Move dns_instrument from onCompleted to onHeadersReceived

Author: englehardt

Extension/src/background/dns-instrument.ts

@@ -1,12 +1,12 @@
 import { PendingResponse } from "../lib/pending-response";
 import { DnsResolved } from "../schema";
-import { WebRequestOnCompletedEventDetails } from "../types/browser-web-request-event-details";
+import { WebRequestOnHeadersReceivedDetails } from "../types/browser-web-request-event-details";
 import { allTypes } from "./http-instrument";
 import RequestFilter = browser.webRequest.RequestFilter;
 
 export class DnsInstrument {
   private readonly dataReceiver;
-  private onCompleteListener;
+  private onHeadersReceivedListener;
   private pendingResponses: {
     [requestId: number]: PendingResponse;
   } = {};
@@ -29,23 +29,23 @@ export class DnsInstrument {
     /*
      * Attach handlers to event listeners
      */
-    this.onCompleteListener = (details: WebRequestOnCompletedEventDetails) => {
+    this.onHeadersReceivedListener = (details: WebRequestOnHeadersReceivedDetails) => {
       // Ignore requests made by extensions
       if (requestStemsFromExtension(details)) {
         return;
       }
       const pendingResponse = this.getPendingResponse(details.requestId);
-      pendingResponse.resolveOnCompletedEventDetails(details);
+      pendingResponse.resolveOnHeadersReceivedDetails(details);
 
       this.onCompleteDnsHandler(details, crawlID);
     };
 
-    browser.webRequest.onCompleted.addListener(this.onCompleteListener, filter);
+    browser.webRequest.onHeadersReceived.addListener(this.onHeadersReceivedListener, filter);
   }
 
   public cleanup() {
-    if (this.onCompleteListener) {
-      browser.webRequest.onCompleted.removeListener(this.onCompleteListener);
+    if (this.onHeadersReceivedListener) {
+      browser.webRequest.onHeadersReceived.removeListener(this.onHeadersReceivedListener);
     }
   }
 
@@ -70,7 +70,7 @@ export class DnsInstrument {
   }
 
   private async onCompleteDnsHandler(
-    details: WebRequestOnCompletedEventDetails,
+    details: WebRequestOnHeadersReceivedDetails,
     crawlID,
   ) {
     // Create and populate DnsResolve object

Extension/src/lib/pending-response.ts

@@ -1,30 +1,40 @@
 import {
   WebRequestOnBeforeRequestEventDetails,
   WebRequestOnCompletedEventDetails,
+  WebRequestOnHeadersReceivedDetails
 } from "../types/browser-web-request-event-details";
 import { ResponseBodyListener } from "./response-body-listener";
 
 /**
- * Ties together the two separate events that together holds information about both response headers and body
+ * Ties together three separate events that hold information about both response headers and body
  */
 export class PendingResponse {
   public readonly onBeforeRequestEventDetails: Promise<
     WebRequestOnBeforeRequestEventDetails
   >;
+  public readonly onHeadersReceivedEventDetails: Promise<
+  WebRequestOnHeadersReceivedDetails
+  >;
   public readonly onCompletedEventDetails: Promise<
     WebRequestOnCompletedEventDetails
   >;
   public responseBodyListener: ResponseBodyListener;
   public resolveOnBeforeRequestEventDetails: (
     details: WebRequestOnBeforeRequestEventDetails,
   ) => void;
+  public resolveOnHeadersReceivedDetails: (
+    details: WebRequestOnHeadersReceivedDetails,
+  ) => void;
   public resolveOnCompletedEventDetails: (
     details: WebRequestOnCompletedEventDetails,
   ) => void;
   constructor() {
     this.onBeforeRequestEventDetails = new Promise(resolve => {
       this.resolveOnBeforeRequestEventDetails = resolve;
     });
+    this.onHeadersReceivedEventDetails = new Promise(resolve => {
+      this.resolveOnHeadersReceivedDetails = resolve;
+    });
     this.onCompletedEventDetails = new Promise(resolve => {
       this.resolveOnCompletedEventDetails = resolve;
     });
@@ -37,6 +47,7 @@ export class PendingResponse {
   public resolved() {
     return Promise.all([
       this.onBeforeRequestEventDetails,
+      this.onHeadersReceivedEventDetails,
       this.onCompletedEventDetails,
     ]);
   }

Extension/src/types/browser-web-request-event-details.ts

@@ -7,6 +7,7 @@
 import ResourceType = browser.webRequest.ResourceType;
 import UploadData = browser.webRequest.UploadData;
 import HttpHeaders = browser.webRequest.HttpHeaders;
+import UrlClassification = browser.webRequest.UrlClassification;
 
 export interface FrameAncestor {
   /** The URL that the document was loaded from. */
@@ -189,3 +190,49 @@ export interface WebRequestOnCompletedEventDetails {
    */
   statusLine: string;
 }
+
+export interface WebRequestOnHeadersReceivedDetails {
+  /**
+   * The ID of the request. Request IDs are unique within a browser session. As a result, they could be used to relate different events of the same request.
+   */
+  requestId: string;
+  url: string;
+  /** Standard HTTP method. */
+  method: string;
+  /**
+   * The value 0 indicates that the request happens in the main frame; a positive value indicates the ID of a subframe in which the request happens. If the document of a (sub-)frame is loaded (`type` is `main_frame` or `sub_frame`), `frameId` indicates the ID of this frame, not the ID of the outer frame. Frame IDs are unique within a tab.
+   */
+  frameId: number;
+  /** ID of frame that wraps the frame which sent the request. Set to -1 if no parent frame exists. */
+  parentFrameId: number;
+  /** True for private browsing requests. */
+  incognito?: boolean | undefined;
+  /** The cookie store ID of the contextual identity. */
+  cookieStoreId?: string | undefined;
+  /** URL of the resource that triggered this request. */
+  originUrl?: string | undefined;
+  /** URL of the page into which the requested resource will be loaded. */
+  documentUrl?: string | undefined;
+  /** The ID of the tab in which the request takes place. Set to -1 if the request isn't related to a tab. */
+  tabId: number;
+  /** How the requested resource will be used. */
+  type: ResourceType;
+  /** The time when this signal is triggered, in milliseconds since the epoch. */
+  timeStamp: number;
+  /**
+   * HTTP status line of the response or the 'HTTP/0.9 200 OK' string for HTTP/0.9 responses (i.e., responses that lack a status line).
+   */
+  statusLine: string;
+  /**
+   * The server IP address that the request was actually sent to. Note that it may be a literal IPv6 address.
+   */
+  ip?: string;
+  /** The HTTP response headers that have been received with this response. */
+  responseHeaders?: HttpHeaders | undefined;
+  /** Standard HTTP status code returned by the server. */
+  statusCode: number;
+  /** Tracking classification if the request has been classified. */
+  urlClassification?: UrlClassification | undefined;
+  /** Indicates if this request and its content window hierarchy is third party. */
+  thirdParty: boolean;
+}