move Accept header to FormSubmission

src/core/drive/form_submission.ts

@@ -78,7 +78,7 @@ export class FormSubmission {
   // Fetch request delegate
 
   additionalHeadersForRequest(request: FetchRequest) {
-    const headers: FetchRequestHeaders = {}
+    const headers: FetchRequestHeaders = { Accept: "text/html; turbo-stream" }
     if (this.method != FetchMethod.get) {
       const token = getCookieValue(getMetaContent("csrf-param")) || getMetaContent("csrf-token")
       if (token) {

src/observers/stream_observer.ts

@@ -1,4 +1,3 @@
-import { FormSubmission } from "../core/drive/form_submission"
 import { FetchResponse } from "../http/fetch_response"
 import { StreamMessage } from "../core/streams/stream_message"
 import { StreamSource } from "../core/types"
@@ -19,16 +18,12 @@ export class StreamObserver {
   start() {
     if (!this.started) {
       this.started = true
-      addEventListener("turbo:submit-start", this.prepareFormSubmission, true)
-      addEventListener("turbo:before-fetch-response", this.inspectFetchResponse, false)
     }
   }
 
   stop() {
     if (this.started) {
       this.started = false
-      removeEventListener("turbo:submit-start", this.prepareFormSubmission, true)
-      removeEventListener("turbo:before-fetch-response", this.inspectFetchResponse, false)
     }
   }
 
@@ -50,23 +45,6 @@ export class StreamObserver {
     return this.sources.has(source)
   }
 
-  prepareFormSubmission = <EventListener>((event: CustomEvent) => {
-    const formSubmission: FormSubmission = event.detail?.formSubmission
-    const headers: any = formSubmission.fetchRequest.fetchOptions.headers
-
-    if (headers) {
-      headers.Accept = [ "text/html; turbo-stream", headers.Accept ].join(", ")
-    }
-  })
-
-  inspectFetchResponse = <EventListener>((event: CustomEvent) => {
-    const response = fetchResponseFromEvent(event)
-    if (response && fetchResponseIsStream(response)) {
-      event.preventDefault()
-      this.receiveMessageResponse(response)
-    }
-  })
-
   receiveMessageEvent = (event: MessageEvent) => {
     if (this.started && typeof event.data == "string") {
       this.receiveMessageHTML(event.data)
@@ -84,15 +62,3 @@ export class StreamObserver {
     this.delegate.receivedMessageFromStream(new StreamMessage(html))
   }
 }
-
-function fetchResponseFromEvent(event: CustomEvent) {
-  const fetchResponse = event.detail?.fetchResponse
-  if (fetchResponse instanceof FetchResponse) {
-    return fetchResponse
-  }
-}
-
-function fetchResponseIsStream(response: FetchResponse) {
-  const contentType = response.contentType ?? ""
-  return /text\/html;.*\bturbo-stream\b/.test(contentType)
-}