Add wasm32/web browser support to the Rust SDK

crates/codegen/src/rust.rs

@@ -1645,10 +1645,11 @@ impl __sdk::InModule for RemoteTables {{
 /// You must explicitly advance the connection by calling any one of:
 ///
 /// - [`DbConnection::frame_tick`].
-/// - [`DbConnection::run_threaded`].
+#[cfg_attr(not(target_arch = \"wasm32\"), doc = \"- [`DbConnection::run_threaded`].\")]
+#[cfg_attr(target_arch = \"wasm32\", doc = \"- [`DbConnection::run_background_task`].\")]
 /// - [`DbConnection::run_async`].
 /// - [`DbConnection::advance_one_message`].
-/// - [`DbConnection::advance_one_message_blocking`].
+#[cfg_attr(not(target_arch =  \"wasm32\"), doc = \"- [`DbConnection::advance_one_message_blocking`].\")]
 /// - [`DbConnection::advance_one_message_async`].
 ///
 /// Which of these methods you should call depends on the specific needs of your application,
@@ -1746,6 +1747,7 @@ impl DbConnection {{
     /// This is a low-level primitive exposed for power users who need significant control over scheduling.
     /// Most applications should call [`Self::run_threaded`] to spawn a thread
     /// which advances the connection automatically.
+    #[cfg(not(target_arch = \"wasm32\"))]
     pub fn advance_one_message_blocking(&self) -> __sdk::Result<()> {{
         self.imp.advance_one_message_blocking()
     }}
@@ -1771,10 +1773,17 @@ impl DbConnection {{
     }}
 
     /// Spawn a thread which processes WebSocket messages as they are received.
+    #[cfg(not(target_arch = \"wasm32\"))]
     pub fn run_threaded(&self) -> std::thread::JoinHandle<()> {{
         self.imp.run_threaded()
     }}
 
+    /// Spawn a background task which processes WebSocket messages as they are received.
+    #[cfg(target_arch = \"wasm32\")]
+    pub fn run_background_task(&self) {{
+        self.imp.run_background_task()
+    }}
+
     /// Run an `async` loop which processes WebSocket messages when polled.
     pub async fn run_async(&self) -> __sdk::Result<()> {{
         self.imp.run_async().await

crates/codegen/tests/snapshots/codegen__codegen_rust.snap

@@ -1390,10 +1390,11 @@ impl __sdk::InModule for RemoteTables {
 /// You must explicitly advance the connection by calling any one of:
 ///
 /// - [`DbConnection::frame_tick`].
-/// - [`DbConnection::run_threaded`].
+#[cfg_attr(not(target_arch = "wasm32"), doc = "- [`DbConnection::run_threaded`].")]
+#[cfg_attr(target_arch = "wasm32", doc = "- [`DbConnection::run_background_task`].")]
 /// - [`DbConnection::run_async`].
 /// - [`DbConnection::advance_one_message`].
-/// - [`DbConnection::advance_one_message_blocking`].
+#[cfg_attr(not(target_arch =  "wasm32"), doc = "- [`DbConnection::advance_one_message_blocking`].")]
 /// - [`DbConnection::advance_one_message_async`].
 ///
 /// Which of these methods you should call depends on the specific needs of your application,
@@ -1491,6 +1492,7 @@ impl DbConnection {
     /// This is a low-level primitive exposed for power users who need significant control over scheduling.
     /// Most applications should call [`Self::run_threaded`] to spawn a thread
     /// which advances the connection automatically.
+    #[cfg(not(target_arch = "wasm32"))]
     pub fn advance_one_message_blocking(&self) -> __sdk::Result<()> {
         self.imp.advance_one_message_blocking()
     }
@@ -1516,10 +1518,17 @@ impl DbConnection {
     }
 
     /// Spawn a thread which processes WebSocket messages as they are received.
+    #[cfg(not(target_arch = "wasm32"))]
     pub fn run_threaded(&self) -> std::thread::JoinHandle<()> {
         self.imp.run_threaded()
     }
 
+    /// Spawn a background task which processes WebSocket messages as they are received.
+    #[cfg(target_arch = "wasm32")]
+    pub fn run_background_task(&self) {
+        self.imp.run_background_task()
+    }
+
     /// Run an `async` loop which processes WebSocket messages when polled.
     pub async fn run_async(&self) -> __sdk::Result<()> {
         self.imp.run_async().await

crates/sql-parser/src/parser/mod.rs

@@ -209,7 +209,9 @@ pub(crate) fn parse_proj(expr: Expr) -> SqlParseResult<ProjectExpr> {
 
 // These types determine the size of [`parse_expr`]'s stack frame.
 // Changing their sizes will require updating the recursion limit to avoid stack overflows.
+#[cfg(target_pointer_width = "64")]
 const _: () = assert!(size_of::<Expr>() == 168);
+#[cfg(target_pointer_width = "64")]
 const _: () = assert!(size_of::<SqlParseResult<SqlExpr>>() == 40);
 
 /// Parse a scalar expression

sdks/rust/Cargo.toml

@@ -9,7 +9,20 @@ rust-version.workspace = true
 # See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
 
 [features]
+default = []
 allow_loopback_http_for_tests = ["spacetimedb-testing/allow_loopback_http_for_tests"]
+web = [
+    "dep:getrandom",
+    "dep:gloo-console",
+    "dep:gloo-net",
+    "dep:gloo-storage",
+    "dep:gloo-utils",
+    "dep:js-sys",
+    "dep:tokio-tungstenite-wasm",
+    "dep:wasm-bindgen",
+    "dep:wasm-bindgen-futures",
+    "dep:web-sys",
+]
 
 [dependencies]
 spacetimedb-data-structures.workspace = true
@@ -28,12 +41,25 @@ bytes.workspace = true
 flate2.workspace = true
 futures.workspace = true
 futures-channel.workspace = true
-home.workspace = true
 http.workspace = true
 log.workspace = true
 once_cell.workspace = true
 prometheus.workspace = true
 rand.workspace = true
+
+getrandom = { version = "0.3.4", features = ["wasm_js"], optional = true }
+gloo-console = { version = "0.3.0", optional = true }
+gloo-net = { version = "0.6.0", optional = true }
+gloo-storage = { version = "0.3.0", optional = true }
+gloo-utils = { version = "0.2.0", optional = true }
+js-sys = { version = "0.3", optional = true }
+tokio-tungstenite-wasm = { version = "0.6.0", optional = true }
+wasm-bindgen = { version = "0.2.100", optional = true }
+wasm-bindgen-futures = { version = "0.4.45", optional = true }
+web-sys = { version = "0.3.77", features = ["HtmlDocument"], optional = true }
+
+[target.'cfg(not(target_arch = "wasm32"))'.dependencies]
+home.workspace = true
 tokio.workspace = true
 tokio-tungstenite.workspace = true