{"title":"Como implementar um backend de template personalizado","version":"6.1","locale":"pt-br","docname":"howto/custom-template-backend","url":"/pt-br/6.1/howto/custom-template-backend/","canonical":"https://djangodocs.dev/pt-br/6.1/howto/custom-template-backend/","summary":"Backends personalizados Link para este cabeçalho # Aqui está como implementar um backend de template personalizado para utilizar um sistema de template. Um backend…","html":"<h1>Como implementar um backend de template personalizado<a class=\"heading-anchor\" href=\"#how-to-implement-a-custom-template-backend\"><span class=\"visually-hidden\">Link para este cabeçalho</span><span aria-hidden=\"true\">#</span></a></h1>\n<section id=\"custom-backends\">\n<h2>Backends personalizados<a class=\"heading-anchor\" href=\"#custom-backends\"><span class=\"visually-hidden\">Link para este cabeçalho</span><span aria-hidden=\"true\">#</span></a></h2>\n<p>Aqui está como implementar um backend de template personalizado para utilizar um sistema de template. Um backend de template precisa herdar de <code class=\"docutils literal notranslate\"><span class=\"pre\">django.template.backends.base.BaseEngine</span></code>. Precisa implementar <code class=\"docutils literal notranslate\"><span class=\"pre\">get_template()</span></code> e opcionalmente <code class=\"docutils literal notranslate\"><span class=\"pre\">from_string()</span></code>. Aqui está um exemplo para a biblioteca de template fícticia <code class=\"docutils literal notranslate\"><span class=\"pre\">foobar</span></code>:</p>\n<div class=\"code-block\" data-language=\"default\"><div class=\"code-block-toolbar\"><span class=\"code-block-language\">Code</span><button type=\"button\" class=\"copy-button\" data-copy hidden><span class=\"copy-button-label\">Copy</span></button></div><pre role=\"group\" tabindex=\"0\" aria-label=\"Code code\"><code><span class=\"kn\">from</span><span class=\"w\"> </span><span class=\"nn\">django.template</span><span class=\"w\"> </span><span class=\"kn\">import</span> <span class=\"n\">TemplateDoesNotExist</span><span class=\"p\">,</span> <span class=\"n\">TemplateSyntaxError</span>\n<span class=\"kn\">from</span><span class=\"w\"> </span><span class=\"nn\">django.template.backends.base</span><span class=\"w\"> </span><span class=\"kn\">import</span> <span class=\"n\">BaseEngine</span>\n<span class=\"kn\">from</span><span class=\"w\"> </span><span class=\"nn\">django.template.backends.utils</span><span class=\"w\"> </span><span class=\"kn\">import</span> <span class=\"n\">csrf_input_lazy</span><span class=\"p\">,</span> <span class=\"n\">csrf_token_lazy</span>\n\n<span class=\"kn\">import</span><span class=\"w\"> </span><span class=\"nn\">foobar</span>\n\n\n<span class=\"k\">class</span><span class=\"w\"> </span><span class=\"nc\">FooBar</span><span class=\"p\">(</span><span class=\"n\">BaseEngine</span><span class=\"p\">):</span>\n    <span class=\"c1\"># Name of the subdirectory containing the templates for this engine</span>\n    <span class=\"c1\"># inside an installed application.</span>\n    <span class=\"n\">app_dirname</span> <span class=\"o\">=</span> <span class=\"s2\">&quot;foobar&quot;</span>\n\n    <span class=\"k\">def</span><span class=\"w\"> </span><span class=\"fm\">__init__</span><span class=\"p\">(</span><span class=\"bp\">self</span><span class=\"p\">,</span> <span class=\"n\">params</span><span class=\"p\">):</span>\n        <span class=\"n\">params</span> <span class=\"o\">=</span> <span class=\"n\">params</span><span class=\"o\">.</span><span class=\"n\">copy</span><span class=\"p\">()</span>\n        <span class=\"n\">options</span> <span class=\"o\">=</span> <span class=\"n\">params</span><span class=\"o\">.</span><span class=\"n\">pop</span><span class=\"p\">(</span><span class=\"s2\">&quot;OPTIONS&quot;</span><span class=\"p\">)</span><span class=\"o\">.</span><span class=\"n\">copy</span><span class=\"p\">()</span>\n        <span class=\"nb\">super</span><span class=\"p\">()</span><span class=\"o\">.</span><span class=\"fm\">__init__</span><span class=\"p\">(</span><span class=\"n\">params</span><span class=\"p\">)</span>\n\n        <span class=\"bp\">self</span><span class=\"o\">.</span><span class=\"n\">engine</span> <span class=\"o\">=</span> <span class=\"n\">foobar</span><span class=\"o\">.</span><span class=\"n\">Engine</span><span class=\"p\">(</span><span class=\"o\">**</span><span class=\"n\">options</span><span class=\"p\">)</span>\n\n    <span class=\"k\">def</span><span class=\"w\"> </span><span class=\"nf\">from_string</span><span class=\"p\">(</span><span class=\"bp\">self</span><span class=\"p\">,</span> <span class=\"n\">template_code</span><span class=\"p\">):</span>\n        <span class=\"k\">try</span><span class=\"p\">:</span>\n            <span class=\"k\">return</span> <span class=\"n\">Template</span><span class=\"p\">(</span><span class=\"bp\">self</span><span class=\"o\">.</span><span class=\"n\">engine</span><span class=\"o\">.</span><span class=\"n\">from_string</span><span class=\"p\">(</span><span class=\"n\">template_code</span><span class=\"p\">))</span>\n        <span class=\"k\">except</span> <span class=\"n\">foobar</span><span class=\"o\">.</span><span class=\"n\">TemplateCompilationFailed</span> <span class=\"k\">as</span> <span class=\"n\">exc</span><span class=\"p\">:</span>\n            <span class=\"k\">raise</span> <span class=\"n\">TemplateSyntaxError</span><span class=\"p\">(</span><span class=\"n\">exc</span><span class=\"o\">.</span><span class=\"n\">args</span><span class=\"p\">)</span>\n\n    <span class=\"k\">def</span><span class=\"w\"> </span><span class=\"nf\">get_template</span><span class=\"p\">(</span><span class=\"bp\">self</span><span class=\"p\">,</span> <span class=\"n\">template_name</span><span class=\"p\">):</span>\n        <span class=\"k\">try</span><span class=\"p\">:</span>\n            <span class=\"k\">return</span> <span class=\"n\">Template</span><span class=\"p\">(</span><span class=\"bp\">self</span><span class=\"o\">.</span><span class=\"n\">engine</span><span class=\"o\">.</span><span class=\"n\">get_template</span><span class=\"p\">(</span><span class=\"n\">template_name</span><span class=\"p\">))</span>\n        <span class=\"k\">except</span> <span class=\"n\">foobar</span><span class=\"o\">.</span><span class=\"n\">TemplateNotFound</span> <span class=\"k\">as</span> <span class=\"n\">exc</span><span class=\"p\">:</span>\n            <span class=\"k\">raise</span> <span class=\"n\">TemplateDoesNotExist</span><span class=\"p\">(</span><span class=\"n\">exc</span><span class=\"o\">.</span><span class=\"n\">args</span><span class=\"p\">,</span> <span class=\"n\">backend</span><span class=\"o\">=</span><span class=\"bp\">self</span><span class=\"p\">)</span>\n        <span class=\"k\">except</span> <span class=\"n\">foobar</span><span class=\"o\">.</span><span class=\"n\">TemplateCompilationFailed</span> <span class=\"k\">as</span> <span class=\"n\">exc</span><span class=\"p\">:</span>\n            <span class=\"k\">raise</span> <span class=\"n\">TemplateSyntaxError</span><span class=\"p\">(</span><span class=\"n\">exc</span><span class=\"o\">.</span><span class=\"n\">args</span><span class=\"p\">)</span>\n\n\n<span class=\"k\">class</span><span class=\"w\"> </span><span class=\"nc\">Template</span><span class=\"p\">:</span>\n    <span class=\"k\">def</span><span class=\"w\"> </span><span class=\"fm\">__init__</span><span class=\"p\">(</span><span class=\"bp\">self</span><span class=\"p\">,</span> <span class=\"n\">template</span><span class=\"p\">):</span>\n        <span class=\"bp\">self</span><span class=\"o\">.</span><span class=\"n\">template</span> <span class=\"o\">=</span> <span class=\"n\">template</span>\n\n    <span class=\"k\">def</span><span class=\"w\"> </span><span class=\"nf\">render</span><span class=\"p\">(</span><span class=\"bp\">self</span><span class=\"p\">,</span> <span class=\"n\">context</span><span class=\"o\">=</span><span class=\"kc\">None</span><span class=\"p\">,</span> <span class=\"n\">request</span><span class=\"o\">=</span><span class=\"kc\">None</span><span class=\"p\">):</span>\n        <span class=\"k\">if</span> <span class=\"n\">context</span> <span class=\"ow\">is</span> <span class=\"kc\">None</span><span class=\"p\">:</span>\n            <span class=\"n\">context</span> <span class=\"o\">=</span> <span class=\"p\">{}</span>\n        <span class=\"k\">if</span> <span class=\"n\">request</span> <span class=\"ow\">is</span> <span class=\"ow\">not</span> <span class=\"kc\">None</span><span class=\"p\">:</span>\n            <span class=\"n\">context</span><span class=\"p\">[</span><span class=\"s2\">&quot;request&quot;</span><span class=\"p\">]</span> <span class=\"o\">=</span> <span class=\"n\">request</span>\n            <span class=\"n\">context</span><span class=\"p\">[</span><span class=\"s2\">&quot;csrf_input&quot;</span><span class=\"p\">]</span> <span class=\"o\">=</span> <span class=\"n\">csrf_input_lazy</span><span class=\"p\">(</span><span class=\"n\">request</span><span class=\"p\">)</span>\n            <span class=\"n\">context</span><span class=\"p\">[</span><span class=\"s2\">&quot;csrf_token&quot;</span><span class=\"p\">]</span> <span class=\"o\">=</span> <span class=\"n\">csrf_token_lazy</span><span class=\"p\">(</span><span class=\"n\">request</span><span class=\"p\">)</span>\n        <span class=\"k\">return</span> <span class=\"bp\">self</span><span class=\"o\">.</span><span class=\"n\">template</span><span class=\"o\">.</span><span class=\"n\">render</span><span class=\"p\">(</span><span class=\"n\">context</span><span class=\"p\">)</span>\n</code></pre></div>\n<p>Veja a <a class=\"reference external\" href=\"https://github.com/django/deps/blob/main/final/0182-multiple-template-engines.rst\">DEP 182</a> para mais informações.</p>\n</section>\n<section id=\"debug-integration-for-custom-engines\">\n<span id=\"template-debug-integration\"></span><h2>Debugar a integração para motores personalizados<a class=\"heading-anchor\" href=\"#debug-integration-for-custom-engines\"><span class=\"visually-hidden\">Link para este cabeçalho</span><span aria-hidden=\"true\">#</span></a></h2>\n<p>A página de debug do Django tem hooks para prover informações detalhadas quando um erro de template é levantado. Motores de template customizados podem utilizar estes hooks para melhoras as informações de traceback que aparecem aos usuários. Os seguintes hooks estão disponíveis:</p>\n<section id=\"template-postmortem\">\n<span id=\"id1\"></span><h3>Template postmortem<a class=\"heading-anchor\" href=\"#template-postmortem\"><span class=\"visually-hidden\">Link para este cabeçalho</span><span aria-hidden=\"true\">#</span></a></h3>\n<p>O postmortem aparece quando <a class=\"reference internal\" href=\"/pt-br/6.1/topics/templates/#django.template.TemplateDoesNotExist\" title=\"django.template.TemplateDoesNotExist\"><code class=\"xref py py-exc docutils literal notranslate\"><span class=\"pre\">TemplateDoesNotExist</span></code></a> é levantado. Ele lista os motores de template e loaders que foram utilizados ao tentar encontrar o template informado. Por exemplo, se dois motores Django estão configurados, o postmortem será parecido com:</p>\n<img alt=\"/pt-br/6.1/_images/postmortem.png\" src=\"/pt-br/6.1/_images/postmortem.png\" />\n<p>Motores personalizados podem popular o postmortem por passar o <code class=\"docutils literal notranslate\"><span class=\"pre\">backend</span></code> e os argumentos <code class=\"docutils literal notranslate\"><span class=\"pre\">tried</span></code> ao levantar <a class=\"reference internal\" href=\"/pt-br/6.1/topics/templates/#django.template.TemplateDoesNotExist\" title=\"django.template.TemplateDoesNotExist\"><code class=\"xref py py-exc docutils literal notranslate\"><span class=\"pre\">TemplateDoesNotExist</span></code></a>. Backends que utilizam o postmortem  <span class=\"xref std std-ref\">devem especificar uma origem 1</span> ao objeto template.</p>\n</section>\n<section id=\"contextual-line-information\">\n<h3>Linha de informações contextuais<a class=\"heading-anchor\" href=\"#contextual-line-information\"><span class=\"visually-hidden\">Link para este cabeçalho</span><span aria-hidden=\"true\">#</span></a></h3>\n<p>Se um erro acontece durante o tratamento ou renderização do template, o Django pode mostrar a linha em que o erro ocorreu. Por exemplo:</p>\n<img alt=\"/pt-br/6.1/_images/template-lines.png\" src=\"/pt-br/6.1/_images/template-lines.png\" />\n<p>Motores personalizados podem popular esta informação por definir um atributo <code class=\"docutils literal notranslate\"><span class=\"pre\">template_debug</span></code> nas exceções levantadas durante o tratamento e renderização. Esse atributo é um <a class=\"reference external\" href=\"https://docs.python.org/3/library/stdtypes.html#dict\" title=\"(em Python v3.14)\"><code class=\"xref py py-class docutils literal notranslate\"><span class=\"pre\">dict</span></code></a> com os seguintes valores:</p>\n<ul class=\"simple\">\n<li><p><code class=\"docutils literal notranslate\"><span class=\"pre\">'name'</span></code>: O nome do template onde a exceção ocorreu.</p></li>\n<li><p><code class=\"docutils literal notranslate\"><span class=\"pre\">'message'</span></code>: A mensagem de exceção.</p></li>\n<li><p><code class=\"docutils literal notranslate\"><span class=\"pre\">'source_lines'</span></code>: As linhas antes, depois, e incluindo a linha que exceção aconteceu. Isso é para contexto, por isso não teve mais do que cerca de 20 linhas.</p></li>\n<li><p><code class=\"docutils literal notranslate\"><span class=\"pre\">'line'</span></code>: O número da linha em que a exceção aconteceu.</p></li>\n<li><p><code class=\"docutils literal notranslate\"><span class=\"pre\">'before'</span></code>: O conteúdo na linha de erro anterior ao token que levantou o erro.</p></li>\n<li><p><code class=\"docutils literal notranslate\"><span class=\"pre\">'during'</span></code>: O token que levantou o erro.</p></li>\n<li><p><code class=\"docutils literal notranslate\"><span class=\"pre\">'after'</span></code>: O conteúdo da linha de erro posterior ao token que levantou o erro.</p></li>\n<li><p><code class=\"docutils literal notranslate\"><span class=\"pre\">'total'</span></code>: O número de linhas em <code class=\"docutils literal notranslate\"><span class=\"pre\">source_lines</span></code>.</p></li>\n<li><p><code class=\"docutils literal notranslate\"><span class=\"pre\">'top'</span></code>: O número da linha onde <code class=\"docutils literal notranslate\"><span class=\"pre\">source_lines</span></code> começa.</p></li>\n<li><p><code class=\"docutils literal notranslate\"><span class=\"pre\">'bottom'</span></code>: O número da linha onde <code class=\"docutils literal notranslate\"><span class=\"pre\">source_lines</span></code> termina.</p></li>\n</ul>\n<p>Dado o seguinte erro de template, <code class=\"docutils literal notranslate\"><span class=\"pre\">template_debug</span></code> se parecerá com:</p>\n<div class=\"code-block\" data-language=\"default\"><div class=\"code-block-toolbar\"><span class=\"code-block-language\">Code</span><button type=\"button\" class=\"copy-button\" data-copy hidden><span class=\"copy-button-label\">Copy</span></button></div><pre role=\"group\" tabindex=\"0\" aria-label=\"Code code\"><code><span class=\"p\">{</span>\n    <span class=\"s2\">&quot;name&quot;</span><span class=\"p\">:</span> <span class=\"s2\">&quot;/path/to/template.html&quot;</span><span class=\"p\">,</span>\n    <span class=\"s2\">&quot;message&quot;</span><span class=\"p\">:</span> <span class=\"s2\">&quot;Invalid block tag: &#39;syntax&#39;&quot;</span><span class=\"p\">,</span>\n    <span class=\"s2\">&quot;source_lines&quot;</span><span class=\"p\">:</span> <span class=\"p\">[</span>\n        <span class=\"p\">(</span><span class=\"mi\">1</span><span class=\"p\">,</span> <span class=\"s2\">&quot;some</span><span class=\"se\">\\n</span><span class=\"s2\">&quot;</span><span class=\"p\">),</span>\n        <span class=\"p\">(</span><span class=\"mi\">2</span><span class=\"p\">,</span> <span class=\"s2\">&quot;lines</span><span class=\"se\">\\n</span><span class=\"s2\">&quot;</span><span class=\"p\">),</span>\n        <span class=\"p\">(</span><span class=\"mi\">3</span><span class=\"p\">,</span> <span class=\"s2\">&quot;before</span><span class=\"se\">\\n</span><span class=\"s2\">&quot;</span><span class=\"p\">),</span>\n        <span class=\"p\">(</span><span class=\"mi\">4</span><span class=\"p\">,</span> <span class=\"s2\">&quot;Hello {</span><span class=\"si\">% s</span><span class=\"s2\">yntax error %} {{ world }}</span><span class=\"se\">\\n</span><span class=\"s2\">&quot;</span><span class=\"p\">),</span>\n        <span class=\"p\">(</span><span class=\"mi\">5</span><span class=\"p\">,</span> <span class=\"s2\">&quot;some</span><span class=\"se\">\\n</span><span class=\"s2\">&quot;</span><span class=\"p\">),</span>\n        <span class=\"p\">(</span><span class=\"mi\">6</span><span class=\"p\">,</span> <span class=\"s2\">&quot;lines</span><span class=\"se\">\\n</span><span class=\"s2\">&quot;</span><span class=\"p\">),</span>\n        <span class=\"p\">(</span><span class=\"mi\">7</span><span class=\"p\">,</span> <span class=\"s2\">&quot;after</span><span class=\"se\">\\n</span><span class=\"s2\">&quot;</span><span class=\"p\">),</span>\n        <span class=\"p\">(</span><span class=\"mi\">8</span><span class=\"p\">,</span> <span class=\"s2\">&quot;&quot;</span><span class=\"p\">),</span>\n    <span class=\"p\">],</span>\n    <span class=\"s2\">&quot;line&quot;</span><span class=\"p\">:</span> <span class=\"mi\">4</span><span class=\"p\">,</span>\n    <span class=\"s2\">&quot;before&quot;</span><span class=\"p\">:</span> <span class=\"s2\">&quot;Hello &quot;</span><span class=\"p\">,</span>\n    <span class=\"s2\">&quot;during&quot;</span><span class=\"p\">:</span> <span class=\"s2\">&quot;{</span><span class=\"si\">% s</span><span class=\"s2\">yntax error %}&quot;</span><span class=\"p\">,</span>\n    <span class=\"s2\">&quot;after&quot;</span><span class=\"p\">:</span> <span class=\"s2\">&quot; {{ world }}</span><span class=\"se\">\\n</span><span class=\"s2\">&quot;</span><span class=\"p\">,</span>\n    <span class=\"s2\">&quot;total&quot;</span><span class=\"p\">:</span> <span class=\"mi\">9</span><span class=\"p\">,</span>\n    <span class=\"s2\">&quot;bottom&quot;</span><span class=\"p\">:</span> <span class=\"mi\">9</span><span class=\"p\">,</span>\n    <span class=\"s2\">&quot;top&quot;</span><span class=\"p\">:</span> <span class=\"mi\">1</span><span class=\"p\">,</span>\n<span class=\"p\">}</span>\n</code></pre></div>\n</section>\n<section id=\"origin-api-and-3rd-party-integration\">\n<span id=\"template-origin-api\"></span><h3>API de Origem e integração com terceiros<a class=\"heading-anchor\" href=\"#origin-api-and-3rd-party-integration\"><span class=\"visually-hidden\">Link para este cabeçalho</span><span aria-hidden=\"true\">#</span></a></h3>\n<p>Django templates have an <a class=\"reference internal\" href=\"/pt-br/6.1/ref/templates/api/#django.template.base.Origin\" title=\"django.template.base.Origin\"><code class=\"xref py py-class docutils literal notranslate\"><span class=\"pre\">Origin</span></code></a> object available\nthrough the <code class=\"docutils literal notranslate\"><span class=\"pre\">template.origin</span></code> attribute. This enables debug information to be\ndisplayed in the <a class=\"reference internal\" href=\"#template-postmortem\"><span class=\"std std-ref\">template postmortem</span></a>, as well as\nin 3rd-party libraries, like the <a class=\"extlink-pypi reference external\" href=\"https://pypi.org/project/django-debug-toolbar/\">Django Debug Toolbar</a>.</p>\n<p>Motores personalizados podem prover suas próprias informações de <code class=\"docutils literal notranslate\"><span class=\"pre\">template.origin</span></code> por criar um objeto que especifique os seguintes atributos:</p>\n<ul class=\"simple\">\n<li><p><code class=\"docutils literal notranslate\"><span class=\"pre\">'name'</span></code>: O caminho completo do template.</p></li>\n<li><p><code class=\"docutils literal notranslate\"><span class=\"pre\">'template_name'</span></code>: O caminho relativo do template como foi passado aos mecanismos de carregamento de template.</p></li>\n<li><p><code class=\"docutils literal notranslate\"><span class=\"pre\">'loader_name'</span></code>: Uma string opcional identificando a função ou classe utilizada para carregar o template, por exemplo <code class=\"docutils literal notranslate\"><span class=\"pre\">django.template.loaders.filesystem.Loader</span></code>.</p></li>\n</ul>\n</section>\n</section>","rootId":"how-to-implement-a-custom-template-backend","toc":[{"title":"Backends personalizados","anchor":"custom-backends","children":[]},{"title":"Debugar a integração para motores personalizados","anchor":"debug-integration-for-custom-engines","children":[{"title":"Template postmortem","anchor":"template-postmortem","children":[]},{"title":"Linha de informações contextuais","anchor":"contextual-line-information","children":[]},{"title":"API de Origem e integração com terceiros","anchor":"origin-api-and-3rd-party-integration","children":[]}]}],"breadcrumbs":[{"docname":"howto/index","title":"How-to guides","url":"/pt-br/6.1/howto/"}],"prev":{"docname":"howto/overriding-templates","title":"How to override templates","url":"/pt-br/6.1/howto/overriding-templates/"},"next":{"docname":"howto/custom-template-tags","title":"Como criar tags e filtros de template customizados","url":"/pt-br/6.1/howto/custom-template-tags/"},"formats":{"html":"/pt-br/6.1/howto/custom-template-backend/","markdown":"/pt-br/6.1/howto/custom-template-backend.md","json":"/pt-br/6.1/howto/custom-template-backend.json"},"source":"https://github.com/django/django/blob/stable/6.1.x/docs/howto/custom-template-backend.txt","official":"https://docs.djangoproject.com/pt-br/6.1/howto/custom-template-backend/","inVersions":["6.1","6.0","5.2","5.1","5.0","4.2","4.1","4.0","3.2","3.1"],"inLocales":["en","sv","zh-hans","ga","fr","ja","id","it","pt-br","ko","es","el","pl"]}