Failed to load dynamic library (dlopen failed: library libsqlite3.so not found)

[alexobviously]

I've got a flutter app using both sqflite_ffi, with a script that works fine when I run it as pure dart but crashes with this error when I trigger it as part of the flutter app:

I/flutter (18313): [SqfliteFfiException(error, Invalid argument(s): Failed to load dynamic library (dlopen failed: library "/data/data/com.twoplayerchess/lib/libsqlite3.so" not found)} DatabaseException(Invalid argument(s): Failed to load dynamic library (dlopen failed: library "/data/data/com.twoplayerchess/lib/libsqlite3.so" not found)) {}, #0      SqfliteIsolate.handle (package:sqflite_common_ffi/src/isolate.dart:39:9)
I/flutter (18313): <asynchronous suspension>
I/flutter (18313): #1      FfiMethodCallHandler._isolateHandle (package:sqflite_common_ffi/src/database_factory_ffi.dart:54:27)
I/flutter (18313): #2      FfiMethodCallHandler.handleInIsolate (package:sqflite_common_ffi/src/database_factory_ffi.dart:33:26)
I/flutter (18313): #3      databaseFactoryFfiImpl.<anonymous closure> (package:sqflite_common_ffi/src/database_factory_ffi.dart:17:25)
I/flutter (18313): #4      _SqfliteDatabaseFactoryImpl.invokeMethod (package:sqflite_common/src/mixin/factory.dart:20:27)
I/flutter (18313): #5      SqfliteDatabaseMixin.invokeMethod (package:sqflite_common/src/database_mixin.dart:287:15)
I/flutter (18313): #6      SqfliteDatabaseMixin.saf

Flutter doctor -v

[✓] Flutter (Channel stable, 1.20.2, on Mac OS X 10.14.6 18G2022, locale en-GB)
    • Flutter version 1.20.2 at /Users/alex/Developer/flutter
    • Framework revision bbfbf1770c (4 weeks ago), 2020-08-13 08:33:09 -0700
    • Engine revision 9d5b21729f
    • Dart version 2.9.1

 
[✓] Android toolchain - develop for Android devices (Android SDK version 29.0.3)
    • Android SDK at /Users/alex/Library/Android/sdk
    • Platform android-29, build-tools 29.0.3
    • Java binary at: /Applications/Android
      Studio.app/Contents/jre/jdk/Contents/Home/bin/java
    • Java version OpenJDK Runtime Environment (build
      1.8.0_242-release-1644-b3-6222593)
    • All Android licenses accepted.

[✓] Xcode - develop for iOS and macOS (Xcode 11.3.1)
    • Xcode at /Applications/Xcode.app/Contents/Developer
    • Xcode 11.3.1, Build version 11C504
    • CocoaPods version 1.9.1

[✓] Android Studio (version 4.0)
    • Android Studio at /Applications/Android Studio.app/Contents
    • Flutter plugin version 48.0.2
    • Dart plugin version 193.7361
    • Java version OpenJDK Runtime Environment (build
      1.8.0_242-release-1644-b3-6222593)

[!] IntelliJ IDEA Community Edition (version 2020.1)
    • IntelliJ at /Applications/IntelliJ IDEA CE.app
    ✗ Flutter plugin not installed; this adds Flutter specific functionality.
    ✗ Dart plugin not installed; this adds Dart specific functionality.
    • For information about installing plugins, see
      https://flutter.dev/intellij-setup/#installing-the-plugins

[✓] VS Code (version 1.48.2)
    • VS Code at /Applications/Visual Studio Code.app/Contents
    • Flutter extension version 3.14.1

[✓] Connected device (1 available)
    • Android SDK built for x86 (mobile) • emulator-5554 • android-x86 • Android 10
      (API 29) (emulator)

! Doctor found issues in 1 category.

I'm also using the standard sqflite plugin as part of this app for something totally separate. Don't know if that affects anything but that part is running fine. I'm only using sqflite_ffi for this part because it needs to run outside flutter sometimes too and sqflite doesn't support that. I'm not doing anything special when it crashes, just opening a static asset database.

[Aracoix]

same question

[alextekartik]

This part is handled by sqlite3 package. In the README there is a snipped that shows how to bundle libsqlite3.so with your app that you could try.

See simolus3/sqlite3.dart#8

[alextekartik]

Also I'm not sure on which platform you are getting the issue (linux? android?). I recommend using sqflite (not sqflite_common_ffi) on Android

[alexobviously]

Also I'm not sure on which platform you are getting the issue (linux? android?). I recommend using sqflite (not sqflite_common_ffi) on Android

I'm building for android/ios but I also have some tools that needs to run in dart alone, which is why I wasn't just using sqflite (I have a large static db that is only read from the app but I have a dart script to build it).

I have built two separate versions of the sqlite interface now, one using sqflite, but I've run into a different problem - it doesn't seem like it works in an isolate, and that's unfortunately necessary for my application. I've had a bit of a look around here and correct me if I'm wrong but it seems like sqlite doesn't work outside of the main isolate at all?

So I think I need to find a different type of database for this app. I'm trying Hive at the moment but it seems like it suffers from the same problem, so if anyone has any suggestions I'd appreciate them.

[alextekartik]

correct me if I'm wrong but it seems like sqlite doesn't work outside of the main isolate at all?

That's correct. sqflite has its own native threading mechanism and should be used from the main isolate only. (sqflite_common_ffi runs in a separate isolate but must also be used from the main isolate only)

[bksubhuti]

I have a multiplatform app that I'm writing and doing a proof of concept. I have an app that has a prebuilt db, yet most of the samples, simply build the db in code. In android and ios, you have to copy the prebuilt db from the assets folder to the path that the library gives you . The copying is done byte by byte. After that copy is done, one can do the db stuff as expected and as the tutorials show.

So the question is how to do this? Is there an example for a

1. Using an already populated db that has never been used before
2. android/ios (mobile)
3. same code for desktop.. win/linux.

My sample code for proof of concept works with the android OS.
I want it to work with the ffi on linux but there is no code example.
my git repo for such and example is located at: https://github.com/bksubhuti/mydbtest

[alextekartik]

@bksubhuti I don't have an example for your exact situation but you can find:

• a generic solution for opening a database from assets
• a simple app that works on all platforms (desktop/mobile, even linux). You just have to re-create the project.

[bksubhuti]

My repo I posted
above https://github.com/bksubhuti/mydbtest does copy from the assets using the same technique as the first link you posted. Everyone uses the same example which is mostly the same as this example. However that is only for Android & iOS. . I will look at the second link you gave .but I suspect it is done without a pre-populated assets db as the first example used. Perhaps.one does not need to copy a db to the runtime area like mobiles do.

I'm totally new to flutter and just doing a test for proof of concept before we rewrite a Buddhist Pali reading app (tipitaka Pali Projector). So far I'm impressed and pro-flutter. I'll come.back to report later tonight. Using the ffi still on the mobile emulator is different and there an error as reported on this thread.

[alextekartik]

I will look at the second link you gave .but I suspect it is done without a pre-populated assets db

Correct if just show how to use sqflite on linux

Perhaps.one does not need to copy a db to the runtime area like mobiles do.

Correct, the code (to copy the asset database to a writable location) should be similar, you need to copy the asset file somewhere. I guess you could use path_provider to find the proper destination on Desktop.

[bksubhuti]

Well then if I was I was correct as suspected (not from assets). then can you make a small example that opens a single table query from prepopulated database from assets and works on all platforms? I suspect this has never been done before and no example code exist nor has this been tested. It would be required for the ffi library to say "functional" on all platforms. Since I'm one or two weeks into flutter and a few days into SQLite, this would be a difficult task for me.

[alextekartik]

I follow the doc here on how to use sqflite on linux and was able to run your example on linux with very few changes. I created a pull request so you can see the changes made.

can you make a small example that opens a single table query from prepopulated database from assets and works on all platforms?

Hard for me to create an example for all cases unfortunately. I develop and maintain this library in my free time. However examples are welcome!

It would be required for the ffi library to say "functional" on all platforms.

I know the documentation is poor. The notepad example is a way to say "functional" on all platforms. Copying an asset file is not sqflite specific. So maybe you can find more information in flutter docs regarding how to deal with assets: https://flutter.dev/docs/development/ui/assets-and-images

[bksubhuti]

That is excellent. I'm new to GitHub and need to figure out how to do admin for pull req . Not sure what that is It is easier to make you a contributer to the main repo since this is just test stuff anyways. . I'm also part time doing sw dev and a monk full time. I have been away from programming since the 90's. Flutter and even SQLite are well documented compared to other FOSS platforms. But my old days were msvc++ in the 90's . I'm learning now as I try to make free religious reading apps for my own use and others too.

[bksubhuti]

I pulled the new project, but the flutter run -d linux failed.
I did this with another project.. got a similar error in the terminal command window, however, the project worked and ran.
I did a flutter upgrade but it still gave the error and launched the mydb app but did not do a query.
However, your changes did work with the android emulator

There was a note on stackexhange about using AUR instead of snap for flutter install. I hope not.
I did the upgrade, not sure what more to do.

$ flutter run -d linux
Launching lib/main.dart on Linux in debug mode...
/snap/flutter/current/usr/bin/ld: warning: /usr/lib/gcc/x86_64-linux-gnu/10/../../../x86_64-linux-gnu/crt1.o: unsupported GNU_PROPERTY_TYPE (5) type: 0xc0008002
/snap/flutter/current/usr/bin/ld: warning: //lib/x86_64-linux-gnu/libdl.so.2: unsupported GNU_PROPERTY_TYPE (5) type: 0xc0008002
Building Linux application...
Syncing files to device Linux...

[alextekartik]

We are going away from the original issue here sorry. You should first try to build a linux project without sqflite. If necessary you might have to delete the linux folder and re-create the project. If you manage to run and build a linux project without sqflite and fail when adding sqflite, please open a new issue.

[bksubhuti]

I said in the previous that i did build an app without sqlite and got the same error, but it did run. When i did linux build, it ran but hung on the listbuild from the db. I changed the channel from master to stable (and then did flutter upgrade) but it still failed in the same way. However, I trust that you tested in linux, because a couple of generated files popped into the linux folder when I did the pull. Linux is still new as well, so maybe that is the problem. Did you test on Linux? If so, i think , yes this issue is closed.