feedgenerator: atom feed finished (not entries)

feedgenerator.py

@@ -10,7 +10,7 @@
 '''
 
 from lxml import etree
-from email.Utils import formatdate
+from datetime import datetime
 
 
 class FeedGenerator:
@@ -18,30 +18,29 @@ class FeedGenerator:
 	## ATOM
 	# http://www.atomenabled.org/developers/syndication/
 	# required
-	__atom_id = ''
+	__atom_id = None
-	__atom_title = ''
+	__atom_title = None
-	__atom_updated = ''
+	__atom_updated = datetime.utcnow().isoformat('T')+'Z'
 
 	# recommended
-	__atom_author = '' # {name*, uri, email}
+	__atom_author = None # {name*, uri, email}
-	__atom_link = ''
+	__atom_link = None # {href*, rel, type, hreflang, title, length}
 
-	'''
 	# optional
-	category = ''
+	__atom_category = None # {term*, schema, label}
-	contributor = ''
+	__atom_contributor = None
-	generator = ''
+	__atom_generator = {'value':'Lernfunk3 FeedGenerator'} #{value*,uri,version}
-	icon = ''
+	__atom_icon = None
-	logo = ''
+	__atom_logo = None
-	rights = ''
+	__atom_rights = None
-	subtitle = ''
+	__atom_subtitle = None
-
 
 	## RSS
-	title
+	__rss_title = None
-	link
+	__rss_link = None
-	description
+	__rss_description = None
 
+	'''
 	category
 	cloud
 	copyright
@@ -64,8 +63,24 @@ class FeedGenerator:
 	# rss -> channel
 	'''
 
-	def __init__(self):
+
-		self.__atom_updated = formatdate()
+	def __ensure_format(self, val, allowed, required, allowed_values={}):
+		if not val:
+			return None
+		# Make shure that we have a list of dicts. Even if there is only one.
+		if not isinstance(val, list):
+			val = [val]
+		for elem in val:
+			if not isinstance(elem, dict):
+				raise ValueError('Invalid data (value is no dictionary)')
+			if not set(elem.keys()) <= allowed:
+				raise ValueError('Data contains invalid keys')
+			if not set(elem.keys()) >= required:
+				raise ValueError('Data contains not all required keys')
+			for k,v in allowed_values.iteritems():
+				if elem.get(k) and not elem[k] in v:
+					raise ValueError('Invalid value for %s' % k )
+		return val
 
 
 	def atom_str(self):
@@ -81,8 +96,7 @@ class FeedGenerator:
 		updated.text = self.__atom_updated
 
 		# Add author elements
-		if self.__atom_author:
+		for a in self.__atom_author or []:
-			for a in self.__atom_author:
 			# Atom requires a name. Skip elements without.
 			if not a.get('name'):
 				continue
@@ -96,8 +110,7 @@ class FeedGenerator:
 				email = etree.SubElement(author, 'url')
 				email.text = a.get('uri')
 
-		if self.__atom_link:
+		for l in self.__atom_link or []:
-			for l in self.__atom_link:
 			link = etree.SubElement(feed, 'link', href=l['href'])
 			if l.get('rel'):
 				link.attrib['rel'] = l['rel']
@@ -110,6 +123,52 @@ class FeedGenerator:
 			if l.get('length'):
 				link.attrib['length'] = l['length']
 
+		for c in self.__atom_category or []:
+			cat = etree.SubElement(feed, 'category', term=c['term'])
+			if c.get('schema'):
+				cat.attrib['schema'] = c['schema']
+			if c.get('label'):
+				cat.attrib['label'] = c['label']
+
+		# Add author elements
+		for c in self.__atom_contributor or []:
+			# Atom requires a name. Skip elements without.
+			if not c.get('name'):
+				continue
+			contrib = etree.SubElement(feed, 'contributor')
+			name = etree.SubElement(contrib, 'name')
+			name.text = c.get('name')
+			if c.get('email'):
+				email = etree.SubElement(contrib, 'email')
+				email.text = c.get('email')
+			if c.get('uri'):
+				email = etree.SubElement(contrib, 'url')
+				email.text = c.get('uri')
+
+		if self.__atom_generator:
+			generator = etree.SubElement(feed, 'generator')
+			generator.text = self.__atom_generator['value']
+			if self.__atom_generator.get('uri'):
+				generator.attrib['uri'] = self.__atom_generator['uri']
+			if self.__atom_generator.get('version'):
+				generator.attrib['version'] = self.__atom_generator['version']
+
+		if self.__atom_icon:
+			icon = etree.SubElement(feed, 'icon')
+			icon.text = self.__atom_icon
+
+		if self.__atom_logo:
+			logo = etree.SubElement(feed, 'logo')
+			logo.text = self.__atom_logo
+
+		if self.__atom_rights:
+			rights = etree.SubElement(feed, 'rights')
+			rights.text = self.__atom_rights
+
+		if self.__atom_subtitle:
+			subtitle = etree.SubElement(feed, 'subtitle')
+			subtitle.text = self.__atom_subtitle
+
 		return etree.tostring(feed, pretty_print=True)
 		'''
 		outFile = open('homemade.xml', 'w')
@@ -129,7 +188,7 @@ class FeedGenerator:
 		return self.__atom_id
 
 
-	def author(self, author=None, replace=False):
+	def author(self, author=None, replace=False, **kwargs):
 		'''Get or set autor data. An author element is a dict containing a name,
 		an email adress and a uri. Name is mandatory for ATOM, email is mandatory
 		for RSS.
@@ -139,26 +198,28 @@ class FeedGenerator:
 
 		Example::
 
-			>>> author( { 'name'='John Doe', 'email'='jdoe@example.com' } )
+			>>> author( { 'name':'John Doe', 'email':'jdoe@example.com' } )
-			[{'name'='John Doe','email'='jdoe@example.com'}]
+			[{'name':'John Doe','email':'jdoe@example.com'}]
 
-			>>> author([{'name'='John Doe'},{'name'='Max'}])
+			>>> author([{'name':'Mr. X'},{'name':'Max'}])
-			[{'name'='John Doe'},{'name'='Max'}]
+			[{'name':'John Doe','email':'jdoe@example.com'},
+					{'name':'John Doe'}, {'name':'Max'}]
+
+			>>> author( name='John Doe', email='jdoe@example.com', replace=True )
+			[{'name':'John Doe','email':'jdoe@example.com'}]
 
 		'''
+		if author is None and kwargs:
+			author = kwargs
 		if not author is None:
-			if not isinstance(author, list):
+			if replace or self.__atom_author is None:
-				author = [ author ]
+				self.__atom_author = []
-			for a in author:
+			self.__atom_author += self.__ensure_format( author, 
-				if not isinstance(a, dict):
+					set(['name', 'email', 'uri']), set(['name']))
-					raise ValueError('Invalid author data (author is no dict)')
-				if not set(a.keys()) <= set(['name', 'email', 'uri']):
-					raise ValueError('Invalid author data')
-			self.__atom_author = author
 		return self.__atom_author
 
 
-	def link(self, link=None, replace=False):
+	def link(self, link=None, replace=False, **kwargs):
 		'''Get or set link data. An link element is a dict with the fields href,
 		rel, type, hreflang, title, and length. Href is mandatory for ATOM.
 		
@@ -170,23 +231,76 @@ class FeedGenerator:
 			link(...)
 
 		'''
+		if link is None and kwargs:
+			link = kwargs
 		if not link is None:
-			if not isinstance(link, list):
+			if replace or self.__atom_link is None:
-				link = [ link ]
+				self.__atom_link = []
-			for l in link:
+			self.__atom_link += self.__ensure_format( link, 
-				if not isinstance(l, dict):
+					set(['href', 'rel', 'type', 'hreflang', 'title', 'length']),
-					raise ValueError('Invalid link data (link is no dict)')
+					set(['href']), 
-				if not set(l.keys()) <= set(['href', 'rel', 'type', 'hreflang', 'title', 'length']):
+					{'rel':['alternate', 'enclosure', 'related', 'self', 'via']} )
-					raise ValueError('Invalid link data')
-				if not set(l.keys()) >= set(['href']):
-					raise ValueError('Invalid link data (no href)')
-				if l.get('rel') and l['rel'] not in \
-						['alternate', 'enclosure', 'related', 'self', 'via']:
-					raise ValueError('Invalid rel type')
-			self.__atom_link = link
 		return self.__atom_link
 
 
+	def category(self, category=None, replace=False, **kwargs):
+		if category is None and kwargs:
+			category = kwargs
+		if not category is None:
+			if replace or self.__atom_category is None:
+				self.__atom_category = []
+			self.__atom_category += self.__ensure_format( 
+					category, 
+					set(['term', 'schema', 'label']),
+					set(['term']) )
+		return self.__atom_category
+
+
+	def contributor(self, contributor=None, replace=False, **kwargs):
+		if contributor is None and kwargs:
+			contributor = kwargs
+		if not contributor is None:
+			if replace or self.__atom_contributor is None:
+				self.__atom_contributor = []
+			self.__atom_contributor += self.__ensure_format( contributor, 
+					set(['name', 'email', 'uri']), set(['name']))
+		return self.__atom_contributor
+
+
+	def generator(self, generator=None, version=None, uri=None):
+		if not generator is None:
+			self.__atom_generator = {'value':generator}
+			if not version in None:
+				self.__atom_generator['version'] = version
+			if not uri in None:
+				self.__atom_generator['uri'] = uri
+		return self.__atom_generator
+
+
+	def icon(self, icon=None):
+		if not icon is None:
+			self.__atom_icon = icon
+		return self.__atom_icon
+
+
+	def logo(self, logo=None):
+		if not logo is None:
+			self.__atom_logo = logo
+		return self.__atom_logo
+
+
+	def rights(self, rights=None):
+		if not rights is None:
+			self.__atom_rights = rights
+		return self.__atom_rights
+
+
+	def subtitle(self, subtitle=None):
+		if not subtitle is None:
+			self.__atom_subtitle = subtitle
+		return self.__atom_subtitle
+
+
 class FeedEntry:
 
 	'''
@@ -229,8 +343,16 @@ class FeedEntry:
 
 if __name__ == '__main__':
 	fg = FeedGenerator()
-	fg.id('123')
+	fg.id('http://lernfunk.de/_MEDIAID_123')
 	fg.title('Testfeed')
 	fg.author( {'name':'Lars Kiesow','email':'lkiesow@uos.de'} )
-	fg.link( {'href':'http://example.com', 'rel':'alternate'} )
+	fg.link( href='http://example.com', rel='alternate' )
+	fg.category(term='test')
+	fg.contributor( name='Lars Kiesow', email='lkiesow@uos.de' )
+	fg.contributor( name='John Doe', email='jdoe@example.com' )
+	fg.icon('http://ex.com/icon.jpg')
+	fg.logo('http://ex.com/logo.jpg')
+	fg.rights('cc-by')
+	fg.subtitle('This is a cool feed!')
+	fg.link( href='http://larskiesow.de/test.atom', rel='self' )
 	print fg.atom_str()