Move rss code to a package

5 files changed, 184 insertions, 0 deletions

diff --git a/rss/__init__.py b/rss/__init__.py
new file mode 100644
index 00000000..c5d54da5
--- /dev/null
+++ b/rss/__init__.py
@@ -0,0 +1,4 @@
+from rss.atom_feed import AtomFeed
+from rss.atom_entry import AtomEntry
+from rss.rss_feed import RssFeed
+from rss.rss_item import RssItem
diff --git a/rss/atom_entry.py b/rss/atom_entry.py
new file mode 100644
index 00000000..4b6e116a
--- /dev/null
+++ b/rss/atom_entry.py
@@ -0,0 +1,39 @@
+#!/usr/bin/env python3
+
+import lxml.etree as ET
+
+class AtomEntry(object):
+    """Class for storing atom:entry data and metadata."""
+
+    # pylint: disable=invalid-name,too-many-instance-attributes
+
+    def __init__(self):
+        """Define available attributes."""
+        self.author = None  # atom:author
+        self.id_text = None  # atom:id, just use URI
+        self.id = None  # atom:id
+        self.relpath = None  # HTML page path relative to home
+        self.link = None  # atom:link
+        self.title_text = None  # plain text title
+        self.title = None  # atom:title
+        self.updated_datetime = None  # update time as a datetime object
+        self.updated = None  # atom:updated
+        self.content_html = None  # content as HTML markup
+        self.content = None  # atom:content
+        self.entry = None  # atom:entry, assembled
+
+    def assemble_entry(self):
+        """Assemble atom:entry."""
+        self.entry = ET.Element("entry")
+        self.entry.append(self.title)
+        self.entry.append(self.link)
+        self.entry.append(self.updated)
+        self.entry.append(self.id)
+        self.entry.append(self.author)
+        self.entry.append(self.content)
+
+    def dump_entry(self):
+        """Dump atom:entry XML."""
+        if self.entry is None:
+            self.assemble_entry()
+        return ET.tostring(self.entry).decode("utf-8")
diff --git a/rss/atom_feed.py b/rss/atom_feed.py
new file mode 100644
index 00000000..622ecc08
--- /dev/null
+++ b/rss/atom_feed.py
@@ -0,0 +1,54 @@
+#!/usr/bin/env python3
+
+import lxml.etree as ET
+
+class AtomFeed(object):
+    """Class for storing atom:feed data and metadata.
+
+    https://tools.ietf.org/html/rfc4287.
+
+    """
+
+    # pylint: disable=invalid-name,too-many-instance-attributes
+
+    def __init__(self):
+        """Define available attributes."""
+        self.author = None  # atom:author
+        self.generator = None  # atom:generator, optional
+        self.icon = None  # atom:icon, optional
+        self.logo = None  # atom:logo, optional
+        self.id_text = None  # atom:id, just use URI
+        self.id = None  # atom:id
+        self.links = []  # list of atom:link
+        self.title_text = None  # the text of atom:title
+        self.title = None  # atom:title
+        self.subtitle_text = None  # the text of atom:subtitle
+        self.subtitle = None  # atom:subtitle
+        self.updated_datetime = None  # update time as a datetime object
+        self.updated = None  # atom:updated
+        self.entries = []  # list of atom:entry, in reverse time order
+        self.feed = None  # atom:feed, assembled
+
+    def assemble_feed(self, FEED_MAX_ENTRIES):
+        """Assemble atom:feed."""
+        # pylint: disable=multiple-statements
+        self.feed = ET.Element("feed", xmlns="http://www.w3.org/2005/Atom")
+        self.feed.append(self.title)
+        if self.subtitle is not None: self.feed.append(self.subtitle)
+        for link in self.links:
+            self.feed.append(link)
+        self.feed.append(self.updated)
+        self.feed.append(self.id)
+        self.feed.append(self.author)
+        if self.icon is not None: self.feed.append(self.icon)
+        if self.logo is not None: self.feed.append(self.icon)
+        if self.generator is not None: self.feed.append(self.generator)
+        # include at most FEED_MAX_ENTRIES entries in the feed
+        for entry in self.entries[:FEED_MAX_ENTRIES]:
+            self.feed.append(entry.entry)
+
+    def dump_feed(self, FEED_MAX_ENTRIES):
+        """Dump atom:feed XML."""
+        if self.feed is None:
+            self.assemble_feed(FEED_MAX_ENTRIES)
+        return ET.tostring(self.feed).decode("utf-8")
diff --git a/rss/rss_feed.py b/rss/rss_feed.py
new file mode 100644
index 00000000..5ed6226d
--- /dev/null
+++ b/rss/rss_feed.py
@@ -0,0 +1,57 @@
+#!/usr/bin/env python3
+
+import lxml.etree as ET
+
+class RssFeed(object):
+    """Class for storing an RSS 2.0 feed.
+
+    https://validator.w3.org/feed/docs/rss2.html.
+
+    """
+
+    # pylint: disable=too-many-instance-attributes
+
+    REQUIRED_ELEMENTS = ["title", "link", "description"]
+    OPTIONAL_ELEMENTS = ["language", "copyright", "managingEditor", "webMaster",
+                         "pubDate", "lastBuildDate", "category", "generator",
+                         "docs", "cloud", "ttl", "image", "textInput",
+                         "skipHours", "skipDays"]
+
+    def __init__(self):
+        """Define available attributes."""
+        self.rssurl = None  # the URL of the rss feed
+        self.atomlink = None
+        for element in self.REQUIRED_ELEMENTS:
+            setattr(self, element, None)
+        for element in self.OPTIONAL_ELEMENTS:
+            setattr(self, element, None)
+        self.docs = ET.Element("docs")
+        self.docs.text = "https://validator.w3.org/feed/docs/rss2.html"
+        self.author_text = None
+        self.update_timestamp = None
+        self.items = []
+        self.rss = None
+        self.channel = None
+
+    def assemble_rss(self, FEED_MAX_ENTRIES):
+        """Assemble RSS 2.0 feed."""
+        self.rss = ET.Element("rss", version="2.0", nsmap={"atom": "http://www.w3.org/2005/Atom"})
+        self.channel = ET.SubElement(self.rss, "channel")
+        # https://validator.w3.org/feed/docs/warning/MissingAtomSelfLink.html
+        self.atomlink = ET.SubElement(self.channel, "{http://www.w3.org/2005/Atom}link",
+                                      href=self.rssurl, rel="self", type="application/rss+xml")
+        for element in self.REQUIRED_ELEMENTS:
+            self.channel.append(getattr(self, element))
+        for element in self.OPTIONAL_ELEMENTS:
+            attr = getattr(self, element)
+            if attr is not None:
+                self.channel.append(attr)
+        # include at most FEED_MAX_ENTRIES items in the RSS feed
+        for item in self.items[:FEED_MAX_ENTRIES]:
+            self.channel.append(item.item)
+
+    def dump_rss(self, FEED_MAX_ENTRIES):
+        """Dump RSS feed XML."""
+        if self.rss is None:
+            self.assemble_rss(FEED_MAX_ENTRIES)
+        return ET.tostring(self.rss).decode("utf-8")
diff --git a/rss/rss_item.py b/rss/rss_item.py
new file mode 100644
index 00000000..8ead20e6
--- /dev/null
+++ b/rss/rss_item.py
@@ -0,0 +1,30 @@
+#!/usr/bin/env python3
+
+import lxml.etree as ET
+
+class RssItem(object):
+    """Class for storing an RSS 2.0 item."""
+
+    ELEMENTS = ["title", "link", "description", "author", "category", "comments",
+                "enclosure", "guid", "pubDate", "source"]
+
+    def __init__(self):
+        """Define available attributes."""
+        for element in self.ELEMENTS:
+            setattr(self, element, None)
+        self.timestamp = None
+        self.item = None
+
+    def assemble_item(self):
+        """Assemble an RSS 2.0 item."""
+        self.item = ET.Element("item")
+        for element in self.ELEMENTS:
+            attr = getattr(self, element)
+            if attr is not None:
+                self.item.append(attr)
+
+    def dump_item(self):
+        """Dump RSS item XML."""
+        if self.item is None:
+            self.assemble_item()
+        return ET.tostring(self.item).decode("utf-8")