Add wasm bindings

Cargo.toml

@@ -1,5 +1,5 @@
 [workspace]
-members = ["uniffi-bindgen","walletkit-core", "walletkit"]
+members = ["uniffi-bindgen", "walletkit-core", "walletkit", "wasm"]
 resolver = "2"
 
 [workspace.package]
@@ -8,20 +8,30 @@ license = "MIT"
 edition = "2021"
 authors = ["World Contributors"]
 readme = "./README.md"
-homepage = "https://docs.world.org" # TODO: Update to specific WalletKit page
-rust-version = "1.86" # MSRV
+homepage = "https://docs.world.org"                             # TODO: Update to specific WalletKit page
+rust-version = "1.86"                                           # MSRV
 repository = "https://github.com/worldcoin/walletkit"
 exclude = ["tests/", "uniffi-bindgen/"]
 keywords = ["ZKP", "WorldID", "World", "Identity", "Semaphore"]
 categories = ["api-bindings", "cryptography::cryptocurrencies"]
 
 
 [workspace.dependencies]
-alloy-core = { version = "1", default-features = false, features = ["sol-types"] }
+alloy-core = { version = "1", default-features = false, features = [
+    "sol-types",
+] }
 alloy-primitives = { version = "1", default-features = false }
 walletkit-core = { version = "0.1.8", path = "walletkit-core", default-features = false }
-uniffi = { version = "0.29", features = ["build", "tokio"] }
-world-id-core = { git = "https://github.com/worldcoin/world-id-protocol", rev = "8041ac3", default-features = false, features = ["authenticator"] }
+uniffi = { version = "0.29", default-features = false }
+world-id-core = { path = "../world-id-protocol/crates/core", default-features = false, features = [
+    "authenticator",
+] }
+wasm-bindgen = "0.2"
+wasm-bindgen-futures = "0.4"
+js-sys = "0.3"
+web-sys = { version = "0.3", features = [] }
+serde = { version = "1", features = ["derive"] }
+serde_json = "1"
 
 [profile.release]
 opt-level = 'z' # Optimize for size.

walletkit-core/Cargo.toml

@@ -25,28 +25,48 @@ alloy-core = { workspace = true }
 alloy-primitives = { workspace = true }
 hex = "0.4"
 log = "0.4"
-reqwest = { version = "0.12", default-features = false, features = [
-    "json",
-    "brotli",
-    "rustls-tls",
-] }
 ruint = { version = "1.17", default-features = false, features = [
     "alloc",
     "ark-ff-04",
 ] }
 secrecy = "0.10"
-semaphore-rs = { version = "0.5" }
+# semaphore-rs uses mmap which doesn't compile on wasm; make it optional and gate on semaphore feature.
+semaphore-rs = { version = "0.5", optional = true }
 serde = "1"
 serde_json = "1"
 strum = { version = "0.27", features = ["derive"] }
 subtle = "2"
 thiserror = "2"
-tokio = { version = "1", features = ["sync"] }
-uniffi = { workspace = true, features = ["build", "tokio"] }
 world-id-core = { workspace = true, optional = true }
 
+[target.'cfg(target_arch = "wasm32")'.dependencies]
+reqwest = { version = "0.12", default-features = false, features = ["json"] }
+uniffi = { workspace = true, default-features = false }
+tokio = { version = "1", default-features = false, features = ["sync"] }
+
+[target.'cfg(not(target_arch = "wasm32"))'.dependencies]
+reqwest = { version = "0.12", default-features = false, features = [
+    "json",
+    "brotli",
+    "rustls-tls",
+] }
+uniffi = { workspace = true, features = ["build", "tokio"] }
+tokio = { version = "1", features = [
+    "sync",
+    "macros",
+    "rt",
+    "rt-multi-thread",
+    "time",
+] }
+
 [dev-dependencies]
-alloy = { version = "1", default-features = false, features = ["getrandom", "json", "contract", "node-bindings", "signer-local"] }
+alloy = { version = "1", default-features = false, features = [
+    "getrandom",
+    "json",
+    "contract",
+    "node-bindings",
+    "signer-local",
+] }
 chrono = "0.4.41"
 dotenvy = "0.15.7"
 mockito = "1.6"
@@ -59,7 +79,8 @@ rand = "0.8"
 default = ["common-apps", "semaphore", "v4"]
 common-apps = []
 http-tests = []
-semaphore = ["semaphore-rs/depth_30"]
+# Semaphore proof generation pulls mmap-rs (not wasm-compatible); require explicit opt-in.
+semaphore = ["dep:semaphore-rs", "semaphore-rs/depth_30"]
 v4 = ["world-id-core"]
 
 # Before conventions were introduced for external nullifiers with `app_id` & `action`, raw field elements were used.

walletkit-core/src/authenticator.rs

@@ -9,10 +9,11 @@ use crate::{
 };
 
 /// The Authenticator is the main component with which users interact with the World ID Protocol.
-#[derive(Debug, uniffi::Object)]
+#[derive(Debug)]
+#[cfg_attr(not(target_arch = "wasm32"), derive(uniffi::Object))]
 pub struct Authenticator(CoreAuthenticator);
 
-#[uniffi::export(async_runtime = "tokio")]
+#[cfg_attr(not(target_arch = "wasm32"), uniffi::export(async_runtime = "tokio"))]
 impl Authenticator {
     /// Initializes a new Authenticator from a seed and with SDK defaults.
     ///

walletkit-core/src/credential_type.rs

@@ -20,8 +20,8 @@ use crate::Environment;
     Display,
     Serialize,
     Deserialize,
-    uniffi::Enum,
 )]
+#[cfg_attr(not(target_arch = "wasm32"), derive(uniffi::Enum))]
 #[strum(serialize_all = "snake_case")]
 #[serde(rename_all = "snake_case")]
 pub enum CredentialType {

walletkit-core/src/error.rs

@@ -4,7 +4,8 @@ use thiserror::Error;
 use world_id_core::AuthenticatorError;
 
 /// Error outputs from `WalletKit`
-#[derive(Debug, Error, uniffi::Error)]
+#[derive(Debug, Error)]
+#[cfg_attr(not(target_arch = "wasm32"), derive(uniffi::Error))]
 pub enum WalletKitError {
     /// Invalid input provided (e.g., incorrect length, format, etc.)
     #[error("invalid_input_{attribute}")]
@@ -99,6 +100,7 @@ impl From<reqwest::Error> for WalletKitError {
     }
 }
 
+#[cfg(feature = "semaphore")]
 impl From<semaphore_rs::protocol::ProofError> for WalletKitError {
     fn from(error: semaphore_rs::protocol::ProofError) -> Self {
         Self::ProofGeneration {

walletkit-core/src/lib.rs

@@ -26,7 +26,8 @@ use strum::EnumString;
 /// Each environment uses different sources of truth for the World ID credentials.
 ///
 /// More information on testing for the World ID Protocol can be found in: `https://docs.world.org/world-id/quick-start/testing`
-#[derive(Debug, Clone, PartialEq, Eq, EnumString, uniffi::Enum)]
+#[derive(Debug, Clone, PartialEq, Eq, EnumString)]
+#[cfg_attr(not(target_arch = "wasm32"), derive(uniffi::Enum))]
 #[strum(serialize_all = "lowercase")]
 pub enum Environment {
     /// For testing purposes ONLY.
@@ -58,13 +59,15 @@ pub use authenticator::Authenticator;
 pub(crate) mod defaults;
 
 ////////////////////////////////////////////////////////////////////////////////
-// Legacy modules
+// Legacy modules (require semaphore feature for proof generation)
 ////////////////////////////////////////////////////////////////////////////////
 
 /// Contains all components to interact and use a World ID
+#[cfg(feature = "semaphore")]
 pub mod world_id;
 
 /// This module handles World ID proof generation
+#[cfg(feature = "semaphore")]
 pub mod proof;
 
 /// This module exposes helper functions to interact with common apps & contracts related to the World ID Protocol.
@@ -75,7 +78,10 @@ pub mod common_apps;
 // Private modules
 ////////////////////////////////////////////////////////////////////////////////
 
+#[cfg(feature = "semaphore")]
 mod merkle_tree;
+#[cfg(feature = "semaphore")]
 mod request;
 
+#[cfg(not(target_arch = "wasm32"))]
 uniffi::setup_scaffolding!("walletkit_core");

walletkit-core/src/logger.rs

@@ -42,7 +42,7 @@ use std::sync::{Arc, OnceLock};
 /// ```swift
 /// setupWalletKitLogger() // Call this only once!!!
 /// ```
-#[uniffi::export(with_foreign)]
+#[cfg_attr(not(target_arch = "wasm32"), uniffi::export(with_foreign))]
 pub trait Logger: Sync + Send {
     /// Logs a message at the specified log level.
     ///
@@ -56,7 +56,8 @@ pub trait Logger: Sync + Send {
 /// Enumeration of possible log levels.
 ///
 /// This enum represents the severity levels that can be used when logging messages.
-#[derive(Debug, Clone, uniffi::Enum)]
+#[derive(Debug, Clone)]
+#[cfg_attr(not(target_arch = "wasm32"), derive(uniffi::Enum))]
 pub enum LogLevel {
     /// Designates very low priority, often extremely detailed messages.
     Trace,
@@ -170,7 +171,7 @@ static LOGGER_INSTANCE: OnceLock<Arc<dyn Logger>> = OnceLock::new();
 /// # Note
 ///
 /// If the logger has already been set, this function will print a message and do nothing.
-#[uniffi::export]
+#[cfg_attr(not(target_arch = "wasm32"), uniffi::export)]
 pub fn set_logger(logger: Arc<dyn Logger>) {
     match LOGGER_INSTANCE.set(logger) {
         Ok(()) => (),

walletkit-core/src/u256.rs

@@ -13,10 +13,11 @@ use serde::{Deserialize, Serialize};
 /// Particularly, when sending proof inputs/outputs as JSON on HTTP requests, the values SHOULD
 /// be represented as padded hex strings from Big Endian bytes.
 #[allow(clippy::module_name_repetitions)]
-#[derive(Debug, PartialEq, Eq, Clone, Copy, uniffi::Object)]
+#[derive(Debug, PartialEq, Eq, Clone, Copy)]
+#[cfg_attr(not(target_arch = "wasm32"), derive(uniffi::Object))]
 pub struct U256Wrapper(pub U256);
 
-#[uniffi::export]
+#[cfg_attr(not(target_arch = "wasm32"), uniffi::export)]
 impl U256Wrapper {
     /// Outputs a hex string representation of the `U256` value padded to 32 bytes (plus two bytes for the `0x` prefix).
     #[must_use]
@@ -48,7 +49,7 @@ impl U256Wrapper {
     ///
     /// Logically this will only support values up to 64 bits. For larger values a different initialization should be used.
     #[must_use]
-    #[uniffi::constructor]
+    #[cfg_attr(not(target_arch = "wasm32"), uniffi::constructor)]
     pub fn from_u64(value: u64) -> Self {
         Self(U256::from(value))
     }
@@ -57,7 +58,7 @@ impl U256Wrapper {
     ///
     /// Logically this will only support values up to 32 bits. For larger values a different initialization should be used.
     #[must_use]
-    #[uniffi::constructor]
+    #[cfg_attr(not(target_arch = "wasm32"), uniffi::constructor)]
     pub fn from_u32(value: u32) -> Self {
         Self(U256::from(value))
     }
@@ -69,7 +70,7 @@ impl U256Wrapper {
     /// # Errors
     ///
     /// Will return an `Error::InvalidNumber` if the input is not a valid `U256` value.
-    #[uniffi::constructor]
+    #[cfg_attr(not(target_arch = "wasm32"), uniffi::constructor)]
     pub fn from_limbs(limbs: Vec<u64>) -> Result<Self, WalletKitError> {
         let limbs = limbs
             .try_into()

wasm/Cargo.toml

@@ -0,0 +1,27 @@
+[package]
+name = "walletkit-wasm"
+version.workspace = true
+edition.workspace = true
+license.workspace = true
+repository.workspace = true
+authors.workspace = true
+description = "WASM bindings for WalletKit"
+
+[package.metadata.wasm-pack.profile.release]
+wasm-opt = false
+
+[lib]
+crate-type = ["cdylib", "rlib"]
+
+[dependencies]
+# Disable semaphore to avoid mmap-rs (not wasm-compatible); only enable v4 authenticator.
+walletkit-core = { path = "../walletkit-core", default-features = false, features = [
+    "v4",
+] }
+wasm-bindgen = { workspace = true }
+wasm-bindgen-futures = { workspace = true }
+js-sys = { workspace = true }
+web-sys = { workspace = true }
+serde = { workspace = true }
+serde_json = { workspace = true }
+serde-wasm-bindgen = "0.6"

wasm/README.md

@@ -0,0 +1,32 @@
+# WalletKit WASM bindings
+
+## Builds
+
+Run the helper scripts from the workspace root (they forward additional arguments to `wasm-pack`):
+
+```bash
+./walletkit/wasm/scripts/build-web.sh      # Builds for browsers
+./walletkit/wasm/scripts/build-node.sh     # Builds for Node.js (ESM + CJS)
+```
+
+Both scripts output artifacts to `walletkit/wasm/pkg/`.
+
+## Usage sketch
+
+```ts
+import init, { Authenticator, Environment } from "./pkg/walletkit_wasm.js";
+import { readFile } from "node:fs/promises";
+
+const wasm = await readFile("./pkg/walletkit_wasm_bg.wasm");
+await init(wasm);
+
+const seed = new Uint8Array(32); // placeholder seed
+const authenticator = await Authenticator.initWithDefaults(
+  seed,
+  "https://rpc.example.com",
+  Environment.Staging()
+);
+
+console.log(authenticator.onchainAddress());
+console.log(await authenticator.getPackedAccountIndexRemote()); // -> bigint
+```

wasm/scripts/build-node.sh

@@ -0,0 +1,7 @@
+#!/usr/bin/env bash
+set -euo pipefail
+
+SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
+CRATE_DIR="$(cd "${SCRIPT_DIR}/.." && pwd)"
+
+wasm-pack build "${CRATE_DIR}" --release --target nodejs "$@"

wasm/scripts/build-web.sh

@@ -0,0 +1,7 @@
+#!/usr/bin/env bash
+set -euo pipefail
+
+SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
+CRATE_DIR="$(cd "${SCRIPT_DIR}/.." && pwd)"
+
+wasm-pack build "${CRATE_DIR}" --release --target web "$@"