From ea87e3aab90b44c692c400893507bacb74f11fae Mon Sep 17 00:00:00 2001
From: Marian Steinbach <marian@giantswarm.io>
Date: Mon, 5 Mar 2018 22:28:37 +0100
Subject: [PATCH] Add feed endpoint

---
 service/README.md          | 28 ++++++++++++++++++++++++
 service/api/feeds.py       | 45 ++++++++++++++++++++++++++++++++++++++
 service/api/main.py        | 13 +++++++++++
 service/requirements.txt   |  1 +
 service/tests/test_main.py |  7 ++++++
 5 files changed, 94 insertions(+)
 create mode 100644 service/api/feeds.py

diff --git a/service/README.md b/service/README.md
index 53db6bc..4e90d97 100644
--- a/service/README.md
+++ b/service/README.md
@@ -12,6 +12,34 @@ Kalender zurück.
 
 ## API
 
+### `GET /feed/` - Beiträge eines RSS- oder Atom Feed ausgeben
+
+Request URL Parameter:
+
+- `url`: URL des Feed
+- `num`: Anzahl der Einträge, die zurück gegeben werden sollen (default: 1)
+
+Ausgabe:
+
+```json
+{
+  "meta": {
+    "title": "Die Grünen Rösrath",
+    "link": "http://gruene-roesrath.de",
+    "description": "",
+    "published": null
+  },
+  "items": [
+    {
+      "title": "Informationsveranstaltung zur Start-/Landebahnsanierung am Flughafen",
+      "summary": "Die Flughafen Köln/Bonn GmbH informiert am 1. März über die anstehende Sanierung der großen Start-...",
+      "link": "http://gruene-roesrath.de/startseite/news-detailansicht/article/informationsveranstaltung_zur_start_landebahnsanierung_am_flughafen/",
+      "published": "2018-02-19T20:15:00"
+    }
+  ]
+}
+```
+
 ### `GET /events/` - Die nächsten Termine eines iCal Kalenders ausgeben
 
 Request URL Parameter:
diff --git a/service/api/feeds.py b/service/api/feeds.py
new file mode 100644
index 0000000..4a6c4e0
--- /dev/null
+++ b/service/api/feeds.py
@@ -0,0 +1,45 @@
+import feedparser
+from datetime import datetime
+
+class Client(object):
+
+    def __init__(self, url):
+        self.url = url
+        self.__load()
+
+    def __load(self):
+        self.feed = feedparser.parse(self.url)
+
+    def metadata(self):
+        """
+        Returns meta information from the feed
+        """
+        return {
+            "title": self.feed["feed"].get("title"),
+            "link": self.feed["feed"].get("link"),
+            "description": self.feed["feed"].get("description"),
+            "published": self.feed["feed"].get("published"),
+        }
+
+    def __entry_details(self, entry):
+        """
+        Returns only a few entry details we care about
+        """
+        return {
+            "title": entry["title"],
+            "summary": entry["summary"],
+            "link": entry["link"],
+            "published": datetime(
+                entry["published_parsed"][0], entry["published_parsed"][1], entry["published_parsed"][2],
+                entry["published_parsed"][3], entry["published_parsed"][4], entry["published_parsed"][5]
+            )
+        }
+
+    def recent_items(self, num=3):
+        """
+        Returns the num most recent entries from the feed
+        """
+        out = []
+        for n in range(0, num):
+            out.append(self.__entry_details(self.feed.entries[n]))
+        return out
diff --git a/service/api/main.py b/service/api/main.py
index 9f83eea..bce3980 100644
--- a/service/api/main.py
+++ b/service/api/main.py
@@ -2,6 +2,7 @@
 
 from . import events
 from . import jsonhandler
+from . import feeds
 from datetime import datetime
 from falcon import media
 from falcon_cors import CORS
@@ -31,6 +32,17 @@ class EventsResource(object):
         maxage = 60 * 60  # 1 hour
         resp.cache_control = ["max_age=%d" % maxage]
 
+class FeedResource(object):
+
+    def on_get(self, req, resp):
+        feed_url = req.get_param("url", required=True)
+        num = int(req.get_param("num", required=False, default="1"))
+        c = feeds.Client(feed_url)
+        resp.media = {
+            "meta": c.metadata(),
+            "items": c.recent_items(num=num)
+        }
+
 class ParticleSensorResource(object):
 
     def on_get(self, req, resp, sensor_id):
@@ -61,4 +73,5 @@ app.req_options.media_handlers = handlers
 app.resp_options.media_handlers = handlers
 
 app.add_route('/events/', EventsResource())
+app.add_route('/feed/', FeedResource())
 app.add_route('/luftdaten.info/v1/sensor/{sensor_id}/', ParticleSensorResource())
diff --git a/service/requirements.txt b/service/requirements.txt
index 423b056..389fe02 100644
--- a/service/requirements.txt
+++ b/service/requirements.txt
@@ -3,6 +3,7 @@ certifi==2018.1.18
 chardet==3.0.4
 falcon==1.4.1
 falcon-cors==1.1.7
+feedparser==5.2.1
 funcsigs==1.0.2
 gunicorn==19.7.1
 icalendar==4.0.0
diff --git a/service/tests/test_main.py b/service/tests/test_main.py
index d82174e..6912224 100644
--- a/service/tests/test_main.py
+++ b/service/tests/test_main.py
@@ -21,3 +21,10 @@ def test_get_events(client):
         "ical_url": "http://www.webcal.fi/cal.php?id=75&rid=ics&wrn=0&wp=12&wf=55"
     })
     assert response.status == falcon.HTTP_OK
+
+def test_get_feed(client):
+    response = client.simulate_get('/feed/', params={
+        "url": "http://www.feedforall.com/sample.xml",
+        "num": "1"
+    })
+    assert response.status == falcon.HTTP_OK