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Alternate Class Instrumentation
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SQLAlchemy 1.2 Documentation
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Release: <span class="version-num">1.2.19</span>
| Release Date: April 15, 2019
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<h1>SQLAlchemy 1.2 Documentation</h1>
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<li class="selected"><span class="link-container"><strong>Alternate Class Instrumentation</strong><a class="paramlink headerlink reference internal" href="#">¶</a></span><ul>
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<div class="section" id="module-sqlalchemy.ext.instrumentation">
<span id="alternate-class-instrumentation"></span><span id="instrumentation-toplevel"></span><h1>Alternate Class Instrumentation<a class="headerlink" href="#module-sqlalchemy.ext.instrumentation" title="Permalink to this headline">¶</a></h1>
<p>Extensible class instrumentation.</p>
<p>The <a class="reference internal" href="#module-sqlalchemy.ext.instrumentation" title="sqlalchemy.ext.instrumentation"><code class="xref py py-mod docutils literal notranslate"><span class="pre">sqlalchemy.ext.instrumentation</span></code></a> package provides for alternate
systems of class instrumentation within the ORM. Class instrumentation
refers to how the ORM places attributes on the class which maintain
data and track changes to that data, as well as event hooks installed
on the class.</p>
<div class="admonition note">
<p class="admonition-title">Note</p>
<p>The extension package is provided for the benefit of integration
with other object management packages, which already perform
their own instrumentation. It is not intended for general use.</p>
</div>
<p>For examples of how the instrumentation extension is used,
see the example <a class="reference internal" href="../examples.html#examples-instrumentation"><span class="std std-ref">Attribute Instrumentation</span></a>.</p>
<div class="section" id="api-reference">
<h2>API Reference<a class="headerlink" href="#api-reference" title="Permalink to this headline">¶</a></h2>
<dl class="data">
<dt id="sqlalchemy.ext.instrumentation.INSTRUMENTATION_MANAGER">
<code class="descclassname">sqlalchemy.ext.instrumentation.</code><code class="descname">INSTRUMENTATION_MANAGER</code><em class="property"> = '__sa_instrumentation_manager__'</em><a class="headerlink" href="#sqlalchemy.ext.instrumentation.INSTRUMENTATION_MANAGER" title="Permalink to this definition">¶</a></dt>
<dd><p>Attribute, elects custom instrumentation when present on a mapped class.</p>
<p>Allows a class to specify a slightly or wildly different technique for
tracking changes made to mapped attributes and collections.</p>
<p>Only one instrumentation implementation is allowed in a given object
inheritance hierarchy.</p>
<p>The value of this attribute must be a callable and will be passed a class
object. The callable must return one of:</p>
<blockquote>
<div><ul class="simple">
<li><p>An instance of an InstrumentationManager or subclass</p></li>
<li><p>An object implementing all or some of InstrumentationManager (TODO)</p></li>
<li><p>A dictionary of callables, implementing all or some of the above (TODO)</p></li>
<li><p>An instance of a ClassManager or subclass</p></li>
</ul>
</div></blockquote>
<p>This attribute is consulted by SQLAlchemy instrumentation
resolution, once the <a class="reference internal" href="#module-sqlalchemy.ext.instrumentation" title="sqlalchemy.ext.instrumentation"><code class="xref py py-mod docutils literal notranslate"><span class="pre">sqlalchemy.ext.instrumentation</span></code></a> module
has been imported. If custom finders are installed in the global
instrumentation_finders list, they may or may not choose to honor this
attribute.</p>
</dd></dl>
<dl class="class">
<dt id="sqlalchemy.orm.instrumentation.InstrumentationFactory">
<em class="property">class </em><code class="descclassname">sqlalchemy.orm.instrumentation.</code><code class="descname">InstrumentationFactory</code><a class="headerlink" href="#sqlalchemy.orm.instrumentation.InstrumentationFactory" title="Permalink to this definition">¶</a></dt>
<dd><p>Factory for new ClassManager instances.</p>
</dd></dl>
<dl class="class">
<dt id="sqlalchemy.ext.instrumentation.InstrumentationManager">
<em class="property">class </em><code class="descclassname">sqlalchemy.ext.instrumentation.</code><code class="descname">InstrumentationManager</code><span class="sig-paren">(</span><em>class_</em><span class="sig-paren">)</span><a class="headerlink" href="#sqlalchemy.ext.instrumentation.InstrumentationManager" title="Permalink to this definition">¶</a></dt>
<dd><p>User-defined class instrumentation extension.</p>
<p><a class="reference internal" href="#sqlalchemy.ext.instrumentation.InstrumentationManager" title="sqlalchemy.ext.instrumentation.InstrumentationManager"><code class="xref py py-class docutils literal notranslate"><span class="pre">InstrumentationManager</span></code></a> can be subclassed in order
to change
how class instrumentation proceeds. This class exists for
the purposes of integration with other object management
frameworks which would like to entirely modify the
instrumentation methodology of the ORM, and is not intended
for regular usage. For interception of class instrumentation
events, see <a class="reference internal" href="../events.html#sqlalchemy.orm.events.InstrumentationEvents" title="sqlalchemy.orm.events.InstrumentationEvents"><code class="xref py py-class docutils literal notranslate"><span class="pre">InstrumentationEvents</span></code></a>.</p>
<p>The API for this class should be considered as semi-stable,
and may change slightly with new releases.</p>
<dl class="method">
<dt id="sqlalchemy.ext.instrumentation.InstrumentationManager.dict_getter">
<code class="descname">dict_getter</code><span class="sig-paren">(</span><em>class_</em><span class="sig-paren">)</span><a class="headerlink" href="#sqlalchemy.ext.instrumentation.InstrumentationManager.dict_getter" title="Permalink to this definition">¶</a></dt>
<dd></dd></dl>
<dl class="method">
<dt id="sqlalchemy.ext.instrumentation.InstrumentationManager.dispose">
<code class="descname">dispose</code><span class="sig-paren">(</span><em>class_</em>, <em>manager</em><span class="sig-paren">)</span><a class="headerlink" href="#sqlalchemy.ext.instrumentation.InstrumentationManager.dispose" title="Permalink to this definition">¶</a></dt>
<dd></dd></dl>
<dl class="method">
<dt id="sqlalchemy.ext.instrumentation.InstrumentationManager.get_instance_dict">
<code class="descname">get_instance_dict</code><span class="sig-paren">(</span><em>class_</em>, <em>instance</em><span class="sig-paren">)</span><a class="headerlink" href="#sqlalchemy.ext.instrumentation.InstrumentationManager.get_instance_dict" title="Permalink to this definition">¶</a></dt>
<dd></dd></dl>
<dl class="method">
<dt id="sqlalchemy.ext.instrumentation.InstrumentationManager.initialize_instance_dict">
<code class="descname">initialize_instance_dict</code><span class="sig-paren">(</span><em>class_</em>, <em>instance</em><span class="sig-paren">)</span><a class="headerlink" href="#sqlalchemy.ext.instrumentation.InstrumentationManager.initialize_instance_dict" title="Permalink to this definition">¶</a></dt>
<dd></dd></dl>
<dl class="method">
<dt id="sqlalchemy.ext.instrumentation.InstrumentationManager.install_descriptor">
<code class="descname">install_descriptor</code><span class="sig-paren">(</span><em>class_</em>, <em>key</em>, <em>inst</em><span class="sig-paren">)</span><a class="headerlink" href="#sqlalchemy.ext.instrumentation.InstrumentationManager.install_descriptor" title="Permalink to this definition">¶</a></dt>
<dd></dd></dl>
<dl class="method">
<dt id="sqlalchemy.ext.instrumentation.InstrumentationManager.install_member">
<code class="descname">install_member</code><span class="sig-paren">(</span><em>class_</em>, <em>key</em>, <em>implementation</em><span class="sig-paren">)</span><a class="headerlink" href="#sqlalchemy.ext.instrumentation.InstrumentationManager.install_member" title="Permalink to this definition">¶</a></dt>
<dd></dd></dl>
<dl class="method">
<dt id="sqlalchemy.ext.instrumentation.InstrumentationManager.install_state">
<code class="descname">install_state</code><span class="sig-paren">(</span><em>class_</em>, <em>instance</em>, <em>state</em><span class="sig-paren">)</span><a class="headerlink" href="#sqlalchemy.ext.instrumentation.InstrumentationManager.install_state" title="Permalink to this definition">¶</a></dt>
<dd></dd></dl>
<dl class="method">
<dt id="sqlalchemy.ext.instrumentation.InstrumentationManager.instrument_attribute">
<code class="descname">instrument_attribute</code><span class="sig-paren">(</span><em>class_</em>, <em>key</em>, <em>inst</em><span class="sig-paren">)</span><a class="headerlink" href="#sqlalchemy.ext.instrumentation.InstrumentationManager.instrument_attribute" title="Permalink to this definition">¶</a></dt>
<dd></dd></dl>
<dl class="method">
<dt id="sqlalchemy.ext.instrumentation.InstrumentationManager.instrument_collection_class">
<code class="descname">instrument_collection_class</code><span class="sig-paren">(</span><em>class_</em>, <em>key</em>, <em>collection_class</em><span class="sig-paren">)</span><a class="headerlink" href="#sqlalchemy.ext.instrumentation.InstrumentationManager.instrument_collection_class" title="Permalink to this definition">¶</a></dt>
<dd></dd></dl>
<dl class="method">
<dt id="sqlalchemy.ext.instrumentation.InstrumentationManager.manage">
<code class="descname">manage</code><span class="sig-paren">(</span><em>class_</em>, <em>manager</em><span class="sig-paren">)</span><a class="headerlink" href="#sqlalchemy.ext.instrumentation.InstrumentationManager.manage" title="Permalink to this definition">¶</a></dt>
<dd></dd></dl>
<dl class="method">
<dt id="sqlalchemy.ext.instrumentation.InstrumentationManager.manager_getter">
<code class="descname">manager_getter</code><span class="sig-paren">(</span><em>class_</em><span class="sig-paren">)</span><a class="headerlink" href="#sqlalchemy.ext.instrumentation.InstrumentationManager.manager_getter" title="Permalink to this definition">¶</a></dt>
<dd></dd></dl>
<dl class="method">
<dt id="sqlalchemy.ext.instrumentation.InstrumentationManager.post_configure_attribute">
<code class="descname">post_configure_attribute</code><span class="sig-paren">(</span><em>class_</em>, <em>key</em>, <em>inst</em><span class="sig-paren">)</span><a class="headerlink" href="#sqlalchemy.ext.instrumentation.InstrumentationManager.post_configure_attribute" title="Permalink to this definition">¶</a></dt>
<dd></dd></dl>
<dl class="method">
<dt id="sqlalchemy.ext.instrumentation.InstrumentationManager.remove_state">
<code class="descname">remove_state</code><span class="sig-paren">(</span><em>class_</em>, <em>instance</em><span class="sig-paren">)</span><a class="headerlink" href="#sqlalchemy.ext.instrumentation.InstrumentationManager.remove_state" title="Permalink to this definition">¶</a></dt>
<dd></dd></dl>
<dl class="method">
<dt id="sqlalchemy.ext.instrumentation.InstrumentationManager.state_getter">
<code class="descname">state_getter</code><span class="sig-paren">(</span><em>class_</em><span class="sig-paren">)</span><a class="headerlink" href="#sqlalchemy.ext.instrumentation.InstrumentationManager.state_getter" title="Permalink to this definition">¶</a></dt>
<dd></dd></dl>
<dl class="method">
<dt id="sqlalchemy.ext.instrumentation.InstrumentationManager.uninstall_descriptor">
<code class="descname">uninstall_descriptor</code><span class="sig-paren">(</span><em>class_</em>, <em>key</em><span class="sig-paren">)</span><a class="headerlink" href="#sqlalchemy.ext.instrumentation.InstrumentationManager.uninstall_descriptor" title="Permalink to this definition">¶</a></dt>
<dd></dd></dl>
<dl class="method">
<dt id="sqlalchemy.ext.instrumentation.InstrumentationManager.uninstall_member">
<code class="descname">uninstall_member</code><span class="sig-paren">(</span><em>class_</em>, <em>key</em><span class="sig-paren">)</span><a class="headerlink" href="#sqlalchemy.ext.instrumentation.InstrumentationManager.uninstall_member" title="Permalink to this definition">¶</a></dt>
<dd></dd></dl>
</dd></dl>
<dl class="data">
<dt id="sqlalchemy.ext.instrumentation.instrumentation_finders">
<code class="descclassname">sqlalchemy.ext.instrumentation.</code><code class="descname">instrumentation_finders</code><em class="property"> = [<function find_native_user_instrumentation_hook>]</em><a class="headerlink" href="#sqlalchemy.ext.instrumentation.instrumentation_finders" title="Permalink to this definition">¶</a></dt>
<dd><p>An extensible sequence of callables which return instrumentation
implementations</p>
<p>When a class is registered, each callable will be passed a class object.
If None is returned, the
next finder in the sequence is consulted. Otherwise the return must be an
instrumentation factory that follows the same guidelines as
sqlalchemy.ext.instrumentation.INSTRUMENTATION_MANAGER.</p>
<p>By default, the only finder is find_native_user_instrumentation_hook, which
searches for INSTRUMENTATION_MANAGER. If all finders return None, standard
ClassManager instrumentation is used.</p>
</dd></dl>
<dl class="class">
<dt id="sqlalchemy.ext.instrumentation.ExtendedInstrumentationRegistry">
<em class="property">class </em><code class="descclassname">sqlalchemy.ext.instrumentation.</code><code class="descname">ExtendedInstrumentationRegistry</code><a class="headerlink" href="#sqlalchemy.ext.instrumentation.ExtendedInstrumentationRegistry" title="Permalink to this definition">¶</a></dt>
<dd><p>Bases: <a class="reference internal" href="#sqlalchemy.orm.instrumentation.InstrumentationFactory" title="sqlalchemy.orm.instrumentation.InstrumentationFactory"><code class="xref py py-class docutils literal notranslate"><span class="pre">sqlalchemy.orm.instrumentation.InstrumentationFactory</span></code></a></p>
<p>Extends <a class="reference internal" href="#sqlalchemy.orm.instrumentation.InstrumentationFactory" title="sqlalchemy.orm.instrumentation.InstrumentationFactory"><code class="xref py py-class docutils literal notranslate"><span class="pre">InstrumentationFactory</span></code></a> with additional
bookkeeping, to accommodate multiple types of
class managers.</p>
</dd></dl>
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