Which WASM runtime does it work with?

[kulak]

I tried to deploy basic application based on letpos-tutorial in docs.

Build

trunk build --all-features
cd dist
wasmedge leptos-tutorial-b66b70904785527b_bg.wasm

Run on wasmedge

cd dist
wasmedge leptos-tutorial-b66b70904785527b_bg.wasm

Alternative build produces the same result with trunk build.

Output:

[2023-03-01 21:28:07.964] [error] instantiation failed: unknown import, Code: 0x62
[2023-03-01 21:28:07.964] [error]     When linking module: "wbg" , function name: "__wbindgen_object_clone_ref"
[2023-03-01 21:28:07.964] [error]     At AST node: import description
[2023-03-01 21:28:07.964] [error]     At AST node: import section
[2023-03-01 21:28:07.964] [error]     At AST node: module

Run on wasmtime

wasmtime leptos-tutorial-b66b70904785527b_bg.wasm
Error: failed to run main module `leptos-tutorial-b66b70904785527b_bg.wasm`

Caused by:
    0: failed to instantiate "leptos-tutorial-b66b70904785527b_bg.wasm"
    1: unknown import: `wbg::__wbindgen_object_clone_ref` has not been defined

Works

trunk serve --open works just fine.

[kulak]

I think I am completely wrong here. At least the tutorial part is meant to be executed by the browser.

[gbj]

Right, everything in the tutorial so far is for client-side rendering in the browser.

You can do server-side rendering with native binaries with Leptos very easily.

You can also do server-side rendering in WASM runtimes like run within V8 (Cloudflare Workers, Deno, etc.)

You can also do server-side rendering in wasm32-wasi environments, depending on the environment, with some additional configuration that has to do with the interaction between wasm-bindgen and wasm32-wasi targets that don't exist in a JavaScript world. For example, in wasmtime you can add a --trap-unknown-imports flag that prevents the panic you got. I've never seen wasmedge before so I don't know about that.