<!DOCTYPE html><html><head><title>Channel</title><meta charset="utf-8"/><meta content="IE=edge,chrome=1" http-equiv="X-UA-Compatible"/><meta name="viewport" content="width=device-width, initial-scale=1.0"/><meta class="swiftype" name="title" data-type="string" content="Channel"/><link rel="canonical" href="https://docs.prediction.io/datacollection/channel/"/><link href="/images/favicon/normal-b330020a.png" rel="shortcut icon"/><link href="/images/favicon/apple-c0febcf2.png" rel="apple-touch-icon"/><link href="//fonts.googleapis.com/css?family=Open+Sans:300italic,400italic,600italic,700italic,800italic,400,300,600,700,800" rel="stylesheet"/><link href="//maxcdn.bootstrapcdn.com/font-awesome/4.2.0/css/font-awesome.min.css" rel="stylesheet"/><link href="/stylesheets/application-3598c7d7.css" rel="stylesheet" type="text/css"/><!--[if lt IE 9]><script src="//cdnjs.cloudflare.com/ajax/libs/html5shiv/3.7.2/html5shiv.min.js"></script><![endif]--><script src="//cdn.mathjax.org/mathjax/latest/MathJax.js?config=TeX-AMS-MML_HTMLorMML"></script><script>(function(i,s,o,g,r,a,m){i['GoogleAnalyticsObject']=r;i[r]=i[r]||function(){
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class="container-fluid"><div class="row"><div id="left-menu-wrapper" class="col-md-3"><nav id="nav-main"><ul><li class="level-1"><a class="expandible" href="/"><span>Apache PredictionIO (incubating) Documentation</span></a><ul><li class="level-2"><a class="final" href="/"><span>Welcome to Apache PredictionIO (incubating)</span></a></li></ul></li><li class="level-1"><a class="expandible" href="#"><span>Getting Started</span></a><ul><li class="level-2"><a class="final" href="/start/"><span>A Quick Intro</span></a></li><li class="level-2"><a class="final" href="/install/"><span>Installing Apache PredictionIO (incubating)</span></a></li><li class="level-2"><a class="final" href="/start/download/"><span>Downloading an Engine Template</span></a></li><li class="level-2"><a class="final" href="/start/deploy/"><span>Deploying Your First Engine</span></a></li><li class="level-2"><a class="final" href="/start/customize/"><span>Customizing the Engine</span></a></li></ul></li><li class="level-1"><a 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Help</span></a><ul><li class="level-2"><a class="final" href="/resources/faq/"><span>FAQs</span></a></li><li class="level-2"><a class="final" href="/support/"><span>Community Support</span></a></li><li class="level-2"><a class="final" href="/support/#enterprise-support"><span>Enterprise Support</span></a></li></ul></li><li class="level-1"><a class="expandible" href="#"><span>Resources</span></a><ul><li class="level-2"><a class="final" href="/resources/intellij/"><span>Developing Engines with IntelliJ IDEA</span></a></li><li class="level-2"><a class="final" href="/resources/upgrade/"><span>Upgrade Instructions</span></a></li><li class="level-2"><a class="final" href="/resources/glossary/"><span>Glossary</span></a></li></ul></li></ul></nav></div><div class="col-md-9 col-sm-12"><div class="content-header hidden-md hidden-lg"><div id="breadcrumbs" class="hidden-sm hidden xs"><ul><li><a href="#">Collecting and Analyzing Data</a><span class="spacer">&gt;</span></li><li><span class="last">Channel</span></li></ul></div><div id="page-title"><h1>Channel</h1></div></div><div id="table-of-content-wrapper"><h5>On this page</h5><aside id="table-of-contents"><ul> <li> <a href="#create-a-new-channel">Create a new Channel</a> </li> <li> <a href="#collect-data-through-channel">Collect data through Channel</a> </li> <li> <a href="#delete-a-channel-including-all-imported-data">Delete a Channel (including all imported data)</a> </li> <li> <a href="#delete-the-data-only-of-a-channel">Delete the data-only of a Channel</a> </li> <li> <a href="#accessing-channel-data-in-engine">Accessing Channel Data in Engine</a> </li> </ul> </aside><hr/><a id="edit-page-link" href="https://github.com/apache/incubator-predictionio/tree/livedoc/docs/manual/source/datacollection/channel.html.md.erb"><img src="/images/icons/edit-pencil-d6c1bb3d.png"/>Edit this page</a></div><div class="content-header hidden-sm hidden-xs"><div id="breadcrumbs" class="hidden-sm hidden xs"><ul><li><a href="#">Collecting and Analyzing Data</a><span class="spacer">&gt;</span></li><li><span class="last">Channel</span></li></ul></div><div id="page-title"><h1>Channel</h1></div></div><div class="content"><p>Each App has a default channel (without name) which stores all incoming events. This &quot;default&quot; one is used when channel is not specified.</p><p>You may create additional Channels for the App. Creating multiple Channels is advanced usage. You don&#39;t need to create any in order to use Apache PredictionIO (incubating). The Channel is associated with one App only and must have unique name within the same App.</p><p>Creating multiple Channels allows you more easily to identify, manage and use specific event data if you may collect events from different multiple sources (eg. mobile, website, or third-party webhooks service) for the your application.</p><p>(More usage details coming soon...)</p><h2 id='create-a-new-channel' class='header-anchors'>Create a new Channel</h2><p>For example, to create a new channel &quot;myChannel&quot; for app &quot;myApp&quot;, run following <code>pio</code> command:</p><div class="highlight shell"><table style="border-spacing: 0"><tbody><tr><td class="gutter gl" style="text-align: right"><pre class="lineno">1</pre></td><td class="code"><pre>pio app channel-new myApp myChannel
</pre></td></tr></tbody></table> </div> <p>you should see something like the following outputs:</p><div class="highlight shell"><table style="border-spacing: 0"><tbody><tr><td class="gutter gl" style="text-align: right"><pre class="lineno">1
2
3
4
5
6
7</pre></td><td class="code"><pre><span class="o">[</span>INFO] <span class="o">[</span>App<span class="nv">$]</span> Updated Channel meta-data.
<span class="o">[</span>INFO] <span class="o">[</span>HBLEvents] The table predictionio_eventdata:events_5_2 doesn<span class="s1">'t exist yet. Creating now...
[INFO] [App$] Initialized Event Store for the channel: myChannel.
[INFO] [App$] Created new channel:
[INFO] [App$]     Channel Name: myChannel
[INFO] [App$]       Channel ID: 2
[INFO] [App$]           App ID: 5
</span></pre></td></tr></tbody></table> </div> <p>Now &quot;myChannel&quot; is created and ready for collecting data.</p><h2 id='collect-data-through-channel' class='header-anchors'>Collect data through Channel</h2><p>The Event API support optional <code>channel</code> query parameter. This allows you to import and query events of the specified channel. When the <code>channel</code> parameter is not specified, the data is collected through the default channel.</p><p>URL: <code>http://localhost:7070/events.json?accessKey=yourAccessKeyString&amp;channel=yourChannelName</code></p><p>Query parameters:</p> <table><thead> <tr> <th style="text-align: left">Field</th> <th style="text-align: left">Type</th> <th style="text-align: left">Description</th> </tr> </thead><tbody> <tr> <td style="text-align: left"><code>accessKey</code></td> <td style="text-align: left">String</td> <td style="text-align: left">The Access Key for your App</td> </tr> <tr> <td style="text-align: left"><code>channel</code></td> <td style="text-align: left">String</td> <td style="text-align: left">The channel name (optional). Specify this to import data to this channel. <strong>NOTE: supported in PIO version &gt;= 0.9.2</strong> only. Channel must be created first.</td> </tr> </tbody></table> <p>For SDK usage, one EventClient should be responsible for collecting data of one specific channel. The channel name is specified when the EventClient object is instantiated.</p><p>For example, the following code import event to &quot;YOUR_CHANNEL&quot; of the corresponding App.</p><div class="tabs"> <ul class="control"> <li data-lang="bash"><a href="#tab-aa76995b-2398-4afb-8a41-ab4568048344">Raw HTTP</a></li> <li data-lang="php"><a href="#tab-d421833b-782e-47b0-9ed4-5992ce24cff3">PHP SDK</a></li> <li data-lang="python"><a href="#tab-7844e8e4-f556-4837-9eb1-679fbdaaeebe">Python SDK</a></li> <li data-lang="ruby"><a href="#tab-229c2ff4-d861-4b36-8ad3-de4ce32d87a6">Ruby SDK</a></li> <li data-lang="java"><a href="#tab-03fb8998-6e2b-489d-a090-c5aeebb79407">Java SDK</a></li> </ul> <div data-tab="Raw HTTP" data-lang="bash" id="tab-aa76995b-2398-4afb-8a41-ab4568048344"> <div class="highlight shell"> <table style="border-spacing: 0"><tbody><tr> <td class="gutter gl" style="text-align: right"><pre class="lineno">1
2
3
4
5
6
7
8
9
10
11
12
13
14</pre></td> <td class="code"><pre><span class="gp">$ </span>curl -i -X POST http://localhost:7070/events.json?accessKey<span class="o">=</span>YOUR_ACCESS_KEY&amp;channel<span class="o">=</span>YOUR_CHANNEL <span class="se">\</span>
-H <span class="s2">"Content-Type: application/json"</span> <span class="se">\</span>
-d <span class="s1">'{
  "event" : "my_event",
  "entityType" : "user",
  "entityId" : "uid",
  "targetEntityType" : "item",
  "targetEntityId" : "iid",
  "properties" : {
    "someProperty" : "value1",
    "anotherProperty" : "value2"
  },
  "eventTime" : "2004-12-13T21:39:45.618Z"
}'</span>
</pre></td> </tr></tbody></table> </div> </div> <div data-tab="PHP SDK" data-lang="php" id="tab-d421833b-782e-47b0-9ed4-5992ce24cff3"> (TODO: update me) </div> <div data-tab="Python SDK" data-lang="python" id="tab-7844e8e4-f556-4837-9eb1-679fbdaaeebe"> <div class="highlight python"> <table style="border-spacing: 0"><tbody><tr> <td class="gutter gl" style="text-align: right"><pre class="lineno">1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21</pre></td> <td class="code"><pre><span class="kn">from</span> <span class="nn">predictionio</span> <span class="kn">import</span> <span class="n">EventClient</span>
<span class="kn">from</span> <span class="nn">datetime</span> <span class="kn">import</span> <span class="n">datetime</span>
<span class="kn">import</span> <span class="nn">pytz</span>

<span class="c"># Create a EventClient for "YOUR_CHANNEL"</span>
<span class="n">client</span> <span class="o">=</span> <span class="n">EventClient</span><span class="p">(</span><span class="s">'YOUR_ACCESS_KEY'</span><span class="p">,</span> <span class="s">"http://localhost:7070"</span><span class="p">,</span>
  <span class="n">channel</span><span class="o">=</span><span class="s">'YOUR_CHANNEL'</span><span class="p">)</span> <span class="c"># default channel if not specified</span>

<span class="n">event_properties</span> <span class="o">=</span> <span class="p">{</span>
    <span class="s">"someProperty"</span> <span class="p">:</span> <span class="s">"value1"</span><span class="p">,</span>
    <span class="s">"anotherProperty"</span> <span class="p">:</span> <span class="s">"value2"</span><span class="p">,</span>
    <span class="p">}</span>
<span class="n">event_response</span> <span class="o">=</span> <span class="n">client</span><span class="o">.</span><span class="n">create_event</span><span class="p">(</span>
    <span class="n">event</span><span class="o">=</span><span class="s">"my_event"</span><span class="p">,</span>
    <span class="n">entity_type</span><span class="o">=</span><span class="s">"user"</span><span class="p">,</span>
    <span class="n">entity_id</span><span class="o">=</span><span class="s">"uid"</span><span class="p">,</span>
    <span class="n">target_entity_type</span><span class="o">=</span><span class="s">"item"</span><span class="p">,</span>
    <span class="n">target_entity_id</span><span class="o">=</span><span class="s">"iid"</span><span class="p">,</span>
    <span class="n">properties</span><span class="o">=</span><span class="n">event_properties</span><span class="p">,</span>
    <span class="n">event_time</span><span class="o">=</span><span class="n">datetime</span><span class="p">(</span><span class="mi">2014</span><span class="p">,</span> <span class="mi">12</span><span class="p">,</span> <span class="mi">13</span><span class="p">,</span> <span class="mi">21</span><span class="p">,</span> <span class="mi">38</span><span class="p">,</span> <span class="mi">45</span><span class="p">,</span> <span class="mi">618000</span><span class="p">,</span> <span class="n">pytz</span><span class="o">.</span><span class="n">utc</span><span class="p">))</span>

</pre></td> </tr></tbody></table> </div> </div> <div data-tab="Ruby SDK" data-lang="ruby" id="tab-229c2ff4-d861-4b36-8ad3-de4ce32d87a6"> (TODO: update me) </div> <div data-tab="Java SDK" data-lang="java" id="tab-03fb8998-6e2b-489d-a090-c5aeebb79407"> <div class="highlight java"> <table style="border-spacing: 0"><tbody><tr> <td class="gutter gl" style="text-align: right"><pre class="lineno">1</pre></td> <td class="code"><pre><span class="o">(</span><span class="n">coming</span> <span class="n">soon</span><span class="o">)</span>
</pre></td> </tr></tbody></table> </div> </div> </div> <p>You can also follow the EventAPI <a href="/datacollection/eventapi/#debugging-recipes">debug receipts</a> to query the events of specific channel by adding the <code>channel</code> query parameter in the URL.</p><h2 id='delete-a-channel-(including-all-imported-data)' class='header-anchors'>Delete a Channel (including all imported data)</h2><div class="highlight shell"><table style="border-spacing: 0"><tbody><tr><td class="gutter gl" style="text-align: right"><pre class="lineno">1</pre></td><td class="code"><pre>pio app channel-delete &lt;app name&gt; &lt;channel name&gt;
</pre></td></tr></tbody></table> </div> <h2 id='delete-the-data-only-of-a-channel' class='header-anchors'>Delete the data-only of a Channel</h2><div class="highlight shell"><table style="border-spacing: 0"><tbody><tr><td class="gutter gl" style="text-align: right"><pre class="lineno">1</pre></td><td class="code"><pre>pio app data-delete &lt;app name&gt; --channel &lt;channel name&gt;
</pre></td></tr></tbody></table> </div> <h2 id='accessing-channel-data-in-engine' class='header-anchors'>Accessing Channel Data in Engine</h2><p>To acccess channel data, simply specify the channel name when use the PEventStore or LEventStore API. Data is read from from the default channel if channelName is not specified.</p><p>For example, read data from default channel:</p><div class="highlight scala"><table style="border-spacing: 0"><tbody><tr><td class="gutter gl" style="text-align: right"><pre class="lineno">1
2
3
4
5
6
7
8</pre></td><td class="code"><pre>
    <span class="k">val</span> <span class="n">eventsRDD</span><span class="k">:</span> <span class="kt">RDD</span><span class="o">[</span><span class="kt">Event</span><span class="o">]</span> <span class="k">=</span> <span class="nc">PEventStore</span><span class="o">.</span><span class="n">find</span><span class="o">(</span>
      <span class="n">appName</span> <span class="k">=</span> <span class="n">dsp</span><span class="o">.</span><span class="n">appName</span><span class="o">,</span>
      <span class="n">entityType</span> <span class="k">=</span> <span class="nc">Some</span><span class="o">(</span><span class="s">"user"</span><span class="o">),</span>
      <span class="n">eventNames</span> <span class="k">=</span> <span class="nc">Some</span><span class="o">(</span><span class="nc">List</span><span class="o">(</span><span class="s">"rate"</span><span class="o">,</span> <span class="s">"buy"</span><span class="o">)),</span> <span class="c1">// read "rate" and "buy" event
</span>      <span class="c1">// targetEntityType is optional field of an event.
</span>      <span class="n">targetEntityType</span> <span class="k">=</span> <span class="nc">Some</span><span class="o">(</span><span class="nc">Some</span><span class="o">(</span><span class="s">"item"</span><span class="o">)))(</span><span class="n">sc</span><span class="o">)</span>

</pre></td></tr></tbody></table> </div> <p>For examlpe, read data from the channel &quot;CHANNEL_NAME&quot;</p><div class="highlight scala"><table style="border-spacing: 0"><tbody><tr><td class="gutter gl" style="text-align: right"><pre class="lineno">1
2
3
4
5
6
7
8
9</pre></td><td class="code"><pre>
    <span class="k">val</span> <span class="n">eventsRDD</span><span class="k">:</span> <span class="kt">RDD</span><span class="o">[</span><span class="kt">Event</span><span class="o">]</span> <span class="k">=</span> <span class="nc">PEventStore</span><span class="o">.</span><span class="n">find</span><span class="o">(</span>
      <span class="n">appName</span> <span class="k">=</span> <span class="n">dsp</span><span class="o">.</span><span class="n">appName</span><span class="o">,</span>
      <span class="n">channelName</span> <span class="k">=</span> <span class="nc">Some</span><span class="o">(</span><span class="s">"CHANNEL_NAME"</span><span class="o">),</span> <span class="c1">// ADDED
</span>      <span class="n">entityType</span> <span class="k">=</span> <span class="nc">Some</span><span class="o">(</span><span class="s">"user"</span><span class="o">),</span>
      <span class="n">eventNames</span> <span class="k">=</span> <span class="nc">Some</span><span class="o">(</span><span class="nc">List</span><span class="o">(</span><span class="s">"rate"</span><span class="o">,</span> <span class="s">"buy"</span><span class="o">)),</span> <span class="c1">// read "rate" and "buy" event
</span>      <span class="c1">// targetEntityType is optional field of an event.
</span>      <span class="n">targetEntityType</span> <span class="k">=</span> <span class="nc">Some</span><span class="o">(</span><span class="nc">Some</span><span class="o">(</span><span class="s">"item"</span><span class="o">)))(</span><span class="n">sc</span><span class="o">)</span>

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