epubcheck plugin for Sigil

[DNSB]

For what it may be worth, epubcheck 5.3.0 has been released. It's only a few hours old at this time but I tried a manual install and epubcheck worked including a couple of tests for bug fixes. The first try at an automatic update failed but a while later (2 hours), the auto update worked.

The GitHub link to the page is epubcheck 5.3.0

[KevinH]

And fwiw, I had previously filed an epubcheck bug about the missing support for the backlink epub:type attribute and received a notice that it was fixed in this release of epubcheck.

[jaad34]

Originally Posted by Doitsu

I wasn't able to reproduce this problem.

I just replaced the EPUBCheck files in the plugin folder with the EPUBCheck v5.1.0 files and changed the year of last_time_checked to:

  "last_time_checked": "2024-04-19 14:28:46.465902",

and when I ran the plugin, it downloaded and installed 5.2.1.

BTW, you can always force an upgrade by deleting the lib folder in the plugin folder.

Thanks! Deleting the lib folder I managed to update to version 5.3.0

[B10Mediaworx]

Hi, long-time lurker, longer-time formatter, one-time poster. I haven't participated in the community much because everyone here is smarter than I am.

I'm posting for a little help on the EpubCheck plugin by Doitsu (v0.4.7.1) for Sigil.

Sigil 2.7.0
Python 3.4 on 2.7.

I'm almost exclusively EPUB2 because reasons. I format professionally and use Sigil almost every single day. I have changed nothing, and this just started happening in the last couple of weeks:

Status: failed

epubcheck.jar not found!
Running update check...

*** PYTHON ERROR ***
SSL version: OpenSSL 3.0.15 3 Sep 2024
An exception of type URLError occurred.
Arguments:
(SSLCertVerificationError(5, '[SSL: CERTIFICATE_VERIFY_FAILED] certificate verify failed: unable to get local issuer certificate (_ssl.c:1028)'),)
Update found: EPUBCheck None

Downloading *** PYTHON ERROR *** An exception of type URLError occurred. Arguments: (SSLCertVerificationError(5, '[SSL: CERTIFICATE_VERIFY_FAILED] certificate verify failed: unable to get local issuer certificate (_ssl.c:1028)'),) ...
Traceback (most recent call last):
File "C:\Program Files\Sigil\plugin_launchers\python\launcher.py", line 142, in launch
self.exitcode = target_script.run(container)
~~~~~~~~~~~~~~~~~^^^^^^^^^^^
File "C:\Users\ebeet\AppData\Local\sigil-ebook\sigil\plugins\EpubCheck\plugin.py", line 293, in run
urlretrieve(browser_download_url, zip_file_name)
~~~~~~~~~~~^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "urllib\request.py", line 214, in urlretrieve
File "urllib\request.py", line 189, in urlopen
File "urllib\request.py", line 489, in open
File "urllib\request.py", line 511, in _open
File "urllib\request.py", line 466, in _call_chain
File "urllib\request.py", line 1395, in unknown_open
urllib.error.URLError: <urlopen error unknown url type: *** python error *** an exception of type urlerror occurred. arguments>
Error: <urlopen error unknown url type: *** python error *** an exception of type urlerror occurred. arguments>

It looks to ME like this fails when calling back for an update check, but I have no idea where my .jar went.

I have no idea how to fix this. I don't know Python and don't have time to learn it well enough to fix the code myself.

My questions:

1. Is this something I can fix?

2. If so, how? I have Java. I don't know where to put the .jar. I can't find a urllib folder.

3. If not, is there another packaged epubcheck plugin for Sigil? I've looked, but I can't find one, but that's not saying much because my googlefu is suboptimal.

I use pagina otherwise, but I really do miss the convenience of a one-click check.

Thanks in advance!

LizzieB/Moriah Jovan
dba B10 Mediaworx

[KevinH]

That error typically means the Python version you are using has missing or outdated web certificates which are used for secure communications on the internet. These certificates expire by a certain date in case they are ever compromised.

Python 3.4 is really really old so the certificates could just be outdated. Sigil plugins can work as far back as Python 3.4 but a much more modern and still supported version of Python is best. For example Sigil on Windows and MacOS ships with Python 3.13.2.

So which platform are you using?

If Linux, which variant? Did you build this version yourself or are you using the AppImage?

The fix is possible ..
upgrading Python, or adding in new certificates, or manually downloading the epubcheck jar file and installing it in the proper place in the plugin or plugin preferences folder which is inside your Sigil Preferences folder, or ..


But knowing your platform will tell us the easiest fix.

[JSWolf]

Originally Posted by KevinH

So which platform are you using?

@B10Mediaworx is using Windows 10 or Windows 11, Hence the line...

File "C:\Users\ebeet\AppData\Local\sigil-ebook\sigil\plugins\EpubCheck\plugin.py", line 293, in run

in the error report.

[KevinH]

But Sigil 2.7.0 on Windows does not use Python 3.4? It uses its own embedded python which should not be an issue with web certificates so ....

Could this be a really early version of Windows 10 that needs to be updated?

[Doitsu]

Originally Posted by B10Mediaworx

Sigil 2.7.0
Python 3.4 on 2.7.

The problem is most likely caused by an outdated external Python interpreter.

Is the Use Bundled Python option checked in Sigil?
If not please enable it.

Originally Posted by B10Mediaworx

1. Is this something I can fix? [...]
I don't know where to put the .jar.

epubcheck.jar and the lib folder need to be extracted to the EpubCheck plugin folder, which you can display by pressing WIN+R, pasting the following path into the Run dialog and hitting Enter.

%localappdata%\sigil-ebook\sigil\plugins\EpubCheck

The download link of the .zip file with the latest EPUBCheck java files is:

https://github.com/w3c/epubcheck/releases/download/v5.3.0/epubcheck-5.3.0.zip

If the plugin then works again go to:

%localappdata%\sigil-ebook\sigil\plugins_prefs\EpubCheck

Edit EpubCheck.json as follows:

  "github": false,
  "update_check": false,

This'll deactivate the part of the code that checks for updates.

[DiapDealer]

I'm wondering if they're mistaking the Python3.4+ label in the plugin config dialog for their version of Python.

Also: OpenSSL version 3.0.15 is far, far newer than what would be being used by Python 3.4. Whatever else might be going on, I'm betting the Python being used is the bundled 3.13.2 that comes with the Sigil 2.7.0 Windows installer.

[DiapDealer]

urllib.request uses the operating system's certificate store. It's entirely possible that Windows 10's certificate store is no longer valid. We may need to look into configuring the Windows Sigil bundle to include (and use) the certifi module by default to keep plugins that use urllib.request working on Windows 10.

Anyone know if there is a manual workaround to updating Windows 10's certificates?


EDIT: I realize that not being able to find epubcheck.jar might be the root cause here, but urllib.request not being able to get valid local certs from Windows 10 machines not getting any more updates should probably be addressed.

And Jon: if you say one thing about updating to Windows 11, your posts in this thread will be deleted.

[DiapDealer]

I was getting the same errors on my Windows 10 VM when running the EpubCheck plugin. But on subsequent attempts, it worked just fine. Not sure what's up there.

[KevinH]

FWIW, Mac has long included and used the certifi module and in the PluginRunner Dialog we explicitly set its path in this snippet. Should we be doing the same for Windows 10 (and 11)?

#ifdef Q_OS_MAC
    // On Mac OS X, it appears that QProcess does not inherit the callers process environment at all
    // which directly contradicts the Qt documentation.
    // So we simply read the system environment and set it for QProcess manually
    // so that python getpreferredencoding() and stdout/stderr/stdin encodings to get properly set
    if (settings.useBundledInterp()) {
         // determine path to site-packages/certifi/cacert.pem to set SSL_CERT_FILE
         QDir exedir(QCoreApplication::applicationDirPath());
         exedir.cdUp();
         QString cert_path = exedir.absolutePath() + PYTHON_SITE_PACKAGES + "/certifi/cacert.pem";
         env.insert("SSL_CERT_FILE", cert_path);
         env.insert("QT_PLUGIN_PATH", QDir(QCoreApplication::applicationDirPath() + "/../PlugIns").absolutePath());
         env.insert("QT_QPA_PLATFORM_PLUGIN_PATH", QDir(QCoreApplication::applicationDirPath() + "/../PlugIns/platforms").absolutePath());
    }

Since the Windows build of Sigil also includes the python certifi module in its Python site-packages, perhaps just creating an SSL_CERT_FILE environment variable and setting its value to point to the right file will be enough to fix everything (even for the current Windows 10 build of Sigil 2.7.0).

[DiapDealer]

I believe I'm doing something similar for the Linux AppImage as well. Let me do some experimenting.

[B10Mediaworx]

Goodness! I didn't think my post posted AT ALL and I didn't want to rewrite all that, so I didn't, and went back to my problem. I just NOW got an email that it posted, so I came and found all this help. Thank you!!!

I actually solved it with close attention paid to the most excellent directions here: https://www.mobileread.com/forums/sh...d.php?t=248186

I also documented exactly what I did, so here's my readme that yes, does read like a kindergartner's book:

There are TWO ZIP files for this.

EpubCheck_v0.4.7.1.zip -- The actual plugin that you insert into Sigil
epubcheck-5.3.0.zip -- The Java files that make the fucking thing run

The second one failed. The link above says to be connected to the internet so it can find the files, but maybe the link changed? I think. Not sure.

Anyway, I actually followed the directions (had to parse them, of course).

I had to extract the Java files from ZIP #2 (5.3.0) and put them in the actual plugin's folder. PATH: C:\Users\ebeet\AppData\Local\sigil-ebook\sigil\plugins\EpubCheck

DO NOT put the zip file, the primary epubcheck-5.3.0 folder, or the secondary epubcheck-5.3.0 in the EpubCheck plugin folder.

It WILL NOT automatically extract the zip file or the primary folder or the secondary folder.

Take ALL the files out of the secondary epubcheck-5.3.0 folder and put them in the EpubCheck plugin folder. That works.

In DOS:

1. Checked for Python. Not there.
2. Checked for Java. That was fine.
3. Updated a bunch of shit.

Then
4. Installed Python (but I don't know why I had to when it shows in the installed programs list).
5. Restarted.
6. Read the directions.
7. Unzipped epubcheck-5.3.0.zip
8. Put the files in the secondary epubcheck-5.3.0 extracted folder in the EpubCheck folder.
PATH: C:\Users\ebeet\AppData\Local\sigil-ebook\sigil\plugins\EpubCheck

All done.

I really really really want to thank this community, even though I didn't slowly introduce myself AND I did the unthinkable and asked for help straight out of the gate, which is poor internet etiquette (hello, Usenet and IRC). I learned how to format ebooks when I published myself way back in 2008. I was doing a whole laundry list of formats back then: LIT, IMP, PDB, PRC/MOBI, HTML.

Then when Smashwords came online, I actually broke the meatgrinder. Twice. In the same weekend. That's how they figured out you couldn't upload HTML or RTF.

And so I hung out my shingle. I've been using Sigil since almost the very beginning, and let me tell you. I am sooooooo happy to be able to do only ONE format now (not including PDF, which is typesetting, not markup).

Self-publishing has come so far since I started (took a lot of heat for it too), but I know I can come back here and (probably) find the answer to any question I have.

Thank you so much!

PS Yes, I'm on Win10 and I intend to stay on it as long as I possibly can.

As for Linux, I was thinking about building a Linux box way back in 2000, and still haven't done it. My husband did build me a Hackintosh a few years ago, but then Dan Poynter gave me one of his old MacBooks, so I used that when I had to upload to iBooks.

[pdurrant]

Originally Posted by B10Mediaworx

Goodness! I didn't think my post posted AT ALL and I didn't want to rewrite all that, so I didn't, and went back to my problem. I just NOW got an email that it posted, so I came and found all this help. Thank you!!!

Your account hadn't posted for a while, so had been moved to the AutoModerated group, which we use to catch spammers using dormant accounts (that have weak/leaked passwords). I've moved you back to the Registered group, so future posts shouldn't get auto-moderated.