lib,src: implement WebAssembly Web API

Refs: https://github.com/nodejs/node/pull/41749
Fixes: https://github.com/nodejs/node/issues/21130

PR-URL: https://github.com/nodejs/node/pull/42701
Reviewed-By: Gus Caplan <me@gus.host>
Reviewed-By: Antoine du Hamel <duhamelantoine1995@gmail.com>

2 files changed, 45 insertions, 1 deletions

diff --git a/lib/internal/bootstrap/pre_execution.js b/lib/internal/bootstrap/pre_execution.js
index b64dfaf980f..e1b882b6dbe 100644
--- a/lib/internal/bootstrap/pre_execution.js
+++ b/lib/internal/bootstrap/pre_execution.js
@@ -5,6 +5,7 @@ const {
   ObjectDefineProperties,
   ObjectDefineProperty,
   ObjectGetOwnPropertyDescriptor,
+  PromiseResolve,
   SafeMap,
   SafeWeakMap,
   StringPrototypeStartsWith,
@@ -24,7 +25,11 @@ const {
 } = require('internal/util');
 
 const { Buffer } = require('buffer');
-const { ERR_MANIFEST_ASSERT_INTEGRITY } = require('internal/errors').codes;
+const {
+  ERR_INVALID_ARG_TYPE,
+  ERR_MANIFEST_ASSERT_INTEGRITY,
+  ERR_WEBASSEMBLY_RESPONSE,
+} = require('internal/errors').codes;
 const assert = require('internal/assert');
 
 function prepareMainThreadExecution(expandArgv1 = false,
@@ -215,6 +220,44 @@ function setupFetch() {
     Request: lazyInterface('Request'),
     Response: lazyInterface('Response'),
   });
+
+  // The WebAssembly Web API: https://webassembly.github.io/spec/web-api
+  internalBinding('wasm_web_api').setImplementation((streamState, source) => {
+    (async () => {
+      const response = await PromiseResolve(source);
+      if (!(response instanceof lazyUndici().Response)) {
+        throw new ERR_INVALID_ARG_TYPE(
+          'source', ['Response', 'Promise resolving to Response'], response);
+      }
+
+      const contentType = response.headers.get('Content-Type');
+      if (contentType !== 'application/wasm') {
+        throw new ERR_WEBASSEMBLY_RESPONSE(
+          `has unsupported MIME type '${contentType}'`);
+      }
+
+      if (!response.ok) {
+        throw new ERR_WEBASSEMBLY_RESPONSE(
+          `has status code ${response.status}`);
+      }
+
+      if (response.bodyUsed !== false) {
+        throw new ERR_WEBASSEMBLY_RESPONSE('body has already been used');
+      }
+
+      // Pass all data from the response body to the WebAssembly compiler.
+      for await (const chunk of response.body) {
+        streamState.push(chunk);
+      }
+    })().then(() => {
+      // No error occurred. Tell the implementation that the stream has ended.
+      streamState.finish();
+    }, (err) => {
+      // An error occurred, either because the given object was not a valid
+      // and usable Response or because a network error occurred.
+      streamState.abort(err);
+    });
+  });
 }
 
 // TODO(aduh95): move this to internal/bootstrap/browser when the CLI flag is
diff --git a/lib/internal/errors.js b/lib/internal/errors.js
index 1dfa36e5f36..d5bb5023a79 100644
--- a/lib/internal/errors.js
+++ b/lib/internal/errors.js
@@ -1659,6 +1659,7 @@ E('ERR_VM_MODULE_NOT_MODULE',
   'Provided module is not an instance of Module', Error);
 E('ERR_VM_MODULE_STATUS', 'Module status %s', Error);
 E('ERR_WASI_ALREADY_STARTED', 'WASI instance has already started', Error);
+E('ERR_WEBASSEMBLY_RESPONSE', 'WebAssembly response %s', TypeError);
 E('ERR_WORKER_INIT_FAILED', 'Worker initialization failure: %s', Error);
 E('ERR_WORKER_INVALID_EXEC_ARGV', (errors, msg = 'invalid execArgv flags') =>
   `Initiated Worker with ${msg}: ${ArrayPrototypeJoin(errors, ', ')}`,