Reload hack to let the RSS feed reader work on ESR60

src/bg/RequestUtil.js

@@ -4,10 +4,13 @@
   let DEFAULT_CHARSET = "utf-8";
   let xmlFeedOrImage = /^(?:(?:application|text)\/(?:(?:r(?:ss|df)|atom)\+)xml(;|$))|image\//i;
   let rawXml = /^(?:application|text)\/xml;/i;
-  let brokenOnLoad = (async () => parseInt(await browser.runtime.getBrowserInfo().version) < 61);
+  let brokenOnLoad;
 
   let pendingRequests = new Map();
 
+  let reloadingTabs = new Set();
+  let tabKey = (tabId, url) => `${tabId}:${url}`;
+
   let cleanup = r => {
     pendingRequests.delete(r.requestId);
   };
@@ -15,11 +18,23 @@
     urls: ["<all_urls>"],
     types:  ["main_frame", "sub_frame", "object"]
   };
-  browser.webRequest.onCompleted.addListener(cleanup, filter);
+
+
+  browser.webRequest.onCompleted.addListener(r => {
+    cleanup(r);
+    let {tabId, url} = r;
+    let key = tabKey(tabId, url);
+    if (reloadingTabs.has(key)) {
+      debug("Reloading tab", key);
+      browser.tabs.update(tabId, {url});
+    }
+  }, filter);
   browser.webRequest.onErrorOccurred.addListener(cleanup, filter);
 
   let executeAll = async (scripts, where) => {
     let {url, tabId, frameId} = where;
+
+    let count = 0;
     for (let details of scripts.values()) {
       details = Object.assign({
         runAt: "document_start",
@@ -28,11 +43,13 @@
       }, details);
       try {
         await browser.tabs.executeScript(tabId, details);
+        count++;
         debug("Execute on start OK", url, details);
       } catch (e) {
         error(e, "Execute on start failed", url, details);
       }
     }
+    return count;
   };
 
   var RequestUtil = {
@@ -42,7 +59,8 @@
     },
 
     async executeOnStart(request, details) {
-      let {requestId, tabId, frameId, statusCode} = request;
+      let {requestId, url, tabId, frameId, statusCode} = request;
+
       if (statusCode >= 300 && statusCode < 400) return;
       let scripts = pendingRequests.get(requestId);
       let scriptKey = JSON.stringify(details);
@@ -54,35 +72,57 @@
         return;
       }
 
+      if (frameId === 0) {
+        let key = tabKey(tabId, url);
+        debug("Checking whether %s is a reloading tab...", key);
+        if (reloadingTabs.has(key)) {
+          debug("Skipping dynamic script injection for reloading feed tab", key);
+          let filter = browser.webRequest.filterResponseData(requestId);
+          filter.onstart = e => {
+            reloadingTabs.delete(key);
+            filter.write(NULL);
+            filter.disconnect();
+          }
+          return;
+        }
+      }
+
       let content = this.getContentMetaData(request);
-      debug(request.url, content.type, content.charset);
+      debug(url, content.type, content.charset);
       if (xmlFeedOrImage.test(content.type) && !/\/svg\b/i.test(content.type)) return;
-      let disconnect = !(brokenOnLoad && rawXml.test(content.type));
+      if (typeof brokenOnLoad === "undefined") {
+        brokenOnLoad = await (async () => parseInt((await browser.runtime.getBrowserInfo()).version) < 61)();
+      }
+
+      let mustCheckFeed = brokenOnLoad && frameId === 0 && rawXml.test(content.type);
+      debug("mustCheckFeed = %s, brokenOnLoad = %s", mustCheckFeed, brokenOnLoad);
       let filter = browser.webRequest.filterResponseData(requestId);
       let buffer = [];
-
       let first = true;
       let runAndFlush = async () => {
-        await executeAll(scripts, request);
-        if (buffer.length) {
+        let scriptsRan = await executeAll(scripts, request);
+        if (mustCheckFeed && !scriptsRan) {
+          debug(`Marking as "must reload"`, tabId, url);
+          reloadingTabs.add(tabKey(tabId, url));
+        }
+        if (buffer && buffer.length) {
           debug("Flushing %s buffer chunks", buffer.length);
           for (let chunk of buffer) {
             filter.write(chunk);
           }
-          if (disconnect) filter.disconnect();
+          filter.disconnect();
           buffer = null;
         }
       };
 
       if (brokenOnLoad) {
         filter.onstart = event => {
-          debug(`onstart ${request.url}`);
           filter.write(NULL);
+          debug("onstart", url);
         }
       }
 
       filter.ondata = event => {
-
         if (first) {
           runAndFlush();
           first = false;
@@ -92,11 +132,12 @@
           return;
         }
 
-        debug(`ondata ${request.url}`);
+        debug("ondata", url);
         filter.write(event.data);
-        if (disconnect) filter.disconnect();
+        filter.disconnect();
       };
 
+
     }
   }
 }