Bug reports, and suchlike

[ebooks-forum]

Hello, members of the Sigil forum. My name is J. Altman, and I am a new member; I have joined this forum to ask one question, and perhaps to follow Sigil news and such.

I have read the documents on the issue(s) around Open Source, so I have some understanding of the hurdles faced by Sigil in that area.

That said, I have a query.

I use Sigil on an Open Source OS, FreeBSD (also, briefly, PC-BSD); and I have a pair of error messages. What I cannot determine is the origin of the errors; are they specific to the OS, or something else, where something else is unknown.

Would this be an appropriate forum to inquire? I don't see a Bug Reports sticky; so I want to ask before posting.

Thanks,

J. Altman

[DiapDealer]

Yes, this would be an appropriate place to inquire. I haven't used a BSD system in a a decade or so, but I'll help if I can.

What are your errors and what are you doing when they occur? Also, what version of Sigil?

[ebooks-forum]

These are the errors:
==================

Embedded Python Error:

Traceback (most recent call last):

File "/usr/local/share/sigil/python3lib/xmlprocessor.py", line 6, in <module>
from sigil_bs4.builder._lxml import LXMLTreeBuilderForXML

File "/usr/local/share/sigil/plugin_launchers/python/sigil_bs4/builder/_lxml.py", line 26, in <module>
from lxml import etree

ImportError: No module named 'lxml'

error in xmlprocessor repairXML: -2:

Traceback (most recent call last):

File "/usr/local/share/sigil/python3lib/xmlprocessor.py", line 6, in <module>
from sigil_bs4.builder._lxml import LXMLTreeBuilderForXML

File "/usr/local/share/sigil/plugin_launchers/python/sigil_bs4/builder/_lxml.py", line 26, in <module>
from lxml import etree

ImportError: No module named 'lxml'

==============

These repeat, for several times; sometimes, Sigil hangs and dumps core; where the core file is:

du -ch sigil.core
1.1G sigil.core
1.1G total

Other times, it does not hang nor dump core.

I could post what I am pretty sure is the source code. Also, my concerns: (1) is the error something critical? It doesn't seem to be; but I'd rather not commit a bunch of work to an ebook before knowing....(2) is the origin of the error upstream from FreeBSD, or elsewhere, perhaps in the ports tree for FreeBSD?

Thanks for your time,

J. Altman

[KevinH]

Sigil requires that the python3 interpreter have a number of specific python3 packages installed to allow Sigil to work. These include lxml. Without it Sigil will not be stable and should not be used.

Please check the building on Linux instructions for a list of python packages that should be installed to make your python3 interpreter equivalent to what Sigil packages internally on Windows and Mac. You can probably use pip3 install lxml to install it for your python3.

Your package management system may have these packages as well.

Here is the list of python packages to add and the python commands to install them on most unix like systems.

sudo pip3 install six
sudo pip3 install html5lib
sudo pip3 install lxml
sudo pip3 install beautifulsoup4
sudo pip3 install Pillow
sudo pip3 install regex
sudo pip3 install cssutils
sudo pip3 install cssselect
sudo pip3 install charset

[KevinH]

BTW, under Sigil's Plugin forum you should find a testplugin_012.zip that you can install into Sigil once you have added those python3 modules, to test your setup.

[DiapDealer]

Yes. The lxml Python module is a critical component of Sigil (even if you have no plans to use the plugin framework). If you're using a version of Sigil from the FreeBSD ports tree, then someone upstream is probably neglecting to include lxml as a dependency.

If you're familiar with installing Python modules, you can either install it (lxml) via your OS's package management system (sorry, I have no idea what naming conventions FreeBSD uses for Python module packages), or use Python's "pip" to install it.

The barest of Python3 necessities for a functional Sigil installation would be the 'lxml' and 'six' modules. But if you plan on using plugins, the full list of Python modules that plugin developers can count on being available on other systems are:

six
lxml
html5lib
regex
Pillow
cssselect
cssutils
chardet
(many plugins also use tkinter in case that's not included with your Python3).

But six and lxml will get you by (though installing the other modules is highly recommended).

Oops! Kevin beat me!
(though I don't think bs4 is technically needed since our own version of bs4 is included [if the upstream maintainer didn't mess up]).

[KevinH]

Yes, my mistake. BeautfulSoup4 is no longer needed since we have our own sigil_bs4 version.

I'll have to update the MacOSX build instructions to fix that.

KevinH

[ebooks-forum]

There are only a few things with lxml that I see in the ports tree; and these two seem like the most likely suspects:

Port: py27-lxml-3.5.0
Path: /usr/ports/devel/py-lxml
Info: Pythonic binding for the libxml2 and libxslt libraries

Port: tclxml-3.3
Path: /usr/ports/devel/tclxml
Info: API for parsing XML documents using Tcl

I'm assuming it is the first?

Thank you for the replies; I'll ask someone within the FreeBSD community for further information.

[DiapDealer]

You need lxml for Python3, not Python2.

[ebooks-forum]

Ah, right; I see. Thanks.

[eschwartz]

Hmm, difficult to add Python3 lxml as a dependency if FreeBSD doesn't include packages for the Python3 version of modules.

And from my cursory inspection of the availability of packages for an OS I don't actually use they seem to only provide Python2 versions of things.

[duns]

I am a kubuntu user (17.10) and now, with 17.10 (not wuth 17.04), I get this error message: "Traceback (most recent call last):
File "/usr/local/share/sigil/python3lib/xmlprocessor.py", line 6, in <module>
from sigil_bs4.builder._lxml import LXMLTreeBuilderForXML
File "/usr/local/share/sigil/plugin_launchers/python/sigil_bs4/builder/_lxml.py", line 26, in <module>
from lxml import etree
ImportError: cannot import name 'etree'".
I installed all you have suggested, but I get always the same error message (after 30 error message Sigil start, but when I save the file, other 30 error messages).
Thank you

[duns]

Useless comment the line "# from lxml import etree" in the two files

[Doitsu]

@Duns: This issue has been reported before. See this bug report thread for more information.

If you're 100% sure that you've installed all packages, you might have to add the package path to the Python sys path.

[DiapDealer]

It sounds to me as if the lxml python3 module isn't installed. Commenting out imports from Sigil's custom bs4 module is not going to "fix" the problem. It will just move it. The fix is to make sure all required python3 modules are installed:

sudo apt-get install python3-lxml python3-six

In order to make full use of the available 3rd-party plugins for Sigil, you'll also want to make sure the following recommended python3 modules are installed.

sudo apt-get install python3-tk python3-pyqt5 python3-html5lib python3-regex python3-pillow python3-cssselect python3-cssutils python3-chardet