medusa-store/www/apps/resources/app/js-sdk/page.mdx

import { CodeTabs, CodeTab, Table } from "docs-ui"

export const metadata = {
  title: `Medusa JS SDK`,
}

# {metadata.title}

In this documentation, you'll learn how to install and use Medusa's JS SDK.

## What is Medusa JS SDK?

Medusa's JS SDK is a library to easily send requests to your Medusa application. You can use it in your admin customizations or custom storefronts.

---

## How to Install Medusa JS SDK?

The Medusa JS SDK is available in your Medusa application by default. So, you don't need to install it before using it in your admin customizations.

To install the Medusa JS SDK in other projects, such as a custom storefront, run the following command:

```bash npm2yarn
npm install @medusajs/js-sdk@latest @medusajs/types@latest
```

You install two libraries:

- `@medusajs/js-sdk`: the Medusa JS SDK.
- `@medusajs/types`: Medusa's types library, which is useful if you're using TypeScript in your development.

---

## Setup JS SDK

In your project, create the following `config.ts` file:

<Note>

For admin customizations, create this file at `src/admin/lib/config.ts`.

</Note>

<CodeTabs group="sdk-project">
  <CodeTab label="Admin" value="admin">

```ts title="src/admin/lib/config.ts"
import Medusa from "@medusajs/js-sdk"

export const sdk = new Medusa({
  baseUrl: "http://localhost:9000",
  debug: process.env.NODE_ENV === "development",
  auth: {
    type: "session",
  },
})
```

  </CodeTab>
  <CodeTab label="Storefront" value="storefront">

```ts title="config.ts"
import Medusa from "@medusajs/js-sdk"

let MEDUSA_BACKEND_URL = "http://localhost:9000"

if (process.env.NEXT_PUBLIC_MEDUSA_BACKEND_URL) {
  MEDUSA_BACKEND_URL = process.env.NEXT_PUBLIC_MEDUSA_BACKEND_URL
}

export const sdk = new Medusa({
  baseUrl: MEDUSA_BACKEND_URL,
  debug: process.env.NODE_ENV === "development",
  publishableKey: process.env.NEXT_PUBLIC_MEDUSA_PUBLISHABLE_KEY,
})
```

  </CodeTab>
</CodeTabs>

### JS SDK Configurations

The `Medusa` initializer accepts as a parameter an object with the following properties:

<Table>
  <Table.Header>
    <Table.Row>
      <Table.HeaderCell>Property</Table.HeaderCell>
      <Table.HeaderCell className="w-2/5">Description</Table.HeaderCell>
      <Table.HeaderCell>Default</Table.HeaderCell>
    </Table.Row>
  </Table.Header>
  <Table.Body>
    <Table.Row>
      <Table.Cell>

      `baseUrl`

      </Table.Cell>
      <Table.Cell>

      A required string indicating the URL to the Medusa backend.

      </Table.Cell>
      <Table.Cell>

      \-

      </Table.Cell>
    </Table.Row>
    <Table.Row>
      <Table.Cell>

      `publishableKey`

      </Table.Cell>
      <Table.Cell>

      A string indicating the publishable API key to use in the storefront. You can retrieve it from the Medusa Admin.

      This is required for storefront applications. Otherwise, all requests will fail.

      </Table.Cell>
      <Table.Cell>

      \-

      </Table.Cell>
    </Table.Row>
    <Table.Row>
      <Table.Cell>

      `auth.type`

      </Table.Cell>
      <Table.Cell>

      A string that specifies the user authentication method to use.

      Possible types are:

      - `session`: The user is authenticated with a cookie session.
      - `jwt`: The user is authenticated with a JWT token that's passed in the Bearer authorization header.

      </Table.Cell>
      <Table.Cell>

      \-

      </Table.Cell>
    </Table.Row>
    <Table.Row>
      <Table.Cell>

      `auth.jwtTokenStorageKey`

      </Table.Cell>
      <Table.Cell>

      A string that, when `auth.type` is `jwt`, specifies the key of the JWT token in the storage specified in the `auth.jwtTokenStorageMethod` configuration.

      </Table.Cell>
      <Table.Cell>

      `medusa_auth_token`

      </Table.Cell>
    </Table.Row>
    <Table.Row>
      <Table.Cell>

      `auth.jwtTokenStorageMethod`

      </Table.Cell>
      <Table.Cell>

      A string that, when `auth.type` is `jwt`, specifies where the JWT token is stored. Possible values are:

      - `local` for the Local Storage.
      - `session` for the Session Storage.
      - `memory` to store it within the SDK for the current application's runtime.

      </Table.Cell>
      <Table.Cell>

      `local`

      </Table.Cell>
    </Table.Row>
    <Table.Row>
      <Table.Cell>

      `globalHeaders`

      </Table.Cell>
      <Table.Cell>

      An object of key-value pairs indicating headers to pass in all requests, where the key indicates the name of the header field.

      </Table.Cell>
      <Table.Cell>

      \-

      </Table.Cell>
    </Table.Row>
    <Table.Row>
      <Table.Cell>

      `apiKey`

      </Table.Cell>
      <Table.Cell>

      A string indicating the admin user's API key. If specified, it's used to send authenticated requests.

      </Table.Cell>
      <Table.Cell>

      \-

      </Table.Cell>
    </Table.Row>
    <Table.Row>
      <Table.Cell>

      `debug`

      </Table.Cell>
      <Table.Cell>

      A boolean indicating whether to show debug messages of requests sent in the console. This is useful during development.

      </Table.Cell>
      <Table.Cell>

      `false`

      </Table.Cell>
    </Table.Row>
    <Table.Row>
      <Table.Cell>

      `logger`

      </Table.Cell>
      <Table.Cell>

      Replace the logger used by the JS SDK to log messages. The logger must be a class or object having the following methods:

      - `error`: A function that accepts an error message to log.
      - `warn`: A function that accepts a warning message to log.
      - `info`: A function that accepts an info message to log.
      - `debug`: A function that accepts a debug message to log.

      </Table.Cell>
      <Table.Cell>

      JavaScript's [console](https://developer.mozilla.org/en-US/docs/Web/API/console) is used by default.

      </Table.Cell>
    </Table.Row>
  </Table.Body>
</Table>

---

## Medusa JS SDK Tips

### Use Tanstack (React) Query in Admin Customizations

In admin customizations, use [Tanstack Query](https://tanstack.com/query/latest) with the JS SDK to send requests to custom or existing API routes.

Tanstack Query is installed by default in your Medusa application.

Use the [configured SDK](#setup-js-sdk) with the [useQuery](https://tanstack.com/query/latest/docs/framework/react/reference/useQuery#usequery) Tanstack Query hook to send `GET` requests, and [useMutation](https://tanstack.com/query/latest/docs/framework/react/reference/useMutation#usemutation) hook to send `POST` or `DELETE` requests.

For example:

<CodeTabs group="query-type">
  <CodeTab label="Query" value="query">

export const queryHighlights = [
  ["8", "useQuery", "Use Tanstack Query's `useQuery` to send a `GET` request."],
  ["9", "sdk.admin.product.list", "Use the SDK to send the request."],
  ["10", "queryKey", "Specify the key used to cache data."]
]

```tsx title="src/admin/widgets/product-widget.ts"
import { defineWidgetConfig } from "@medusajs/admin-sdk"
import { Button, Container } from "@medusajs/ui"
import { useQuery } from "@tanstack/react-query"
import { sdk } from "../lib/config"
import { DetailWidgetProps, HttpTypes } from "@medusajs/framework/types"

const ProductWidget = () => {
  const { data, isLoading } = useQuery({
    queryFn: () => sdk.admin.product.list(),
    queryKey: ["products"]
  })
  
  return (
    <Container className="divide-y p-0">
      {isLoading && <span>Loading...</span>}
      {data?.products && (
        <ul>
          {data.products.map((product) => (
            <li key={product.id}>{product.title}</li>
          ))}
        </ul>
      )}
    </Container>
  )
}

export const config = defineWidgetConfig({
  zone: "product.list.before",
})

export default ProductWidget
```

  </CodeTab>
  <CodeTab label="Mutation" value="mutation">

```tsx title="src/admin/widgets/product-widget.ts"
import { defineWidgetConfig } from "@medusajs/admin-sdk"
import { Button, Container } from "@medusajs/ui"
import { useMutation } from "@tanstack/react-query"
import { sdk } from "../lib/config"
import { DetailWidgetProps, HttpTypes } from "@medusajs/framework/types"

const ProductWidget = ({ 
  data: productData
}: DetailWidgetProps<HttpTypes.AdminProduct>) => {
  const { mutateAsync } = useMutation({
    mutationFn: (payload: HttpTypes.AdminUpdateProduct) => 
      sdk.admin.product.update(productData.id, payload),
    onSuccess: () => alert("updated product")
  })

  const handleUpdate = () => {
    mutateAsync({
      title: "New Product Title"
    })
  }
  
  return (
    <Container className="divide-y p-0">
      <Button onClick={handleUpdate}>Update Title</Button>
    </Container>
  )
}

export const config = defineWidgetConfig({
  zone: "product.details.before",
})

export default ProductWidget
```

  </CodeTab>
</CodeTabs>

Refer to Tanstack Query's documentation to learn more about sending [Queries](https://tanstack.com/query/latest/docs/framework/react/reference/useQuery#usequery) and [Mutations](https://tanstack.com/query/latest/docs/framework/react/reference/useMutation#usemutation).

### Cache in Next.js Projects

Every method of the SDK that sends requests accepts as a last parameter an object of key-value headers to pass in the request.

In Next.js storefronts or projects, pass the `next.tags` header in the last parameter for data caching.

For example:

```ts highlights={[["2", "next"], ["3", "tags", "An array of tags to cache the data under."]]}
sdk.store.product.list({}, {
  next: {
    tags: ["products"]
  }
})
```

The `tags` property accepts an array of tags that the data is cached under.

Then, to purge the cache later, use Next.js's `revalidateTag` utility:

```ts
import { revalidateTag } from "next/cache";

// ...

revalidateTag("products")
```

Learn more in the [Next.js documentation](https://nextjs.org/docs/app/building-your-application/caching#fetch-optionsnexttags-and-revalidatetag).