wasm-bindgen setup

.gitignore

@@ -7,4 +7,6 @@
 cert.csr
 cert.der
 /firedbg
-.vscode/ltex.*
+.vscode/ltex.*
+pkg/
+wasm-pack.log

.vscode/settings.json

@@ -1,4 +1,14 @@
 {
 	"markiscodecoverage.searchCriteria": ".coverage/lcov*.info",
-	"rust-analyzer.cargo.features": ["types", "reqwest", "gateway", "serde"]
+	// "rust-analyzer.cargo.features": ["types", "reqwest", "gateway", "serde"]
+	"rust-analyzer.cargo.features": [
+		"_wasm_bindgen",
+		"wasm",
+		"types",
+		"reqwest",
+		"gateway",
+		"serde"
+	],
+	"rust-analyzer.cargo.noDefaultFeatures": true,
+	"rust-analyzer.cargo.target": "wasm32-unknown-unknown"
 }

Cargo.toml

@@ -8,7 +8,7 @@ repository = "https://github.com/polyphony-chat/polyproto"
 rust-version = "1.85.0"
 
 [lib]
-crate-type = ["rlib", "cdylib", "staticlib"]
+crate-type = ["cdylib", "rlib"]
 
 [features]
 default = ["types", "serde", "gateway", "tokio/net"]
@@ -20,6 +20,8 @@ serde = ["dep:serde", "serde_json", "serde_with", "url/serde"]
 serde_with = ["dep:serde_with"]
 serde_json = ["dep:serde_json"]
 gateway = ["serde", "types"]
+_wasm_bindgen = ["wasm", "dep:wasm-bindgen", "dep:js-sys", "dep:wee_alloc"]
+__no_wee_alloc = []
 
 [dependencies]
 der = { version = "0.7.9", features = ["pem"] }
@@ -50,6 +52,11 @@ futures-util = "0.3.31"
 urlencoding = "2.1.3"
 ws_stream_wasm = { version = "*", optional = true }
 
+[target.'cfg(target_arch = "wasm32")'.dependencies]
+wasm-bindgen = { version = "0.2.100", optional = true }
+js-sys = { version = "0.3.77", optional = true }
+wee_alloc = { version = "0.4.5", optional = true }
+
 [target.'cfg(not(target_arch = "wasm32"))'.dependencies]
 rustls = "0.23.25"
 tokio-tungstenite = { version = "0.26.2", features = [
@@ -73,7 +80,18 @@ httptest = "0.16.3"
 
 [target.'cfg(target_arch = "wasm32")'.dev-dependencies]
 wasm-bindgen-test = "0.3.50"
-wasm-bindgen = "0.2.100"
+# The `console_error_panic_hook` crate provides better debugging of panics by
+# logging them with `console.error`. This is great for development, but requires
+# all the `std::fmt` and `std::panicking` infrastructure, so isn't great for
+# code size when deploying.
+console_error_panic_hook = { version = "0.1.7" }
+
+[target.'cfg(target_arch = "wasm32")'.release]
+# Tell `rustc` to optimize for small code size.
+opt-level = "s"
+lto = true
+codegen-units = 1
+panic = "abort"
 
 [lints.rust]
 unexpected_cfgs = { level = "warn", check-cfg = ['cfg(tarpaulin_include)'] }

headaches.md

@@ -0,0 +1,8 @@
+# Headaches involving `wasm-bindgen` and overall Rust ⇾ TS/JS bindgen
+
+- `wasm-bindgen` does not support traits, or struct generics with trait bounds like `struct X<S: TraitImplementer>`
+- Crates like `ts_rs` might help but would require a more complex build process to assemble a finished TS/JS project
+- Worst case: Manually write JS/TS code to bridge the things unsupported by other bindgen libs
+  - Would be immensely painful
+- Other idea: LOADS of handwritten wrappers for Rust functions, also written in Rust but `wasm-bindgen` compatible.
+- For traits like signature, we need to make an extremely generic impl that can be somehow instantiated from js/ts

scripts/wasm-pack-helper

@@ -0,0 +1,40 @@
+#!/bin/bash
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at https://mozilla.org/MPL/2.0/.
+
+# check number of arguments
+if [ "$#" -lt 1 ] || [ "$#" -gt 2 ]; then
+    echo "Error: Invalid number of arguments. Usage: $0 <build|pack|publish> [release|debug]"
+    exit 1
+fi
+
+command=$1
+mode=${2:-"debug"}
+
+# validate if arg #1 is valid
+if [[ "$command" != "build" && "$command" != "pack" && "$command" != "publish" ]]; then
+    echo "Error: First argument must be one of 'build', 'pack', or 'publish'."
+    exit 1
+fi
+
+# same for arg #2
+if [[ "$mode" != "release" && "$mode" != "debug" ]]; then
+    echo "Error: Second argument must be either 'release' or 'debug'. Defaulting to 'debug'."
+    mode="debug"
+fi
+
+# wasm-pack check
+if ! command -v wasm-pack &> /dev/null; then
+    # prompt user to install wasm-pack
+    read -p "wasm-pack could not be found. Do you want to install it? (y/n): " install_wasm_pack
+    if [[ "$install_wasm_pack" == [Yy]* ]]; then
+        cargo install wasm-pack --force
+    else
+        echo "Error: wasm-pack is required for this script."
+        exit 1
+    fi
+fi
+
+# Execute the wasm-pack command
+wasm-pack $command --$mode --no-default-features --features=wasm,reqwest,serde,types,_wasm_bindgen

src/key.rs

@@ -36,5 +36,7 @@ pub trait PublicKey<S: Signature>: PartialEq + Eq + Clone {
         S::algorithm_identifier()
     }
     /// Creates a new [Self] from a [PublicKeyInfo].
-    fn try_from_public_key_info(public_key_info: PublicKeyInfo) -> Result<Self, CertificateConversionError>;
+    fn try_from_public_key_info(
+        public_key_info: PublicKeyInfo,
+    ) -> Result<Self, CertificateConversionError>;
 }

src/lib.rs

@@ -139,6 +139,14 @@ of this project.
     clippy::todo
 )]
 
+#[cfg(all(
+    target_arch = "wasm32",
+    feature = "_wasm_bindgen",
+    not(feature = "__no_wee_alloc")
+))]
+#[global_allocator]
+static ALLOC: wee_alloc::WeeAlloc = wee_alloc::WeeAlloc::INIT;
+
 /// The OID for the `domainComponent` RDN
 pub const OID_RDN_DOMAIN_COMPONENT: &str = "0.9.2342.19200300.100.1.25";
 /// The OID for the `commonName` RDN
@@ -168,6 +176,10 @@ pub mod signature;
 /// Types used in polyproto and the polyproto HTTP/REST APIs
 pub mod types;
 
+#[cfg(all(target_arch = "wasm32", feature = "_wasm_bindgen"))]
+/// 🚧 Under construction! 👷 Module for exporting polyproto to JS/TS.
+pub mod wasm_bindgen;
+
 mod constraints;
 
 pub use der;

src/wasm_bindgen/errors.rs

@@ -0,0 +1,11 @@
+// This Source Code Form is subject to the terms of the Mozilla Public
+// License, v. 2.0. If a copy of the MPL was not distributed with this
+// file, You can obtain one at https://mozilla.org/MPL/2.0/.
+
+use wasm_bindgen::prelude::*;
+
+#[derive(Debug, Clone, Copy)]
+#[wasm_bindgen(js_name = "PolyprotoError")]
+pub enum JsConstraintError {
+    InvalidInput,
+}

src/wasm_bindgen/mod.rs

@@ -0,0 +1,8 @@
+// This Source Code Form is subject to the terms of the Mozilla Public
+// License, v. 2.0. If a copy of the MPL was not distributed with this
+// file, You can obtain one at https://mozilla.org/MPL/2.0/.
+
+pub mod errors;
+pub mod types;
+
+mod utils;

src/wasm_bindgen/types.rs

@@ -0,0 +1,40 @@
+// This Source Code Form is subject to the terms of the Mozilla Public
+// License, v. 2.0. If a copy of the MPL was not distributed with this
+// file, You can obtain one at https://mozilla.org/MPL/2.0/.
+
+use crate::types::DomainName as RDomainName;
+use crate::types::FederationId as RFederationId;
+use wasm_bindgen::prelude::*;
+
+use super::errors::JsConstraintError;
+
+#[derive(Clone, Debug)]
+#[wasm_bindgen(inspectable)]
+/// A `FederationId` is a globally unique identifier for an actor in the context of polyproto.
+pub struct FederationId {
+    #[wasm_bindgen(skip)]
+    _inner: RFederationId,
+}
+
+#[wasm_bindgen]
+impl FederationId {
+    #[wasm_bindgen(constructor)]
+    /// Validates input, then creates a new `FederationId`. Throws an error if input validation fails.
+    pub fn new(id: &str) -> Result<FederationId, JsConstraintError> {
+        Ok(FederationId {
+            _inner: RFederationId::new(id).map_err(|_| JsConstraintError::InvalidInput)?,
+        })
+    }
+
+    #[wasm_bindgen(js_name = "toJSON")]
+    pub fn js_to_json(&self) -> String {
+        self._inner.to_string()
+    }
+}
+
+#[derive(Debug, Clone)]
+#[wasm_bindgen(inspectable)]
+pub struct DomainName {
+    #[wasm_bindgen(skip)]
+    _inner: RDomainName,
+}

src/wasm_bindgen/utils.rs

@@ -0,0 +1,14 @@
+// This Source Code Form is subject to the terms of the Mozilla Public
+// License, v. 2.0. If a copy of the MPL was not distributed with this
+// file, You can obtain one at https://mozilla.org/MPL/2.0/.
+
+pub fn set_panic_hook() {
+    // When the `console_error_panic_hook` feature is enabled, we can call the
+    // `set_panic_hook` function at least once during initialization, and then
+    // we will get better error messages if our code ever panics.
+    //
+    // For more details see
+    // https://github.com/rustwasm/console_error_panic_hook#readme
+    #[cfg(feature = "console_error_panic_hook")]
+    console_error_panic_hook::set_once();
+}