https://github.com/pcarbonn/fast_html

Generate HTML conveniently and efficiently in Python
https://github.com/pcarbonn/fast_html

Last synced: 4 months ago
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Generate HTML conveniently and efficiently in Python

• Host: GitHub
• URL: https://github.com/pcarbonn/fast_html
• Owner: pcarbonn
• License: lgpl-3.0
• Created: 2022-09-24T13:49:36.000Z (over 2 years ago)
• Default Branch: main
• Last Pushed: 2024-09-20T09:45:36.000Z (4 months ago)
• Last Synced: 2024-09-20T10:08:59.200Z (4 months ago)
• Language: Python
• Size: 60.5 KB
• Stars: 74
• Watchers: 8
• Forks: 4
• Open Issues: 1
• Metadata Files:
  • Readme: README.md
  • Changelog: CHANGELOG.md
  • License: LICENSE

Awesome Lists containing this project

• awesome-python-html - pcarbonn/fast_html
• awesome-python-html - pcarbonn/fast_html

README

        
**fast_html** is a fast, minimalist HTML generator.

It is an alternative to templating engines, like Jinja,

for use with, e.g., [htmx](https://htmx.org/).

**Pros:**

- use familiar python syntax

- use efficient concatenation techniques

- optional automatic indentation

Unlike other HTML generators (e.g. [Dominate](https://pypi.org/project/dominate/)) that use python objects to represent HTML snippets,

fast_html represents HTML snippets using string [generators](https://docs.python.org/3/glossary.html#term-generator)

that can be rendered extremely fast using `join`.

(see [here](https://python.plainenglish.io/concatenating-strings-efficiently-in-python-9bfc8e8d6f6e))

**Like other HTML generators, one needs to remember:**

- the name of some tags and attributes is changed (e.g., `class_` instead of `class`, due to Python parser)

- there may be conflicts of function names with your code base

Installation

============

`pip install fast_html` or copy the (single) source file in your project.

Don't forget to `add a star on GitHub `_ ! Thanks.

Tutorial:

=========

    >>> from fast_html import *

A tag is created by calling a function of the corresponding name,

and rendered using `render`:

    >>> print(render(p("text")))

    
text


Tag attributes are specified using named arguments:

    >>> print(render(br(id=1)))

    


    >>> print(render(br(id=None)))

    


    >>> print(render(ul(li("text", selected=True))))

    
text


    >>> print(render(ul(li("text", selected=False))))

    
text


The python parser introduces some constraints:

- The following tags require a trailing underscore: `del_`, `input_`, `map_`, `object_`.

- The following tag attributes require a trailing underscore: `class_`, `for_`.

In fact, the trailing underscore in attribute names is always removed by fast_html,

and other underscores are replaced by `-`.

For example, the htmx attribute `hx-get` is set using `hx_get="url"`.

    >>> print(render(object_("text", class_="s12", hx_get="url")))

    text

    >>> print(render(button("Click me", hx_post="/clicked", hx_swap="outerHTML")))

    Click me

The innerHTML can be a list:

    >>> print(render(div(["text", span("item 1"), span("item 2")])))

    
textitem 1item 2



The innerHTML can also be a list of lists:

    >>> print(render(div(["text", [span(f"item {i}") for i in [1,2]]])))

    
textitem 1item 2



    >>> print(render([br(), br()]))

    



The innerHTML can also be specified using the `i` parameter,

after the other attributes, to match the order of rendering:

    >>> print(render(ul(class_="s12", i=[

    ...                 li("item 1"),

    ...                 li("item 2")]

    ...      )))

    


item 1

item 2



You can create your own tag using the `tag` function:

    >>> def my_tag(inner=None, **kwargs):

    ...     yield from tag("my_tag", inner, **kwargs)

    >>> print(render(my_tag("text")))

    text

Options:

========

By default, the inner string of a tag is not escaped:

characters `&`, `<` and `>` in it are not converted to HTML-safe sequences.

    >>> print(render(p("text")))

    
text


Of course, you can escape strings before calling fast_html:

    >>> from html import escape

    >>> print(render(p(escape("text"))))

    
<bold>text</bold>


If your policy is to escape every inner string,

you can activate escaping by setting the variable `escape` to `True`

(or by calling `escape_it(True)`).

    >>> escape_it(True)

    >>> print(render(p("text")))

    
<bold>text</bold>


When debugging your code, you can set global variable `indent` to `True`

(or call `indent_it(True)`) to obtain HTML with tag indentation, e.g.,

    >>> indent_it(True)

    >>> print(render(div(class_="s12", i=["text\n", span("item 1"), span("item 2")])))

    


      text

      

        item 1

      

      

        item 2

      

    

    


You can also convert an HTML string to a function-based code representation:

    >>> print(html_to_code('
Some text
'))

    [div([p(['Some text'], )], class_="example")]