MySQL driver detected but not loading on MacOS

artwaw

@juneleung Like @SGaist said. It is old and well know problem (I really thought addressed by now) that the plugin links to Postgres installation, somewhere in /Application/Postgres.app/[...]/libpq.5.dylib and in order to deploy the program properly one has to dabble and relink. I got annoyed and bored and semiautomated the deployment as above (I also wrote myself some script tools for signing and notarisation, because lack of integration is prevalent on macOS).

Nonetheless - once you get hang on the particular quirks like this one, deploying on macOS is a relative breeze.

juneleung

@artwaw @SGaist

Hi, I use these cmd :

cp /Applications/Postgres.app/Contents/Versions/14/lib/libpq.5.14.dylib /Users/test/Build/build-test-Desktop_Qt_5_15_2_clang_64bit-Release/test.app/Contents/Frameworks/

install_name_tool -change /Applications/Postgres.app/Contents/Versions/14/lib/libpq.5.dylib @executable_path/../Frameworks/libpq.5.14.dylib test/Contents/PlugIns/sqldrivers**/libqsqlpsql.dylib**

install_name_tool -change libpq.5.dylib @executable_path/../Frameworks/libpq.5.14.dylib test.app/Contents/MacOS/test

but an error with I don't have the libqsqlpsql.dylib in sqldrivers folder, and i can't found it in Applications/Postgres.app/Contents/Versions/14/lib/, where to find libqsqlpsql.dylib or how to make it generated automaticly by qt?

SGaist

Might be a silly question but are you using the SQL module in your test app ?

juneleung

@SGaist yes i have add sql in qt.

QT += sql

QSqlDatabase db = QSqlDatabase::addDatabase("QPSQL");

The release package installed in local Macbook can open and link to sqldatabase, but move to another mac will get wrong driver.

Does I miss any steps when release packages?

artwaw

@juneleung said in MySQL driver detected but not loading on MacOS:

I don't have the libqsqlpsql.dylib in sqldrivers folder, and i can't found it in Applications/Postgres.app/Contents/Versions/14/lib/, where to find libqsqlpsql.dylib or how to make it generated automaticly by qt?

That what's macdeployqt should do, if memory serves. Important - can't my be with option App Store compatible. It is Qt plugin, should be deployed.

juneleung

@artwaw said in MySQL driver detected but not loading on MacOS:

That what's macdeployqt should do, if memory serves. Important - can't my with option App Store compatible. It is Qt plugin, should be deployed.

my macdeployqt step is :
macdeployqt /Users/test/Build/build-test-Desktop_Qt_5_15_2_clang_64bit-Release/test.app -dmg

any args should added to generate libqsqlpsql.dylib? or any step to setup at release mode?
Thanks!

artwaw

@juneleung Pls check your package under path:

ls test.app/Contents/PlugIns/sqldrivers
libqsqlite.dylib	libqsqlodbc.dylib	libqsqlpsql.dylib

That's how it should be after the deploy.
You can pass verbose=2 to have more data on how deployment goes (I recommend together with overwrite option, this way you'll be able to see every copied file). Caution, this would be very verbose.

juneleung

@artwaw
Thanks for your guide and I have generated the dylib successfully. :)

in the /Applications/Postgres.app/Contents/Versions/14/lib/, my libpq.5.dylib looks is an alias, so i copy the libpq.5.14.dylib to /Users/test/Build/build-GiraffeL-Desktop_Qt_5_15_2_clang_64bit-Release/test.app/Contents/Frameworks/libpq.5.14.dylib, is it correct to copy libpq.5.14.dylib or I should copy the libpq.5.dylib alias file .

and before running with :

cp /Applications/Postgres.app/Contents/Versions/14/lib/libpq.5.14.dylib /Users/test/Build/build-test-Desktop_Qt_5_15_2_clang_64bit-Release/test.app/Contents/Frameworks/

install_name_tool -change /Applications/Postgres.app/Contents/Versions/9.6/lib/libpq.5.dylib @executable_path/../Frameworks/libpq.5.14.dylib /Users/test/Build/build-test-Desktop_Qt_5_15_2_clang_64bit-Release/test.app/Contents/PlugIns/sqldrivers/libqsqlpsql.dylib

**install_name_tool -change libpq.5.dylib @executable_path/../Frameworks/libpq.5.14.dylib /Users/test/Build/build-test-Desktop_Qt_5_15_2_clang_64bit-Release/test.app/Contents/MacOS/test**

I use otool to check test.app/Contents/MacOS/test

otool -L test.app/Contents/MacOS/test

but it looks don't have the libpq.5.dylib in the print list.
is it correct to install_name_tool the libpq.5.dylib path for the test.app/Contents/MacOS/test? or another file?

artwaw

I used Contents/Frameworks path as it seems to be aligned with what macOS is expecting.
if you look at my example deploy script above you'll see that I copy libpq* files there.
Then install_name_tool of course.

If you check otool (and my script) you'll see exactly what needs to linked to what.

SGaist

@artwaw is correct, the application bundle has rules with regards to what goes where. See the Apple documentation.

artwaw

@SGaist Yes. I forgot to link this, thank you.

juneleung

@artwaw

Sorry, maybe I didn't explain clearly.

I have copied the libpq.5.dylib to the framework folder,

In your previous code

install_name_tool -change libpq.5.dylib @executable_path/../Frameworks/libpq.5.dylib appName.app/Contents/MacOS/appName

it looks like changing the link path in the app file, is this pointing to the app? Or point to another file? Cause I checked the app file (test.app/Contents/MacOS/test) by otool, but in the printed link list, I don't see any information about libpq.5 .dylib part, is this normal?

because there is no part of libpq.5.dylib, so I modified install_name_tool seems doesn't work either?

SGaist

As already written, it's the plugin itself that you have to update. The application does not link nor care about libpsql.

juneleung

@SGaist and @artwaw

Thanks for your patient guidance and finally I solve this issue. The reason happened cause I don't copy all dylib and relink them.

also this link help me to find other dylib which needed, hope this will help other guys who also face this problem.
https://bugreports.qt.io/browse/QTBUG-85500

:D

Thanks again!!