218 lines
14 KiB
HTML
218 lines
14 KiB
HTML
<!doctype html>
|
||
<!--[if lt IE 7]> <html class="no-js lt-ie9 lt-ie8 lt-ie7"> <![endif]-->
|
||
<!--[if IE 7]> <html class="no-js lt-ie9 lt-ie8"> <![endif]-->
|
||
<!--[if IE 8]> <html class="no-js lt-ie9"> <![endif]-->
|
||
<!--[if gt IE 8]><!--> <html> <!--<![endif]-->
|
||
<head>
|
||
<meta charset="utf-8">
|
||
<meta http-equiv="X-UA-Compatible" content="IE=edge,chrome=1">
|
||
<title>Basic State Setting Example - Home Assistant</title>
|
||
<meta name="author" content="Home Assistant">
|
||
<meta name="description" content="">
|
||
<meta name="viewport" content="width=device-width">
|
||
<link rel="canonical" href="https://home-assistant.io/cookbook/python_component_basic_state/">
|
||
<meta property="fb:app_id" content="338291289691179">
|
||
<meta property="og:title" content="Basic State Setting Example">
|
||
<meta property="og:site_name" content="Home Assistant">
|
||
<meta property="og:url" content="https://home-assistant.io/cookbook/python_component_basic_state/">
|
||
<meta property="og:type" content="article">
|
||
<meta property="og:description" content="">
|
||
<meta property="og:image" content="https://home-assistant.io/images/default-social.png">
|
||
<meta name="twitter:card" content="summary_large_image">
|
||
<meta name="twitter:site" content="@home_assistant">
|
||
<meta name="twitter:title" content="Basic State Setting Example">
|
||
<meta name="twitter:description" content="">
|
||
<meta name="twitter:image" content="https://home-assistant.io/images/default-social.png">
|
||
<link href="/stylesheets/screen.css" media="screen, projection" rel="stylesheet">
|
||
<link href="/atom.xml" rel="alternate" title="Home Assistant" type="application/atom+xml">
|
||
<link rel='shortcut icon' href='/images/favicon.ico' />
|
||
<link rel='icon' type='image/png' href='/images/favicon-192x192.png' sizes='192x192' />
|
||
</head>
|
||
<body >
|
||
<header>
|
||
<div class="grid-wrapper">
|
||
<div class="grid">
|
||
<div class="grid__item three-tenths lap-two-sixths palm-one-whole ha-title">
|
||
<a href="/" class="site-title">
|
||
<img width='40' src='/demo/favicon-192x192.png'>
|
||
<span>Home Assistant</span>
|
||
</a>
|
||
</div>
|
||
<div class="grid__item seven-tenths lap-four-sixths palm-one-whole">
|
||
<nav>
|
||
<input type="checkbox" id="toggle">
|
||
<label for="toggle" class="toggle" data-open="Main Menu" data-close="Close Menu"></label>
|
||
<ul class="menu pull-right">
|
||
<li><a href="/getting-started/">Getting started</a></li>
|
||
<li><a href="/components/">Components</a></li>
|
||
<li><a href="/docs/">Docs</a></li>
|
||
<li><a href="/cookbook/">Examples</a></li>
|
||
<li><a href="/developers/">Developers</a></li>
|
||
<li><a href="/blog/">Blog</a></li>
|
||
<li><a href="/help/">Need help?</a></li>
|
||
</ul>
|
||
</nav>
|
||
</div>
|
||
</div>
|
||
</div>
|
||
</header>
|
||
<div class="grid-wrapper">
|
||
<div class="grid grid-center">
|
||
<div class="grid__item two-thirds lap-one-whole palm-one-whole">
|
||
<article class="page">
|
||
<header>
|
||
<h1 class="title indent">
|
||
Basic State Setting Example
|
||
</h1>
|
||
</header>
|
||
<hr class="divider">
|
||
<p>This is a simple tutorial/example on how to write a component for <a href="https://home-assistant.io/">Home Assistant</a>. We will work on a component called “hello_state” to begin with. The purpose of this component is to display a given text in the frontend.</p>
|
||
<p>The setup of a development environment is described in the <a href="/developers/#starting-development">Developers section</a> of the documentation.</p>
|
||
<h2><a class="title-link" name="component" href="#component"></a> Component</h2>
|
||
<p>To get started, create the file <code class="highlighter-rouge"><config dir>/custom_components/hello_state.py</code> and copy the below example code.</p>
|
||
<div class="language-python highlighter-rouge"><pre class="highlight"><code><span class="s">"""
|
||
Support for showing text in the frontend.
|
||
|
||
For more details about this component, please refer to the documentation at
|
||
https://home-assistant.io/components/hello_state/
|
||
"""</span>
|
||
<span class="kn">import</span> <span class="nn">logging</span>
|
||
|
||
<span class="n">_LOGGER</span> <span class="o">=</span> <span class="n">logging</span><span class="o">.</span><span class="n">getLogger</span><span class="p">(</span><span class="n">__name__</span><span class="p">)</span>
|
||
|
||
<span class="n">DOMAIN</span> <span class="o">=</span> <span class="s">'hello_state'</span>
|
||
<span class="n">DEPENDENCIES</span> <span class="o">=</span> <span class="p">[]</span>
|
||
|
||
<span class="k">def</span> <span class="nf">setup</span><span class="p">(</span><span class="n">hass</span><span class="p">,</span> <span class="n">config</span><span class="o">=</span><span class="bp">None</span><span class="p">):</span>
|
||
<span class="s">"""Setup the Hello State component. """</span>
|
||
<span class="n">_LOGGER</span><span class="o">.</span><span class="n">info</span><span class="p">(</span><span class="s">"The 'hello state' component is ready!"</span><span class="p">)</span>
|
||
|
||
<span class="k">return</span> <span class="bp">True</span>
|
||
</code></pre>
|
||
</div>
|
||
<ol>
|
||
<li>In the file header we decided to add some details: A short description and the link to the documentation.</li>
|
||
<li>We want to do some logging. This means that we import the Python logging module and create an alias.</li>
|
||
<li>The component name is equal to the domain name.</li>
|
||
<li>At the moment this component has no dependencies. For detail check <a href="/developers/creating_components/#dependencies">dependencies</a> section.</li>
|
||
<li>
|
||
<p>The <code class="highlighter-rouge">setup</code> function will take care of the initialization of our component.
|
||
The component will only write a log message. Keep in mind for later that you have several options for the severity:</p>
|
||
<ul>
|
||
<li><code class="highlighter-rouge">_LOGGER.info(msg)</code></li>
|
||
<li><code class="highlighter-rouge">_LOGGER.warning(msg)</code></li>
|
||
<li><code class="highlighter-rouge">_LOGGER.error(msg)</code></li>
|
||
<li><code class="highlighter-rouge">_LOGGER.critical(msg)</code></li>
|
||
<li><code class="highlighter-rouge">_LOGGER.exception(msg)</code></li>
|
||
</ul>
|
||
</li>
|
||
<li>We return <code class="highlighter-rouge">True</code> if everything is ok.</li>
|
||
</ol>
|
||
<p>Add the component to your <code class="highlighter-rouge">configuration.yaml</code> file.</p>
|
||
<div class="language-yaml highlighter-rouge"><pre class="highlight"><code><span class="s">hello_state</span><span class="pi">:</span>
|
||
</code></pre>
|
||
</div>
|
||
<p>After a start or a restart of Home Assistant the component will create an entry in the log.</p>
|
||
<div class="language-bash highlighter-rouge"><pre class="highlight"><code>16-03-12 14:16:42 INFO <span class="o">(</span>MainThread<span class="o">)</span> <span class="o">[</span>custom_components.hello_state] The <span class="s1">'hello state'</span> component is ready!
|
||
</code></pre>
|
||
</div>
|
||
<p>The next step is the introduction of configuration options. Most configuration details are coming out of the <code class="highlighter-rouge">configuration.yaml</code> file. To do that we need to update the <code class="highlighter-rouge">def setup()</code> method to accept configuration information and access the configuration variable in the <code class="highlighter-rouge">setup</code> method.</p>
|
||
<p>More details about this topic can be found in the <a href="/developers/creating_components/#config-user-given-configuration">User given configuration</a> section.</p>
|
||
<div class="language-python highlighter-rouge"><pre class="highlight"><code><span class="kn">import</span> <span class="nn">logging</span>
|
||
|
||
<span class="n">_LOGGER</span> <span class="o">=</span> <span class="n">logging</span><span class="o">.</span><span class="n">getLogger</span><span class="p">(</span><span class="n">__name__</span><span class="p">)</span>
|
||
|
||
<span class="n">DOMAIN</span> <span class="o">=</span> <span class="s">'hello_state'</span>
|
||
<span class="n">DEPENDENCIES</span> <span class="o">=</span> <span class="p">[]</span>
|
||
|
||
<span class="n">CONF_TEXT</span> <span class="o">=</span> <span class="s">'text'</span>
|
||
<span class="n">DEFAULT_TEXT</span> <span class="o">=</span> <span class="s">'No text!'</span>
|
||
|
||
<span class="k">def</span> <span class="nf">setup</span><span class="p">(</span><span class="n">hass</span><span class="p">,</span> <span class="n">config</span><span class="p">):</span>
|
||
<span class="s">"""Setup the Hello State component. """</span>
|
||
<span class="c"># Get the text from the configuration. Use DEFAULT_TEXT if no name is provided.</span>
|
||
<span class="n">text</span> <span class="o">=</span> <span class="n">config</span><span class="p">[</span><span class="n">DOMAIN</span><span class="p">]</span><span class="o">.</span><span class="n">get</span><span class="p">(</span><span class="n">CONF_TEXT</span><span class="p">,</span> <span class="n">DEFAULT_TEXT</span><span class="p">)</span>
|
||
|
||
<span class="c"># States are in the format DOMAIN.OBJECT_ID</span>
|
||
<span class="n">hass</span><span class="o">.</span><span class="n">states</span><span class="o">.</span><span class="nb">set</span><span class="p">(</span><span class="s">'hello_state.Hello_State'</span><span class="p">,</span> <span class="n">text</span><span class="p">)</span>
|
||
|
||
<span class="k">return</span> <span class="bp">True</span>
|
||
</code></pre>
|
||
</div>
|
||
<p>To add the latest feature of our component, update the entry in your <code class="highlighter-rouge">configuration.yaml</code> file.</p>
|
||
<div class="language-yaml highlighter-rouge"><pre class="highlight"><code><span class="s">hello_state</span><span class="pi">:</span>
|
||
<span class="s">text</span><span class="pi">:</span> <span class="s1">'</span><span class="s">Hello,</span><span class="nv"> </span><span class="s">World!'</span>
|
||
</code></pre>
|
||
</div>
|
||
<p>Thanks to <code class="highlighter-rouge">DEFAULT_TEXT</code> variable the component will launch even if no <code class="highlighter-rouge">text:</code> field is used in the <code class="highlighter-rouge">configuration.yaml</code> file. Quite often there are variables which are required. It’s important to check if all mandatory configuration variables are provided. If not, the setup should fail. We will use <code class="highlighter-rouge">voluptuous</code> as a helper to achive this. The next listing shows the essential parts.</p>
|
||
<div class="language-python highlighter-rouge"><pre class="highlight"><code><span class="kn">import</span> <span class="nn">voluptuous</span> <span class="kn">as</span> <span class="nn">vol</span>
|
||
|
||
<span class="kn">import</span> <span class="nn">homeassistant.helpers.config_validation</span> <span class="kn">as</span> <span class="nn">cv</span>
|
||
<span class="p">[</span><span class="o">...</span><span class="p">]</span>
|
||
<span class="n">PLATFORM_SCHEMA</span> <span class="o">=</span> <span class="n">PLATFORM_SCHEMA</span><span class="o">.</span><span class="n">extend</span><span class="p">({</span>
|
||
<span class="n">vol</span><span class="o">.</span><span class="n">Required</span><span class="p">(</span><span class="n">CONF_TEXT</span><span class="p">):</span> <span class="n">cv</span><span class="o">.</span><span class="n">string</span><span class="p">,</span>
|
||
<span class="p">})</span>
|
||
</code></pre>
|
||
</div>
|
||
<p>If <code class="highlighter-rouge">text:</code> is missing, there will be a warning in the log file.</p>
|
||
<p>After a start or a restart of Home Assistant the component will be visible in the frontend if the <code class="highlighter-rouge">configuration.yaml</code> file is up-to-date.</p>
|
||
<p class="img">
|
||
<img src="/images/screenshots/create-component01.png" />
|
||
</p>
|
||
<p>To get your component included in the Home Assistant releases, follow the steps described in the <a href="https://home-assistant.io/developers/#submitting-improvements">Submitting improvements</a> section. Basically you only need to move your component in the <code class="highlighter-rouge">homeassistant/component/</code> directory of your fork and create a Pull Request.</p>
|
||
</article>
|
||
</div>
|
||
<aside id="sidebar" class="grid__item one-third lap-one-whole palm-one-whole">
|
||
<div class="grid">
|
||
<section class="aside-module grid__item one-whole lap-one-half">
|
||
<div class='edit-github'><a href='https://github.com/home-assistant/home-assistant.github.io/tree/current/source/_cookbook/python_component_basic_state.markdown'>Edit this page on GitHub</a></div>
|
||
<div class='section'>
|
||
<a href='/cookbook'>Back to the cookbook</a>
|
||
</div>
|
||
<div class='section'>
|
||
<h1 class="title delta">Custom Python Component Examples</h1>
|
||
<ul class='divided'>
|
||
<li>
|
||
<a href='/cookbook/python_component_mqtt_basic/'>Basic MQTT Example</a>
|
||
</li>
|
||
<li>
|
||
<a href='/cookbook/python_component_basic_service/'>Basic Service Example</a>
|
||
</li>
|
||
<li>
|
||
Basic State Setting Example
|
||
</li>
|
||
</ul>
|
||
</div>
|
||
</section>
|
||
</div>
|
||
</aside>
|
||
</div>
|
||
</div>
|
||
<footer>
|
||
<div class="grid-wrapper">
|
||
<div class="grid">
|
||
<div class="grid__item">
|
||
<div class="copyright">
|
||
<a rel="me" href='https://twitter.com/home_assistant'><i class="icon-twitter"></i></a>
|
||
<a rel="me" href='https://facebook.com/homeassistantio'><i class="icon-facebook"></i></a>
|
||
<a rel="me" href='https://plus.google.com/110560654828510104551'><i class="icon-google-plus"></i></a>
|
||
<a rel="me" href='https://github.com/home-assistant/home-assistant'><i class="icon-github"></i></a>
|
||
<div class="credit">
|
||
Contact us at <a href='mailto:hello@home-assistant.io'>hello@home-assistant.io</a>.<br>
|
||
Website powered by <a href='http://jekyllrb.com/'>Jekyll</a> and the <a href='https://github.com/coogie/oscailte'>Oscalite theme</a>.<br />
|
||
Hosted by <a href='https://pages.github.com/'>GitHub</a> and served by <a href='https://cloudflare.com'>CloudFlare</a>.
|
||
</div>
|
||
<a rel="license" href="http://creativecommons.org/licenses/by-nc-sa/4.0/"><img alt="Creative Commons License" style="border-width:0" src="https://i.creativecommons.org/l/by-nc-sa/4.0/88x31.png" /></a><br /><span xmlns:dct="http://purl.org/dc/terms/" property="dct:title">home-assistant.io</span> is licensed under a <a rel="license" href="http://creativecommons.org/licenses/by-nc-sa/4.0/">Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License</a>.
|
||
</div>
|
||
</div>
|
||
</div>
|
||
</div>
|
||
</footer>
|
||
<script>
|
||
var _gaq=[['_setAccount','UA-57927901-1'],['_trackPageview']];
|
||
(function(d,t){var g=d.createElement(t),s=d.getElementsByTagName(t)[0];
|
||
g.src=('https:'==location.protocol?'//ssl':'//www')+'.google-analytics.com/ga.js';
|
||
s.parentNode.insertBefore(g,s)}(document,'script'));
|
||
</script>
|
||
</body>
|
||
</html>
|