|
|
|
|
| <!DOCTYPE html>
|
|
|
| <html lang="en" data-content_root="./">
|
| <head>
|
| <meta charset="utf-8" />
|
| <meta name="viewport" content="width=device-width, initial-scale=1.0" /><meta name="viewport" content="width=device-width, initial-scale=1" />
|
|
|
| <title>Code Overview — pgAdmin 4 8.6 documentation</title>
|
| <link rel="stylesheet" type="text/css" href="_static/pygments.css?v=fa44fd50" />
|
| <link rel="stylesheet" type="text/css" href="_static/style.css?v=d36593c3" />
|
|
|
| <script src="_static/documentation_options.js?v=d4c83366"></script>
|
| <script src="_static/doctools.js?v=9a2dae69"></script>
|
| <script src="_static/sphinx_highlight.js?v=dc90522c"></script>
|
|
|
| <script src="_static/sidebar.js"></script>
|
|
|
| <link rel="index" title="Index" href="genindex.html" />
|
| <link rel="search" title="Search" href="search.html" />
|
| <link rel="next" title="Coding Standards" href="coding_standards.html" />
|
| <link rel="prev" title="Submitting Pull Requests" href="submitting_pull_requests.html" />
|
| </head><body>
|
| <div class="related" role="navigation" aria-label="related navigation">
|
| <h3>Navigation</h3>
|
| <ul>
|
| <li class="right" style="margin-right: 10px">
|
| <a href="genindex.html" title="General Index"
|
| accesskey="I">index</a></li>
|
| <li class="right" >
|
| <a href="coding_standards.html" title="Coding Standards"
|
| accesskey="N">next</a> |</li>
|
| <li class="right" >
|
| <a href="submitting_pull_requests.html" title="Submitting Pull Requests"
|
| accesskey="P">previous</a> |</li>
|
| <li class="nav-item nav-item-0"><a href="index.html">pgAdmin 4 8.6 documentation</a> »</li>
|
| <li class="nav-item nav-item-1"><a href="contributions.html" accesskey="U">pgAdmin Project Contributions</a> »</li>
|
| <li class="nav-item nav-item-this"><a href="">Code Overview</a></li>
|
| </ul>
|
| </div>
|
|
|
| <div class="document">
|
| <div class="documentwrapper">
|
| <div class="bodywrapper">
|
| <div class="body" role="main">
|
|
|
| <section id="code-overview">
|
| <span id="id1"></span><h1><span class="target" id="index-0"></span>Code Overview<a class="headerlink" href="#code-overview" title="Link to this heading">¶</a></h1>
|
| <p>The bulk of pgAdmin is a Python web application written using the Flask framework
|
| on the backend, and HTML5 with CSS3,ReactJS on the front end. A
|
| desktop runtime is also included for users that prefer a desktop application to
|
| a web application, which is written using NWjs (Node Webkit).</p>
|
| <section id="runtime">
|
| <h2>Runtime<a class="headerlink" href="#runtime" title="Link to this heading">¶</a></h2>
|
| <p>The runtime is based on NWjs which integrates a browser and the Python server
|
| creating a standalone application. The source code can be found in the
|
| <strong>/runtime</strong> directory in the source tree.</p>
|
| </section>
|
| <section id="web-application">
|
| <h2>Web Application<a class="headerlink" href="#web-application" title="Link to this heading">¶</a></h2>
|
| <p>The web application forms the bulk of pgAdmin and can be found in the <strong>/web</strong>
|
| directory in the source tree. The main file is <strong>pgAdmin4.py</strong> which can be used
|
| to run the built-in standalone web server, or as a WSGI application for production
|
| use.</p>
|
| <section id="configuration">
|
| <h3>Configuration<a class="headerlink" href="#configuration" title="Link to this heading">¶</a></h3>
|
| <p>The core application configuration is found in <strong>config.py</strong>. This file includes
|
| all configurable settings for the application, along with descriptions of their
|
| use. It is essential that various settings are configured prior to deployment on
|
| a web server; these can be overridden in <strong>config_local.py</strong> or
|
| <strong>config_system.py</strong> (see the <a class="reference internal" href="config_py.html#config-py"><span class="std std-ref">config.py</span></a> documentation) to
|
| avoid modifying the main configuration file.</p>
|
| </section>
|
| <section id="user-settings">
|
| <h3>User Settings<a class="headerlink" href="#user-settings" title="Link to this heading">¶</a></h3>
|
| <p>When running in desktop mode, pgAdmin has a single, default user account that is
|
| used for the desktop user. When running in server mode, there may be unlimited
|
| users who are required to login prior to using the application. pgAdmin utilised
|
| the <strong>Flask-Security</strong> module to manage application security and users, and
|
| provides options for self-service password reset and password changes etc.</p>
|
| <p>Whether in desktop or server mode, each user’s settings are stored in a SQLite
|
| OR external database which is also used to store the user accounts. This is initially
|
| created using the <strong>setup.py</strong> script which will create the database file and
|
| schema within it, and add the first user account (with administrative
|
| privileges) and a default server group for them. A <strong>settings</strong> table is also
|
| used to store user configuration settings in a key-value fashion. Although not
|
| required, setting keys (or names) are typically formatted using forward slashes
|
| to artificially namespace values, much like the pgAdmin 3 settings files on Linux
|
| or Mac.</p>
|
| <p>Note that the local configuration must be setup prior to <strong>setup.py</strong> being run.
|
| The local configuration will determine how the script sets up the database,
|
| particularly with regard to desktop vs. server mode.</p>
|
| </section>
|
| </section>
|
| <section id="pgadmin-core">
|
| <h2>pgAdmin Core<a class="headerlink" href="#pgadmin-core" title="Link to this heading">¶</a></h2>
|
| <p>The heart of pgAdmin is the <strong>pgadmin</strong> package. This contains the globally
|
| available HTML templates used by the Jinja engine, as well as any global static
|
| files such as images, Javascript and CSS files that are used in multiple modules.</p>
|
| <p>The work of the package is handled in it’s constructor, <strong>__init__.py</strong>. This
|
| is responsible for setting up logging and authentication, dynamically loading
|
| other modules, and a few other tasks.</p>
|
| </section>
|
| <section id="modules">
|
| <h2>Modules<a class="headerlink" href="#modules" title="Link to this heading">¶</a></h2>
|
| <p>Units of functionality are added to pgAdmin through the addition of modules.
|
| Theses are Python object instance of classes, inherits the
|
| PgAdminModule class (a Flask Blueprint implementation), found in
|
| <strong>web/pgadmin/utils.py</strong>. It provide various hook points for other modules
|
| to utilise (primarily the default module - the browser).</p>
|
| <p>To be recognised as a module, a Python package must be created. This must:</p>
|
| <ol class="arabic simple">
|
| <li><p>Be placed within the <strong>web/pgadmin/</strong> directory, and</p></li>
|
| <li><p>Implements pgadmin.utils.PgAdminModule class</p></li>
|
| <li><p>An instance variable (generally - named <strong>blueprint</strong>) representing that
|
| particular class in that package.</p></li>
|
| </ol>
|
| <p>Each module may define a <strong>template</strong> and <strong>static</strong> directory for the Blueprint
|
| that it implements. To avoid name collisions, templates should be stored under
|
| a directory within the specified template directory, named after the module itself.
|
| For example, the <strong>browser</strong> module stores it’s templates in
|
| <strong>web/pgadmin/browser/templates/browser/</strong>. This does not apply to static files
|
| which may omit the second module name.</p>
|
| <p>In addition to defining the Blueprint, the <strong>views</strong> module is typically
|
| responsible for defining all the views that will be rendered in response to
|
| client requests, we must provide a REST API url(s) for these views. These must
|
| include appropriate route and security decorators. Take a look at the NodeView
|
| class, which uses the same approach as Flask’s MethodView, it can be found in
|
| <strong>web/pgadmin/browser/utils.py</strong>. This specific class is used by browser nodes
|
| for creating REST API url(s) for different operation on them. i.e. list, create,
|
| update, delete, fetch children, get
|
| statistics/reversed SQL/dependencies/dependents list for that node, etc. We can
|
| use the same class for other purpose too. You just need to inherit that class,
|
| and overload the member variables operations, parent_ids, ids, node_type, and
|
| then register it as node view with PgAdminModule instance.</p>
|
| <p>Most pgAdmin modules will also implement the <strong>hooks</strong> provided by the
|
| PgAdminModule class. This is responsible for providing hook points to integrate
|
| the module into the rest of the application - for example, a hook might tell
|
| the caller what CSS files need to be included on the rendered page, or what menu
|
| options to include and what they should do. Hook points need not exist if they
|
| are not required. It is the responsibility of the caller to ensure they are
|
| present before attempting to utilise them.</p>
|
| <p>Hooks currently implemented are:</p>
|
| <div class="highlight-python notranslate"><div class="highlight"><pre><span></span><span class="k">class</span> <span class="nc">MyModule</span><span class="p">(</span><span class="n">PgAdminModule</span><span class="p">):</span>
|
| <span class="w"> </span><span class="sd">"""</span>
|
| <span class="sd"> This is class implements the pgadmin.utils.PgAdminModule, and</span>
|
| <span class="sd"> implements the hooks</span>
|
| <span class="sd"> """</span>
|
|
|
| <span class="o">...</span>
|
|
|
| <span class="k">def</span> <span class="nf">get_own_stylesheets</span><span class="p">(</span><span class="bp">self</span><span class="p">):</span>
|
| <span class="w"> </span><span class="sd">"""</span>
|
| <span class="sd"> Returns:</span>
|
| <span class="sd"> list: the stylesheets used by this module, not including any</span>
|
| <span class="sd"> stylesheet needed by the submodules.</span>
|
| <span class="sd"> """</span>
|
| <span class="k">return</span> <span class="p">[</span><span class="n">url_for</span><span class="p">(</span><span class="s1">'static'</span><span class="p">,</span> <span class="s1">'css/mymodule.css'</span><span class="p">)]</span>
|
|
|
| <span class="k">def</span> <span class="nf">get_own_javascripts</span><span class="p">(</span><span class="bp">self</span><span class="p">):</span>
|
| <span class="w"> </span><span class="sd">"""</span>
|
| <span class="sd"> Returns:</span>
|
| <span class="sd"> list of dict:</span>
|
| <span class="sd"> - contains the name (representation for this javascript</span>
|
| <span class="sd"> module), path (url for it without .js suffix), deps (array of</span>
|
| <span class="sd"> dependents), exports window object by the javascript module,</span>
|
| <span class="sd"> and when (would you like to load this javascript), etc</span>
|
| <span class="sd"> information for this module, not including any script needed</span>
|
| <span class="sd"> by submodules.</span>
|
| <span class="sd"> """</span>
|
| <span class="k">return</span> <span class="p">[</span>
|
| <span class="p">{</span>
|
| <span class="s1">'name'</span><span class="p">:</span> <span class="s1">'pgadmin.extension.mymodule'</span><span class="p">,</span>
|
| <span class="s1">'path'</span><span class="p">:</span> <span class="n">url_for</span><span class="p">(</span><span class="s1">'static'</span><span class="p">,</span> <span class="n">filename</span><span class="o">=</span><span class="s1">'js/mymodule'</span><span class="p">),</span>
|
| <span class="s1">'exports'</span><span class="p">:</span> <span class="kc">None</span><span class="p">,</span>
|
| <span class="s1">'when'</span><span class="p">:</span> <span class="s1">'server'</span>
|
| <span class="p">}</span>
|
| <span class="p">]</span>
|
|
|
| <span class="k">def</span> <span class="nf">get_own_menuitems</span><span class="p">(</span><span class="bp">self</span><span class="p">):</span>
|
| <span class="w"> </span><span class="sd">"""</span>
|
| <span class="sd"> Returns:</span>
|
| <span class="sd"> dict: the menuitems for this module, not including</span>
|
| <span class="sd"> any needed from the submodules.</span>
|
| <span class="sd"> """</span>
|
| <span class="k">return</span> <span class="p">{</span>
|
| <span class="s1">'help_items'</span><span class="p">:</span> <span class="p">[</span>
|
| <span class="n">MenuItem</span><span class="p">(</span>
|
| <span class="n">name</span><span class="o">=</span><span class="s1">'mnu_mymodule_help'</span><span class="p">,</span>
|
| <span class="n">priority</span><span class="o">=</span><span class="mi">999</span><span class="p">,</span>
|
| <span class="c1"># We need to create javascript, which registers itself</span>
|
| <span class="c1"># as module</span>
|
| <span class="n">module</span><span class="o">=</span><span class="s2">"pgAdmin.MyModule"</span><span class="p">,</span>
|
| <span class="n">callback</span><span class="o">=</span><span class="s1">'about_show'</span><span class="p">,</span>
|
| <span class="n">icon</span><span class="o">=</span><span class="s1">'fa fa-info-circle'</span><span class="p">,</span>
|
| <span class="n">label</span><span class="o">=</span><span class="n">gettext</span><span class="p">(</span><span class="s1">'About MyModule'</span>
|
| <span class="p">)</span>
|
| <span class="p">]</span>
|
| <span class="p">}</span>
|
| <span class="k">def</span> <span class="nf">get_panels</span><span class="p">(</span><span class="bp">self</span><span class="p">):</span>
|
| <span class="w"> </span><span class="sd">"""</span>
|
| <span class="sd"> Returns:</span>
|
| <span class="sd"> list: a list of panel objects to add implemented in javascript</span>
|
| <span class="sd"> module</span>
|
| <span class="sd"> """</span>
|
| <span class="k">return</span> <span class="p">[]</span>
|
| <span class="o">...</span>
|
|
|
|
|
|
|
| <span class="n">blueprint</span> <span class="o">=</span> <span class="n">MyModule</span><span class="p">(</span><span class="s1">'mymodule'</span><span class="p">,</span> <span class="vm">__name__</span><span class="p">,</span> <span class="n">static_url_path</span><span class="o">=</span><span class="s1">'/static'</span><span class="p">)</span>
|
| </pre></div>
|
| </div>
|
| <p>pgAdmin Modules may include any additional Python modules that are required to
|
| fulfill their purpose, as required. They may also reference other dynamically
|
| loaded modules, but must use the defined hook points and fail gracefully in the
|
| event that a particular module is not present.</p>
|
| </section>
|
| <section id="nodes">
|
| <h2>Nodes<a class="headerlink" href="#nodes" title="Link to this heading">¶</a></h2>
|
| <p>Nodes are very similar to modules, it represents an individual node or,
|
| collection object on the object explorer treeview. To recognised as a node module, a
|
| Python package (along with javascript modules) must be created. This must:</p>
|
| <ol class="arabic simple">
|
| <li><p>Be placed within the <strong>web/pgadmin/browser/</strong> directory, and</p></li>
|
| <li><p>Implements the BrowserPluginModule, and registers the node view, which
|
| exposes required the REST APIs</p></li>
|
| <li><p>An instance of the class object</p></li>
|
| </ol>
|
| </section>
|
| <section id="front-end">
|
| <h2>Front End<a class="headerlink" href="#front-end" title="Link to this heading">¶</a></h2>
|
| <p>pgAdmin uses javascript extensively for the front-end implementation. It uses
|
| require.js to allow the lazy loading (or, say load only when required),
|
| ReactJS with CSS and MaterialUI for UI look and feel. We have
|
| divided each module in small chunks as much as possible. Not all javascript
|
| modules are required to be loaded (i.e. loading a javascript module for
|
| database will make sense only when a server node is loaded completely.) Please
|
| look at the javascript files node.js, browser.js, menu.js, panel.js, etc for
|
| better understanding of the code.</p>
|
| </section>
|
| </section>
|
|
|
|
|
| <div class="clearer"></div>
|
| </div>
|
| </div>
|
| </div>
|
| <div class="sphinxsidebar" role="navigation" aria-label="main navigation">
|
| <div class="sphinxsidebarwrapper">
|
| <div>
|
| <h3><a href="index.html">Table of Contents</a></h3>
|
| <ul>
|
| <li><a class="reference internal" href="#">Code Overview</a><ul>
|
| <li><a class="reference internal" href="#runtime">Runtime</a></li>
|
| <li><a class="reference internal" href="#web-application">Web Application</a><ul>
|
| <li><a class="reference internal" href="#configuration">Configuration</a></li>
|
| <li><a class="reference internal" href="#user-settings">User Settings</a></li>
|
| </ul>
|
| </li>
|
| <li><a class="reference internal" href="#pgadmin-core">pgAdmin Core</a></li>
|
| <li><a class="reference internal" href="#modules">Modules</a></li>
|
| <li><a class="reference internal" href="#nodes">Nodes</a></li>
|
| <li><a class="reference internal" href="#front-end">Front End</a></li>
|
| </ul>
|
| </li>
|
| </ul>
|
|
|
| </div>
|
| <h3><a href="index.html">Table of Contents</a></h3>
|
| <ul class="current">
|
| <li class="toctree-l1"><a class="reference internal" href="getting_started.html">Getting Started</a></li>
|
| <li class="toctree-l1"><a class="reference internal" href="external_database.html">External database for pgAdmin user settings</a></li>
|
| <li class="toctree-l1"><a class="reference internal" href="connecting.html">Connecting To A Server</a></li>
|
| <li class="toctree-l1"><a class="reference internal" href="managing_cluster_objects.html">Managing Cluster Objects</a></li>
|
| <li class="toctree-l1"><a class="reference internal" href="managing_database_objects.html">Managing Database Objects</a></li>
|
| <li class="toctree-l1"><a class="reference internal" href="modifying_tables.html">Creating or Modifying a Table</a></li>
|
| <li class="toctree-l1"><a class="reference internal" href="management_basics.html">Management Basics</a></li>
|
| <li class="toctree-l1"><a class="reference internal" href="backup_and_restore.html">Backup and Restore</a></li>
|
| <li class="toctree-l1"><a class="reference internal" href="developer_tools.html">Developer Tools</a></li>
|
| <li class="toctree-l1"><a class="reference internal" href="processes.html">Processes</a></li>
|
| <li class="toctree-l1"><a class="reference internal" href="pgagent.html">pgAgent</a></li>
|
| <li class="toctree-l1 current"><a class="reference internal" href="contributions.html">pgAdmin Project Contributions</a><ul class="current">
|
| <li class="toctree-l2"><a class="reference internal" href="submitting_pull_requests.html">Submitting Pull Requests</a></li>
|
| <li class="toctree-l2 current"><a class="current reference internal" href="#">Code Overview</a></li>
|
| <li class="toctree-l2"><a class="reference internal" href="coding_standards.html">Coding Standards</a></li>
|
| <li class="toctree-l2"><a class="reference internal" href="code_snippets.html">Code Snippets</a></li>
|
| <li class="toctree-l2"><a class="reference internal" href="code_review.html">Code Review Notes</a></li>
|
| <li class="toctree-l2"><a class="reference internal" href="translations.html">Translations</a></li>
|
| </ul>
|
| </li>
|
| <li class="toctree-l1"><a class="reference internal" href="release_notes.html">Release Notes</a></li>
|
| <li class="toctree-l1"><a class="reference internal" href="licence.html">Licence</a></li>
|
| </ul>
|
|
|
| <search id="searchbox" style="display: none" role="search">
|
| <h3 id="searchlabel">Quick search</h3>
|
| <div class="searchformwrapper">
|
| <form class="search" action="search.html" method="get">
|
| <input type="text" name="q" aria-labelledby="searchlabel" autocomplete="off" autocorrect="off" autocapitalize="off" spellcheck="false"/>
|
| <input type="submit" value="Go" />
|
| </form>
|
| </div>
|
| </search>
|
| <script>document.getElementById('searchbox').style.display = "block"</script>
|
| </div>
|
| <div id="sidebarbutton" title="Collapse sidebar">
|
| <span>«</span>
|
| </div>
|
|
|
| </div>
|
| <div class="clearer"></div>
|
| </div>
|
| <div class="related" role="navigation" aria-label="related navigation">
|
| <h3>Navigation</h3>
|
| <ul>
|
| <li class="right" style="margin-right: 10px">
|
| <a href="genindex.html" title="General Index"
|
| >index</a></li>
|
| <li class="right" >
|
| <a href="coding_standards.html" title="Coding Standards"
|
| >next</a> |</li>
|
| <li class="right" >
|
| <a href="submitting_pull_requests.html" title="Submitting Pull Requests"
|
| >previous</a> |</li>
|
| <li class="nav-item nav-item-0"><a href="index.html">pgAdmin 4 8.6 documentation</a> »</li>
|
| <li class="nav-item nav-item-1"><a href="contributions.html" >pgAdmin Project Contributions</a> »</li>
|
| <li class="nav-item nav-item-this"><a href="">Code Overview</a></li>
|
| </ul>
|
| </div>
|
| <div class="footer" role="contentinfo">
|
| <div class="related" role="navigation" aria-label="related navigation">
|
| <ul>
|
| <li class="left" style="margin-left: 10px">© Copyright (C) 2013 - 2024, The pgAdmin Development Team.</li>
|
| <li class="right" style="margin-right: 10px"><a href="genindex.html" title="General Index" accesskey="I">index</a></li>
|
| <li class="right" ><a href="coding_standards.html" title="Coding Standards" accesskey="N">next</a> |</li>
|
| <li class="right" ><a href="submitting_pull_requests.html" title="Submitting Pull Requests" accesskey="P">previous</a> |</li>
|
| </ul>
|
| </div>
|
| </div>
|
| </body>
|
| </html> |
