Add utils to playlist module to handle xspf file (#836). The clean_namespace_xspf function need to be update to handle the input format of the xspf file when the front-end art will be done.

api/funkwhale_api/playlists/utils.py

@@ -0,0 +1,139 @@
+import logging
+import os
+import re
+
+# /!\ The next import have xml vulnerabilities but this shouldn't have security implication in funkwhale
+# since there are only used to generate xspf file.
+from xml.etree.ElementTree import Element, SubElement
+
+from defusedxml import ElementTree as etree
+from defusedxml import minidom
+
+from funkwhale_api.music.models import Album, Artist, Track
+from funkwhale_api.playlists.models import Playlist
+
+logger = logging.getLogger(__name__)
+
+
+def clean_namespace_xspf(xspf_file):
+    """
+        This will delete any namaespace found in the xspf file. It will also delete any encoding info.
+        This way xspf file will be compatible with our get_playlist_metadata_from_xspf function.
+    """
+    file = open(xspf_file)
+    with file as f:
+        xspf_str = f.read()
+    xspf_data = re.sub('xmlns="http://xspf.org/ns/0/"', "", xspf_str)
+    # This is needed because lxml error : "ValueError: Unicode strings with encoding declaration are
+    # not supported. Please use bytes input or XML fragments without declaration."
+    xspf_data = re.sub("'encoding='.'", "", xspf_data)
+    xspf_file_clean = xspf_file + "2"
+    if os.path.exists(xspf_file_clean):
+        os.remove(xspf_file_clean)
+    file = open(xspf_file_clean, "x")
+    file.write(xspf_data)
+
+    return xspf_file_clean
+
+
+def get_track_id_from_xspf(xspf_file):
+    """
+        Return a list of funkwhale tracks id from a xspf file. Tracks not found in database are ignored.
+    """
+    track_list = []
+    xspf_file_clean = clean_namespace_xspf(xspf_file)
+    tree = etree.parse(xspf_file_clean)
+    tracks = tree.findall(".//track")
+    total_track_count = 0
+    added_file_count = 0
+
+    for track in tracks:
+        track_id = ""
+        total_track_count = total_track_count + 1
+        total = str(total_track_count)
+        # Getting metadata of the xspf file
+        try:
+            artist = track.find(".//creator").text
+        except Exception as e:
+            logger.info("Error while parsing Xml file :%s" % e)
+        try:
+            title = track.find(".//title").text
+        except Exception as e:
+            logger.info("Error while parsing Xml file :%s" % e)
+        try:
+            album = track.find(".//album").text
+        except Exception as e:
+            logger.info("Error while parsing Xml file :%s" % e)
+
+        # Finding track id in the db
+        try:
+            artist_id = Artist.objects.get(name=artist)
+        except Exception as e:
+            logger.info("Error while quering database : %s" % e)
+        try:
+            album_id = Album.objects.get(title=album)
+        except Exception as e:
+            logger.info("Error while quering database :%s" % e)
+        try:
+            track_id = Track.objects.get(
+                title=title, artist=artist_id.id, album=album_id.id
+            )
+        except Exception as e:
+            if e:
+                try:
+                    track_id = Track.objects.get(title=title, artist=artist_id.id)
+                except Exception as e:
+                    logger.info("Error while quering database :%s" % e)
+        if track_id:
+            track_list.append(track_id.id)
+            added_file_count = added_file_count + 1
+
+    logger.info(
+        str(total)
+        + " tracks where found in xspf file. "
+        + str(added_file_count)
+        + "are gonna be added to playlist."
+    )
+    return track_list
+
+
+def generate_xspf_from_playlist(playlist_id):
+    """
+        This returns a string containing playlist data in xspf format
+    """
+    fw_playlist = Playlist.objects.get(id=playlist_id)
+    tracks_id = fw_playlist.playlist_tracks.all().values_list("track_id", flat=True)
+
+    top = Element("playlist")
+    top.set("version", "1")
+    # top.append(Element.fromstring('version="1"'))
+    title_xspf = SubElement(top, "title")
+    title_xspf.text = fw_playlist.name
+    date_xspf = SubElement(top, "date")
+    date_xspf.text = str(fw_playlist.creation_date)
+    trackList_xspf = SubElement(top, "trackList")
+
+    for track_id in tracks_id:
+        track = Track.objects.get(id=track_id)
+        track_xspf = SubElement(trackList_xspf, "track")
+        location_xspf = SubElement(track_xspf, "location")
+        location_xspf.text = "https://" + track.domain_name + track.listen_url
+        title_xspf = SubElement(track_xspf, "title")
+        title_xspf.text = str(track.title)
+        creator_xspf = SubElement(track_xspf, "creator")
+        creator_xspf.text = str(track.artist)
+        if str(track.album) == "[non-album tracks]":
+            continue
+        else:
+            album_xspf = SubElement(track_xspf, "album")
+            album_xspf.text = str(track.album)
+    return prettify(top)
+
+
+def prettify(elem):
+    """
+        Return a pretty-printed XML string for the Element.
+    """
+    rough_string = etree.tostring(elem, "utf-8")
+    reparsed = minidom.parseString(rough_string)
+    return reparsed.toprettyxml(indent="  ")