feat: BYOB streams, basic usage, _pending WPT_

Author: Guy Bedford

c-dependencies/spidermonkey

@@ -0,0 +1,120 @@
+/* eslint-env serviceworker */
+/* global fastly */
+function strictEqual (a, b) {
+  if (a !== b) {
+    console.log('LHS: ', a);
+    console.log('RHS: ', b);
+    throw new Error(`Assertion failure`);
+  }
+}
+
+addEventListener("fetch", async (event) => {
+  let cnt = 0;
+  const stream = new ReadableStream({
+    // type: 'bytes',
+    pull (controller) {
+      cnt++;
+      const view = controller.byobRequest?.view;
+      if (view) {
+        view[0] = 104;
+        view[1] = 101;
+        view[2] = 121;
+        controller.byobRequest.respond(3);
+      } else {
+        controller.enqueue(new Uint8Array([104, 101, 106]));
+      }
+      if (cnt === 3)
+        return controller.close();
+    }
+  });
+  event.respondWith(new Response(stream));
+
+  {
+    let cnt = 0;
+    const stream = new ReadableStream({
+      type: 'bytes',
+      autoAllocateChunkSize: 1024,
+      start (controller) {
+      },
+      pull (controller) {
+        cnt++;
+        const view = controller.byobRequest?.view;
+        if (cnt < 3) {
+          view[0] = 1;
+          view[1] = 2;
+          view[2] = 3;
+          controller.byobRequest.respond(3);
+        } else if (cnt == 3) {
+          controller.enqueue(new Uint8Array([1,2,4]));
+        }
+        if (cnt === 3)
+          return controller.close();
+      }
+    });
+  
+    const byobReader = stream.getReader();
+    let buf;
+    let result;
+    let offset = 0;
+    while (true) {
+      if (buf && cnt < 3) {
+        const output = new Uint8Array(buf);
+        strictEqual(output[0], 1);
+        strictEqual(output[1], 2);
+        strictEqual(output[2], 3);
+        strictEqual(output[3], 0);
+        strictEqual(output.byteLength, 1024);
+      }
+      result = await byobReader.read();
+      if (result.done)
+        break;
+      offset += result.value.byteLength;
+      buf = result.value.buffer;
+    }
+
+    strictEqual(cnt, 3);
+    const output = new Uint8Array(buf);
+    strictEqual(output[0], 1);
+    strictEqual(output[1], 2);
+    strictEqual(output[2], 4);
+    strictEqual(output[3], undefined);
+    strictEqual(output.byteLength, 3);
+    console.log('Passed 1');
+  }
+
+  {
+    let cnt = 0;
+    const stream = new ReadableStream({
+      type: 'bytes',
+      start (controller) {
+      },
+      pull (controller) {
+        cnt++;
+        const view = controller.byobRequest?.view;
+        if (view) {
+          view[0] = 1;
+          view[1] = 2;
+          view[2] = 3;
+          controller.byobRequest.respond(3);
+        }
+        if (cnt === 3)
+          return controller.close();
+      }
+    });
+  
+    const byobReader = stream.getReader({ mode: 'byob' });
+    let buf = new ArrayBuffer(10);
+    let result;
+    let offset = 0;
+    do {
+      result = await byobReader.read(new Uint8Array(buf, offset));
+      offset += result.value.byteLength;
+      buf = result.value.buffer;
+    } while(!result.done);
+  
+    const out = new Uint8Array(buf);
+    if (out[0] === 1 && out[1] === 2 && out[2] === 3 && out[3] === 1 && out[4] === 2 && out[5] === 3 && out[6] === 1 && out[7] === 2 && out[8] === 3) {
+        console.log('Passed 2');
+    }
+  }
+});

integration-tests/js-compute/fixtures/byob/bin/index.js

@@ -0,0 +1,12 @@
+# This file describes a Fastly Compute@Edge package. To learn more visit:
+# https://developer.fastly.com/reference/fastly-toml/
+
+authors = ["[email protected]"]
+description = ""
+language = "other"
+manifest_version = 2
+name = "console"
+service_id = ""
+
+[scripts]
+  build = "node ../../../../js-compute-runtime-cli.js"

integration-tests/js-compute/fixtures/byob/fastly.toml.in

@@ -0,0 +1,17 @@
+{
+  "GET /": {
+    "environments": ["viceroy"],
+    "downstream_request": {
+      "method": "GET",
+      "pathname": "/"
+    },
+    "downstream_response": {
+      "status": 200,
+      "body": "heyheyhey"
+    },
+    "logs": [
+      "stdout :: Log: Passed 1",
+      "stdout :: Log: Passed 2"
+    ]
+  }
+}

integration-tests/js-compute/fixtures/byob/tests.json

@@ -31,7 +31,8 @@
     "test": "npm run test:types && npm run test:cli",
     "test:cli": "brittle --bail integration-tests/cli/**.test.js",
     "test:types": "tsd",
-    "build": "make -j8 -C c-dependencies/js-compute-runtime && cp c-dependencies/js-compute-runtime/*.wasm c-dependencies/js-compute-runtime/fastly.wit ."
+    "build": "make -j8 -C c-dependencies/js-compute-runtime && cp c-dependencies/js-compute-runtime/*.wasm c-dependencies/js-compute-runtime/fastly.wit .",
+    "build:debug": "DEBUG=true make -j8 -C c-dependencies/js-compute-runtime && cp c-dependencies/js-compute-runtime/*.wasm c-dependencies/js-compute-runtime/fastly.wit ."
   },
   "devDependencies": {
     "@jakechampion/cli-testing-library": "^1.0.0",

package.json

@@ -4,6 +4,7 @@ set -euo pipefail
 
 cd "$(dirname "${BASH_SOURCE[0]}")"
 root="$(pwd)"
+mode=${MODE:-release}
 
 if [ "$#" -lt 1 ]; then
     echo "Usage: $0 <application_name>"
@@ -22,10 +23,27 @@ if [ ! -d $application_path ]; then
     exit 1
 fi
 
+case "$mode" in
+  release)
+    yarn build
+    (
+        cd $application_path
+        ../../replace-host.sh $application_name "https://compute-sdk-test-backend.edgecompute.app"
+        fastly compute serve --quiet
+    )
+    ;;
 
-yarn build
-(
-    cd $application_path
-    ../../replace-host.sh $application_name "https://compute-sdk-test-backend.edgecompute.app"
-    fastly compute serve --quiet
-)
+  debug)
+    yarn build:debug
+    (
+        cd $application_path
+        ../../replace-host.sh $application_name "https://compute-sdk-test-backend.edgecompute.app"
+        fastly compute serve --verbose
+    )
+    ;;
+
+  *)
+    echo "Unknown build type: $mode"
+    exit 1
+    ;;
+esac