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DaltonST · 12-19-2019, 01:04 PM

Users are going to upgrade to the Python 3 version of Calibre just like they always have. They will upgrade it, then start the new Calibre 4.99+ that uses Python 3. Therein lies an important "FYI".

This FYI can be easily demonstrated by Win10 .bat commands in this sequence:

cd "C:\Program Files\Calibre2\" # Python 2
calibre-customize -b "any_plugin_here"
calibre
REM [all is good so far...]
cd "C:\Program Files (x86)\Calibre2\" # Python 3
calibre
REM [Calibre fails with nonsense, such as a standard Calibre library component is missing. False error.]

Why? Because calibre-customize was Python 2, so when the Python 3 was started without first updating the plugin with calibre-customize for Python 3, Calibre fails the very first time it runs.

Execute Py3 Calibre again, and it works fine.

So, the FYI is that users should not be shocked if Calibre 4.99+ immediately fails the very first time they run it after upgrading, and need only run it again.

Just something to be aware of "in real life".

Added: Obviously, when a normal user adds or updates a plugin, they do so through Preferences > Plugins, which then adds/updates the specified plugin just like 'calibre-customize -b "any_plugin_here" ' would do via CLI. The method is different, but the result is the same.

DaltonST

12-19-2019, 01:04 PM	#55
DaltonST Deviser Posts: 2,265 Karma: 2090983 Join Date: Aug 2013 Location: Texas Device: none	FYI for Users Who Run for First Time Calibre Just Upgraded to 4.99 Users are going to upgrade to the Python 3 version of Calibre just like they always have. They will upgrade it, then start the new Calibre 4.99+ that uses Python 3. Therein lies an important "FYI". This FYI can be easily demonstrated by Win10 .bat commands in this sequence: cd "C:\Program Files\Calibre2\" # Python 2 calibre-customize -b "any_plugin_here" calibre REM [all is good so far...] cd "C:\Program Files (x86)\Calibre2\" # Python 3 calibre REM [Calibre fails with nonsense, such as a standard Calibre library component is missing. False error.] Why? Because calibre-customize was Python 2, so when the Python 3 was started without first updating the plugin with calibre-customize for Python 3, Calibre fails the very first time it runs. Execute Py3 Calibre again, and it works fine. So, the FYI is that users should not be shocked if Calibre 4.99+ immediately fails the very first time they run it after upgrading, and need only run it again. Just something to be aware of "in real life". Added: Obviously, when a normal user adds or updates a plugin, they do so through Preferences > Plugins, which then adds/updates the specified plugin just like 'calibre-customize -b "any_plugin_here" ' would do via CLI. The method is different, but the result is the same. DaltonST Last edited by DaltonST; 12-19-2019 at 03:15 PM.