feat: wasm support (#390)

* feat: partial wasm32 support

* make compile for wasm32

* feat: att async-trait attr

* make compatible with wasm

* add type alias for archs

* rustfmt

* add wasm ci

* make compile with wasm-pack test

* make compile with wasm-pack test

* make compile with wasm-pack test

* make compile with wasm-pack test

* ci: disable wasmpack

* feat: use wasm timer delay

* feat: add wasm provider

* rustfmt

* misc refactor

* add wasm example

* make example a directory

* untrack error log

* move profile to root

* fix unused imports

* ci: enable wasm-pack test

* style: unify websocket implementations

* fix: typos

* fix: make policy compatible with wasm target

* chore: do not include ethers-wasm example as top level workspace member

* chore: modify wasm32 dependencies

* chore: make note about getrandom

Co-authored-by: Georgios Konstantopoulos <me@gakonst.com>

.github/workflows/ci.yml

@@ -115,3 +115,47 @@ jobs:
         run: cargo fmt --all -- --check
       - name: cargo clippy
         run: cargo clippy -- -D warnings
+
+  wasm:
+    name: WASM
+    runs-on: ubuntu-latest
+
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v1
+      - name: Install node
+        uses: actions/setup-node@v1
+        with:
+          node-version: 10
+      - name: Install rust
+        uses: actions-rs/toolchain@v1
+        with:
+          toolchain: stable
+          target: wasm32-unknown-unknown
+          profile: minimal
+          override: true
+
+      - name: Check
+        uses: actions-rs/cargo@v1
+        with:
+          command: check
+          args: --target wasm32-unknown-unknown
+
+      - name: Launch Ganache
+        run: |
+          cd examples/ethers-wasm
+          npm install
+          npm run ganache &
+
+      - name: Install wasm-pack
+        run: curl https://rustwasm.github.io/wasm-pack/installer/init.sh -sSf | sh
+
+      - name: Wasm-pack test firefox
+        run: |
+          cd examples/ethers-wasm
+          wasm-pack test --headless --firefox
+
+      - name: Wasm-pack test chrome
+        run: |
+          cd examples/ethers-wasm
+          wasm-pack test --headless --chrome

Cargo.lock

@@ -111,6 +111,17 @@ dependencies = [
  "syn",
 ]
 
+[[package]]
+name = "async_io_stream"
+version = "0.3.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "541b3487bf601cf3a63dfba621d6d0252611f120aaf27b198f018c0e1714f0df"
+dependencies = [
+ "futures",
+ "pharos",
+ "rustc_version 0.3.3",
+]
+
 [[package]]
 name = "auto_impl"
 version = "0.4.1"
@@ -144,6 +155,12 @@ dependencies = [
  "rustc-demangle",
 ]
 
+[[package]]
+name = "base-x"
+version = "0.2.8"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "a4521f3e3d031370679b3b140beb36dfe4801b09ac77e30c61941f97df3ef28b"
+
 [[package]]
 name = "base58"
 version = "0.1.0"
@@ -355,7 +372,7 @@ checksum = "c297bd3135f558552f99a0daa180876984ea2c4ffa7470314540dff8c654109a"
 dependencies = [
  "camino",
  "cargo-platform",
- "semver",
+ "semver 1.0.4",
  "serde",
  "serde_json",
 ]
@@ -400,7 +417,7 @@ dependencies = [
  "num-integer",
  "num-traits",
  "serde",
- "time",
+ "time 0.1.43",
  "winapi",
 ]
 
@@ -509,6 +526,12 @@ version = "0.6.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "44c32f031ea41b4291d695026c023b95d59db2d8a2c7640800ed56bc8f510f22"
 
+[[package]]
+name = "const_fn"
+version = "0.4.8"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "f92cfa0fd5690b3cf8c1ef2cabbd9b7ef22fa53cf5e1f92b05103f6d5d1cf6e7"
+
 [[package]]
 name = "constant_time_eq"
 version = "0.1.5"
@@ -676,6 +699,12 @@ dependencies = [
  "winapi",
 ]
 
+[[package]]
+name = "discard"
+version = "1.0.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "212d0f5754cb6769937f4501cc0e67f4f4483c8d2c3e1e922ee9edbe4ab4c7c0"
+
 [[package]]
 name = "ecdsa"
 version = "0.12.4"
@@ -851,7 +880,9 @@ dependencies = [
  "Inflector",
  "anyhow",
  "cargo_metadata",
+ "cfg-if 1.0.0",
  "ethers-core",
+ "getrandom 0.2.3",
  "hex",
  "once_cell",
  "proc-macro2",
@@ -916,6 +947,7 @@ dependencies = [
  "ethers-signers",
  "futures-util",
  "hex",
+ "instant",
  "rand 0.8.4",
  "reqwest",
  "serde",
@@ -942,6 +974,7 @@ dependencies = [
  "futures-timer",
  "futures-util",
  "hex",
+ "parking_lot",
  "pin-project",
  "reqwest",
  "serde",
@@ -954,6 +987,11 @@ dependencies = [
  "tracing",
  "tracing-futures",
  "url",
+ "wasm-bindgen",
+ "wasm-bindgen-futures",
+ "wasm-timer",
+ "web-sys",
+ "ws_stream_wasm",
 ]
 
 [[package]]
@@ -1434,6 +1472,19 @@ dependencies = [
  "hashbrown",
 ]
 
+[[package]]
+name = "instant"
+version = "0.1.10"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "bee0328b1209d157ef001c94dd85b4f8f64139adb0eac2659f4b08382b2f474d"
+dependencies = [
+ "cfg-if 1.0.0",
+ "js-sys",
+ "time 0.2.27",
+ "wasm-bindgen",
+ "web-sys",
+]
+
 [[package]]
 name = "ipnet"
 version = "2.3.1"
@@ -1498,6 +1549,15 @@ dependencies = [
  "vcpkg",
 ]
 
+[[package]]
+name = "lock_api"
+version = "0.4.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "0382880606dff6d15c9476c416d18690b72742aa7b605bb6dd6ec9030fbf07eb"
+dependencies = [
+ "scopeguard",
+]
+
 [[package]]
 name = "log"
 version = "0.4.14"
@@ -1753,6 +1813,31 @@ dependencies = [
  "syn",
 ]
 
+[[package]]
+name = "parking_lot"
+version = "0.11.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "6d7744ac029df22dca6284efe4e898991d28e3085c706c972bcd7da4a27a15eb"
+dependencies = [
+ "instant",
+ "lock_api",
+ "parking_lot_core",
+]
+
+[[package]]
+name = "parking_lot_core"
+version = "0.8.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "fa7a782938e745763fe6907fc6ba86946d72f49fe7e21de074e08128a99fb018"
+dependencies = [
+ "cfg-if 1.0.0",
+ "instant",
+ "libc",
+ "redox_syscall",
+ "smallvec",
+ "winapi",
+]
+
 [[package]]
 name = "password-hash"
 version = "0.2.2"
@@ -1783,6 +1868,25 @@ version = "2.1.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "d4fd5641d01c8f18a23da7b6fe29298ff4b55afcccdf78973b24cf3175fee32e"
 
+[[package]]
+name = "pest"
+version = "2.1.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "10f4872ae94d7b90ae48754df22fd42ad52ce740b8f370b03da4835417403e53"
+dependencies = [
+ "ucd-trie",
+]
+
+[[package]]
+name = "pharos"
+version = "0.5.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "235c4b2ebc9552f5eba94ec982acb6c12f224980878e5b74a7d61806bb9c3591"
+dependencies = [
+ "futures",
+ "rustc_version 0.4.0",
+]
+
 [[package]]
 name = "pin-project"
 version = "1.0.8"
@@ -2175,7 +2279,7 @@ dependencies = [
  "log",
  "rusoto_credential",
  "rusoto_signature",
- "rustc_version",
+ "rustc_version 0.4.0",
  "serde",
  "serde_json",
  "tokio",
@@ -2234,7 +2338,7 @@ dependencies = [
  "percent-encoding",
  "pin-project-lite",
  "rusoto_credential",
- "rustc_version",
+ "rustc_version 0.4.0",
  "serde",
  "sha2 0.9.5",
  "tokio",
@@ -2252,13 +2356,31 @@ version = "2.1.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "3e75f6a532d0fd9f7f13144f392b6ad56a32696bfcd9c78f797f16bbb6f072d6"
 
+[[package]]
+name = "rustc_version"
+version = "0.2.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "138e3e0acb6c9fb258b19b67cb8abd63c00679d2851805ea151465464fe9030a"
+dependencies = [
+ "semver 0.9.0",
+]
+
+[[package]]
+name = "rustc_version"
+version = "0.3.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "f0dfe2087c51c460008730de8b57e6a320782fbfb312e1f4d520e6c6fae155ee"
+dependencies = [
+ "semver 0.11.0",
+]
+
 [[package]]
 name = "rustc_version"
 version = "0.4.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "bfa0f585226d2e68097d4f95d113b15b83a82e819ab25717ec0590d9584ef366"
 dependencies = [
- "semver",
+ "semver 1.0.4",
 ]
 
 [[package]]
@@ -2311,6 +2433,12 @@ dependencies = [
  "winapi",
 ]
 
+[[package]]
+name = "scopeguard"
+version = "1.1.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "d29ab0c6d3fc0ee92fe66e2d99f700eab17a8d57d1c1d3b748380fb20baa78cd"
+
 [[package]]
 name = "scrypt"
 version = "0.7.0"
@@ -2358,6 +2486,24 @@ dependencies = [
  "libc",
 ]
 
+[[package]]
+name = "semver"
+version = "0.9.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "1d7eb9ef2c18661902cc47e535f9bc51b78acd254da71d375c2f6720d9a40403"
+dependencies = [
+ "semver-parser 0.7.0",
+]
+
+[[package]]
+name = "semver"
+version = "0.11.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "f301af10236f6df4160f7c3f04eec6dbc70ace82d23326abad5edee88801c6b6"
+dependencies = [
+ "semver-parser 0.10.2",
+]
+
 [[package]]
 name = "semver"
 version = "1.0.4"
@@ -2367,6 +2513,27 @@ dependencies = [
  "serde",
 ]
 
+[[package]]
+name = "semver-parser"
+version = "0.7.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "388a1df253eca08550bef6c72392cfe7c30914bf41df5269b68cbd6ff8f570a3"
+
+[[package]]
+name = "semver-parser"
+version = "0.10.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "00b0bef5b7f9e0df16536d3961cfb6e84331c065b4066afb39768d0e319411f7"
+dependencies = [
+ "pest",
+]
+
+[[package]]
+name = "send_wrapper"
+version = "0.5.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "930c0acf610d3fdb5e2ab6213019aaa04e227ebe9547b0649ba599b16d788bd7"
+
 [[package]]
 name = "serde"
 version = "1.0.127"
@@ -2433,6 +2600,12 @@ dependencies = [
  "opaque-debug 0.3.0",
 ]
 
+[[package]]
+name = "sha1"
+version = "0.6.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "2579985fda508104f7587689507983eadd6a6e84dd35d6d115361f530916fa0d"
+
 [[package]]
 name = "sha2"
 version = "0.8.2"
@@ -2554,12 +2727,70 @@ dependencies = [
  "der",
 ]
 
+[[package]]
+name = "standback"
+version = "0.2.17"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "e113fb6f3de07a243d434a56ec6f186dfd51cb08448239fe7bcae73f87ff28ff"
+dependencies = [
+ "version_check",
+]
+
 [[package]]
 name = "static_assertions"
 version = "1.1.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "a2eb9349b6444b326872e140eb1cf5e7c522154d69e7a0ffb0fb81c06b37543f"
 
+[[package]]
+name = "stdweb"
+version = "0.4.20"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "d022496b16281348b52d0e30ae99e01a73d737b2f45d38fed4edf79f9325a1d5"
+dependencies = [
+ "discard",
+ "rustc_version 0.2.3",
+ "stdweb-derive",
+ "stdweb-internal-macros",
+ "stdweb-internal-runtime",
+ "wasm-bindgen",
+]
+
+[[package]]
+name = "stdweb-derive"
+version = "0.5.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "c87a60a40fccc84bef0652345bbbbbe20a605bf5d0ce81719fc476f5c03b50ef"
+dependencies = [
+ "proc-macro2",
+ "quote",
+ "serde",
+ "serde_derive",
+ "syn",
+]
+
+[[package]]
+name = "stdweb-internal-macros"
+version = "0.2.9"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "58fa5ff6ad0d98d1ffa8cb115892b6e69d67799f6763e162a1c9db421dc22e11"
+dependencies = [
+ "base-x",
+ "proc-macro2",
+ "quote",
+ "serde",
+ "serde_derive",
+ "serde_json",
+ "sha1",
+ "syn",
+]
+
+[[package]]
+name = "stdweb-internal-runtime"
+version = "0.1.5"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "213701ba3370744dcd1a12960caa4843b3d68b4d1c0a5d575e0d65b2ee9d16c0"
+
 [[package]]
 name = "subtle"
 version = "2.4.1"
@@ -2648,6 +2879,44 @@ dependencies = [
  "winapi",
 ]
 
+[[package]]
+name = "time"
+version = "0.2.27"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "4752a97f8eebd6854ff91f1c1824cd6160626ac4bd44287f7f4ea2035a02a242"
+dependencies = [
+ "const_fn",
+ "libc",
+ "standback",
+ "stdweb",
+ "time-macros",
+ "version_check",
+ "winapi",
+]
+
+[[package]]
+name = "time-macros"
+version = "0.1.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "957e9c6e26f12cb6d0dd7fc776bb67a706312e7299aed74c8dd5b17ebb27e2f1"
+dependencies = [
+ "proc-macro-hack",
+ "time-macros-impl",
+]
+
+[[package]]
+name = "time-macros-impl"
+version = "0.1.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "fd3c141a1b43194f3f56a1411225df8646c55781d5f26db825b3d98507eb482f"
+dependencies = [
+ "proc-macro-hack",
+ "proc-macro2",
+ "quote",
+ "standback",
+ "syn",
+]
+
 [[package]]
 name = "tiny-keccak"
 version = "2.0.2"
@@ -2891,6 +3160,12 @@ version = "1.13.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "879f6906492a7cd215bfa4cf595b600146ccfac0c79bcbd1f3000162af5e8b06"
 
+[[package]]
+name = "ucd-trie"
+version = "0.1.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "56dee185309b50d1f11bfedef0fe6d036842e3fb77413abef29f8f8d1c5d4c1c"
+
 [[package]]
 name = "uint"
 version = "0.9.1"
@@ -3066,6 +3341,21 @@ version = "0.2.76"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "acdb075a845574a1fa5f09fd77e43f7747599301ea3417a9fbffdeedfc1f4a29"
 
+[[package]]
+name = "wasm-timer"
+version = "0.2.5"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "be0ecb0db480561e9a7642b5d3e4187c128914e58aa84330b9493e3eb68c5e7f"
+dependencies = [
+ "futures",
+ "js-sys",
+ "parking_lot",
+ "pin-utils",
+ "wasm-bindgen",
+ "wasm-bindgen-futures",
+ "web-sys",
+]
+
 [[package]]
 name = "web-sys"
 version = "0.3.53"
@@ -3126,6 +3416,24 @@ dependencies = [
  "winapi",
 ]
 
+[[package]]
+name = "ws_stream_wasm"
+version = "0.7.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "47ca1ab42f5afed7fc332b22b6e932ca5414b209465412c8cdf0ad23bc0de645"
+dependencies = [
+ "async_io_stream",
+ "futures",
+ "js-sys",
+ "pharos",
+ "rustc_version 0.4.0",
+ "send_wrapper",
+ "thiserror",
+ "wasm-bindgen",
+ "wasm-bindgen-futures",
+ "web-sys",
+]
+
 [[package]]
 name = "wyz"
 version = "0.2.0"

Cargo.toml

@@ -21,6 +21,9 @@ members = [
     "ethers-middleware",
 ]
 
+exclude = [
+    "examples/ethers-wasm",
+]
 
 [package.metadata.docs.rs]
 all-features = true

ethers-contract/Cargo.toml

@@ -28,8 +28,9 @@ ethers = { version = "0.4.0", path = ".." }
 ethers-providers = { version = "0.4.6", path = "../ethers-providers", default-features = false, features = ["ws"] }
 ethers-signers = { version = "0.4.6", path = "../ethers-signers" }
 ethers-middleware = { version = "0.4.8", path = "../ethers-middleware" }
-tokio = { version = "1.5", default-features = false, features = ["macros"] }
 
+[target.'cfg(not(target_arch = "wasm32"))'.dev-dependencies]
+tokio = { version = "1.5", default-features = false, features = ["macros"] }
 
 [features]
 abigen = ["ethers-contract-abigen", "ethers-contract-derive"]

ethers-contract/ethers-contract-abigen/Cargo.toml

@@ -24,6 +24,11 @@ hex = { version = "0.4.2", default-features = false, features = ["std"] }
 reqwest = { version = "0.11.3", features = ["blocking"] }
 once_cell = { version = "1.8.0", default-features = false }
 cargo_metadata = "0.14.0"
+cfg-if = "1.0.0"
+
+[target.'cfg(not(target_arch = "wasm32"))'.dependencies]
+# NOTE: this enables wasm compatibility for getrandom indirectly
+getrandom = { version = "0.2", features = ["js"] }
 
 [package.metadata.docs.rs]
 all-features = true

ethers-contract/ethers-contract-abigen/src/source.rs

@@ -3,6 +3,7 @@ use super::util;
 use ethers_core::types::Address;
 
 use anyhow::{anyhow, Context, Error, Result};
+use cfg_if::cfg_if;
 use std::{
     borrow::Cow,
     env, fs,
@@ -77,8 +78,21 @@ impl Source {
         P: AsRef<Path>,
         S: AsRef<str>,
     {
+        cfg_if! {
+             if #[cfg(target_arch = "wasm32")] {
+               let root = root.as_ref();
+                let root = if root.starts_with("/") {
+                   format!("file:://{}", root.display())
+                } else {
+                    format!("{}", root.display())
+                };
+                let base = Url::parse(&root)
+                    .map_err(|_| anyhow!("root path '{}' is not absolute"))?;
+             } else {
                    let base = Url::from_directory_path(root)
             .map_err(|_| anyhow!("root path '{}' is not absolute"))?;
+            }
+        }
         let url = base.join(source.as_ref())?;
 
         match url.scheme() {
@@ -134,8 +148,18 @@ impl Source {
 
     /// Retrieves the source JSON of the artifact this will either read the JSON
     /// from the file system or retrieve a contract ABI from the network
-    /// dependending on the source type.
+    /// depending on the source type.
     pub fn get(&self) -> Result<String> {
+        cfg_if! {
+             if #[cfg(target_arch = "wasm32")] {
+                 match self {
+                    Source::Local(path) => get_local_contract(path),
+                    Source::Http(_) =>   panic!("Http abi location are not supported for wasm"),
+                    Source::Etherscan(_) => panic!("Etherscan abi location are not supported for wasm"),
+                    Source::Npm(_) => panic!("npm abi location are not supported for wasm"),
+                    Source::String(abi) => Ok(abi.clone()),
+                }
+             } else {
                 match self {
                     Source::Local(path) => get_local_contract(path),
                     Source::Http(url) => get_http_contract(url),
@@ -145,6 +169,8 @@ impl Source {
                 }
             }
         }
+    }
+}
 
 impl FromStr for Source {
     type Err = Error;
@@ -179,6 +205,7 @@ fn get_local_contract(path: &Path) -> Result<String> {
 }
 
 /// Retrieves a Truffle artifact or ABI from an HTTP URL.
+#[cfg(not(target_arch = "wasm32"))]
 fn get_http_contract(url: &Url) -> Result<String> {
     let json = util::http_get(url.as_str())
         .with_context(|| format!("failed to retrieve JSON from {}", url))?;
@@ -187,6 +214,7 @@ fn get_http_contract(url: &Url) -> Result<String> {
 
 /// Retrieves a contract ABI from the Etherscan HTTP API and wraps it in an
 /// artifact JSON for compatibility with the code generation facilities.
+#[cfg(not(target_arch = "wasm32"))]
 fn get_etherscan_contract(address: Address) -> Result<String> {
     // NOTE: We do not retrieve the bytecode since deploying contracts with the
     //   same bytecode is unreliable as the libraries have already linked and
@@ -206,6 +234,7 @@ fn get_etherscan_contract(address: Address) -> Result<String> {
 }
 
 /// Retrieves a Truffle artifact or ABI from an npm package through `unpkg.io`.
+#[cfg(not(target_arch = "wasm32"))]
 fn get_npm_contract(package: &str) -> Result<String> {
     let unpkg_url = format!("https://unpkg.io/{}", package);
     let json = util::http_get(&unpkg_url)

ethers-contract/ethers-contract-abigen/src/util.rs

@@ -103,6 +103,7 @@ where
     Ok(address_str[2..].parse()?)
 }
 
+#[cfg(not(target_arch = "wasm32"))]
 /// Perform an HTTP GET request and return the contents of the response.
 pub fn http_get(url: &str) -> Result<String> {
     Ok(reqwest::blocking::get(url)?.text()?)

ethers-contract/tests/common/mod.rs

@@ -1,3 +1,4 @@
+#![cfg(not(target_arch = "wasm32"))]
 mod derive;
 use ethers_core::{
     abi::Abi,

ethers-contract/tests/contract.rs

@@ -1,3 +1,4 @@
+#![cfg(not(target_arch = "wasm32"))]
 use ethers::{
     contract::ContractFactory,
     types::{Filter, ValueOrArray, H256},

ethers-core/Cargo.toml

@@ -31,6 +31,7 @@ glob = { version = "0.3.0", default-features = false }
 bytes = { version = "1.0.1", features = ["serde"] }
 hex = { version = "0.4.3", default-features = false, features = ["std"] }
 
+[target.'cfg(not(target_arch = "wasm32"))'.dependencies]
 # async
 tokio = { version = "1.5", default-features = false, optional = true}
 futures-util = { version = "0.3.16", optional = true }

ethers-core/src/utils/mod.rs

@@ -291,6 +291,7 @@ fn base_fee_surged(base_fee_per_gas: U256) -> U256 {
 ///
 /// Does not guarantee that the given port is unused after the function exists, just that it was
 /// unused before the function started (i.e., it does not reserve a port).
+#[cfg(not(target_arch = "wasm32"))]
 pub(crate) fn unused_port() -> u16 {
     let listener = std::net::TcpListener::bind("127.0.0.1:0")
         .expect("Failed to create TCP listener to find unused port");

ethers-middleware/Cargo.toml

@@ -32,12 +32,17 @@ reqwest = { version = "0.11.4", default-features = false, features = ["json", "r
 url = { version = "2.2.2", default-features = false }
 
 serde_json = { version = "1.0.64", default-features = false }
+instant = {version = "0.1.10", features = ["now"] }
+
+[target.'cfg(not(target_arch = "wasm32"))'.dependencies]
 tokio = { version = "1.5" }
 
 [dev-dependencies]
 ethers = { version = "0.4.0", path = ".." }
 hex = { version = "0.4.3", default-features = false, features = ["std"] }
 rand = { version = "0.8.4", default-features = false }
+
+[target.'cfg(not(target_arch = "wasm32"))'.dev-dependencies]
 tokio = { version = "1.5", default-features = false, features = ["rt", "macros", "time"] }
 
 [features]

ethers-middleware/src/gas_escalator/mod.rs

@@ -9,12 +9,18 @@ use async_trait::async_trait;
 use ethers_core::types::{BlockId, TransactionRequest, TxHash, U256};
 use ethers_providers::{interval, FromErr, Middleware, PendingTransaction, StreamExt};
 use futures_util::lock::Mutex;
+use instant::Instant;
+use std::pin::Pin;
 use std::sync::Arc;
-use std::{pin::Pin, time::Instant};
 use thiserror::Error;
 
+#[cfg(not(target_arch = "wasm32"))]
 use tokio::spawn;
-use tracing_futures::Instrument;
+
+#[cfg(target_arch = "wasm32")]
+type WatcherFuture<'a> = Pin<Box<dyn futures_util::stream::Stream<Item = ()> + 'a>>;
+#[cfg(not(target_arch = "wasm32"))]
+type WatcherFuture<'a> = Pin<Box<dyn futures_util::stream::Stream<Item = ()> + Send + 'a>>;
 
 /// Trait for fetching updated gas prices after a transaction has been first
 /// broadcast
@@ -69,7 +75,8 @@ pub struct GasEscalatorMiddleware<M, E> {
     frequency: Frequency,
 }
 
-#[async_trait]
+#[cfg_attr(target_arch = "wasm32", async_trait(?Send))]
+#[cfg_attr(not(target_arch = "wasm32"), async_trait)]
 impl<M, E> Middleware for GasEscalatorMiddleware<M, E>
 where
     M: Middleware,
@@ -118,11 +125,14 @@ where
     /// Initializes the middleware with the provided gas escalator and the chosen
     /// escalation frequency (per block or per second)
     #[allow(clippy::let_and_return)]
+    #[cfg(not(target_arch = "wasm32"))]
     pub fn new(inner: M, escalator: E, frequency: Frequency) -> Self
     where
         E: Clone + 'static,
         M: Clone + 'static,
     {
+        use tracing_futures::Instrument;
+
         let this = Self {
             inner: Arc::new(inner),
             escalator,
@@ -146,9 +156,8 @@ where
 
     /// Re-broadcasts pending transactions with a gas price escalator
     pub async fn escalate(&self) -> Result<(), GasEscalatorError<M>> {
-        // the escalation frequency is either on a per-block basis, or on a duratoin basis
+        // the escalation frequency is either on a per-block basis, or on a duration basis
-        let mut watcher: Pin<Box<dyn futures_util::stream::Stream<Item = ()> + Send>> =
+        let mut watcher: WatcherFuture = match self.frequency {
-            match self.frequency {
             Frequency::PerBlock => Box::pin(
                 self.inner
                     .watch_blocks()

ethers-middleware/src/gas_oracle/eth_gas_station.rs

@@ -93,7 +93,8 @@ impl EthGasStation {
     }
 }
 
-#[async_trait]
+#[cfg_attr(target_arch = "wasm32", async_trait(?Send))]
+#[cfg_attr(not(target_arch = "wasm32"), async_trait)]
 impl GasOracle for EthGasStation {
     async fn fetch(&self) -> Result<U256, GasOracleError> {
         let res = self.query().await?;

ethers-middleware/src/gas_oracle/etherchain.rs

@@ -64,7 +64,8 @@ impl Etherchain {
     }
 }
 
-#[async_trait]
+#[cfg_attr(target_arch = "wasm32", async_trait(?Send))]
+#[cfg_attr(not(target_arch = "wasm32"), async_trait)]
 impl GasOracle for Etherchain {
     async fn fetch(&self) -> Result<U256, GasOracleError> {
         let res = self.query().await?;

ethers-middleware/src/gas_oracle/etherscan.rs

@@ -92,7 +92,8 @@ impl Etherscan {
     }
 }
 
-#[async_trait]
+#[cfg_attr(target_arch = "wasm32", async_trait(?Send))]
+#[cfg_attr(not(target_arch = "wasm32"), async_trait)]
 impl GasOracle for Etherscan {
     async fn fetch(&self) -> Result<U256, GasOracleError> {
         if matches!(self.gas_category, GasCategory::Fastest) {

ethers-middleware/src/gas_oracle/gas_now.rs

@@ -67,7 +67,8 @@ impl GasNow {
     }
 }
 
-#[async_trait]
+#[cfg_attr(target_arch = "wasm32", async_trait(?Send))]
+#[cfg_attr(not(target_arch = "wasm32"), async_trait)]
 impl GasOracle for GasNow {
     async fn fetch(&self) -> Result<U256, GasOracleError> {
         let res = self.query().await?;

ethers-middleware/src/gas_oracle/middleware.rs

@@ -39,7 +39,8 @@ impl<M: Middleware> FromErr<M::Error> for MiddlewareError<M> {
     }
 }
 
-#[async_trait]
+#[cfg_attr(target_arch = "wasm32", async_trait(?Send))]
+#[cfg_attr(not(target_arch = "wasm32"), async_trait)]
 impl<M, G> Middleware for GasOracleMiddleware<M, G>
 where
     M: Middleware,

ethers-middleware/src/gas_oracle/mod.rs

@@ -65,7 +65,8 @@ pub enum GasOracleError {
 /// # Ok(())
 /// # }
 /// ```
-#[async_trait]
+#[cfg_attr(target_arch = "wasm32", async_trait(?Send))]
+#[cfg_attr(not(target_arch = "wasm32"), async_trait)]
 pub trait GasOracle: Send + Sync + std::fmt::Debug {
     /// Makes an asynchronous HTTP query to the underlying `GasOracle`
     ///

ethers-middleware/src/nonce_manager.rs

@@ -69,7 +69,8 @@ impl<M: Middleware> FromErr<M::Error> for NonceManagerError<M> {
     }
 }
 
-#[async_trait]
+#[cfg_attr(target_arch = "wasm32", async_trait(?Send))]
+#[cfg_attr(not(target_arch = "wasm32"), async_trait)]
 impl<M> Middleware for NonceManagerMiddleware<M>
 where
     M: Middleware,

ethers-middleware/src/policy.rs

@@ -6,7 +6,8 @@ use std::fmt::Debug;
 use thiserror::Error;
 
 /// Basic trait to ensure that transactions about to be sent follow certain rules.
-#[async_trait]
+#[cfg_attr(target_arch = "wasm32", async_trait(?Send))]
+#[cfg_attr(not(target_arch = "wasm32"), async_trait)]
 pub trait Policy: Sync + Send + Debug {
     type Error: Sync + Send + Debug;
 
@@ -20,7 +21,8 @@ pub trait Policy: Sync + Send + Debug {
 #[derive(Debug, Clone, Copy)]
 pub struct AllowEverything;
 
-#[async_trait]
+#[cfg_attr(target_arch = "wasm32", async_trait(?Send))]
+#[cfg_attr(not(target_arch = "wasm32"), async_trait)]
 impl Policy for AllowEverything {
     type Error = ();
 
@@ -33,7 +35,8 @@ impl Policy for AllowEverything {
 #[derive(Debug, Clone, Copy)]
 pub struct RejectEverything;
 
-#[async_trait]
+#[cfg_attr(target_arch = "wasm32", async_trait(?Send))]
+#[cfg_attr(not(target_arch = "wasm32"), async_trait)]
 impl Policy for RejectEverything {
     type Error = ();
 
@@ -77,7 +80,8 @@ pub enum PolicyMiddlewareError<M: Middleware, P: Policy> {
     MiddlewareError(M::Error),
 }
 
-#[async_trait]
+#[cfg_attr(target_arch = "wasm32", async_trait(?Send))]
+#[cfg_attr(not(target_arch = "wasm32"), async_trait)]
 impl<M, P> Middleware for PolicyMiddleware<M, P>
 where
     M: Middleware,

ethers-middleware/src/signer.rs

@@ -152,7 +152,8 @@ where
     }
 }
 
-#[async_trait]
+#[cfg_attr(target_arch = "wasm32", async_trait(?Send))]
+#[cfg_attr(not(target_arch = "wasm32"), async_trait)]
 impl<M, S> Middleware for SignerMiddleware<M, S>
 where
     M: Middleware,
@@ -246,7 +247,7 @@ where
     }
 }
 
-#[cfg(all(test, not(feature = "celo")))]
+#[cfg(all(test, not(feature = "celo"), not(target_arch = "wasm32")))]
 mod tests {
     use super::*;
     use ethers::{providers::Provider, signers::LocalWallet};

ethers-middleware/src/transformer/middleware.rs

@@ -39,7 +39,8 @@ impl<M: Middleware> FromErr<M::Error> for TransformerMiddlewareError<M> {
     }
 }
 
-#[async_trait]
+#[cfg_attr(target_arch = "wasm32", async_trait(?Send))]
+#[cfg_attr(not(target_arch = "wasm32"), async_trait)]
 impl<M, T> Middleware for TransformerMiddleware<M, T>
 where
     M: Middleware,

ethers-middleware/tests/gas_escalator.rs

@@ -1,3 +1,4 @@
+#![cfg(not(target_arch = "wasm32"))]
 use ethers_core::types::*;
 use ethers_middleware::{
     gas_escalator::{Frequency, GasEscalatorMiddleware, GeometricGasPrice},

ethers-middleware/tests/gas_oracle.rs

@@ -1,3 +1,4 @@
+#![cfg(not(target_arch = "wasm32"))]
 use ethers_core::{types::*, utils::Ganache};
 use ethers_middleware::gas_oracle::{
     EthGasStation, Etherchain, Etherscan, GasCategory, GasNow, GasOracle, GasOracleMiddleware,

ethers-middleware/tests/nonce_manager.rs

@@ -1,3 +1,4 @@
+#![cfg(not(target_arch = "wasm32"))]
 #[tokio::test]
 #[cfg(not(feature = "celo"))]
 async fn nonce_manager() {

ethers-middleware/tests/signer.rs

@@ -1,3 +1,4 @@
+#![cfg(not(target_arch = "wasm32"))]
 use ethers_providers::{Http, Middleware, Provider};
 
 use ethers_core::types::TransactionRequest;

ethers-middleware/tests/stack.rs

@@ -1,3 +1,4 @@
+#![cfg(not(target_arch = "wasm32"))]
 #[cfg(not(feature = "celo"))]
 mod tests {
     use ethers_core::{rand::thread_rng, types::TransactionRequest, utils::Ganache};

ethers-middleware/tests/transformer.rs

@@ -1,3 +1,4 @@
+#![cfg(not(target_arch = "wasm32"))]
 use ethers_contract::{BaseContract, ContractFactory};
 use ethers_core::{
     types::*,

ethers-providers/Cargo.toml

@@ -36,14 +36,27 @@ pin-project = { version = "1.0.7", default-features = false }
 tracing = { version = "0.1.26", default-features = false }
 tracing-futures = { version = "0.2.5", default-features = false, features = ["std-future"] }
 
+bytes = { version  = "1.0.1", default-features = false, optional = true }
+
+[target.'cfg(not(target_arch = "wasm32"))'.dependencies]
 # tokio
+tokio-util = { version = "0.6.7", default-features = false, features = ["io"], optional = true }
 tokio = { version = "1.5", default-features = false, optional = true }
 tokio-tungstenite = { version = "0.15.0", default-features = false, features = ["connect"], optional = true }
-tokio-util = { version = "0.6.7", default-features = false, features = ["io"], optional = true }
+
-bytes = { version  = "1.0.1", default-features = false, optional = true }
+[target.'cfg(target_arch = "wasm32")'.dependencies]
+ws_stream_wasm = "0.7"
+wasm-bindgen = "0.2"
+wasm-bindgen-futures = "0.4"
+web-sys = { version  = "0.3", features = ["console"] }
+wasm-timer = "0.2"
+# this is currently necessary for `wasm-timer::Delay` to work
+parking_lot = { version = "0.11", features = ["wasm-bindgen"] }
 
 [dev-dependencies]
 ethers = { version = "0.4.0", path = ".." }
+
+[target.'cfg(not(target_arch = "wasm32"))'.dev-dependencies]
 tokio = { version = "1.5", default-features = false, features = ["rt", "macros"] }
 tempfile = "3.2.0"
 

ethers-providers/src/lib.rs

@@ -90,10 +90,14 @@ use std::{error::Error, fmt::Debug, future::Future, pin::Pin, str::FromStr};
 pub use provider::{FilterKind, Provider, ProviderError};
 
 // Helper type alias
+#[cfg(target_arch = "wasm32")]
+pub(crate) type PinBoxFut<'a, T> = Pin<Box<dyn Future<Output = Result<T, ProviderError>> + 'a>>;
+#[cfg(not(target_arch = "wasm32"))]
 pub(crate) type PinBoxFut<'a, T> =
     Pin<Box<dyn Future<Output = Result<T, ProviderError>> + Send + 'a>>;
 
-#[async_trait]
+#[cfg_attr(target_arch = "wasm32", async_trait(?Send))]
+#[cfg_attr(not(target_arch = "wasm32"), async_trait)]
 #[auto_impl(&, Box, Arc)]
 /// Trait which must be implemented by data transports to be used with the Ethereum
 /// JSON-RPC provider.
@@ -125,8 +129,6 @@ where
     }
 }
 
-#[async_trait]
-#[auto_impl(&, Box, Arc)]
 /// A middleware allows customizing requests send and received from an ethereum node.
 ///
 /// Writing a middleware is as simple as:
@@ -182,6 +184,9 @@ where
 ///     }
 /// }
 /// ```
+#[cfg_attr(target_arch = "wasm32", async_trait(?Send))]
+#[cfg_attr(not(target_arch = "wasm32"), async_trait)]
+#[auto_impl(&, Box, Arc)]
 pub trait Middleware: Sync + Send + Debug {
     type Error: Sync + Send + Error + FromErr<<Self::Inner as Middleware>::Error>;
     type Provider: JsonRpcClient;
@@ -759,7 +764,8 @@ where
 }
 
 #[cfg(feature = "celo")]
-#[async_trait]
+#[cfg_attr(target_arch = "wasm32", async_trait(?Send))]
+#[cfg_attr(not(target_arch = "wasm32"), async_trait)]
 pub trait CeloMiddleware: Middleware {
     async fn get_validators_bls_public_keys<T: Into<BlockId> + Send + Sync>(
         &self,

ethers-providers/src/pending_transaction.rs

@@ -5,7 +5,6 @@ use crate::{
 };
 use ethers_core::types::{Transaction, TransactionReceipt, TxHash, U64};
 use futures_core::stream::Stream;
-use futures_timer::Delay;
 use futures_util::stream::StreamExt;
 use pin_project::pin_project;
 use std::{
@@ -17,6 +16,11 @@ use std::{
     time::Duration,
 };
 
+#[cfg(not(target_arch = "wasm32"))]
+use futures_timer::Delay;
+#[cfg(target_arch = "wasm32")]
+use wasm_timer::Delay;
+
 /// A pending transaction is a transaction which has been submitted but is not yet mined.
 /// `await`'ing on a pending transaction will resolve to a transaction receipt
 /// once the transaction has enough `confirmations`. The default number of confirmations
@@ -258,7 +262,7 @@ impl<'a, P> Deref for PendingTransaction<'a, P> {
 // We box the TransactionReceipts to keep the enum small.
 enum PendingTxState<'a> {
     /// Initial delay to ensure the GettingTx loop doesn't immediately fail
-    InitialDelay(Pin<Box<futures_timer::Delay>>),
+    InitialDelay(Pin<Box<Delay>>),
 
     /// Waiting for interval to elapse before calling API again
     PausedGettingTx,

ethers-providers/src/provider.rs

@@ -2,9 +2,12 @@ use crate::{
     ens,
     pubsub::{PubsubClient, SubscriptionStream},
     stream::{FilterWatcher, DEFAULT_POLL_INTERVAL},
-    FeeHistory, FromErr, Http as HttpProvider, JsonRpcClient, MockProvider, PendingTransaction,
+    FeeHistory, FromErr, JsonRpcClient, MockProvider, PendingTransaction,
 };
 
+#[cfg(not(target_arch = "wasm32"))]
+use crate::Http as HttpProvider;
+
 use ethers_core::{
     abi::{self, Detokenize, ParamType},
     types::{
@@ -23,6 +26,7 @@ use async_trait::async_trait;
 use hex::FromHex;
 use serde::{de::DeserializeOwned, Serialize};
 use thiserror::Error;
+#[cfg(not(target_arch = "wasm32"))]
 use url::{ParseError, Url};
 
 use std::{convert::TryFrom, fmt::Debug, time::Duration};
@@ -167,7 +171,8 @@ impl<P: JsonRpcClient> Provider<P> {
 }
 
 #[cfg(feature = "celo")]
-#[async_trait]
+#[cfg_attr(target_arch = "wasm32", async_trait(?Send))]
+#[cfg_attr(not(target_arch = "wasm32"), async_trait)]
 impl<P: JsonRpcClient> CeloMiddleware for Provider<P> {
     async fn get_validators_bls_public_keys<T: Into<BlockId> + Send + Sync>(
         &self,
@@ -179,7 +184,8 @@ impl<P: JsonRpcClient> CeloMiddleware for Provider<P> {
     }
 }
 
-#[async_trait]
+#[cfg_attr(target_arch = "wasm32", async_trait(?Send))]
+#[cfg_attr(not(target_arch = "wasm32"), async_trait)]
 impl<P: JsonRpcClient> Middleware for Provider<P> {
     type Error = ProviderError;
     type Provider = P;
@@ -870,14 +876,23 @@ impl<P: JsonRpcClient> Provider<P> {
 #[cfg(feature = "ws")]
 impl Provider<crate::Ws> {
     /// Direct connection to a websocket endpoint
+    #[cfg(not(target_arch = "wasm32"))]
     pub async fn connect(
         url: impl tokio_tungstenite::tungstenite::client::IntoClientRequest + Unpin,
     ) -> Result<Self, ProviderError> {
         let ws = crate::Ws::connect(url).await?;
         Ok(Self::new(ws))
     }
+
+    /// Direct connection to a websocket endpoint
+    #[cfg(target_arch = "wasm32")]
+    pub async fn connect(url: &str) -> Result<Self, ProviderError> {
+        let ws = crate::Ws::connect(url).await?;
+        Ok(Self::new(ws))
+    }
 }
 
+#[cfg(not(target_arch = "wasm32"))]
 #[cfg(feature = "ipc")]
 impl Provider<crate::Ipc> {
     /// Direct connection to an IPC socket.
@@ -926,6 +941,7 @@ fn decode_bytes<T: Detokenize>(param: ParamType, bytes: Bytes) -> T {
     T::from_tokens(tokens).expect("could not parse tokens as address")
 }
 
+#[cfg(not(target_arch = "wasm32"))]
 impl TryFrom<&str> for Provider<HttpProvider> {
     type Error = ParseError;
 
@@ -934,6 +950,7 @@ impl TryFrom<&str> for Provider<HttpProvider> {
     }
 }
 
+#[cfg(not(target_arch = "wasm32"))]
 impl TryFrom<String> for Provider<HttpProvider> {
     type Error = ParseError;
 
@@ -943,8 +960,13 @@ impl TryFrom<String> for Provider<HttpProvider> {
 }
 
 #[cfg(test)]
-mod ens_tests {
+#[cfg(not(target_arch = "wasm32"))]
+mod tests {
     use super::*;
+    use crate::Http;
+    use ethers_core::types::{TransactionRequest, H256};
+    use ethers_core::utils::Geth;
+    use futures_util::StreamExt;
 
     const INFURA: &str = "https://mainnet.infura.io/v3/c60b0bb42f8a4c6481ecd229eddaca27";
 
@@ -989,15 +1011,6 @@ mod ens_tests {
             .await
             .unwrap_err();
     }
-}
-
-#[cfg(test)]
-mod tests {
-    use super::*;
-    use crate::Http;
-    use ethers_core::types::{TransactionRequest, H256};
-    use ethers_core::utils::Geth;
-    use futures_util::StreamExt;
 
     #[tokio::test]
     #[cfg_attr(feature = "celo", ignore)]

ethers-providers/src/stream.rs

@@ -4,7 +4,6 @@ use ethers_core::types::{Transaction, TxHash, U256};
 
 use futures_core::stream::Stream;
 use futures_core::Future;
-use futures_timer::Delay;
 use futures_util::stream::FuturesUnordered;
 use futures_util::{stream, FutureExt, StreamExt};
 use pin_project::pin_project;
@@ -18,6 +17,11 @@ use std::{
     vec::IntoIter,
 };
 
+#[cfg(not(target_arch = "wasm32"))]
+use futures_timer::Delay;
+#[cfg(target_arch = "wasm32")]
+use wasm_timer::Delay;
+
 // https://github.com/tomusdrw/rust-web3/blob/befcb2fb8f3ca0a43e3081f68886fa327e64c8e6/src/api/eth_filter.rs#L20
 pub fn interval(duration: Duration) -> impl Stream<Item = ()> + Send + Unpin {
     stream::unfold((), move |_| Delay::new(duration).map(|_| Some(((), ())))).map(drop)
@@ -254,6 +258,7 @@ where
 }
 
 #[cfg(test)]
+#[cfg(not(target_arch = "wasm32"))]
 mod tests {
     use super::*;
     use crate::{Http, Ws};

ethers-providers/src/transports/http.rs

@@ -58,7 +58,8 @@ impl From<ClientError> for ProviderError {
     }
 }
 
-#[async_trait]
+#[cfg_attr(target_arch = "wasm32", async_trait(?Send))]
+#[cfg_attr(not(target_arch = "wasm32"), async_trait)]
 impl JsonRpcClient for Provider {
     type Error = ClientError;
 

ethers-providers/src/transports/mock.rs

@@ -23,7 +23,8 @@ impl Default for MockProvider {
     }
 }
 
-#[async_trait]
+#[cfg_attr(target_arch = "wasm32", async_trait(?Send))]
+#[cfg_attr(not(target_arch = "wasm32"), async_trait)]
 impl JsonRpcClient for MockProvider {
     type Error = MockError;
 
@@ -103,6 +104,7 @@ impl From<MockError> for ProviderError {
 }
 
 #[cfg(test)]
+#[cfg(not(target_arch = "wasm32"))]
 mod tests {
     use super::*;
     use crate::Middleware;

ethers-providers/src/transports/mod.rs

@@ -1,17 +1,34 @@
 mod common;
 
+macro_rules! if_wasm {
+    ($($item:item)*) => {$(
+        #[cfg(target_arch = "wasm32")]
+        $item
+    )*}
+}
+
+macro_rules! if_not_wasm {
+    ($($item:item)*) => {$(
+        #[cfg(not(target_arch = "wasm32"))]
+        $item
+    )*}
+}
+
+if_not_wasm! {
     mod http;
     pub use http::Provider as Http;
 
+
+    #[cfg(feature = "ipc")]
+    mod ipc;
+    #[cfg(feature = "ipc")]
+    pub use ipc::Ipc;
+}
+
 #[cfg(feature = "ws")]
 mod ws;
 #[cfg(feature = "ws")]
 pub use ws::Ws;
 
-#[cfg(feature = "ipc")]
-mod ipc;
-#[cfg(feature = "ipc")]
-pub use ipc::Ipc;
-
 mod mock;
 pub use mock::{MockError, MockProvider};

ethers-providers/src/transports/ws.rs

@@ -22,14 +22,46 @@ use std::{
     },
 };
 use thiserror::Error;
+
+if_wasm! {
+    use wasm_bindgen::prelude::*;
+    use wasm_bindgen_futures::spawn_local;
+    use ws_stream_wasm::*;
+
+    type Message = WsMessage;
+    type WsError = ws_stream_wasm::WsErr;
+    type WsStreamItem = Message;
+
+    macro_rules! error {
+        ( $( $t:tt )* ) => {
+            web_sys::console::error_1(&format!( $( $t )* ).into());
+        }
+    }
+    macro_rules! warn {
+        ( $( $t:tt )* ) => {
+            web_sys::console::warn_1(&format!( $( $t )* ).into());
+        }
+    }
+    macro_rules! debug {
+        ( $( $t:tt )* ) => {
+            web_sys::console::log_1(&format!( $( $t )* ).into());
+        }
+    }
+}
+
+if_not_wasm! {
     use tokio_tungstenite::{
         connect_async,
         tungstenite::{
             self,
-        protocol::{CloseFrame, Message},
+            protocol::CloseFrame,
         },
     };
-use tracing::{error, warn};
+    type Message = tungstenite::protocol::Message;
+    type WsError = tungstenite::Error;
+    type WsStreamItem = Result<Message, WsError>;
+    use tracing::{debug, error, warn};
+}
 
 type Pending = oneshot::Sender<Result<serde_json::Value, JsonRpcError>>;
 type Subscription = mpsc::UnboundedSender<serde_json::Value>;
@@ -84,11 +116,7 @@ impl Ws {
     /// The websocket connection must be initiated separately.
     pub fn new<S: 'static>(ws: S) -> Self
     where
-        S: Send
+        S: Send + Sync + Stream<Item = WsStreamItem> + Sink<Message, Error = WsError> + Unpin,
-            + Sync
-            + Stream<Item = Result<Message, tungstenite::Error>>
-            + Sink<Message, Error = tungstenite::Error>
-            + Unpin,
     {
         let (sink, stream) = mpsc::unbounded();
 
@@ -107,6 +135,17 @@ impl Ws {
     }
 
     /// Initializes a new WebSocket Client
+    #[cfg(target_arch = "wasm32")]
+    pub async fn connect(url: &str) -> Result<Self, ClientError> {
+        let (_, wsio) = WsMeta::connect(url, None)
+            .await
+            .expect_throw("Could not create websocket");
+
+        Ok(Self::new(wsio))
+    }
+
+    /// Initializes a new WebSocket Client
+    #[cfg(not(target_arch = "wasm32"))]
     pub async fn connect(
         url: impl tungstenite::client::IntoClientRequest + Unpin,
     ) -> Result<Self, ClientError> {
@@ -121,7 +160,8 @@ impl Ws {
     }
 }
 
-#[async_trait]
+#[cfg_attr(target_arch = "wasm32", async_trait(?Send))]
+#[cfg_attr(not(target_arch = "wasm32"), async_trait)]
 impl JsonRpcClient for Ws {
     type Error = ClientError;
 
@@ -181,11 +221,7 @@ struct WsServer<S> {
 
 impl<S> WsServer<S>
 where
-    S: Send
+    S: Send + Sync + Stream<Item = WsStreamItem> + Sink<Message, Error = WsError> + Unpin,
-        + Sync
-        + Stream<Item = Result<Message, tungstenite::Error>>
-        + Sink<Message, Error = tungstenite::Error>
-        + Unpin,
 {
     /// Instantiates the Websocket Server
     fn new(ws: S, requests: mpsc::UnboundedReceiver<Instruction>) -> Self {
@@ -215,12 +251,12 @@ where
         let f = async move {
             loop {
                 if self.is_done() {
-                    tracing::info!("work complete");
+                    debug!("work complete");
                     break;
                 }
                 match self.tick().await {
                     Err(ClientError::UnexpectedClose) => {
-                        tracing::error!("{}", ClientError::UnexpectedClose);
+                        error!("{}", ClientError::UnexpectedClose);
                         break;
                     }
                     Err(e) => {
@@ -231,6 +267,10 @@ where
             }
         };
 
+        #[cfg(target_arch = "wasm32")]
+        spawn_local(f);
+
+        #[cfg(not(target_arch = "wasm32"))]
         tokio::spawn(f);
     }
 
@@ -284,6 +324,7 @@ where
         }
     }
 
+    #[cfg(not(target_arch = "wasm32"))]
     async fn handle_ping(&mut self, inner: Vec<u8>) -> Result<(), ClientError> {
         self.ws.send(Message::Pong(inner)).await?;
         Ok(())
@@ -315,6 +356,15 @@ where
         Ok(())
     }
 
+    #[cfg(target_arch = "wasm32")]
+    async fn handle(&mut self, resp: Message) -> Result<(), ClientError> {
+        match resp {
+            Message::Text(inner) => self.handle_text(inner).await,
+            Message::Binary(buf) => Err(ClientError::UnexpectedBinary(buf)),
+        }
+    }
+
+    #[cfg(not(target_arch = "wasm32"))]
     async fn handle(&mut self, resp: Message) -> Result<(), ClientError> {
         match resp {
             Message::Text(inner) => self.handle_text(inner).await,
@@ -328,6 +378,28 @@ where
 
     /// Processes 1 instruction or 1 incoming websocket message
     #[allow(clippy::single_match)]
+    #[cfg(target_arch = "wasm32")]
+    async fn tick(&mut self) -> Result<(), ClientError> {
+        futures_util::select! {
+            // Handle requests
+            instruction = self.instructions.select_next_some() => {
+                self.service(instruction).await?;
+            },
+            // Handle ws messages
+            resp = self.ws.next() => match resp {
+                Some(resp) => self.handle(resp).await?,
+                None => {
+                    return Err(ClientError::UnexpectedClose);
+                },
+            }
+        };
+
+        Ok(())
+    }
+
+    /// Processes 1 instruction or 1 incoming websocket message
+    #[allow(clippy::single_match)]
+    #[cfg(not(target_arch = "wasm32"))]
     async fn tick(&mut self) -> Result<(), ClientError> {
         futures_util::select! {
             // Handle requests
@@ -371,7 +443,7 @@ pub enum ClientError {
 
     /// Thrown if there's an error over the WS connection
     #[error(transparent)]
-    TungsteniteError(#[from] tungstenite::Error),
+    TungsteniteError(#[from] WsError),
 
     #[error("{0}")]
     ChannelError(String),
@@ -381,8 +453,14 @@ pub enum ClientError {
 
     /// Remote server sent a Close message
     #[error("Websocket closed with info: {0:?}")]
+    #[cfg(not(target_arch = "wasm32"))]
     WsClosed(CloseFrame<'static>),
 
+    /// Remote server sent a Close message
+    #[error("Websocket closed with info")]
+    #[cfg(target_arch = "wasm32")]
+    WsClosed,
+
     /// Something caused the websocket to close
     #[error("WebSocket connection closed unexpectedly")]
     UnexpectedClose,
@@ -396,6 +474,7 @@ impl From<ClientError> for ProviderError {
 
 #[cfg(test)]
 #[cfg(not(feature = "celo"))]
+#[cfg(not(target_arch = "wasm32"))]
 mod tests {
     use super::*;
     use ethers_core::types::{Block, TxHash, U256};

ethers-providers/tests/provider.rs

@@ -1,3 +1,4 @@
+#![cfg(not(target_arch = "wasm32"))]
 use ethers::providers::{Http, Middleware, Provider};
 use std::{convert::TryFrom, time::Duration};
 

ethers-providers/tests/txpool.rs

@@ -1,3 +1,4 @@
+#![cfg(not(target_arch = "wasm32"))]
 use ethers::{
     providers::{Http, Middleware, Provider},
     types::TransactionRequest,

ethers-signers/Cargo.toml

@@ -19,7 +19,6 @@ thiserror = { version = "1.0.24", default-features = false }
 coins-bip32 = "0.3.0"
 coins-bip39 = "0.3.0"
 coins-ledger = { version = "0.3.0", default-features = false, optional = true }
-eth-keystore = { version = "0.3.0" }
 hex = { version = "0.4.3", default-features = false, features = ["std"] }
 async-trait = { version = "0.1.50", default-features = false }
 elliptic-curve = { version = "0.10.5", default-features = false }
@@ -36,14 +35,18 @@ tracing = { version = "0.1.26", optional = true }
 tracing-futures = { version = "0.2.5", optional = true }
 spki = { version = "0.4.0", optional = true }
 
+[target.'cfg(not(target_arch = "wasm32"))'.dependencies]
+eth-keystore = { version = "0.3.0" }
+
 [dev-dependencies]
 ethers = { version = "0.4.0", path = ".." }
+tracing-subscriber = "0.2.20"
 yubihsm = { version = "0.39.0", features = ["secp256k1", "usb", "mockhsm"] }
 
-tempfile = "3.2.0"
+[target.'cfg(not(target_arch = "wasm32"))'.dev-dependencies]
+yubihsm = { version = "0.39.0", features = ["secp256k1", "usb", "mockhsm"] }
 tokio = { version = "1.5", default-features = false, features = ["macros"] }
-
+tempfile = "3.2.0"
-tracing-subscriber = "0.2.20"
 
 [features]
 celo = ["ethers-core/celo"]

ethers-signers/src/ledger/mod.rs

@@ -7,7 +7,8 @@ use async_trait::async_trait;
 use ethers_core::types::{transaction::eip2718::TypedTransaction, Address, Signature};
 use types::LedgerError;
 
-#[async_trait]
+#[cfg_attr(target_arch = "wasm32", async_trait(?Send))]
+#[cfg_attr(not(target_arch = "wasm32"), async_trait)]
 impl Signer for LedgerEthereum {
     type Error = LedgerError;
 

ethers-signers/src/lib.rs

@@ -81,7 +81,8 @@ pub fn to_eip155_v<T: Into<u8>>(recovery_id: T, chain_id: u64) -> u64 {
 /// Trait for signing transactions and messages
 ///
 /// Implement this trait to support different signing modes, e.g. Ledger, hosted etc.
-#[async_trait]
+#[cfg_attr(target_arch = "wasm32", async_trait(?Send))]
+#[cfg_attr(not(target_arch = "wasm32"), async_trait)]
 pub trait Signer: std::fmt::Debug + Send + Sync {
     type Error: Error + Send + Sync;
     /// Signs the hash of the provided message after prefixing it

ethers-signers/src/wallet/mnemonic.rs

@@ -189,6 +189,7 @@ impl<W: Wordlist> MnemonicBuilder<W> {
 }
 
 #[cfg(test)]
+#[cfg(not(target_arch = "wasm32"))]
 mod tests {
     use super::*;
 

ethers-signers/src/wallet/mod.rs

@@ -64,7 +64,8 @@ pub struct Wallet<D: DigestSigner<Sha256Proxy, RecoverableSignature>> {
     pub(crate) chain_id: u64,
 }
 
-#[async_trait]
+#[cfg_attr(target_arch = "wasm32", async_trait(?Send))]
+#[cfg_attr(not(target_arch = "wasm32"), async_trait)]
 impl<D: Sync + Send + DigestSigner<Sha256Proxy, RecoverableSignature>> Signer for Wallet<D> {
     type Error = std::convert::Infallible;
 

ethers-signers/src/wallet/private_key.rs

@@ -4,14 +4,18 @@ use super::Wallet;
 use crate::wallet::mnemonic::MnemonicBuilderError;
 use coins_bip32::Bip32Error;
 use coins_bip39::MnemonicError;
+#[cfg(not(target_arch = "wasm32"))]
 use elliptic_curve::rand_core;
+#[cfg(not(target_arch = "wasm32"))]
 use eth_keystore::KeystoreError;
 use ethers_core::{
     k256::ecdsa::{self, SigningKey},
     rand::{CryptoRng, Rng},
     utils::secret_key_to_address,
 };
-use std::{path::Path, str::FromStr};
+#[cfg(not(target_arch = "wasm32"))]
+use std::path::Path;
+use std::str::FromStr;
 use thiserror::Error;
 
 #[derive(Error, Debug)]
@@ -24,6 +28,7 @@ pub enum WalletError {
     #[error(transparent)]
     Bip39Error(#[from] MnemonicError),
     /// Underlying eth keystore error
+    #[cfg(not(target_arch = "wasm32"))]
     #[error(transparent)]
     EthKeystoreError(#[from] KeystoreError),
     /// Error propagated from k256's ECDSA module
@@ -54,6 +59,7 @@ impl Clone for Wallet<SigningKey> {
 impl Wallet<SigningKey> {
     /// Creates a new random encrypted JSON with the provided password and stores it in the
     /// provided directory
+    #[cfg(not(target_arch = "wasm32"))]
     pub fn new_keystore<P, R, S>(dir: P, rng: &mut R, password: S) -> Result<Self, WalletError>
     where
         P: AsRef<Path>,
@@ -71,6 +77,7 @@ impl Wallet<SigningKey> {
     }
 
     /// Decrypts an encrypted JSON from the provided path to construct a Wallet instance
+    #[cfg(not(target_arch = "wasm32"))]
     pub fn decrypt_keystore<P, S>(keypath: P, password: S) -> Result<Self, WalletError>
     where
         P: AsRef<Path>,
@@ -145,6 +152,7 @@ impl FromStr for Wallet<SigningKey> {
 }
 
 #[cfg(test)]
+#[cfg(not(target_arch = "wasm32"))]
 mod tests {
     use super::*;
     use crate::Signer;

ethers-signers/src/wallet/yubi.rs

@@ -64,6 +64,7 @@ impl From<YubiSigner<Secp256k1>> for Wallet<YubiSigner<Secp256k1>> {
 }
 
 #[cfg(test)]
+#[cfg(not(target_arch = "wasm32"))]
 mod tests {
     use super::*;
     use crate::Signer;

examples/ethers-wasm/.gitignore

@@ -0,0 +1,8 @@
+/target
+**/*.rs.bk
+Cargo.lock
+bin/
+pkg/
+wasm-pack.log
+node_modules/
+yarn-error.log

examples/ethers-wasm/Cargo.toml

@@ -0,0 +1,52 @@
+[package]
+name = "ethers-wasm"
+version = "0.1.0"
+authors = ["Matthias Seitz <matthias.seitz@outlook.de>"]
+edition = "2018"
+license = "MIT OR Apache-2.0"
+readme = "README.md"
+documentation = "https://docs.rs/ethers"
+repository = "https://github.com/gakonst/ethers-rs"
+homepage = "https://docs.rs/ethers"
+description = """
+How to use ethers in the browser with WASM.
+"""
+
+[lib]
+crate-type = ["cdylib", "rlib"]
+
+[features]
+default = ["console_error_panic_hook"]
+
+[dependencies]
+ethers = { path = "../..", features = ["abigen", "legacy", "ws"] }
+serde_derive = "1.0.126"
+wasm-bindgen-futures = "0.4.24"
+serde_json = "1.0.64"
+wasm-bindgen = { version = "0.2.74", features = ["serde-serialize"] }
+
+# 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 = "0.1.6", optional = true }
+
+# `wee_alloc` is a tiny allocator for wasm that is only ~1K in code size
+# compared to the default allocator's ~10K. It is slower than the default
+# allocator, however.
+#
+# Unfortunately, `wee_alloc` requires nightly Rust when targeting wasm for now.
+wee_alloc = { version = "0.4.5", optional = true }
+
+serde = { version = "1.0.126", features = ["derive"] }
+hex = "0.4.3"
+web-sys = "0.3.51"
+
+[dev-dependencies]
+wasm-bindgen-test = "0.3.24"
+
+# profile for the wasm example
+[profile.release.package.ethers-wasm]
+# Tell `rustc` to optimize for small code size.
+opt-level = "s"
+

examples/ethers-wasm/README.md

@@ -0,0 +1,15 @@
+## Example usage of ethers-rs from WASM
+
+Install wasm-pack with
+
+    yarn install
+
+Start a local ganache instance
+
+    yarn ganache
+
+Then you can build the example locally with:
+
+    yarn serve
+
+and then visiting http://localhost:8080 in a browser should run the example!

examples/ethers-wasm/index.html

@@ -0,0 +1,11 @@
+<!DOCTYPE html>
+<html lang="en">
+<head>
+    <meta charset="UTF-8"/>
+    <title>ethers WASM example</title>
+</head>
+<body>
+<script src="index.js"></script>
+<h1>ethers WASM</h1>
+</body>
+</html>

examples/ethers-wasm/index.js

@@ -0,0 +1,8 @@
+const ethers = import('./pkg');
+
+ethers
+    .then(m => {
+        m.setup();
+        m.deploy().catch(console.error);
+    })
+    .catch(console.error);

examples/ethers-wasm/package.json

@@ -0,0 +1,18 @@
+{
+  "name": "ethers-wasm",
+  "license": "MIT OR Apache-2.0",
+  "scripts": {
+    "build": "webpack",
+    "serve": "webpack-dev-server",
+    "ganache": "ganache-cli --blockTime 5 --seed ethers-wasm-seed"
+  },
+  "devDependencies": {
+    "@wasm-tool/wasm-pack-plugin": "1.0.1",
+    "html-webpack-plugin": "^3.2.0",
+    "text-encoding": "^0.7.0",
+    "webpack": "^4.29.4",
+    "webpack-cli": "^3.1.1",
+    "webpack-dev-server": "^3.1.0",
+    "ganache-cli": "^6.12.2"
+  }
+}

examples/ethers-wasm/src/lib.rs

@@ -0,0 +1,102 @@
+pub mod utils;
+
+use crate::utils::SIMPLECONTRACT_BIN;
+use ethers::{
+    contract::abigen,
+    prelude::{ContractFactory, LocalWallet, Provider, SignerMiddleware},
+    providers::{Middleware, Ws},
+};
+use std::sync::Arc;
+use wasm_bindgen::prelude::*;
+use web_sys::console;
+
+// When the `wee_alloc` feature is enabled, use `wee_alloc` as the global
+// allocator.
+#[cfg(feature = "wee_alloc")]
+#[global_allocator]
+static ALLOC: wee_alloc::WeeAlloc = wee_alloc::WeeAlloc::INIT;
+
+#[wasm_bindgen]
+extern "C" {
+    fn alert(s: &str);
+}
+
+macro_rules! log {
+    ( $( $t:tt )* ) => {
+        web_sys::console::log_1(&format!( $( $t )* ).into());
+    }
+}
+
+abigen!(
+    SimpleContract,
+    "./../contract_abi.json",
+    event_derives(serde::Deserialize, serde::Serialize)
+);
+
+/// key[0] of ganache with custom seed `ethers-wasm-seed`
+pub const KEY: &str = "817169e55f14ede54f4fd6a4f2ab4209db14aeeb1b9972b3b28f1560af0a061a";
+
+#[wasm_bindgen]
+pub fn setup() {
+    utils::set_panic_hook();
+}
+
+#[wasm_bindgen]
+pub async fn deploy() {
+    console::log_2(
+        &"ABI: ".into(),
+        &JsValue::from_serde(&*SIMPLECONTRACT_ABI).unwrap(),
+    );
+    let wallet: LocalWallet = KEY.parse().unwrap();
+    log!("Wallet: {:?}", wallet);
+
+    let endpoint = "ws://127.0.0.1:8545";
+    let provider = Provider::new(Ws::connect(endpoint).await.unwrap());
+    let client = Arc::new(SignerMiddleware::new(provider, wallet));
+    log!("provider connected to `{}`", endpoint);
+    let version = client.client_version().await;
+    log!("version {:?}", version);
+    let account = client.get_accounts().await.unwrap()[0];
+    log!("account {:?}", account);
+
+    let bytecode = hex::decode(SIMPLECONTRACT_BIN).unwrap();
+    let factory = ContractFactory::new(SIMPLECONTRACT_ABI.clone(), bytecode.into(), client.clone());
+    let init = "hello WASM!";
+    let contract = factory
+        .deploy(init.to_string())
+        .unwrap()
+        .send()
+        .await
+        .unwrap();
+    let addr = contract.address();
+    log!("deployed contract with address {}", addr);
+
+    let contract = SimpleContract::new(addr, client.clone());
+
+    let value = contract.get_value().call().await.unwrap();
+    assert_eq!(init, &value);
+
+    let _receipt = contract
+        .set_value("bye WASM!".to_owned())
+        .send()
+        .await
+        .unwrap()
+        .await
+        .unwrap();
+    log!("set value");
+    // 10. get all events
+    let logs = contract
+        .value_changed_filter()
+        .from_block(0u64)
+        .query()
+        .await
+        .unwrap();
+
+    let value = contract.get_value().call().await.unwrap();
+
+    log!(
+        "Value: {}. Logs: {:?}",
+        value,
+        JsValue::from_serde(&logs).unwrap()
+    );
+}

examples/ethers-wasm/src/utils.rs

@@ -0,0 +1,12 @@
+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();
+}
+
+pub const SIMPLECONTRACT_BIN: &str = "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";

examples/ethers-wasm/tests/contract_with_abi.rs

@@ -0,0 +1,71 @@
+//! Test suite for the Web and headless browsers.
+
+#![cfg(target_arch = "wasm32")]
+
+use wasm_bindgen::prelude::*;
+use wasm_bindgen_test::*;
+
+use ethers::{
+    contract::abigen,
+    prelude::{ContractFactory, LocalWallet, Provider, SignerMiddleware},
+    providers::Ws,
+};
+
+use std::sync::Arc;
+
+wasm_bindgen_test_configure!(run_in_browser);
+
+// Generate the type-safe contract bindings by providing the ABI
+// definition in human readable format
+abigen!(
+    SimpleContract,
+    "../contract_abi.json",
+    event_derives(serde::Deserialize, serde::Serialize)
+);
+
+#[wasm_bindgen_test]
+async fn connect_and_deploy() {
+    console_log!("starting");
+
+    // a private key of a launched ganache `yarn ganache`
+    let wallet: LocalWallet = ethers_wasm::KEY.parse().unwrap();
+
+    let provider = Provider::new(Ws::connect("ws://localhost:8545").await.unwrap());
+    let client = Arc::new(SignerMiddleware::new(provider, wallet));
+
+    let bytecode = hex::decode(ethers_wasm::utils::SIMPLECONTRACT_BIN).unwrap();
+    let factory = ContractFactory::new(SIMPLECONTRACT_ABI.clone(), bytecode.into(), client.clone());
+    let contract = factory
+        .deploy("initial value".to_string())
+        .unwrap()
+        .send()
+        .await
+        .unwrap();
+    let addr = contract.address();
+    console_log!("deployed to {}", addr);
+
+    let contract = SimpleContract::new(addr, client.clone());
+    let _receipt = contract
+        .set_value("hi".to_owned())
+        .send()
+        .await
+        .unwrap()
+        .await
+        .unwrap();
+
+    //  get all events
+    let logs = contract
+        .value_changed_filter()
+        .from_block(0u64)
+        .query()
+        .await
+        .unwrap();
+
+    let value = contract.get_value().call().await.unwrap();
+
+    console_log!(
+        "Value: {}. Logs: {:?}",
+        value,
+        JsValue::from_serde(&logs).unwrap()
+    );
+}

examples/ethers-wasm/webpack.config.js

@@ -0,0 +1,28 @@
+const path = require('path');
+const HtmlWebpackPlugin = require('html-webpack-plugin');
+const webpack = require('webpack');
+const WasmPackPlugin = require("@wasm-tool/wasm-pack-plugin");
+
+module.exports = {
+    entry: './index.js',
+    output: {
+        path: path.resolve(__dirname, 'dist'),
+        filename: 'index.js',
+    },
+    plugins: [
+        new HtmlWebpackPlugin({
+                template: './index.html'
+            }
+        ),
+        new WasmPackPlugin({
+            crateDirectory: path.resolve(__dirname, ".")
+        }),
+        // Have this example work in Edge which doesn't ship `TextEncoder` or
+        // `TextDecoder` at this time.
+        new webpack.ProvidePlugin({
+            TextDecoder: ['text-encoding', 'TextDecoder'],
+            TextEncoder: ['text-encoding', 'TextEncoder']
+        })
+    ],
+    mode: 'development'
+};