Download the markdown from the content script (#65)

* Download the markdown from the content script

There are complexities that arise from passing the content to the
background script, especially when moving to Manifest V3. Avoid this by
just triggering the download directly from the content script.

* Simplify the message handler

Author: kfarnung

src/background_scripts/background.js

@@ -5,24 +5,8 @@ import {
   tabs as _tabs,
 } from "webextension-polyfill";
 
-function saveAs(text) {
-  const blob = new Blob([text], { type: "text/markdown;charset=utf-8" });
-
-  return downloads.download({
-    url: URL.createObjectURL(blob),
-    filename: "README.md",
-    saveAs: true,
-  });
-}
-
 runtime.onMessage.addListener((data, sender) => {
   switch (data.action) {
-    case "saveAs":
-      saveAs(data.text).catch((err) => {
-        console.error("Failed to save content", err);
-      });
-      break;
-
     case "showPageAction":
       pageAction.show(sender.tab.id);
       break;

src/content_scripts/to-markdown.js

@@ -79,6 +79,16 @@ function expandHrefs(article) {
   }
 }
 
+function downloadBlob(blob) {
+  const downloadLink = document.createElement('a');
+  downloadLink.href = URL.createObjectURL(blob);
+  downloadLink.download = 'README.md';
+  document.body.appendChild(downloadLink);
+  downloadLink.click();
+  document.body.removeChild(downloadLink);
+  URL.revokeObjectURL(downloadLink.href);
+}
+
 function capturePage() {
   const newDoc = document.createDocumentFragment();
   const titleElement = document.createElement("h1");
@@ -115,17 +125,13 @@ function capturePage() {
     newDoc.appendChild(article);
   }
 
-  return generateMarkdown(newDoc);
+  const text = generateMarkdown(newDoc);
+  const blob = new Blob([text], { type: "text/markdown;charset=utf-8" });
+  downloadBlob(blob);
 }
 
 runtime.onMessage.addListener((data) => {
   if (data.action === "capturePage") {
-    const markdown = capturePage();
-    return runtime
-      .sendMessage({
-        action: "saveAs",
-        text: markdown,
-      })
-      .catch((err) => console.error("Failed to send 'saveAs' message", err));
+    capturePage();
   }
 });

webpack.config.js

@@ -13,4 +13,7 @@ module.exports = {
     path: path.resolve(__dirname, "addon"),
     filename: "[name]/index.js",
   },
+  optimization: {
+    minimize: false,
+  },
 };