doc/afm-system-daemon.html

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  18 <h1 class="title">The afm-system-daemon</h1>
  19 <h2 class="author">José Bollo</h2>
  20 <h2 class="author">Fulup Ar Foll</h2>
  21 <h3 class="date">24 juin 2016</h3>
  22 </header>
  23 <nav id="TOC">
  24 <ul>
  25 <li><a href="#the-afm-system-daemon">The afm-system-daemon</a><ul>
  26 <li><a href="#foreword">Foreword</a></li>
  27 <li><a href="#introduction">Introduction</a></li>
  28 <li><a href="#starting-afm-system-daemon">Starting <strong>afm-system-daemon</strong></a></li>
  29 <li><a href="#the-d-bus-interface">The D-Bus interface</a><ul>
  30 <li><a href="#overview-of-the-dbus-interface">Overview of the dbus interface</a></li>
  31 <li><a href="#the-protocol-over-d-bus">The protocol over D-Bus</a></li>
  32 </ul></li>
  33 </ul></li>
  34 </ul>
  35 </nav>
  36 <h1 id="the-afm-system-daemon">The afm-system-daemon</h1>
  37 <h2 id="foreword">Foreword</h2>
  38 <p>This document describes application framework system daemon fundamentals. FCF (Fully Conform to Specification) implementation is still under development. It may happen that current implementation somehow diverges with specifications.</p>
  39 <h2 id="introduction">Introduction</h2>
  40 <p>The daemon <strong>afm-system-daemon</strong> is in charge of installing applications on AGL system. Its main tasks are:</p>
  41 <ul>
  42 <li><p>installs applications and setup security framework for newly installed application.</p></li>
  43 <li><p>uninstall applications</p></li>
  44 </ul>
  45 <p>The <strong>afm-system-daemon</strong> takes its orders from system instance of D-Bus.</p>
  46 <p>The figure below summarizes the situation of <strong>afm-system-daemon</strong> in the system.</p>
  47 <pre><code>+------------------------------------------------------------+
  48 |                          User                              |
  49 |                                                            |
  50 |     +-------------------------------------------------+    |
  51 |     |                                                 |    |
  52 |     |                  afm-user-daemon                |    |
  53 |     |                                                 |    |
  54 |     +----------+----------------------+----------+----+    |
  55 |                |                      |          :         |
  56 |                |                      |          :         |
  57 :================|======================|==========:=========:
  58 |                |                      |          :         |
  59 |     +----------+----------+     +-----+-----+    :         |
  60 |     |   D-Bus   system    +-----+  CYNARA   |    :         |
  61 |     +----------+----------+     +-----+-----+    :         |
  62 |                |                      |          :         |
  63 |     +----------+---------+    +-------+----------+----+    |
  64 |     | afm-system-daemon  +----+   SECURITY-MANAGER    |    |
  65 |     +--------------------+    +-----------------------+    |
  66 |                                                            |
  67 |                          System                            |
  68 +------------------------------------------------------------+</code></pre>
  69 <h2 id="starting-afm-system-daemon">Starting <strong>afm-system-daemon</strong></h2>
  70 <p><strong>afm-system-daemon</strong> is launched as a <strong>systemd</strong> service attached to system. Normally, the service file is located at /lib/systemd/system/afm-system-daemon.service.</p>
  71 <p>The options for launching <strong>afm-system-daemon</strong> are:</p>
  72 <pre><code>-r
  73 --root directory
  74
  75      Set the root application directory.
  76
  77      Note that the default root directory is defined
  78      to be /usr/share/afm/applications (may change).
  79
  80 -d
  81 --daemon
  82
  83      Daemonizes the process. It is not needed by sytemd.
  84
  85 -q
  86 --quiet
  87
  88      Reduces the verbosity (can be repeated).
  89
  90 -v
  91 --verbose
  92
  93      Increases the verbosity (can be repeated).
  94
  95 -h
  96 --help
  97
  98      Prints a short help.</code></pre>
  99 <h2 id="the-d-bus-interface">The D-Bus interface</h2>
 100 <h3 id="overview-of-the-dbus-interface">Overview of the dbus interface</h3>
 101 <p><strong><em>afm-system-daemon</em></strong> takes its orders from the session instance of D-Bus. The use of D-Bus is great because it allows to implement discovery and signaling.</p>
 102 <p>The <strong>afm-system-daemon</strong> is listening with the destination name <strong><em>org.AGL.afm.system</em></strong> at the object of path <strong><em>/org/AGL/afm/system</em></strong> on the interface <strong><em>org.AGL.afm.system</em></strong> for the below detailed members <strong><em>install</em></strong> and <strong><em>uninstall</em></strong>.</p>
 103 <p>D-Bus is mainly used for signaling and discovery. Its optimized typed protocol is not used except for transmitting only one string in both directions.</p>
 104 <p>The client and the service are using JSON serialization to exchange data.</p>
 105 <p>The D-Bus interface is defined by:</p>
 106 <ul>
 107 <li><p>DESTINATION: <strong>org.AGL.afm.system</strong></p></li>
 108 <li><p>PATH: <strong>/org/AGL/afm/system</strong></p></li>
 109 <li><p>INTERFACE: <strong>org.AGL.afm.system</strong></p></li>
 110 </ul>
 111 <p>The signature of any member of the interface is <strong><em>string -&gt; string</em></strong> for <strong><em>JSON -&gt; JSON</em></strong>.</p>
 112 <p>This is the normal case. In case of error, the current implementation returns a dbus error that is a string.</p>
 113 <p>Here is an example using <em>dbus-send</em> to query data on installed applications.</p>
 114 <pre><code>dbus-send --session --print-reply \
 115     --dest=org.AGL.afm.system \
 116     /org/AGL/afm/system \
 117     org.AGL.afm.system.install &#39;string:&quot;/tmp/appli.wgt&quot;&#39;</code></pre>
 118 <h3 id="the-protocol-over-d-bus">The protocol over D-Bus</h3>
 119 <hr />
 120 <h4 id="method-org.agl.afm.system.install">Method org.AGL.afm.system.install</h4>
 121 <p><strong>Description</strong>: Install an application from a widget file.</p>
 122 <p>When an application with the same <em>id</em> and <em>version</em> already exists. Outside of using <em>force=true</em> the application is not reinstalled.</p>
 123 <p>Applications are installed the subdirectories of applications common directory. If <em>root</em> is specified, the application is installed under the sub-directories of the <em>root</em> defined.</p>
 124 <p>Note that this methods is a simple accessor method of <strong><em>org.AGL.afm.system.install</em></strong> from <strong><em>afm-system-daemon</em></strong>.</p>
 125 <p>After the installation and before returning to the sender, <strong><em>afm-system-daemon</em></strong> sends a signal <strong><em>org.AGL.afm.system.changed</em></strong>.</p>
 126 <p><strong>Input</strong>: The <em>path</em> of the widget file to install and, optionally, a flag to <em>force</em> reinstallation, and, optionally, a <em>root</em> directory.</p>
 127 <p>Either just a string being the absolute path of the widget file:</p>
 128 <pre><code>&quot;/a/path/driving/to/the/widget&quot;</code></pre>
 129 <p>Or an object:</p>
 130 <pre><code>{
 131   &quot;wgt&quot;: &quot;/a/path/to/the/widget&quot;,
 132   &quot;force&quot;: false,
 133   &quot;root&quot;: &quot;/a/path/to/the/root&quot;
 134 }</code></pre>
 135 <p>&quot;wgt&quot; and &quot;root&quot; must be absolute paths.</p>
 136 <p><strong>output</strong>: An object with the field &quot;added&quot; being the string for the id of the added application.</p>
 137 <pre><code>{&quot;added&quot;:&quot;appli@x.y&quot;}</code></pre>
 138 <hr />
 139 <h4 id="method-org.agl.afm.system.uninstall">Method org.AGL.afm.system.uninstall</h4>
 140 <p><strong>Description</strong>: Uninstall an application from its id.</p>
 141 <p>Note that this methods is a simple method accessor of <strong><em>org.AGL.afm.system.uninstall</em></strong> from <strong><em>afm-system-daemon</em></strong>.</p>
 142 <p>After the uninstallation and before returning to the sender, <strong><em>afm-system-daemon</em></strong> sends a signal <strong><em>org.AGL.afm.system.changed</em></strong>.</p>
 143 <p><strong>Input</strong>: the <em>id</em> of the application and optionally the application <em>root</em> path.</p>
 144 <p>Either a string:</p>
 145 <pre><code>&quot;appli@x.y&quot;</code></pre>
 146 <p>Or an object:</p>
 147 <pre><code>{
 148   &quot;id&quot;: &quot;appli@x.y&quot;,
 149   &quot;root&quot;: &quot;/a/path/to/the/root&quot;
 150 }</code></pre>
 151 <p><strong>output</strong>: the value 'true'.</p>
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