Installing an API client

You only need to install the API client package if you choose not to use the Gadget hosted frontend

Methods	Use cases
Direct script tag	High-traffic websites, CMS platforms, E-commerce sites
React	Use an external React frontend with your preferred code editor
Node module	Web applications with server-side rendering, non-React JS applications

Direct script tag

Gadget generates JavaScript code directly for your web frontend for straightforward integrations into websites. This <script/> tag method is the simplest and easiest way to get started using example-app's API.

html

1<script src="https://example-app.gadget.app/api/client/web.min.js"></script>
2<script>
3  // create a new instance of the Gadget client at the `api` global connected to the Development environment
4  window.api = new Gadget({
5    environment: "Development"
6  })
7</script>

Once the above script tags have been included, you can access api to start making API calls! The generated code is cached on Gadget's CDN and is safe to include directly on high-traffic web properties like a Shopify store or a WordPress blog. We recommend this method of installation for websites when possible, as the client will update without you having to make changes to your code or manually sync with Gadget.

JavaScript

const results = await api.query(`
  query GetSomeData {
    # start writing GraphQL queries!
  }
`);

Using your Development environment's direct script tag

If you are using a direct script tag to test on your Development environment, make sure to use your app's --development url for the script tag's src param.

Example

html

<script src="https://example-app--development.gadget.app/api/client/web.min.js"></script>

React

To use your Gadget client with React, you must install both React and the React bindings.

npm install @gadgetinc/react @gadget-client/example-app

yarn add @gadgetinc/react @gadget-client/example-app

If you are using the Gadget-hosted React frontend, these packages are already installed! You don't need to re-add them.

Creating the client for React apps

Once your @gadget-client/example-app package has been installed, create an instance of the Client class in a shared file somewhere:

This client will be shared by all your React components, so it's best to put this code outside any particular component, or within one of your root components where it can be shared. Be sure to select the appropriate authentication mode for your use case.

web/api.js

JavaScript

import { Client } from "@gadget-client/example-app";
export const api = new Client({
  authenticationMode: { browserSession: true },
});

If you are using Next.js, or other server-side rendering environments, using browserSession authentication mode will not work, as server-side environments don't support localStorage. Instead, instantiate the client without specifying an authentication mode.

JavaScript

export const api = new Client();

This will default to using the anonymous authentication mode on the server, and the browserSession authentication mode on the client.

Providing the React client

Once your client is installed and set up, you must provide an instance of your client to your React components using the Gadget React provider. Instantiate the client using the instructions above, and then pass it to the api prop of the provider.

JavaScript

1import { Provider } from "@gadgetinc/react";
2import { api } from "shared/api";
3const App = () => (
4  <Provider api={api}>
5    <YourRoutes />
6  </Provider>
7);

You must re-install the Gadget client if you make breaking changes to the application after installing the client. See Client regeneration for more details.

Node module

To work with the Gadget API server-side from node.js, or to include generated Gadget code in a larger product with a JavaScript bundler like Webpack or Parcel, you can install the npm module for example-app. Installing the example-app API client works just like any other NPM package Gadget, and works with any NPM-compatible package manager.

This installation method works by installing the package from Gadget's own npm registry, where we host, version, and update your API client.

To install the example-app node package, register the Gadget NPM registry for the @gadget-client package scope:

terminal

npm config set @gadget-client:registry https://registry.gadget.dev/npm

Then, install the example-app client package using your package manager:

npm install @gadget-client/example-app

yarn add @gadget-client/example-app

As you make changes to example-app, Gadget will publish new versions of your API client to its NPM registry. See Client Regeneration for more details on when updates are necessary.

You must register the Gadget npm registry in all environments where you want to use this package, which would include production systems, continuous integration environments, or build steps like Vercel or Netlify's static site builders. This can be done using the above npm config command, or by writing out an .npmrc file in those environments that points to Gadget for the @gadget-client scope.

To indicate to hosting platforms where to find the @gadget-client/example-app package, create an .npmrc file in the web/frontend directory with the following content:

web/frontend/.npmrc

registry=https://registry.npmjs.org/
@gadget-client:registry=https://registry.gadget.dev/npm

After installation, the client module can be required and a client instance created:

JavaScript

import { Client } from "@gadget-client/example-app";
export const api = new Client();

The api object is now ready for use!

JavaScript

const results = api.query(`
  query GetSomeData {
    # start writing GraphQL queries!
  }
`);

Gadget also makes a tarball of the latest version of the API client available for download.

Tarball Endpoint

https://example-app--development.gadget.app/api/client/tarball

By default, the API Client will not have permission to access data within your application. You can use API Key authentication for server-side apps or Browser Session authentication for client side apps to grant a client access.

Connecting to a specific environment

Gadget backend apps support two different versions of the application: a Development version for developers constructing and testing their application, and a Production version for end users. The API client can be configured to connect to either environment by passing the environment option to the client constructor.

For example, we can always connect to the Development environment by passing the string "Development" to the environment option:

JavaScript

import { Client } from "@gadget-client/example-app";
export const api = new Client({
  environment: "Development",
});
// all API calls will be made to the Development environment

You can also explicitly connect to the Production environment by passing the string "Production" to the environment option:

JavaScript

import { Client } from "@gadget-client/example-app";
export const api = new Client({
  environment: "Production",
});
// all API calls will be made to the Production environment

or you can select which environment to connect to based on an environment variable

JavaScript

import { Client } from "@gadget-client/example-app";
export const api = new Client({
  environment: process.env["IS_PRODUCTION"] == "true" ? "Production" : "Development",
});

By default if no environment is specified the client will set the environment based on NODE_ENV if it is set.

Type safety

The default TypeScript types are included in the example-app client package, requiring no additional installation steps to utilize them.

The example-app client ensures comprehensive type safety for high-level JavaScript functions like find and findMany, providing reliable types for API requests and responses. When using the select option to retrieve specific fields, the client maps the selected fields to the GraphQL schema, returning an object with the chosen fields and their correct types, as demonstrated in this TypeScript example fetching the id and name of a User model.

TypeScript

1const users = await api.user.findMany({ select: { id: true, name: true } });
2
3console.log(users[0].id);
4// will typecheck just fine as the type `string`, and log an ID string for the user
5
6console.log(users[0].name);
7// will typecheck just fine as the type of the `name` field as set in the Gadget Editor, and log the value
8
9console.log(users[0].email);
10// will _fail_ the typecheck, as the `email` key was not included in the `select` option

Client regeneration

The API client source code changes as you make changes to your Gadget backend.

Because the web clients are generated on-demand, we recommend using these clients where possible. By sourcing it directly as a <script/> tag, your browser will fetch the most up to date code each time a page loads, and you'll always be working with a client guaranteed to work with the current API for the application. To preserve this fast refresh behavior, it is best to not cache the client with other infrastructure (like a proxy), or to save it to disk.

Updating the npm package

Gadget's npm registry will publish new versions of your package as changes are made to your Gadget app. You must install the new version of the API client package locally to reflect changes made in the Gadget editor. If a new model is added or removed, it will be available in the generated clients right away, but you need to update your local dependency version to fetch these changes.

To upgrade using npm, run:

Update to latest version with npm

terminal

npm install @gadget-client/example-app@latest

To upgrade using yarn, run:

Update to latest version with yarn

terminal

yarn add @gadget-client/example-app@latest

If the package is being used from a Gadget frontend with a Shopify Connection set-up, it does not need to be updated as it always applys the latest version.

Updating to only the latest production version

Upgrading to the @latest version of the npm package will install the latest version for the Development environment. To upgrade to the latest version of the Production environment only, you can install the @latest-production version. This version of the API client will only reflect changes that have been deployed to Production, and will not show changes that are in Development but not yet deployed.

To upgrade to only the latest deployed changes using npm, run:

Update to most recent deployed changes with npm

terminal

npm install @gadget-client/example-app@latest-production

To upgrade to only the latest deployed changes using npm, run:

Update to most recent deployed changes with yarn

terminal

yarn add @gadget-client/example-app@latest-production

Once changes are deployed using the Deploy button, the @latest and @latest-production version of the packages will match.

Best effort functionality

If your client version is out of date, that version still makes a best effort to continue to work with new versions of the data model and GraphQL schema. If a breaking change is made however, the client may try to make requests which no longer work. This can always be remedied by updating any cached source code using npm or yarn, or by copying new files sourced from Gadget's web.js endpoint.

The following changes will break an out of date example-app client and cause it to issue invalid requests:

changing a model's apiIdentifier
changing an action's apiIdentifier
removing an action
removing a model completely