Handle unavailable downloading url (#97)

Author: zoubenjia

baidupcs_py/baidupcs/pcs.py

@@ -4,6 +4,7 @@
 
 from pathlib import Path
 from urllib.parse import urlparse, quote_plus
+from urllib.error import URLError, HTTPError
 from base64 import standard_b64encode
 import re
 import json
@@ -986,25 +987,29 @@ def download_link(self, remotepath: str, pcs: bool = False) -> Optional[str]:
             headers = dict(PCS_HEADERS)
             headers["Cookie"] = "; ".join([f"{k}={v}" for k, v in self.cookies.items()])
             req = urllib.request.Request(url + "?" + params_str, headers=headers, method="GET")  # type: ignore
-            resp = urllib.request.urlopen(req)  # type: ignore
-
-            # Error: "user is not authorized"
-            # This error occurs when the method is called by too many times
-            if resp.status != 200:
-                time.sleep(2)
-                continue
-
-            info = json.loads(resp.read())
-
-            # This error is gotten when remote path is blocked
-            if info.get("host") == "issuecdn.baidupcs.com":
-                return None
-
-            if not info.get("urls"):
+            try:
+                resp = urllib.request.urlopen(req)  # type: ignore
+
+                # Error: "user is not authorized"
+                # This error occurs when the method is called by too many times
+                if resp.status != 200:
+                    time.sleep(2)
+                    continue
+
+                info = json.loads(resp.read())
+
+                # This error is gotten when remote path is blocked
+                if info.get("host") == "issuecdn.baidupcs.com":
+                    return None
+
+                if not info.get("urls"):
+                    return None
+                else:
+                    # return info["urls"][0]["url"].replace("&htype=", "")
+                    return info["urls"][0]["url"]
+            except urllib.error.HTTPError as e:
+                print(f"Error Code:{e.code}")
                 return None
-            else:
-                # return info["urls"][0]["url"].replace("&htype=", "")
-                return info["urls"][0]["url"]
 
     def file_stream(
         self,