Metadata-Version: 2.1 Name: premailer Version: 3.10.0 Summary: Turns CSS blocks into style attributes Home-page: http://github.com/peterbe/premailer Author: Peter Bengtsson Author-email: mail@peterbe.com License: Python Keywords: html lxml email mail style Platform: UNKNOWN Classifier: Development Status :: 5 - Production/Stable Classifier: Environment :: Other Environment Classifier: Environment :: Web Environment Classifier: Intended Audience :: Developers Classifier: License :: OSI Approved :: Python Software Foundation License Classifier: Operating System :: OS Independent Classifier: Programming Language :: Python Classifier: Programming Language :: Python :: 3 Classifier: Programming Language :: Python :: 3.5 Classifier: Programming Language :: Python :: 3.6 Classifier: Programming Language :: Python :: 3.7 Classifier: Programming Language :: Python :: 3.8 Classifier: Programming Language :: Python :: Implementation :: CPython Classifier: Programming Language :: Python :: Implementation :: PyPy Classifier: Topic :: Communications Classifier: Topic :: Internet :: WWW/HTTP Classifier: Topic :: Other/Nonlisted Topic Classifier: Topic :: Software Development :: Libraries :: Python Modules Requires-Dist: lxml Requires-Dist: cssselect Requires-Dist: cssutils Requires-Dist: requests Requires-Dist: cachetools Provides-Extra: dev Requires-Dist: tox ; extra == 'dev' Requires-Dist: twine ; extra == 'dev' Requires-Dist: therapist ; extra == 'dev' Requires-Dist: black ; extra == 'dev' Requires-Dist: flake8 ; extra == 'dev' Requires-Dist: wheel ; extra == 'dev' Provides-Extra: test Requires-Dist: nose ; extra == 'test' Requires-Dist: mock ; extra == 'test' premailer ========= .. image:: https://travis-ci.org/peterbe/premailer.svg?branch=master :target: https://travis-ci.org/peterbe/premailer .. image:: https://badge.fury.io/py/premailer.svg :target: https://pypi.python.org/pypi/premailer .. image:: https://img.shields.io/badge/code%20style-black-000000.svg :target: https://github.com/ambv/black Looking for sponsors -------------------- This project is actively looking for corporate sponsorship. If you want to help making this an active project consider `pinging Peter `__ and we can talk about putting up logos and links to your company. Python versions --------------- Our `tox.ini `__ makes sure premailer works in: - Python 3.4 - Python 3.5 - Python 3.6 - Python 3.7 - Python 3.8 - PyPy Turns CSS blocks into style attributes -------------------------------------- When you send HTML emails you can't use style tags but instead you have to put inline ``style`` attributes on every element. So from this: .. code:: html

Peter

Hej

You want this: .. code:: html

Peter

Hej

premailer does this. It parses an HTML page, looks up ``style`` blocks and parses the CSS. It then uses the ``lxml.html`` parser to modify the DOM tree of the page accordingly. Warning! By default, premailer will attempt to download any external stylesheets by URL over the Internet. If you want to prevent this you can use the ``allow_network=False`` option. Getting started --------------- If you haven't already done so, install ``premailer`` first: :: $ pip install premailer Next, the most basic use is to use the shortcut function, like this: .. code:: python >>> from premailer import transform >>> print(transform(""" ... ... ... ...

Peter

...

Hej

... ... """))

Peter

Hej

The ``transform`` shortcut function transforms the given HTML using the defaults for all options: .. code:: python base_url=None, # Optional URL prepended to all relative links (both stylesheets and internal) disable_link_rewrites=False, # Allow link rewrites (e.g. using base_url) preserve_internal_links=False, # Do not preserve links to named anchors when using base_url preserve_inline_attachments=True, # Preserve links with cid: scheme when base_url is specified preserve_handlebar_syntax=False # Preserve handlebar syntax from being encoded exclude_pseudoclasses=True, # Ignore pseudoclasses when processing styles keep_style_tags=False, # Discard original style tag include_star_selectors=False, # Ignore star selectors when processing styles remove_classes=False, # Leave class attributes on HTML elements capitalize_float_margin=False, # Do not capitalize float and margin properties strip_important=True, # Remove !important from property values external_styles=None, # Optional list of URLs to load and parse css_text=None, # Optional CSS text to parse method="html", # Parse input as HTML (as opposed to "xml") base_path=None, # Optional base path to stylesheet in your file system disable_basic_attributes=None, # Optional list of attribute names to preserve on HTML elements disable_validation=False, # Validate CSS when parsing it with cssutils cache_css_parsing=True, # Do cache parsed output for CSS cssutils_logging_handler=None, # See "Capturing logging from cssutils" below cssutils_logging_level=None, disable_leftover_css=False, # Output CSS that was not inlined into the HEAD align_floating_images=True, # Add align attribute for floated images remove_unset_properties=True # Remove CSS properties if their value is unset when merged allow_network=True # allow network access to fetch linked css files allow_insecure_ssl=False # Don't allow unverified SSL certificates for external links allow_loading_external_files=False # Allow loading any non-HTTP external file URL session=None # Session used for http requests - supply your own for caching or to provide authentication For more advanced options, check out the code of the ``Premailer`` class and all its options in its constructor. You can also use premailer from the command line by using its main module. :: $ python -m premailer -h usage: python -m premailer [options] optional arguments: -h, --help show this help message and exit -f [INFILE], --file [INFILE] Specifies the input file. The default is stdin. -o [OUTFILE], --output [OUTFILE] Specifies the output file. The default is stdout. --base-url BASE_URL --remove-internal-links PRESERVE_INTERNAL_LINKS Remove links that start with a '#' like anchors. --exclude-pseudoclasses Pseudo classes like p:last-child', p:first-child, etc --preserve-style-tags Do not delete tags from the html document. --remove-star-selectors All wildcard selectors like '* {color: black}' will be removed. --remove-classes Remove all class attributes from all elements --strip-important Remove '!important' for all css declarations. --method METHOD The type of html to output. 'html' for HTML, 'xml' for XHTML. --base-path BASE_PATH The base path for all external stylsheets. --external-style EXTERNAL_STYLES The path to an external stylesheet to be loaded. --disable-basic-attributes DISABLE_BASIC_ATTRIBUTES Disable provided basic attributes (comma separated) --disable-validation Disable CSSParser validation of attributes and values --pretty Pretty-print the outputted HTML. --allow-insecure-ssl Skip SSL certificate verification for external URLs. --allow-loading-external-files Allow opening any non-HTTP external file URL. A basic example: :: $ python -m premailer --base-url=http://google.com/ -f newsletter.html

Title

The command line interface supports standard input. :: $ echo '

Title

' | python -m premailer --base-url=http://google.com/

Title

Turning relative URLs into absolute URLs ---------------------------------------- Another thing premailer can do for you is to turn relative URLs (e.g. "/some/page.html" into "http://www.peterbe.com/some/page.html"). It does this to all ``href`` and ``src`` attributes that don't have a ``://`` part in it. For example, turning this: .. code:: html Home Page External

Folder Into this: .. code:: html Home Page External

Folder by using ``transform('...', base_url='http://www.peterbe.com/')``. Ignore certain `` That tag gets completely ignored except when the HTML is processed, the attribute ``data-premailer`` is removed. It works equally for a ```` tag like: .. code:: html HTML attributes created additionally ------------------------------------ Certain HTML attributes are also created on the HTML if the CSS contains any ones that are easily translated into HTML attributes. For example, if you have this CSS: ``td { background-color:#eee; }`` then this is transformed into ``style="background-color:#eee"`` and as an HTML attribute ``bgcolor="#eee"``. Having these extra attributes basically as a "back up" for really shit email clients that can't even take the style attributes. A lot of professional HTML newsletters such as Amazon's use this. You can disable some attributes in ``disable_basic_attributes``. Capturing logging from ``cssutils`` ----------------------------------- `cssutils `__ is the library that ``premailer`` uses to parse CSS. It will use the python ``logging`` module to mention all issues it has with parsing your CSS. If you want to capture this, you have to pass in ``cssutils_logging_handler`` and ``cssutils_logging_level`` (optional). For example like this: .. code:: python >>> import logging >>> import premailer >>> from io import StringIO >>> mylog = StringIO() >>> myhandler = logging.StreamHandler(mylog) >>> p = premailer.Premailer( ... cssutils_logging_handler=myhandler, ... cssutils_logging_level=logging.INFO ... ) >>> result = p.transform(""" ... ... ...

Hej

... ... """) >>> mylog.getvalue() 'CSSStylesheet: Unknown @rule found. [2:1: @keyframes]\n' If execution speed is on your mind ---------------------------------- If execution speed is important, it's very plausible that you're not just converting 1 HTML document but *a lot* of HTML documents. Then, the first thing you should do is avoid using the ``premailer.transform`` function because it creates a ``Premailer`` class instance every time. .. code:: python # WRONG WAY! from premailer import transform for html_string in get_html_documents(): transformed = transform(html_string, base_url=MY_BASE_URL) # do something with 'transformed' Instead... .. code:: python # RIGHT WAY from premailer import Premailer instance = Premailer(base_url=MY_BASE_URL) for html_string in get_html_documents(): transformed = instance.transform(html_string) # do something with 'transformed' Another thing to watch out for when you're reusing the same imported Python code and reusing it is that internal memoize function caches might build up. The environment variable to control is ``PREMAILER_CACHE_MAXSIZE``. This parameter requires a little bit of fine-tuning and calibration if your workload is really big and memory even becomes an issue. Advanced options ---------------- Below are some advanced configuration options that probably doesn't matter for most people with regular load. Choosing the cache implementation ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ By default, ``premailer`` uses `LFUCache `__ to cache selectors, styles and parsed CSS strings. If LFU doesn't serve your purpose, it is possible to switch to an alternate implementation using below environment variables. - ``PREMAILER_CACHE``: Can be LRU, LFU or TTL. Default is LFU. - ``PREMAILER_CACHE_MAXSIZE``: Maximum no. of items to be stored in cache. Defaults to 128. - ``PREMAILER_CACHE_TTL``: Time to live for cache entries. Only applicable for TTL cache. Defaults to 1 hour. Getting coding -------------- First clone the code and create whatever virtualenv you need, then run: .. code:: bash pip install -e ".[dev]" Then to run the tests, run: .. code:: bash tox This will run the *whole test suite* for every possible version of Python it can find on your system. To run the tests more incrementally, open up the ``tox.ini`` and see how it works. Code style is all black ----------------------- All code has to be formatted with `Black `_ and the best tool for checking this is `therapist `_ since it can help you run all, help you fix things, and help you make sure linting is passing before you git commit. This project also uses ``flake8`` to check other things Black can't check. To check linting with ``tox`` use: .. code:: bash tox -e lint To install the ``therapist`` pre-commit hook simply run: .. code:: bash therapist install When you run ``therapist run`` it will only check the files you've touched. To run it for all files use: .. code:: bash therapist run --use-tracked-files And to fix all/any issues run: .. code:: bash therapist run --use-tracked-files --fix