# @libp2p/multistream-select

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> JavaScript implementation of multistream-select

# About

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multistream-select is protocol multiplexing per connection/stream. [Full spec here](https://github.com/multiformats/multistream-select)

## Select a protocol flow

The caller will send "interactive" messages, expecting for some acknowledgement from the callee, which will "select" the handler for the desired and supported protocol:

```
< /multistream-select/0.3.0  # i speak multistream-select/0.3.0
> /multistream-select/0.3.0  # ok, let's speak multistream-select/0.3.0
> /ipfs-dht/0.2.3            # i want to speak ipfs-dht/0.2.3
< na                         # ipfs-dht/0.2.3 is not available
> /ipfs-dht/0.1.9            # What about ipfs-dht/0.1.9 ?
< /ipfs-dht/0.1.9            # ok let's speak ipfs-dht/0.1.9 -- in a sense acts as an ACK
> <dht-message>
> <dht-message>
> <dht-message>
```

# Install

```console
$ npm i @libp2p/multistream-select
```

## Browser `<script>` tag

Loading this module through a script tag will make its exports available as `Libp2pMultistreamSelect` in the global namespace.

```html
<script src="https://unpkg.com/@libp2p/multistream-select/dist/index.min.js"></script>
```

# API Docs

- <https://libp2p.github.io/js-libp2p/modules/_libp2p_multistream-select.html>

# License

Licensed under either of

- Apache 2.0, ([LICENSE-APACHE](https://github.com/libp2p/js-libp2p/blob/main/packages/multistream-select/LICENSE-APACHE) / <http://www.apache.org/licenses/LICENSE-2.0>)
- MIT ([LICENSE-MIT](https://github.com/libp2p/js-libp2p/blob/main/packages/multistream-select/LICENSE-MIT) / <http://opensource.org/licenses/MIT>)

# Contribution

Unless you explicitly state otherwise, any contribution intentionally submitted for inclusion in the work by you, as defined in the Apache-2.0 license, shall be dual licensed as above, without any additional terms or conditions.