renamed django app folder to backend

backend/common/src/urlparser.py

@@ -0,0 +1,138 @@
+"""
+Functionality:
+- detect valid youtube ids and links from multi line string
+- identify vid_type if possible
+"""
+
+from urllib.parse import parse_qs, urlparse
+
+from download.src.yt_dlp_base import YtWrap
+from video.src.constants import VideoTypeEnum
+
+
+class Parser:
+    """take a multi line string and detect valid youtube ids"""
+
+    def __init__(self, url_str):
+        self.url_list = [i.strip() for i in url_str.split()]
+
+    def parse(self):
+        """parse the list"""
+        ids = []
+        for url in self.url_list:
+            parsed = urlparse(url)
+            if parsed.netloc:
+                # is url
+                identified = self.process_url(parsed)
+            else:
+                # is not url
+                identified = self._find_valid_id(url)
+
+            if "vid_type" not in identified:
+                identified.update(self._detect_vid_type(parsed.path))
+
+            ids.append(identified)
+
+        return ids
+
+    def process_url(self, parsed):
+        """process as url"""
+        if parsed.netloc == "youtu.be":
+            # shortened
+            youtube_id = parsed.path.strip("/")
+            return self._validate_expected(youtube_id, "video")
+
+        if "youtube.com" not in parsed.netloc:
+            message = f"invalid domain: {parsed.netloc}"
+            raise ValueError(message)
+
+        query_parsed = parse_qs(parsed.query)
+        if "v" in query_parsed:
+            # video from v query str
+            youtube_id = query_parsed["v"][0]
+            return self._validate_expected(youtube_id, "video")
+
+        if "list" in query_parsed:
+            # playlist from list query str
+            youtube_id = query_parsed["list"][0]
+            return self._validate_expected(youtube_id, "playlist")
+
+        all_paths = parsed.path.strip("/").split("/")
+        if all_paths[0] == "shorts":
+            # is shorts video
+            item = self._validate_expected(all_paths[1], "video")
+            item.update({"vid_type": VideoTypeEnum.SHORTS.value})
+            return item
+
+        if all_paths[0] == "channel":
+            return self._validate_expected(all_paths[1], "channel")
+
+        # detect channel
+        channel_id = self._extract_channel_name(parsed.geturl())
+        return {"type": "channel", "url": channel_id}
+
+    def _validate_expected(self, youtube_id, expected_type):
+        """raise value error if not matching"""
+        matched = self._find_valid_id(youtube_id)
+        if matched["type"] != expected_type:
+            raise ValueError(
+                f"{youtube_id} not of expected type {expected_type}"
+            )
+
+        return {"type": expected_type, "url": youtube_id}
+
+    def _find_valid_id(self, id_str):
+        """detect valid id from length of string"""
+        if id_str in ("LL", "WL"):
+            return {"type": "playlist", "url": id_str}
+
+        if id_str.startswith("@"):
+            url = f"https://www.youtube.com/{id_str}"
+            channel_id = self._extract_channel_name(url)
+            return {"type": "channel", "url": channel_id}
+
+        len_id_str = len(id_str)
+        if len_id_str == 11:
+            item_type = "video"
+        elif len_id_str == 24:
+            item_type = "channel"
+        elif len_id_str in (34, 26, 18) or id_str.startswith("TA_playlist_"):
+            item_type = "playlist"
+        else:
+            raise ValueError(f"not a valid id_str: {id_str}")
+
+        return {"type": item_type, "url": id_str}
+
+    @staticmethod
+    def _extract_channel_name(url):
+        """find channel id from channel name with yt-dlp help"""
+        obs_request = {
+            "check_formats": None,
+            "skip_download": True,
+            "extract_flat": True,
+            "playlistend": 0,
+        }
+        url_info = YtWrap(obs_request).extract(url)
+        channel_id = url_info.get("channel_id", False)
+        if channel_id:
+            return channel_id
+
+        url = url_info.get("url", False)
+        if url:
+            # handle old channel name redirect with url path split
+            channel_id = urlparse(url).path.strip("/").split("/")[1]
+
+            return channel_id
+
+        print(f"failed to extract channel id from {url}")
+        raise ValueError
+
+    def _detect_vid_type(self, path):
+        """try to match enum from path, needs to be serializable"""
+        last = path.strip("/").split("/")[-1]
+        try:
+            vid_type = VideoTypeEnum(last).value
+        except ValueError:
+            vid_type = VideoTypeEnum.UNKNOWN.value
+
+        return {"vid_type": vid_type}