> ## Documentation Index
> Fetch the complete documentation index at: https://docs.tryreason.dev/llms.txt
> Use this file to discover all available pages before exploring further.

# Javascript client library

> reason-decoder handles decoding the streaming return of your RΞASON app

As talked in [streaming entrypoints](/docs/essentials/entrypoints#returning-yielding-objects) RΞASON, by default, applies a custom encoding to your data.

<Note>
  The custom encoding is only applied you `yield` objects in a streaming entrypoint.
</Note>

This means that you need to decode your data in your client. And this is where the `reason-decoder` package comes in!

## `reason-decoder` package

`reason-decoder` is a package for Javascript/Typescript that handles the decoding of your RΞASON's streamed data.

<Tip>
  If you are using React as your client, we recommend checking out our [React library](/docs/general/react-lib).
</Tip>

Here's how to use it:

```ts An example of using reason-decoder theme={null}
import Decoder from 'reason-decoder'
// 👆 Importing the Decoder

const decoder = new Decoder()
// 👆 Set up the decoder

for await (const streamedData of makeReasonStreamRequest()) {
  /* 👆 Somehow make a HTTP request to RΞASON and
    get its raw streaming response */

  const yourDecodedObject = decoder.decode(streamedData)
  // 👆 Decode the data!
}

```

Note that this does not handle making the HTTP request. `reason-decoder` only handles the decoding of the data.

## A complete example

Here's an example of how you could make a HTTP request to RΞASON and decode it:

```ts An end-to-end example theme={null}
import Decoder from 'reason-decoder'

async function* getReasonData() {
  const decoder = new Decoder()

  const res = await fetch('http://localhost:1704/your-entrypoint', {
    method: 'GET'
  })

  if (!res.ok) throw new Error('Request failed')

  const stream = res.body
  if (!stream) throw new Error('No stream')

  const reader = stream.getReader()
  let result = await reader.read()
  while (!result.done) {
    const { value } = result

    const text = new TextDecoder('utf-8').decode(value)
    yield decoder.decode(text)

    result = await reader.read()
  }
}

async function main() {
  for await (const data of getReasonData()) {
    console.log(data)
  }
}

main()
```