Fetching folder by FolderId within virtual environments

[falsaub]

Hi, I am using your library to read items from shared calendars which are listed in OWA as "Other calendars". This is working fine when the package is installed system-wide but not within virtual environments.

I have created a virtual environment using venv and installed your package. When reading "Other calendars" by their folder id, I retrieve items from the default calendar instead. When the virtual environment is deactivated I retrieve items from the other calendars as expected. I am using this code:

folder = SingleFolderQuerySet( account = a, folder = a.root, ).get(id = "MY_FOLDER_ID")

I have tried another piece of code found at #1184. Outside of the virtual environment I retrieve items from the other calendar as expected. Activating the virtual environment I am getting an error:

folder = SingleFolderQuerySet( account = a, folder = FolderId(id = "MY_FOLDER_ID"), ).resolve()

Traceback (most recent call last):
  File "/.../exchange.py", line 73, in <module>
    ).resolve()
      ^^^^^^^^^
  File "/.../my-venv/lib/python3.11/site-packages/exchangelib/folders/queryset.py", line 187, in resolve
    return list(self.folder_collection.resolve())[0]
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/.../my-venv/lib/python3.11/site-packages/exchangelib/folders/collections.py", line 335, in resolve
    yield from self.__class__(account=self.account, folders=resolveable_folders).get_folders(
  File "/.../my-venv/lib/python3.11/site-packages/exchangelib/folders/collections.py", line 403, in get_folders
    yield from GetFolder(account=self.account).call(
  File "/.../my-venv/lib/python3.11/site-packages/exchangelib/services/get_folder.py", line 55, in _elems_to_objs
    yield parse_folder_elem(elem=elem, folder=folder)
          ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/.../my-venv/lib/python3.11/site-packages/exchangelib/services/common.py", line 979, in parse_folder_elem
    raise ValueError(f"Unsupported folder class: {folder}")
ValueError: Unsupported folder class: FolderId(id='MY_FOLDER_ID')

Do you have any tips to get it working in virtual environments?

Thank you in advance.

[ecederstrand]

That’s super weird. exchangelib shouldn’t care at all whether it’s installed system-wide or in a venv. There must be some Python or package version difference between the two, difference in SSL certificate verification or something entirely different. I don’t have any suggestions except enabling debug logging and checking where the two versions deviate.

[falsaub]

Hi, I couldn't find any difference between the configurations of the virtual and system-wide environments, so I tested another operating system.

Debian 12 installs exchangelib version 4.9.0. Here, reading the "Other Calendars" works fine, even in the virtual environment.

Debian 13 installs exchangelib version 5.6.0. Here, the errors mentioned above occur in the virtual environment. The same applies to version 5.5.1.

When I install exchanglib 4.9.0 under Debian 13, no errors occur and I can retrieve the desired calendar entries in the virtual environment.

What difference in the source code of the two versions could cause this behaviour? Ideally, I would like to switch to the latest version of your package.

[ecederstrand]

The diff between the versions you mention is very large. I would still suggest enabling debug logging and checking where the working and non-working versions deviate.

[falsaub]

I followed your advice and enabled debug logging. There is a significant difference when accessing the folder id.

Version 4.9.0 uses the FolderId class and thus retrieves the desired entries from the "Other calendar".

DEBUG:exchangelib.folders.base:Folder class <class 'exchangelib.folders.known_folders.Calendar'> matches container class IPF.Appointment (Kalender)
[...]
DEBUG:exchangelib.util.xml:Request XML: <?xml version='1.0' encoding='utf-8'?>
[...]
      <m:ParentFolderIds>
        <t:FolderId Id="MY_FOLDER_ID" ChangeKey="MY_CHANGE_KEY"/>
      </m:ParentFolderIds>
[...]

Version 5.6.0 uses the DistinguishedFolderId class and tries to impersonate an account. However, the "Other calendar" cannot be accessed this way and the entries from the accounts default calendar are returned instead.

DEBUG:exchangelib.folders.base:Folder class <class 'exchangelib.folders.known_folders.Calendar'> matches container class IPF.Appointment (Kalender)
[...]
DEBUG:exchangelib.util.xml:Request XML: <?xml version='1.0' encoding='utf-8'?>
[...]
      <m:ParentFolderIds>
        <t:DistinguishedFolderId Id="calendar">
          <t:Mailbox>
            <t:EmailAddress>MY_PRIMARY_SMTP_ADDRESS</t:EmailAddress>
            <t:RoutingType>SMTP</t:RoutingType>
            <t:MailboxType>Mailbox</t:MailboxType>
          </t:Mailbox>
        </t:DistinguishedFolderId>
      </m:ParentFolderIds>
[...]

Can I prevent the usage of the DistinguishedFolderId class in any way?

[ecederstrand]

Did you try the example on connecting to shared folders described in https://ecederstrand.github.io/exchangelib/#setup-and-connecting ? I don't have access to a test setup with shared folders so I can't test myself, unfortunately.

[falsaub]

I tried your example on connecting to a shared folder using the SingleFolderQuerySet and DistinguishedFolderId classes, but it returns an error in both exchangelib versions:

DEBUG:exchangelib.util.xml:Request XML: <?xml version='1.0' encoding='utf-8'?>
[...]
      <m:FolderIds>
        <t:DistinguishedFolderId Id="MY_FOLDER_ID">
          <t:Mailbox>
            <t:EmailAddress>MY_PRIMARY_SMTP_ADDRESS</t:EmailAddress>
            <t:RoutingType>SMTP</t:RoutingType>
            <t:MailboxType>Mailbox</t:MailboxType>
          </t:Mailbox>
        </t:DistinguishedFolderId>
      </m:FolderIds>
[...]
exchangelib.errors.ErrorInvalidSchemaVersionForMailboxVersion: Tried versions ('Exchange2016', 'Exchange2019', 'Exchange2015_SP1', 'Exchange2015', 'Exchange2013_SP1', 'Exchange2013', 'Exchange2010_SP2', 'Exchange2010_SP1', 'Exchange2010', 'Exchange2007_SP1', 'Exchange2007') but all were invalid

Using impersonation within the account settings returns "exchangelib.errors.ErrorImpersonateUserDenied" in both exchangelib versions.