how can i generate from rust.dylib library and use it in flutter

[cryuhy]

i have a framework RustFramework.xcframework, in ios project,and i want generate some glue code use dart to call rust function in RustFramework,have any method to do this?

[welcome[bot]]

Hi! Thanks for opening your first issue here! :smile:

[fzyzcjy]

flutter_rust_bridge allows your code to be in whatever folder and compiled by whatever way, thus I guess just modify flutter_rust_bridge.yaml config to point to correct folders.

[cryuhy]

flutter_rust_bridge allows your code to be in whatever folder and compiled by whatever way, thus I guess just modify flutter_rust_bridge.yaml config to point to correct folders.

but dart glue generate by flutter_rust_bridge，must need rust source code in rust/src/api/sample.rs ，and sample.rs also compiled in flutter project,but sample.rs already complied in RustFramework.xcframework,so in dont konw how to ignore rust/src/api/sample.rs to be complied

[fzyzcjy]

sample.rs also compiled in flutter project

It seems to be the flutter_rust_bridge_codegen integrate that generates cargokit boilerplate for you, and cargokit does the compilation. In your scenario, I guess you do not need the cargokit boilerplate (since you compile by your own infra), then just do not add it. flutter_rust_bridge will merely generate some .dart and .rs file for you, and will do nothing else.

[cryuhy]

awesome, it works ！，love you，but im facing another question， i see user guide await RustLib.init(externalLibrary: loadMyRustLibraryUsingWhateverMethod()); but how can is assign my framework, full path? ，or name ，my framework is must dynamic? i found my frameworkd is static lib

[fzyzcjy]

Happy to see it works! Just use whatever approach to load your external library. The default loading function https://github.com/fzyzcjy/flutter_rust_bridge/blob/master/frb_dart/lib/src/loader/_io.dart may be a good starting point

[cryuhy]

RedMessageReply  reply = RedMessageReply.fromJson(map);
var mainBundlePath = reply.params?['path'];
ExternalLibrary externalLibrary = ExternalLibrary.open(mainBundlePath, debugInfo: 'im');
await RustLib.init(externalLibrary: externalLibrary);

i got correct rust.dylib path /private/var/containers/Bundle/Application/34396BEE-481A-40AA-8BED-76B59CD8D55E/Runner.app/Frameworks/libsdk.dylib but i got error in this line await RustLib.init(externalLibrary: externalLibrary); error is Invalid argument(s): Invalid argument(s): Failed to lookup symbol 'frb_get_rust_content_hash': dlsym(0xfbb9ad90, frb_get_rust_content_hash): symbol not found how can i fix this error

[fzyzcjy]

It would be great to provide a minimal reproducible sample to debug. Without that, some thoughts: maybe firstly check whether your dylib really has those symbols (by nm/objdump etc)

[cryuhy]

i use nm cmd did not see frb_get_rust_content_hash, frb_get_rust_content_hash symbol look like is contain by flutter_rust_bridge sdk? how can i container this symbol in my dylib, in my rust project i add sdk in my cargo file ![Uploading github.png…]()

[cryuhy]

can you give me email my simple demo to debug has 789mb it is too large.......

[cryuhy]

i call dylib method success, but run flutter_rust_bridge_codgen like this code

#[flutter_rust_bridge::frb(sync)] // Synchronous mode for simplicity of the demo
#[uniffi::export]
pub fn greet(name: String) -> String {
    format!("Hello, {name}!")
}

#[flutter_rust_bridge::frb(init)]
#[uniffi::export]
pub fn init_app() {
    // Default utilities - feel free to customize
    flutter_rust_bridge::setup_default_user_utils();
}

raise error

.cargo/registry/src/index.crates.io-6f17d22bba15001f/flutter_rust_bridge_codegen-2.0.0-dev.32/src/library/utils/logs.rs:52] panicked at /Users/chenrui/.cargo/registry/src/index.crates.io-6f17d22bba15001f/flutter_rust_bridge_codegen-2.0.0-dev.32/src/library/codegen/parser/type_parser/ty.rs:12:61:
called `Result::unwrap()` on an `Err` value: qself "<String>" in "< String as :: uniffi :: Lift < crate :: UniFfiTag > > :: FfiType", and all qself syntax, is unsupported
thread 'main' panicked at /Users/chenrui/.cargo/registry/src/index.crates.io-6f17d22bba15001f/flutter_rust_bridge_codegen-2.0.0-dev.32/src/library/codegen/parser/type_parser/ty.rs:12:61:
called `Result::unwrap()` on an `Err` value: qself "<String>" in "< String as :: uniffi :: Lift < crate :: UniFfiTag > > :: FfiType", and all qself syntax, is unsupported
note: run with `RUST_BACKTRACE=1` environment variable to display a backtrace how can i fixed it

[fzyzcjy]

can you give me email my simple demo to debug has 789mb it is too large.......

Usually the source code itself is enough (no need to upload compiled binaries etc)

i call dylib method success, but run flutter_rust_bridge_codgen like this code

I guess uniffi::export will create something fancy and thus flutter_rust_bridge gets confused. Is there any other ways to use uniffi without macro expansion? Btw, curious why you are using uniffi + flutter_rust_bridge

[cryuhy]

can you give me email my simple demo to debug has 789mb it is too large.......

Usually the source code itself is enough (no need to upload compiled binaries etc)

i call dylib method success, but run flutter_rust_bridge_codgen like this code

I guess uniffi::export will create something fancy and thus flutter_rust_bridge gets confused. Is there any other ways to use uniffi without macro expansion? Btw, curious why you are using uniffi + flutter_rust_bridge

becuase my rust is compiled by cargo swift cmd ，my dylib need both call by flutter and swift directly，if i dont use uniffi::export，dylib can not find symbol such as frb_get_rust_content_hash， but when i use uniffi::export dylib will contain this symbol for example uniffi::export pub fn greet(name: String) -> String { format!("Hello, {name}!") } use outool -tV /my.dylib will see "greet" symbol but without uniffi::export source code like this pub fn greet(name: String) -> String { format!("Hello, {name}!") } use outool -tV /my.dylib did not see "greet" symbol so first source code complied dylib can correct called by flutter second source code complied dylib will crash error is " Failed to lookup symbol "

[fzyzcjy]

my dylib need both call by flutter and swift directly

I see, then this looks pretty reasonable. Then could you please check the expanded uniffi macro to see what is generated? Maybe we can workaround it.

Alternatively, https://mozilla.github.io/uniffi-rs/udl_file_spec.html looks also a possible approach to avoid using uniffi::export

if i dont use uniffi::export，dylib can not find symbol such as frb_get_rust_content_hash

For flutter_rust_bridge, it should find the symbol IMHO, if not it is a bug.

Btw, it would be great to format the code into code blocks for easier reading.

[cryuhy]

my dylib need both call by flutter and swift directly

I see, then this looks pretty reasonable. Then could you please check the expanded uniffi macro to see what is generated? Maybe we can workaround it.

Alternatively, https://mozilla.github.io/uniffi-rs/udl_file_spec.html looks also a possible approach to avoid using uniffi::export

if i dont use uniffi::export，dylib can not find symbol such as frb_get_rust_content_hash

For flutter_rust_bridge, it should find the symbol IMHO, if not it is a bug.

Btw, it would be great to format the code into code blocks for easier reading.

yes use udl may fix this error，but i use anhoter way i write shell to delete uniffi::export when flutter_rust_bridge finished then shell will auto add uniffi::export that works