[PoC] WebAssembly Runner

Dockerfile

@@ -1,36 +1,48 @@
-FROM node:lts-slim as node
-
-WORKDIR /build
-
-ARG FONTAWESOME_TOKEN
-COPY package*.json ./
-RUN echo "@fortawesome:registry=https://npm.fontawesome.com/\n//npm.fontawesome.com/:_authToken=${FONTAWESOME_TOKEN}" > ./.npmrc \
-    && npm ci \
-    && rm -f ./.npmrc
-
-COPY webpack.*.js ./
-COPY Public ./Public/
-RUN npx webpack --config webpack.prod.js
-
-
 FROM swiftlang/swift:nightly-main-focal as swift
 RUN export DEBIAN_FRONTEND=noninteractive DEBCONF_NONINTERACTIVE_SEEN=true \
     && apt-get -q update && apt-get -q dist-upgrade -y \
-    && apt-get install -y --no-install-recommends libsqlite3-dev \
+    && apt-get install -y --no-install-recommends libsqlite3-dev curl \
     && rm -rf /var/lib/apt/lists/*
 
+RUN set -e; \
+    SWIFT_PLATFORM_SUFFIX="ubuntu20.04_x86_64.tar.gz" \
+    SWIFTWASM_TAG=swift-wasm-5.7-SNAPSHOT-2022-06-25-a \
+    SWIFTWASM_BIN_URL="https://github.com/swiftwasm/swift/releases/download/$SWIFTWASM_TAG/$SWIFTWASM_TAG-$SWIFT_PLATFORM_SUFFIX" \
+    && export DEBIAN_FRONTEND=noninteractive \
+    && curl -fsSL "$SWIFTWASM_BIN_URL" -o swiftwasm.tar.gz \
+    && mkdir -p /opt/swiftwasm \
+    && tar -xzf swiftwasm.tar.gz --directory /opt/swiftwasm --strip-components=1 \
+    && chmod -R o+r /opt/swiftwasm/usr/lib/swift \
+    && rm -rf swiftwasm.tar.gz
+
 WORKDIR /build
-COPY --from=node /build /build
 COPY ./Package.* ./
 RUN swift package resolve
 
 COPY . .
 RUN swift build -c release -Xswiftc -enable-testing
+RUN SWIFTWASM_TOOLCHAIN=/opt/swiftwasm ./Scripts/build-wasm.sh
 
 WORKDIR /staging
 RUN cp "$(swift build --package-path /build -c release --show-bin-path)/Run" ./ \
     && mv /build/Public ./Public && chmod -R a-w ./Public \
-    && mv /build/.build ./.build && chmod -R a-w ./.build
+    && cp -R /build/.build ./.build && chmod -R a-w ./.build
+
+FROM node:lts-slim as node
+
+WORKDIR /build
+
+ARG FONTAWESOME_TOKEN
+COPY package*.json ./
+RUN echo "@fortawesome:registry=https://npm.fontawesome.com/\n//npm.fontawesome.com/:_authToken=${FONTAWESOME_TOKEN}" > ./.npmrc \
+    && npm ci \
+    && rm -f ./.npmrc
+
+COPY webpack.*.js ./
+COPY Public ./Public/
+COPY --from=swift /staging/.build/wasm .build/wasm
+RUN npx webpack --config webpack.prod.js
+
 
 
 FROM swiftlang/swift:nightly-main-focal
@@ -40,10 +52,11 @@ RUN export DEBIAN_FRONTEND=noninteractive DEBCONF_NONINTERACTIVE_SEEN=true \
 
 WORKDIR /app
 COPY --from=swift --chown=vapor:vapor /staging /app
+COPY --from=node /build/Public/dist /app/Public/dist
 
 USER vapor:vapor
 EXPOSE 8080
 
 ENTRYPOINT ["./Run"]
 CMD ["serve", "--env", "production", "--hostname", "0.0.0.0", "--port", "8080"]
-
+

Package.swift

@@ -7,7 +7,7 @@ let package = Package(
         .macOS(.v12)
     ],
     dependencies: [
-        .package(url: "https://github.com/apple/swift-experimental-string-processing.git", branch: "main"),
+        .package(url: "https://github.com/apple/swift-experimental-string-processing.git", branch: "cff565f296580bbb966bb7e35b65e9a8e184abbb"),
         .package(url: "https://github.com/apple/swift-syntax", branch: "main"),
         .package(url: "https://github.com/vapor/vapor.git", from: "4.65.0"),
         .package(url: "https://github.com/vapor/leaf.git", from: "4.2.0"),

Public/js/app.js

@@ -10,7 +10,7 @@ import { MatchInfoView } from "./views/match_info_view";
 
 import { DSLHighlighter } from "./views/dsl_highlighter";
 
-import { Runner } from "./runner";
+import { WasmRunner } from "./wasm_runner";
 
 export class App {
   constructor() {
@@ -81,7 +81,7 @@ export class App {
       this.onDSLEditorChange();
     });
 
-    this.runner = new Runner();
+    this.runner = new WasmRunner();
     this.runner.onready = this.onRunnerReady.bind(this);
     this.runner.onresponse = this.onRunnerResponse.bind(this);
 

Public/js/wasm_runner.js

@@ -0,0 +1,120 @@
+"use strict";
+
+import { Runner } from "./runner";
+import { WASI } from "@wasmer/wasi";
+import { WasmFs } from "@wasmer/wasmfs";
+
+class WASICommand {
+  constructor(wasmModule) {
+    this.wasmModule = wasmModule;
+  }
+
+  static async load(wasmFile) {
+    const response = await fetch(wasmFile)
+    if (WebAssembly.compileStreaming) {
+      const wasmModule = await WebAssembly.compileStreaming(response);
+      return new WASICommand(wasmModule);
+    } else {
+      const bytes = await response.arrayBuffer();
+      const wasmModule = await WebAssembly.compile(bytes);
+      return new WASICommand(wasmModule);
+    }
+  }
+
+  async exec(args) {
+    const wasmFs = new WasmFs();
+    let stdout = "";
+    let stderr = "";
+    const originalWriteSync = wasmFs.fs.writeSync;
+    wasmFs.fs.writeSync = (fd, buffer, offset, length, position) => {
+      const text = new TextDecoder("utf-8").decode(buffer);
+      switch (fd) {
+        case 1:
+          stdout += text;
+          break;
+        case 2:
+          stderr += text;
+          console.error(text);
+          break;
+      }
+      return originalWriteSync(fd, buffer, offset, length, position);
+    };
+
+    const wrapWASI = (wasiObject) => {
+      // PATCH: @wasmer-js/wasi@0.x forgets to call `refreshMemory` in `clock_res_get`,
+      // See also https://github.com/swiftwasm/carton/blob/2c5cf34e0cbb6a4807445ef62a8404bac40314b1/entrypoint/common.js#L135-L145
+      const original_clock_res_get = wasiObject.wasiImport["clock_res_get"];
+
+      wasiObject.wasiImport["clock_res_get"] = (clockId, resolution) => {
+        wasiObject.refreshMemory();
+        return original_clock_res_get(clockId, resolution);
+      };
+      return wasiObject.wasiImport;
+    };
+    const wasi = new WASI({
+      args: ["main.wasm", ...args],
+      bindings: {
+        ...WASI.defaultBindings,
+        fs: wasmFs.fs,
+      },
+    });
+    const instance = await WebAssembly.instantiate(this.wasmModule, {
+      wasi_snapshot_preview1: wrapWASI(wasi),
+    });
+    wasi.start(instance);
+    return { stdout, stderr };
+  }
+}
+
+export class WasmRunner extends Runner {
+  constructor() {
+    super();
+
+    this.locallyAvailableMethods = {
+      "parseDSL": {
+        command: WASICommand.load("./DSLParser.wasm"),
+        async run(request, command) {
+          const { stdout, stderr } =  await command.exec([request.pattern])
+          return { method: request.method, result: stdout, error: stderr };
+        }
+      },
+      "convertToDSL": {
+        command: WASICommand.load("./DSLConverter.wasm"),
+        async run(request, command) {
+          const { stdout, stderr } =  await command.exec([request.pattern])
+          return { method: request.method, result: stdout, error: stderr };
+        }
+      },
+      "match": {
+        command: WASICommand.load("./Matcher.wasm"),
+        async run(request, command) {
+          const { stdout, stderr } =  await command.exec([request.pattern, request.text, request.matchOptions.join(",")])
+          return { method: request.method, result: stdout, error: stderr };
+        }
+      },
+      "parseExpression": {
+        command: WASICommand.load("./ExpressionParser.wasm"),
+        async run(request, command) {
+          const { stdout, stderr } =  await command.exec([request.pattern, request.matchOptions.join(",")])
+          return { method: request.method, result: stdout, error: stderr };
+        }
+      },
+    }
+  }
+  async run(request) {
+    if (this.locallyAvailableMethods[request.method]) {
+      try {
+        const method = this.locallyAvailableMethods[request.method];
+        const command = await method.command;
+        const response = await method.run(request, command);
+        console.log(response);
+        this.onresponse(response);
+      } catch (e) {
+        console.warn(`Error while running ${request.method} on local. Retry on backend:`, e);
+        super.run(request);
+      }
+      return;
+    }
+    super.run(request);
+  }
+}

Scripts/build-wasm.sh

@@ -0,0 +1,19 @@
+set -eu
+
+SWIFTWASM_TOOLCHAIN="${SWIFTWASM_TOOLCHAIN:?"Install SwiftWasm toolchain snapshot https://github.com/swiftwasm/swift/releases/tag/swift-wasm-5.7-SNAPSHOT-2022-06-25-a"}"
+
+for product in "DSLParser" "DSLConverter" "Matcher" "ExpressionParser"; do
+    echo "Building ${product} for WebAssembly..."
+    # WORKAROUND: --disable-dead-strip is required to avoid using --gc-sections in linking
+    # since wasm-ld doesn't support retaining dynamically referenced data segment yet
+    # See also:
+    # * https://github.com/llvm/llvm-project/issues/55839
+    # * https://github.com/apple/swift-package-manager/pull/4135
+    $SWIFTWASM_TOOLCHAIN/usr/bin/swift build \
+        --triple wasm32-unknown-wasi \
+        --scratch-path .build/wasm \
+        --configuration release \
+        -Xswiftc -enable-testing \
+        --disable-dead-strip \
+        --product "$product"
+done