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---
title: "Server-sent events"
---
The [server-sent events](https://developer.mozilla.org/en-US/docs/Web/API/Server-sent_events/Using_server-sent_events) feature is a one-way channel from your Home Assistant server to a client which is acting as a consumer. For a bi-directional streaming API, check out the [WebSocket API](external_api_websocket.md).
The URI that is generating the data is `/api/stream`.
A requirement on the client-side is existing support for the [EventSource](https://developer.mozilla.org/en-US/docs/Web/API/EventSource) interface.
There are various ways to access the stream. If you have not set an `api_password` in the [`http`](https://www.home-assistant.io/components/http/) section of your `configuration.yaml` file then you use your modern browser to read the messages. A command-line option is `curl`:
```shell
$ curl -X GET -H 'Authorization: Bearer ABCDEFGH' \
-H "Content-Type: application/json" http://localhost:8123/api/stream
```
:::caution
Will no longer work with the new Authentication system.
:::
You can create a convenient view for this by creating an HTML file (`sse.html`) in the `www` folder of your Home Assistant configuration directory (`.homeassistant`). Paste this snippet into the file:
```html
<!DOCTYPE html>
<html>
<body>
<h1>Getting Home Assistant server events</h1>
<div id="events"></div>
<script type="text/javascript">
var source = new EventSource("/api/stream?api_password=YOUR_PASSWORD");
source.onmessage = function(event) {
document.getElementById("events").innerHTML += event.data + "<br>";
};
</script>
</body>
</html>
```
Visit [http://localhost:8123/local/sse.html](http://localhost:8123/local/sse.html) to see the stream of events.
## Examples
A simple way to consume server-sent events is to use a command-line http client like [httpie](https://httpie.org/). Installation info is on the site (if you use Homebrew, it's `brew install httpie`). Once installed, run this snippet from your terminal:
```shell
$ http --stream http://localhost:8123/api/stream 'Authorization:Bearer ABCDEFGH' content-type:application/json
```
### Website
:::caution
Will no longer work with the new Authentication system.
:::
The [home-assistant-sse](https://github.com/fabaff/home-assistant-sse) repository contains a more advanced example.
### Python
If you want to test the server-sent events without creating a website, the Python module [`sseclient` ](https://pypi.python.org/pypi/sseclient/) can help. To install (assuming Python and pip3 are already installed):
```shell
$ pip3 install sseclient
```
A simple script to consume SSE in Python looks like this:
```python
from sseclient import SSEClient
auth = {"Authorization": "Bearer ABCDEFGH"}
messages = SSEClient("http://localhost:8123/api/stream", headers=auth)
for msg in messages:
print(msg)
```