Use different exit codes for different failures (#2243)

docs/basic-usage.rst

@@ -314,6 +314,40 @@ when they were downloaded::
 
    instaloader --post-metadata-txt="{likes} likes, {comments} comments." <target>/*.json.xz
 
+.. _exit_codes:
+
+Exit codes
+^^^^^^^^^^
+
+Different exit codes are used to indicate different kinds of error:
+
+0
+  No error, all downloads were successful.
+
+1
+  A non-fatal error happened. One or more posts, or even one or more
+  profiles could not be downloaded, but execution was not stopped. The
+  errors are repeated at the end of the log for easy access.
+
+2
+  Command-line error. An unrecognized option was passed, or an invalid
+  combination of options, for example. No interaction with Instagram
+  was made.
+
+3
+  Login error. It was not possible to login. Downloads were not
+  attempted.
+
+4
+  Fatal download error. Downloads were interrupted and no further
+  attempts were made. Happens when a response with one of the status
+  codes in the :option:`--abort-on` option were passed, or when
+  Instagram logs the user out during downloads.
+
+5
+  Interrupted by the user. Happens when the user presses Control-C or
+  sends SIGINT to the process.
+
 .. _instaloader-as-cronjob:
 
 Instaloader as Cronjob

docs/module/exceptions.rst

@@ -27,16 +27,26 @@ Exceptions
 
 .. autoexception:: LoginRequiredException
 
+.. autoexception:: LoginException
+
+   .. versionadded:: 4.12
+
 .. autoexception:: TwoFactorAuthRequiredException
 
    .. versionadded:: 4.2
 
+   .. versionchanged:: 4.12
+      Inherits LoginException
+
 .. autoexception:: InvalidArgumentException
 
 .. autoexception:: BadResponseException
 
 .. autoexception:: BadCredentialsException
 
+   .. versionchanged:: 4.12
+      Inherits LoginException
+
 .. autoexception:: PostChangedException
 
 .. autoexception:: QueryReturnedNotFoundException

instaloader/__main__.py

@@ -7,10 +7,11 @@ import re
 import sys
 import textwrap
 from argparse import ArgumentParser, ArgumentTypeError, SUPPRESS
+from enum import IntEnum
 from typing import List, Optional
 
 from . import (AbortDownloadException, BadCredentialsException, Instaloader, InstaloaderException,
-               InvalidArgumentException, Post, Profile, ProfileNotExistsException, StoryItem,
+               InvalidArgumentException, LoginException, Post, Profile, ProfileNotExistsException, StoryItem,
                TwoFactorAuthRequiredException, __version__, load_structure_from_file)
 from .instaloader import (get_default_session_filename, get_default_stamps_filename)
 from .instaloadercontext import default_user_agent
@@ -22,6 +23,15 @@ except ImportError:
     bc3_library = False
 
 
+class ExitCode(IntEnum):
+    SUCCESS = 0
+    NON_FATAL_ERROR = 1
+    INIT_FAILURE = 2
+    LOGIN_FAILURE = 3
+    DOWNLOAD_ABORTED = 4
+    USER_ABORTED = 5
+    UNEXPECTED_ERROR = 99
+
 def usage_string():
     # NOTE: duplicated in README.rst and docs/index.rst
     argv0 = os.path.basename(sys.argv[0])
@@ -84,9 +94,8 @@ def get_cookies_from_instagram(domain, browser, cookie_file='', cookie_name=''):
     }
 
     if browser not in supported_browsers:
-        print("Loading cookies from the specified browser failed")
+        raise InvalidArgumentException("Loading cookies from the specified browser failed\n"
-        print("Supported browsers are Chrome, Firefox, Edge, Brave, Opera and Safari")
+                                       "Supported browsers are Chrome, Firefox, Edge, Brave, Opera and Safari")
-        return {}
 
     cookies = {}
     browser_cookies = list(supported_browsers[browser](cookie_file=cookie_file))
@@ -98,7 +107,8 @@ def get_cookies_from_instagram(domain, browser, cookie_file='', cookie_name=''):
     if cookies:
         print(f"Cookies loaded successfully from {browser}")
     else:
-        print(f"No cookies found for Instagram in {browser}, Are you logged in succesfully in {browser}?")
+        raise LoginException(f"No cookies found for Instagram in {browser}, "
+                             f"Are you logged in succesfully in {browser}?")
 
     if cookie_name:
         return cookies.get(cookie_name, {})
@@ -112,7 +122,7 @@ def import_session(browser, instaloader, cookiefile):
         instaloader.context.update_cookies(cookie)
         username = instaloader.test_login()
         if not username:
-            raise SystemExit(f"Not logged in. Are you logged in successfully in {browser}?")
+            raise LoginException(f"Not logged in. Are you logged in successfully in {browser}?")
         instaloader.context.username = username
         print(f"{username} has been successfully logged in.")
         next_step_text = (f"Next: Run instaloader --login={username} as it is required to download high quality media "
@@ -133,7 +143,7 @@ def _main(instaloader: Instaloader, targetlist: List[str],
           max_count: Optional[int] = None, post_filter_str: Optional[str] = None,
           storyitem_filter_str: Optional[str] = None,
           browser: Optional[str] = None,
-          cookiefile: Optional[str] = None) -> None:
+          cookiefile: Optional[str] = None) -> ExitCode:
     """Download set of profiles, hashtags etc. and handle logging in and session files if desired."""
     # Parse and generate filter function
     post_filter = None
@@ -152,7 +162,7 @@ def _main(instaloader: Instaloader, targetlist: List[str],
     if browser and bc3_library:
         import_session(browser.lower(), instaloader, cookiefile)
     elif browser and not bc3_library:
-        raise SystemExit("browser_cookie3 library is needed to load cookies from browsers")
+        raise InvalidArgumentException("browser_cookie3 library is needed to load cookies from browsers")
     # Login, if desired
     if username is not None:
         if not re.match(r"^[A-Za-z0-9._]+$", username):
@@ -189,6 +199,7 @@ def _main(instaloader: Instaloader, targetlist: List[str],
     # Try block for KeyboardInterrupt (save session on ^C)
     profiles = set()
     anonymous_retry_profiles = set()
+    exit_code = ExitCode.SUCCESS
     try:
         # Generate set of profiles, already downloading non-profile targets
         for target in targetlist:
@@ -294,8 +305,10 @@ def _main(instaloader: Instaloader, targetlist: List[str],
                                                    latest_stamps=latest_stamps)
     except KeyboardInterrupt:
         print("\nInterrupted by user.", file=sys.stderr)
+        exit_code = ExitCode.USER_ABORTED
     except AbortDownloadException as exc:
         print("\nDownload aborted: {}.".format(exc), file=sys.stderr)
+        exit_code = ExitCode.DOWNLOAD_ABORTED
     # Save session if it is useful
     if instaloader.context.is_logged_in:
         instaloader.save_session_to_file(sessionfile)
@@ -307,6 +320,8 @@ def _main(instaloader: Instaloader, targetlist: List[str],
         else:
             # Instaloader did not do anything
             instaloader.context.log("usage:" + usage_string())
+            exit_code = ExitCode.INIT_FAILURE
+    return exit_code
 
 
 def main():
@@ -488,10 +503,10 @@ def main():
             print("--login=USERNAME required to download stories.", file=sys.stderr)
             args.stories = False
             if args.stories_only:
-                raise SystemExit(1)
+                raise InvalidArgumentException()
 
         if ':feed-all' in args.profile or ':feed-liked' in args.profile:
-            raise SystemExit(":feed-all and :feed-liked were removed. Use :feed as target and "
+            raise InvalidArgumentException(":feed-all and :feed-liked were removed. Use :feed as target and "
                                            "eventually --post-filter=viewer_has_liked.")
 
         post_metadata_txt_pattern = '\n'.join(args.post_metadata_txt) if args.post_metadata_txt else None
@@ -502,18 +517,18 @@ def main():
                 post_metadata_txt_pattern = ''
                 storyitem_metadata_txt_pattern = ''
             else:
-                raise SystemExit("--no-captions and --post-metadata-txt or --storyitem-metadata-txt given; "
+                raise InvalidArgumentException("--no-captions and --post-metadata-txt or --storyitem-metadata-txt "
-                                 "That contradicts.")
+                                               "given; That contradicts.")
 
         if args.no_resume and args.resume_prefix:
-            raise SystemExit("--no-resume and --resume-prefix given; That contradicts.")
+            raise InvalidArgumentException("--no-resume and --resume-prefix given; That contradicts.")
         resume_prefix = (args.resume_prefix if args.resume_prefix else 'iterator') if not args.no_resume else None
 
         if args.no_pictures and args.fast_update:
-            raise SystemExit('--no-pictures and --fast-update cannot be used together.')
+            raise InvalidArgumentException('--no-pictures and --fast-update cannot be used together.')
 
         if args.login and args.load_cookies:
-            raise SystemExit('--load-cookies and --login cannot be used together.')
+            raise InvalidArgumentException('--load-cookies and --login cannot be used together.')
 
         # Determine what to download
         download_profile_pic = not args.no_profile_pic or args.profile_pic_only
@@ -538,7 +553,7 @@ def main():
                              iphone_support=not args.no_iphone,
                              title_pattern=args.title_pattern,
                              sanitize_paths=args.sanitize_paths)
-        _main(loader,
+        exit_code = _main(loader,
                           args.profile,
                           username=args.login.lower() if args.login is not None else None,
                           password=args.password,
@@ -557,8 +572,18 @@ def main():
                           browser=args.load_cookies,
                           cookiefile=args.cookiefile)
         loader.close()
+        if loader.has_stored_errors:
+            exit_code = ExitCode.NON_FATAL_ERROR
+    except InvalidArgumentException as err:
+        print(err, file=sys.stderr)
+        exit_code = ExitCode.INIT_FAILURE
+    except LoginException as err:
+        print(err, file=sys.stderr)
+        exit_code = ExitCode.LOGIN_FAILURE
     except InstaloaderException as err:
-        raise SystemExit("Fatal error: %s" % err) from err
+        print("Fatal error: %s" % err)
+        exit_code = ExitCode.UNEXPECTED_ERROR
+    sys.exit(exit_code)
 
 
 if __name__ == "__main__":

instaloader/exceptions.py

@@ -33,7 +33,11 @@ class LoginRequiredException(InstaloaderException):
     pass
 
 
-class TwoFactorAuthRequiredException(InstaloaderException):
+class LoginException(InstaloaderException):
+    pass
+
+
+class TwoFactorAuthRequiredException(LoginException):
     pass
 
 
@@ -45,7 +49,7 @@ class BadResponseException(InstaloaderException):
     pass
 
 
-class BadCredentialsException(InstaloaderException):
+class BadCredentialsException(LoginException):
     pass
 
 

instaloader/instaloader.py

@@ -643,11 +643,16 @@ class Instaloader:
     def login(self, user: str, passwd: str) -> None:
         """Log in to instagram with given username and password and internally store session object.
 
-        :raises InvalidArgumentException: If the provided username does not exist.
         :raises BadCredentialsException: If the provided password is wrong.
-        :raises ConnectionException: If connection to Instagram failed.
         :raises TwoFactorAuthRequiredException: First step of 2FA login done, now call
-           :meth:`Instaloader.two_factor_login`."""
+           :meth:`Instaloader.two_factor_login`.
+        :raises LoginException: An error happened during login (for example, an invalid response was received).
+           Or if the provided username does not exist.
+
+        .. versionchanged:: 4.12
+           Raises LoginException instead of ConnectionException when an error happens.
+           Raises LoginException instead of InvalidArgumentException when the username does not exist.
+        """
         self.context.login(user, passwd)
 
     def two_factor_login(self, two_factor_code) -> None:
@@ -1582,11 +1587,16 @@ class Instaloader:
     def interactive_login(self, username: str) -> None:
         """Logs in and internally stores session, asking user for password interactively.
 
-        :raises LoginRequiredException: when in quiet mode.
+        :raises InvalidArgumentException: when in quiet mode.
-        :raises InvalidArgumentException: If the provided username does not exist.
+        :raises LoginException: If the provided username does not exist.
-        :raises ConnectionException: If connection to Instagram failed."""
+        :raises ConnectionException: If connection to Instagram failed.
+
+        .. versionchanged:: 4.12
+           Raises InvalidArgumentException instead of LoginRequiredException when in quiet mode.
+           Raises LoginException instead of InvalidArgumentException when the username does not exist.
+        """
         if self.context.quiet:
-            raise LoginRequiredException("Quiet mode requires given password or valid session file.")
+            raise InvalidArgumentException("Quiet mode requires given password or valid session file.")
         try:
             password = None
             while password is None:
@@ -1605,3 +1615,10 @@ class Instaloader:
                 except BadCredentialsException as err:
                     print(err, file=sys.stderr)
                     pass
+
+    @property
+    def has_stored_errors(self) -> bool:
+        """Returns whether any error has been reported and stored to be repeated at program termination.
+
+        .. versionadded: 4.12"""
+        return self.context.has_stored_errors

instaloader/instaloadercontext.py

@@ -151,6 +151,13 @@ class InstaloaderContext:
         if repeat_at_end:
             self.error_log.append(msg)
 
+    @property
+    def has_stored_errors(self) -> bool:
+        """Returns whether any error has been reported and stored to be repeated at program termination.
+
+        .. versionadded: 4.12"""
+        return bool(self.error_log)
+
     def close(self):
         """Print error log and close session"""
         if self.error_log and not self.quiet:
@@ -242,11 +249,16 @@ class InstaloaderContext:
     def login(self, user, passwd):
         """Not meant to be used directly, use :meth:`Instaloader.login`.
 
-        :raises InvalidArgumentException: If the provided username does not exist.
         :raises BadCredentialsException: If the provided password is wrong.
-        :raises ConnectionException: If connection to Instagram failed.
         :raises TwoFactorAuthRequiredException: First step of 2FA login done, now call
-           :meth:`Instaloader.two_factor_login`."""
+           :meth:`Instaloader.two_factor_login`.
+        :raises LoginException: An error happened during login (for example, and invalid response).
+           Or if the provided username does not exist.
+
+        .. versionchanged:: 4.12
+           Raises LoginException instead of ConnectionException when an error happens.
+           Raises LoginException instead of InvalidArgumentException when the username does not exist.
+        """
         # pylint:disable=import-outside-toplevel
         import http.client
         # pylint:disable=protected-access
@@ -277,7 +289,7 @@ class InstaloaderContext:
             resp_json = login.json()
 
         except json.decoder.JSONDecodeError as err:
-            raise ConnectionException(
+            raise LoginException(
                 "Login error: JSON decode fail, {} - {}.".format(login.status_code, login.reason)
             ) from err
         if resp_json.get('two_factor_required'):
@@ -289,31 +301,31 @@ class InstaloaderContext:
                                             resp_json['two_factor_info']['two_factor_identifier'])
             raise TwoFactorAuthRequiredException("Login error: two-factor authentication required.")
         if resp_json.get('checkpoint_url'):
-            raise ConnectionException("Login: Checkpoint required. Point your browser to "
+            raise LoginException("Login: Checkpoint required. Point your browser to "
                                  "https://www.instagram.com{} - "
                                  "follow the instructions, then retry.".format(resp_json.get('checkpoint_url')))
         if resp_json['status'] != 'ok':
             if 'message' in resp_json:
-                raise ConnectionException("Login error: \"{}\" status, message \"{}\".".format(resp_json['status'],
+                raise LoginException("Login error: \"{}\" status, message \"{}\".".format(resp_json['status'],
                                                                                           resp_json['message']))
             else:
-                raise ConnectionException("Login error: \"{}\" status.".format(resp_json['status']))
+                raise LoginException("Login error: \"{}\" status.".format(resp_json['status']))
         if 'authenticated' not in resp_json:
             # Issue #472
             if 'message' in resp_json:
-                raise ConnectionException("Login error: Unexpected response, \"{}\".".format(resp_json['message']))
+                raise LoginException("Login error: Unexpected response, \"{}\".".format(resp_json['message']))
             else:
-                raise ConnectionException("Login error: Unexpected response, this might indicate a blocked IP.")
+                raise LoginException("Login error: Unexpected response, this might indicate a blocked IP.")
         if not resp_json['authenticated']:
             if resp_json['user']:
                 # '{"authenticated": false, "user": true, "status": "ok"}'
                 raise BadCredentialsException('Login error: Wrong password.')
             else:
                 # '{"authenticated": false, "user": false, "status": "ok"}'
-                # Raise InvalidArgumentException rather than BadCredentialException, because BadCredentialException
+                # Raise LoginException rather than BadCredentialException, because BadCredentialException
                 # triggers re-asking of password in Instaloader.interactive_login(), which makes no sense if the
                 # username is invalid.
-                raise InvalidArgumentException('Login error: User {} does not exist.'.format(user))
+                raise LoginException('Login error: User {} does not exist.'.format(user))
         # '{"authenticated": true, "user": true, "userId": ..., "oneTapPrompt": false, "status": "ok"}'
         session.headers.update({'X-CSRFToken': login.cookies['csrftoken']})
         self._session = session