ([SemVer](https://semver.org/)) APIs, import via `@fluidframework/devtools-core` like normal.

To access the `beta` APIs, import via `@fluidframework/devtools-core/beta`.

To access the `alpha` APIs, import via `@fluidframework/devtools-core/alpha`.

## API Documentation

API documentation for **@fluidframework/devtools-core** is available at <https://fluidframework.com/docs/apis/devtools-core>.

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## Usage

The Devtools' API surface is designed to fit nicely into most application flows.

### Initialization

To initialize a devtools session for your container, call [`initializeDevtools`][initialize-devtools-docs].
This function accepts a `DevtoolsLogger` for receiving Fluid telemetry from your application, a list of initial Fluid
`Containers` to associate with the session, and (optionally) customized data visualization configurations for visualizing
`Container` data.

#### About the [`DevtoolsLogger`][devtools-logger-docs]

The `DevtoolsLogger` is an optional piece when calling `initializeDevtools` but it is strongly recommended that you use
it because several features in Fluid Devtools are powered by the telemetry that Fluid Framework generates, and this
logger is the way in which that telemetry gets into Fluid Devtools.

You can obtain a `DevtoolsLogger` by calling its constructor, and then should pass it to `initializeDevtools` _and_
to the `Loader` instance you'll use to create/load Containers as shown below.
This way the logger will receive all the telemetry generated by Fluid Framework in your application, and forward it to
Fluid Devtools as necessary.

```typescript
import { DevtoolsLogger, initializeDevtools } from "@fluidframework/devtools-core";

// Instantiate the logger
const devtoolsLogger = createDevtoolsLogger();

// Pass the logger when instantiating the Loader
const loader = new Loader({
	logger: devtoolsLogger,
	// Other necessary properties ...
});

// Use the Loader to create (and optionally, attach) a Container
const container = await loader.createDetachedContainer(/* params */);
await container.attach(/* params */);

// Initialize the Devtools passing the logger and your Container.
// The Container could be added later as well with devtools.registerContainerDevtools().
const devtools = initializeDevtools({
	logger: devtoolsLogger,
	initialContainers: [
		{
			container,
			containerKey: "My Container",
		},
	],
});
```

If you're working with `AzureClient` instead of lower-level APIs like the one described above, you probably want to
refer to the [@fluidframework/devtools package][devtools-package] instead of this one.

During local development the recommendation is that your application should receive the `DevtoolsLogger` instance _instead_
of any logger it would normally receive when deployed to a real environment, to avoid local development activity from
mixing with real telemetry.
If you still want to provide a real application logger and use the Fluid Devtools features that are powered by telemetry
at the same time, you can pass an existing logger to the `DevtoolsLogger` constructor and it will forward all telemetry
it receives to that logger as well:

```typescript
import { DevtoolsLogger } from "@fluidframework/devtools-core";

// Your application's logger
const yourApplicationLogger = getInstanceOfYourApplicationLogger();

const devtoolsLogger = createDevtoolsLogger(yourApplicationLogger);

// Pass devtoolsLogger to initializeDevtools() and to your application as described above
```

### Clean-up

The Devtools object is managed as a global singleton.
That singleton is automatically cleaned up prior to the Window's "unload" event.
So typical application flows likely won't need to worry about cleanup.
That said, if you wish to have tighter control over when the Devtools are torn down, you can simply call the `dispose` method on the handle returned by [initialization](#initialization).

## Contributing to the package

### Build

To build the package locally, first ensure you have run `pnpm install` from the root of the mono-repo.
Next, to build the code, run `npm run build` from the root of the mono-repo, or use [fluid-build](https://github.com/microsoft/FluidFramework/tree/main/build-tools/packages/build-tools#running-fluid-build-command-line) via `fluid-build -t build`.

-   Note: Once you have run a build from the root, assuming no other changes outside of this package, you may run `npm run build` directly within this directory for a faster build.
    If you make changes to any of this package's local dependencies, you will need to run a build again from the root before building again from directly within this package.

### Test

To run the tests, first ensure you have followed the [build](#build) steps above.
Next, run `npm run test` from a terminal within this directory.


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## Minimum Client Requirements

These are the platform requirements for the current version of Fluid Framework Client Packages.
These requirements err on the side of being too strict since within a major version they can be relaxed over time, but not made stricter.
For Long Term Support (LTS) versions this can require supporting these platforms for several years.

It is likely that other configurations will work, but they are not supported: if they stop working, we do not consider that a bug.
If you would benefit from support for something not listed here, file an issue and the product team will evaluate your request.
When making such a request please include if the configuration already works (and thus the request is just that it becomes officially supported), or if changes are required to get it working.

### Supported Runtimes

-   NodeJs ^20.10.0 except that we will drop support for it [when NodeJs 20 loses its upstream support on 2026-04-30](https://github.com/nodejs/release#release-schedule), and will support a newer LTS version of NodeJS (22) at least 1 year before 20 is end-of-life. This same policy applies to NodeJS 22 when it is end of life (2027-04-30).
    -   Running Fluid in a Node.js environment with the `--no-experimental-fetch` flag is not supported.
-   Modern browsers supporting the es2022 standard library: in response to asks we can add explicit support for using babel to polyfill to target specific standards or runtimes (meaning we can avoid/remove use of things that don't polyfill robustly, but otherwise target modern standards).

### Supported Tools

-   TypeScript 5.4:
    -   All [`strict`](https://www.typescriptlang.org/tsconfig) options are supported.
    -   [`strictNullChecks`](https://www.typescriptlang.org/tsconfig) is required.
    -   [Configuration options deprecated in 5.0](https://github.com/microsoft/TypeScript/issues/51909) are not supported.
    -   `exactOptionalPropertyTypes` is currently not fully supported.
        If used, narrowing members of Fluid Framework types types using `in`, `Reflect.has`, `Object.hasOwn` or `Object.prototype.hasOwnProperty` should be avoided as they may incorrectly exclude `undefined` from the possible values in some cases.
-   [webpack](https://webpack.js.org/) 5
    -   We are not intending to be prescriptive about what bundler to use.
        Other bundlers which can handle ES Modules should work, but webpack is the only one we actively test.

### Module Resolution

[`Node16`, `NodeNext`, or `Bundler`](https://www.typescriptlang.org/tsconfig#moduleResolution) resolution should be used with TypeScript compilerOptions to follow the [Node.js v12+ ESM Resolution and Loading algorithm](https://nodejs.github.io/nodejs.dev/en/api/v20/esm/#resolution-and-loading-algorithm).
Node10 resolution is not supported as it does not support Fluid Framework's API structuring pattern that is used to distinguish stable APIs from those that are in development.

### Module Formats

-   ES Modules:
    ES Modules are the preferred way to consume our client packages (including in NodeJs) and consuming our client packages from ES Modules is fully supported.
-   CommonJs:
    Consuming our client packages as CommonJs is supported only in NodeJS and only for the cases listed below.
    This is done to accommodate some workflows without good ES Module support.
    If you have a workflow you would like included in this list, file an issue.
    Once this list of workflows motivating CommonJS support is empty, we may drop support for CommonJS one year after notice of the change is posted here.

    -   Testing with Jest (which lacks [stable ESM support](https://jestjs.io/docs/ecmascript-modules) due to [unstable APIs in NodeJs](https://github.com/nodejs/node/issues/37648))

## Contribution Guidelines

There are many ways to [contribute](https://github.com/microsoft/FluidFramework/blob/main/CONTRIBUTING.md) to Fluid.

-   Participate in Q&A in our [GitHub Discussions](https://github.com/microsoft/FluidFramework/discussions).
-   [Submit bugs](https://github.com/microsoft/FluidFramework/issues) and help us verify fixes as they are checked in.
-   Review the [source code changes](https://github.com/microsoft/FluidFramework/pulls).
-   [Contribute bug fixes](https://github.com/microsoft/FluidFramework/blob/main/CONTRIBUTING.md).

Detailed instructions for working in the repo can be found in the [Wiki](https://github.com/microsoft/FluidFramework/wiki).

This project has adopted the [Microsoft Open Source Code of Conduct](https://opensource.microsoft.com/codeofconduct/).
For more information see the [Code of Conduct FAQ](https://opensource.microsoft.com/codeofconduct/faq/) or contact [opencode@microsoft.com](mailto:opencode@microsoft.com) with any additional questions or comments.

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](https://www.microsoft.com/trademarks).
Use of Microsoft trademarks or logos in modified versions of this project must not cause confusion or imply Microsoft sponsorship.

## Help

Not finding what you're looking for in this README? Check out [fluidframework.com](https://fluidframework.com/docs/).

Still not finding what you're looking for? Please [file an issue](https://github.com/microsoft/FluidFramework/wiki/Submitting-Bugs-and-Feature-Requests).

Thank you!

## 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](https://www.microsoft.com/en-us/legal/intellectualproperty/trademarks/usage/general).

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

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<!-- Links -->

[initialize-devtools-docs]: https://fluidframework.com/docs/apis/devtools-core#initializedevtools-function
[devtools-logger-docs]: https://fluidframework.com/docs/apis/devtools-core/devtoolslogger-class
[devtools-package]: https://www.npmjs.com/package/@fluidframework/devtools
[browser-extension]: https://github.com/microsoft/FluidFramework/tree/main/packages/tools/devtools/devtools-browser-extension