improve extractor.request()

- better retry behavior
- exponential back-off
- removed 'allow_empty' argument

gallery_dl/extractor/artstation.py

@@ -73,7 +73,7 @@ class ArtstationExtractor(Extractor):
     def get_user_info(self, username):
         """Return metadata for a specific user"""
         url = "{}/users/{}/quick.json".format(self.root, username.lower())
-        response = self.request(url, fatal=False, allow_empty=True)
+        response = self.request(url, fatal=False)
         if response.status_code == 404:
             raise exception.NotFoundError("user")
         return response.json()

gallery_dl/extractor/common.py

@@ -52,34 +52,34 @@ class Extractor():
             ("extractor", self.category, self.subcategory, key), default)
 
     def request(self, url, method="GET", encoding=None, fatal=True, retries=3,
-                allow_empty=False, *args, **kwargs):
-        max_retries = retries
+                *args, **kwargs):
+        max_tries = retries
         while True:
             try:
-                response = None
                 response = self.session.request(method, url, *args, **kwargs)
-                if fatal:
-                    response.raise_for_status()
-                if encoding:
-                    response.encoding = encoding
-                if response.content or allow_empty:
-                    return response
-                msg = "empty response body"
-            except requests.exceptions.HTTPError as exc:
+            except (requests.ConnectionError, requests.Timeout) as exc:
                 msg = exc
-                code = response.status_code
-                if 400 <= code < 500 and code != 429:  # Client Error
-                    retries = 0
             except requests.exceptions.RequestException as exc:
-                msg = exc
-            if not retries:
-                raise exception.HttpError(msg)
-            if response and response.status_code == 429:  # Too Many Requests
-                waittime = float(response.headers.get("Retry-After", 10.0))
+                raise exception.HttpError(exc)
             else:
-                waittime = 1
+                if 200 <= response.status_code < 400 or not fatal:
+                    if encoding:
+                        response.encoding = encoding
+                    return response
+
+                msg = "{} HTTP Error: {} for url: {}".format(
+                    response.status_code, response.reason, url)
+                if response.status_code < 500 and response.status_code != 429:
+                    break
+
+            if not retries:
+                break
+            tries = max_tries - retries
             retries -= 1
-            time.sleep(waittime * (max_retries - retries))
+            self.log.debug("%s (%d/%d)", msg, tries, max_tries)
+            time.sleep(2 ** tries)
+
+        raise exception.HttpError(msg)
 
     def _get_auth_info(self):
         """Return authentication information as (username, password) tuple"""

gallery_dl/extractor/hentaifoundry.py

@@ -142,7 +142,7 @@ class HentaifoundryUserExtractor(HentaifoundryExtractor):
             "filter_type": 0,
         }
         self.request("https://www.hentai-foundry.com/site/filters",
-                     method="post", data=formdata, allow_empty=True)
+                     method="post", data=formdata)
 
 
 class HentaifoundryImageExtractor(HentaifoundryExtractor):

gallery_dl/extractor/nijie.py

@@ -193,8 +193,8 @@ class NijieImageExtractor(NijieExtractor):
         self.page = ""
 
     def get_job_metadata(self):
-        response = self.request(self.popup_url + self.image_id,
-                                allow_redirects=False, allow_empty=True)
+        response = self.request(
+            self.popup_url + self.image_id, allow_redirects=False)
         if 300 <= response.status_code < 400:
             raise exception.NotFoundError("image")
         self.page = response.text