[WASM] "UnknownImport" when WASM is compiled from crates that declare external dependencies

[captainfelar]

Hi all,
Just started learning rust and wasm not too long ago so feel free to challenge the premise of this question if what I am doing is unreasonable to begin with.

As titled, I am running into an UnknownImport error when trying to invoke a exported function from a WASM module that is compiled from a crate that declares external dependency.

I have a WASM module that is compiled using wasm-pack build from the following crate:
src/lib.rs:

use random_number::random;

#[no_mangle]
pub fn add_one(operand: i32) -> i32 {
    let n: i32 = random!();
    operand + n
}

Cargo.toml:

[package]
name = "ttt"
version = "0.1.0"
edition = "2021"

[lib]
crate-type = ["cdylib", "lib"]

[dependencies]
wasm-bindgen = "0.2"
random-number = "0.1.7"
getrandom = { version = "0.2", features = ["js"] }

The directory of crate/pkg/ looks like this after running wasm-pack build:

pkg
├── package.json
├── ttt.d.ts
├── ttt.js
├── ttt_bg.js
├── ttt_bg.wasm
└── ttt_bg.wasm.d.ts

Then I tried invoking this add_one function from another crate, the main function of which looks like the following:

use std::error;

use wasmer::{imports, wat2wasm, Instance, Module, NativeFunc, Store};

fn main() -> Result<(), Box<dyn error::Error>> {
    let wasm_bytes = std::fs::read(".../ttt/pkg/ttt_bg.wasm")?;

    let store = Store::default();
    let module = Module::new(&store, wasm_bytes)?;

    let import_object = imports! {};
    let instance = Instance::new(&module, &import_object)?;

    let add_one: NativeFunc<i32, i32> = instance.exports.get_function("add_one")?.native()?;

    println!("calling add one func...");
    let result = add_one.call(2)?;
    println!("The reuslt is: {}", result);
    Ok(())
}

Upon running, I get the following error:

Error: Link(Import("./ttt_bg.js", "__wbg_randomFillSync_91e2b39becca6147", UnknownImport(Function(FunctionType { params: [I32, I32, I32], results: [] }))))

This looks like it's complaining about an indirect dependency not being accessible when the WASM export function is invoked. Am I correct in that? If so, what is the proper way of exporting the function? Or am I compiling the WASM wrong?

Thanks a lot in advance.