fix(api/fetch): improve streaming

Author: jwerle

api/fetch/fetch.js

@@ -393,7 +393,7 @@ export function Request(input, options) {
   if ((this.method === 'GET' || this.method === 'HEAD') && body) {
     throw new TypeError('Body not allowed for GET or HEAD requests')
   }
-  this._initBody(body)
+  this._initBody(body, options)
 
   if (this.method === 'GET' || this.method === 'HEAD') {
     if (options.cache === 'no-store' || options.cache === 'no-cache') {
@@ -478,7 +478,7 @@ export function Response(bodyInit, options) {
   this.statusText = options.statusText === undefined ? '' : '' + options.statusText
   this.headers = new Headers(options.headers)
   this.url = options.url || ''
-  this._initBody(bodyInit)
+  this._initBody(bodyInit, options)
 }
 
 Body.call(Response.prototype)
@@ -575,6 +575,10 @@ export function fetch(input, init) {
       }, 0)
     }
 
+    if (init?.onxhr) {
+      init.onxhr(xhr)
+    }
+
     function fixUrl(url) {
       try {
         return url === '' && g.location.href ? g.location.href : url

api/fetch/index.js

@@ -97,24 +97,50 @@ async function initBody (body) {
     if (this._bodyArrayBuffer) {
       const arrayBuffer = this._bodyArrayBuffer
       this.body = new ReadableStream({
-        start (controller) {
+        async start (controller) {
           controller.enqueue(arrayBuffer)
           controller.close()
         }
       })
     } else if (this._bodyBlob) {
       const blob = this._bodyBlob
       this.body = new ReadableStream({
+        type: 'bytes',
         async start (controller) {
-          controller.enqueue(await blob.arrayBuffer())
+          const stream = await blob.stream()
+          if (controller.byobRequest) {
+            const reader = stream.getReader({ mode: 'byob' })
+            while (true) {
+              const { done, value } = await reader.read(controller.byobRequest.view)
+              if (done) {
+                break
+              }
+
+              if (value?.byteLength > 0) {
+                controller.byobRequest.respond(value.byteLength)
+              }
+            }
+          } else {
+            const reader = stream.getReader()
+            while (true) {
+              const { done, value } = await reader.read()
+              if (done) {
+                break
+              }
+
+              controller.enqueue(value)
+            }
+          }
+
           controller.close()
         }
       })
     } else if (this._bodyText) {
       const text = this._bodyText
+      const encoded = textEncoder.encode(text)
       this.body = new ReadableStream({
-        start (controller) {
-          controller.enqueue(textEncoder.encode(text))
+        async start (controller) {
+          controller.enqueue(encoded)
           controller.close()
         }
       })