overhaul exception stuff

gallery_dl/exception.py

@@ -1,6 +1,6 @@
 # -*- coding: utf-8 -*-
 
-# Copyright 2015-2018 Mike Fährmann
+# Copyright 2015-2019 Mike Fährmann
 #
 # This program is free software; you can redistribute it and/or modify
 # it under the terms of the GNU General Public License version 2 as
@@ -17,63 +17,90 @@ Exception
       |    +-- AuthorizationError
       |    +-- NotFoundError
       |    +-- HttpError
-      +-- DownloadError
-      |    +-- DownloadComplete
-      |    +-- DownloadRetry
-      +-- NoExtractorError
       +-- FormatError
+      |    +-- FilenameFormatError
+      |    +-- DirectoryFormatError
       +-- FilterError
+      +-- NoExtractorError
       +-- StopExtraction
 """
 
 
 class GalleryDLException(Exception):
     """Base class for GalleryDL exceptions"""
+    default = None
+    msgfmt = None
+    code = 1
+
+    def __init__(self, message=None):
+        if not message:
+            message = self.default
+        elif isinstance(message, Exception):
+            message = "{}: {}".format(message.__class__.__name__, message)
+        if self.msgfmt:
+            message = self.msgfmt.format(message)
+        Exception.__init__(self, message)
 
 
 class ExtractionError(GalleryDLException):
     """Base class for exceptions during information extraction"""
 
 
+class HttpError(ExtractionError):
+    """HTTP request during data extraction failed"""
+    default = "HTTP request failed"
+    code = 4
+
+
+class NotFoundError(ExtractionError):
+    """Requested resource (gallery/image) could not be found"""
+    msgfmt = "Requested {} could not be found"
+    default = "resource (gallery/image)"
+    code = 8
+
+
 class AuthenticationError(ExtractionError):
-    """Invalid or missing login information"""
+    """Invalid or missing login credentials"""
+    default = "Invalid or missing login credentials"
+    code = 16
 
 
 class AuthorizationError(ExtractionError):
     """Insufficient privileges to access a resource"""
-
+    default = "Insufficient privileges to access a resource"
-
+    code = 16
-class NotFoundError(ExtractionError):
-    """Requested resource (gallery/image) does not exist"""
-
-
-class HttpError(ExtractionError):
-    """HTTP request during extraction failed"""
-
-
-class DownloadError(GalleryDLException):
-    """Base class for exceptions during file downloads"""
-
-
-class DownloadRetry(DownloadError):
-    """Download attempt failed and should be retried"""
-
-
-class DownloadComplete(DownloadError):
-    """Output file of attempted download is already complete"""
-
-
-class NoExtractorError(GalleryDLException):
-    """No extractor can handle the given URL"""
 
 
 class FormatError(GalleryDLException):
-    """Error while building output path"""
+    """Error while building output paths"""
+    code = 32
+
+
+class FilenameFormatError(FormatError):
+    """Error while building output filenames"""
+    msgfmt = "Applying filename format string failed ({})"
+
+
+class DirectoryFormatError(FormatError):
+    """Error while building output directory paths"""
+    msgfmt = "Applying directory format string failed ({})"
 
 
 class FilterError(GalleryDLException):
     """Error while evaluating a filter expression"""
+    msgfmt = "Evaluating filter expression failed ({})"
+    code = 32
+
+
+class NoExtractorError(GalleryDLException):
+    """No extractor can handle the given URL"""
+    code = 64
 
 
 class StopExtraction(GalleryDLException):
-    """Extraction should stop"""
+    """Stop data extraction"""
+
+    def __init__(self, message=None):
+        GalleryDLException.__init__(self)
+        self.message = message
+        self.code = 1 if message else 0

gallery_dl/job.py

@@ -46,34 +46,18 @@ class Job():
             log = self.extractor.log
             for msg in self.extractor:
                 self.dispatch(msg)
-        except exception.AuthenticationError as exc:
+        except exception.StopExtraction as exc:
-            msg = str(exc) or "Please provide a valid username/password pair."
+            if exc.message:
-            log.error("Authentication failed: %s", msg)
+                log.error("%s", exc.message)
-        except exception.AuthorizationError:
+            return exc.code
-            log.error("You do not have permission to access the resource "
+        except exception.GalleryDLException as exc:
-                      "at '%s'", self.extractor.url)
+            log.error("%s: %s", exc.__class__.__name__, exc)
-        except exception.NotFoundError as exc:
+            return exc.code
-            res = str(exc) or "resource (gallery/image/user)"
-            log.error("The %s at '%s' does not exist", res, self.extractor.url)
-        except exception.HttpError as exc:
-            err = exc.args[0]
-            if isinstance(err, Exception):
-                err = "{}: {}".format(err.__class__.__name__, err)
-            log.error("HTTP request failed:  %s", err)
-        except exception.FormatError as exc:
-            err, obj = exc.args
-            log.error("Applying %s format string failed:  %s: %s",
-                      obj, err.__class__.__name__, err)
-        except exception.FilterError as exc:
-            err = exc.args[0]
-            log.error("Evaluating filter expression failed:  %s: %s",
-                      err.__class__.__name__, err)
-        except exception.StopExtraction:
-            pass
         except OSError as exc:
             log.error("Unable to download data:  %s: %s",
                       exc.__class__.__name__, exc)
             log.debug("", exc_info=True)
+            return 128
         except Exception as exc:
             log.error(("An unexpected error occurred: %s - %s. "
                        "Please run gallery-dl again with the --verbose flag, "
@@ -81,6 +65,9 @@ class Job():
                        "https://github.com/mikf/gallery-dl/issues ."),
                       exc.__class__.__name__, exc)
             log.debug("", exc_info=True)
+            return 1
+        else:
+            return 0
         finally:
             self.handle_finalize()
 
@@ -504,6 +491,7 @@ class DataJob(Job):
 
         # dump to 'file'
         util.dump_json(self.data, self.file, self.ascii, 2)
+        return 0
 
     def handle_url(self, url, kwdict):
         self.data.append((Message.Url, url, self._filter(kwdict)))

gallery_dl/util.py

@@ -528,7 +528,7 @@ class PathFormat():
             self.filename_formatter = Formatter(
                 filename_fmt, kwdefault).format_map
         except Exception as exc:
-            raise exception.FormatError(exc, "filename")
+            raise exception.FilenameFormatError(exc)
 
         try:
             self.directory_formatters = [
@@ -536,7 +536,7 @@ class PathFormat():
                 for dirfmt in directory_fmt
             ]
         except Exception as exc:
-            raise exception.FormatError(exc, "directory")
+            raise exception.DirectoryFormatError(exc)
 
         self.directory = self.realdirectory = ""
         self.filename = ""
@@ -616,7 +616,7 @@ class PathFormat():
                 if segment:
                     append(self.clean_segment(segment))
         except Exception as exc:
-            raise exception.FormatError(exc, "directory")
+            raise exception.DirectoryFormatError(exc)
 
         # Join path segements
         sep = os.sep
@@ -673,7 +673,7 @@ class PathFormat():
             self.filename = filename = self.clean_path(self.clean_segment(
                 self.filename_formatter(self.kwdict)))
         except Exception as exc:
-            raise exception.FormatError(exc, "filename")
+            raise exception.FilenameFormatError(exc)
 
         # Combine directory and filename to full paths
         self.path = self.directory + filename