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Diffstat (limited to 'werkzeug/contrib/atom.py')
| -rw-r--r-- | werkzeug/contrib/atom.py | 343 |
1 files changed, 343 insertions, 0 deletions
diff --git a/werkzeug/contrib/atom.py b/werkzeug/contrib/atom.py new file mode 100644 index 0000000..8a68857 --- /dev/null +++ b/werkzeug/contrib/atom.py @@ -0,0 +1,343 @@ +# -*- coding: utf-8 -*- +""" + werkzeug.contrib.atom + ~~~~~~~~~~~~~~~~~~~~~ + + This module provides a class called :class:`AtomFeed` which can be + used to generate feeds in the Atom syndication format (see :rfc:`4287`). + + Example:: + + def atom_feed(request): + feed = AtomFeed("My Blog", feed_url=request.url, + url=request.host_url, + subtitle="My example blog for a feed test.") + for post in Post.query.limit(10).all(): + feed.add(post.title, post.body, content_type='html', + author=post.author, url=post.url, id=post.uid, + updated=post.last_update, published=post.pub_date) + return feed.get_response() + + :copyright: (c) 2010 by the Werkzeug Team, see AUTHORS for more details. + :license: BSD, see LICENSE for more details. +""" +from datetime import datetime +from werkzeug.utils import escape +from werkzeug.wrappers import BaseResponse + + +XHTML_NAMESPACE = 'http://www.w3.org/1999/xhtml' + + +def _make_text_block(name, content, content_type=None): + """Helper function for the builder that creates an XML text block.""" + if content_type == 'xhtml': + return u'<%s type="xhtml"><div xmlns="%s">%s</div></%s>\n' % \ + (name, XHTML_NAMESPACE, content, name) + if not content_type: + return u'<%s>%s</%s>\n' % (name, escape(content), name) + return u'<%s type="%s">%s</%s>\n' % (name, content_type, + escape(content), name) + + +def format_iso8601(obj): + """Format a datetime object for iso8601""" + return obj.strftime('%Y-%m-%dT%H:%M:%SZ') + + +class AtomFeed(object): + """A helper class that creates Atom feeds. + + :param title: the title of the feed. Required. + :param title_type: the type attribute for the title element. One of + ``'html'``, ``'text'`` or ``'xhtml'``. + :param url: the url for the feed (not the url *of* the feed) + :param id: a globally unique id for the feed. Must be an URI. If + not present the `feed_url` is used, but one of both is + required. + :param updated: the time the feed was modified the last time. Must + be a :class:`datetime.datetime` object. If not + present the latest entry's `updated` is used. + :param feed_url: the URL to the feed. Should be the URL that was + requested. + :param author: the author of the feed. Must be either a string (the + name) or a dict with name (required) and uri or + email (both optional). Can be a list of (may be + mixed, too) strings and dicts, too, if there are + multiple authors. Required if not every entry has an + author element. + :param icon: an icon for the feed. + :param logo: a logo for the feed. + :param rights: copyright information for the feed. + :param rights_type: the type attribute for the rights element. One of + ``'html'``, ``'text'`` or ``'xhtml'``. Default is + ``'text'``. + :param subtitle: a short description of the feed. + :param subtitle_type: the type attribute for the subtitle element. + One of ``'text'``, ``'html'``, ``'text'`` + or ``'xhtml'``. Default is ``'text'``. + :param links: additional links. Must be a list of dictionaries with + href (required) and rel, type, hreflang, title, length + (all optional) + :param generator: the software that generated this feed. This must be + a tuple in the form ``(name, url, version)``. If + you don't want to specify one of them, set the item + to `None`. + :param entries: a list with the entries for the feed. Entries can also + be added later with :meth:`add`. + + For more information on the elements see + http://www.atomenabled.org/developers/syndication/ + + Everywhere where a list is demanded, any iterable can be used. + """ + + default_generator = ('Werkzeug', None, None) + + def __init__(self, title=None, entries=None, **kwargs): + self.title = title + self.title_type = kwargs.get('title_type', 'text') + self.url = kwargs.get('url') + self.feed_url = kwargs.get('feed_url', self.url) + self.id = kwargs.get('id', self.feed_url) + self.updated = kwargs.get('updated') + self.author = kwargs.get('author', ()) + self.icon = kwargs.get('icon') + self.logo = kwargs.get('logo') + self.rights = kwargs.get('rights') + self.rights_type = kwargs.get('rights_type') + self.subtitle = kwargs.get('subtitle') + self.subtitle_type = kwargs.get('subtitle_type', 'text') + self.generator = kwargs.get('generator') + if self.generator is None: + self.generator = self.default_generator + self.links = kwargs.get('links', []) + self.entries = entries and list(entries) or [] + + if not hasattr(self.author, '__iter__') \ + or isinstance(self.author, (basestring, dict)): + self.author = [self.author] + for i, author in enumerate(self.author): + if not isinstance(author, dict): + self.author[i] = {'name': author} + + if not self.title: + raise ValueError('title is required') + if not self.id: + raise ValueError('id is required') + for author in self.author: + if 'name' not in author: + raise TypeError('author must contain at least a name') + + def add(self, *args, **kwargs): + """Add a new entry to the feed. This function can either be called + with a :class:`FeedEntry` or some keyword and positional arguments + that are forwarded to the :class:`FeedEntry` constructor. + """ + if len(args) == 1 and not kwargs and isinstance(args[0], FeedEntry): + self.entries.append(args[0]) + else: + kwargs['feed_url'] = self.feed_url + self.entries.append(FeedEntry(*args, **kwargs)) + + def __repr__(self): + return '<%s %r (%d entries)>' % ( + self.__class__.__name__, + self.title, + len(self.entries) + ) + + def generate(self): + """Return a generator that yields pieces of XML.""" + # atom demands either an author element in every entry or a global one + if not self.author: + if False in map(lambda e: bool(e.author), self.entries): + self.author = ({'name': u'unbekannter Autor'},) + + if not self.updated: + dates = sorted([entry.updated for entry in self.entries]) + self.updated = dates and dates[-1] or datetime.utcnow() + + yield u'<?xml version="1.0" encoding="utf-8"?>\n' + yield u'<feed xmlns="http://www.w3.org/2005/Atom">\n' + yield ' ' + _make_text_block('title', self.title, self.title_type) + yield u' <id>%s</id>\n' % escape(self.id) + yield u' <updated>%s</updated>\n' % format_iso8601(self.updated) + if self.url: + yield u' <link href="%s" />\n' % escape(self.url, True) + if self.feed_url: + yield u' <link href="%s" rel="self" />\n' % \ + escape(self.feed_url, True) + for link in self.links: + yield u' <link %s/>\n' % ''.join('%s="%s" ' % \ + (k, escape(link[k], True)) for k in link) + for author in self.author: + yield u' <author>\n' + yield u' <name>%s</name>\n' % escape(author['name']) + if 'uri' in author: + yield u' <uri>%s</uri>\n' % escape(author['uri']) + if 'email' in author: + yield ' <email>%s</email>\n' % escape(author['email']) + yield ' </author>\n' + if self.subtitle: + yield ' ' + _make_text_block('subtitle', self.subtitle, + self.subtitle_type) + if self.icon: + yield u' <icon>%s</icon>\n' % escape(self.icon) + if self.logo: + yield u' <logo>%s</logo>\n' % escape(self.logo) + if self.rights: + yield ' ' + _make_text_block('rights', self.rights, + self.rights_type) + generator_name, generator_url, generator_version = self.generator + if generator_name or generator_url or generator_version: + tmp = [u' <generator'] + if generator_url: + tmp.append(u' uri="%s"' % escape(generator_url, True)) + if generator_version: + tmp.append(u' version="%s"' % escape(generator_version, True)) + tmp.append(u'>%s</generator>\n' % escape(generator_name)) + yield u''.join(tmp) + for entry in self.entries: + for line in entry.generate(): + yield u' ' + line + yield u'</feed>\n' + + def to_string(self): + """Convert the feed into a string.""" + return u''.join(self.generate()) + + def get_response(self): + """Return a response object for the feed.""" + return BaseResponse(self.to_string(), mimetype='application/atom+xml') + + def __call__(self, environ, start_response): + """Use the class as WSGI response object.""" + return self.get_response()(environ, start_response) + + def __unicode__(self): + return self.to_string() + + def __str__(self): + return self.to_string().encode('utf-8') + + +class FeedEntry(object): + """Represents a single entry in a feed. + + :param title: the title of the entry. Required. + :param title_type: the type attribute for the title element. One of + ``'html'``, ``'text'`` or ``'xhtml'``. + :param content: the content of the entry. + :param content_type: the type attribute for the content element. One + of ``'html'``, ``'text'`` or ``'xhtml'``. + :param summary: a summary of the entry's content. + :param summary_type: the type attribute for the summary element. One + of ``'html'``, ``'text'`` or ``'xhtml'``. + :param url: the url for the entry. + :param id: a globally unique id for the entry. Must be an URI. If + not present the URL is used, but one of both is required. + :param updated: the time the entry was modified the last time. Must + be a :class:`datetime.datetime` object. Required. + :param author: the author of the feed. Must be either a string (the + name) or a dict with name (required) and uri or + email (both optional). Can be a list of (may be + mixed, too) strings and dicts, too, if there are + multiple authors. Required if not every entry has an + author element. + :param published: the time the entry was initially published. Must + be a :class:`datetime.datetime` object. + :param rights: copyright information for the entry. + :param rights_type: the type attribute for the rights element. One of + ``'html'``, ``'text'`` or ``'xhtml'``. Default is + ``'text'``. + :param links: additional links. Must be a list of dictionaries with + href (required) and rel, type, hreflang, title, length + (all optional) + :param xml_base: The xml base (url) for this feed item. If not provided + it will default to the item url. + + For more information on the elements see + http://www.atomenabled.org/developers/syndication/ + + Everywhere where a list is demanded, any iterable can be used. + """ + + def __init__(self, title=None, content=None, feed_url=None, **kwargs): + self.title = title + self.title_type = kwargs.get('title_type', 'text') + self.content = content + self.content_type = kwargs.get('content_type', 'html') + self.url = kwargs.get('url') + self.id = kwargs.get('id', self.url) + self.updated = kwargs.get('updated') + self.summary = kwargs.get('summary') + self.summary_type = kwargs.get('summary_type', 'html') + self.author = kwargs.get('author') + self.published = kwargs.get('published') + self.rights = kwargs.get('rights') + self.links = kwargs.get('links', []) + self.xml_base = kwargs.get('xml_base', feed_url) + + if not hasattr(self.author, '__iter__') \ + or isinstance(self.author, (basestring, dict)): + self.author = [self.author] + for i, author in enumerate(self.author): + if not isinstance(author, dict): + self.author[i] = {'name': author} + + if not self.title: + raise ValueError('title is required') + if not self.id: + raise ValueError('id is required') + if not self.updated: + raise ValueError('updated is required') + + def __repr__(self): + return '<%s %r>' % ( + self.__class__.__name__, + self.title + ) + + def generate(self): + """Yields pieces of ATOM XML.""" + base = '' + if self.xml_base: + base = ' xml:base="%s"' % escape(self.xml_base, True) + yield u'<entry%s>\n' % base + yield u' ' + _make_text_block('title', self.title, self.title_type) + yield u' <id>%s</id>\n' % escape(self.id) + yield u' <updated>%s</updated>\n' % format_iso8601(self.updated) + if self.published: + yield u' <published>%s</published>\n' % \ + format_iso8601(self.published) + if self.url: + yield u' <link href="%s" />\n' % escape(self.url) + for author in self.author: + yield u' <author>\n' + yield u' <name>%s</name>\n' % escape(author['name']) + if 'uri' in author: + yield u' <uri>%s</uri>\n' % escape(author['uri']) + if 'email' in author: + yield u' <email>%s</email>\n' % escape(author['email']) + yield u' </author>\n' + for link in self.links: + yield u' <link %s/>\n' % ''.join('%s="%s" ' % \ + (k, escape(link[k], True)) for k in link) + if self.summary: + yield u' ' + _make_text_block('summary', self.summary, + self.summary_type) + if self.content: + yield u' ' + _make_text_block('content', self.content, + self.content_type) + yield u'</entry>\n' + + def to_string(self): + """Convert the feed item into a unicode object.""" + return u''.join(self.generate()) + + def __unicode__(self): + return self.to_string() + + def __str__(self): + return self.to_string().encode('utf-8') |