how do I access host filesystem within devtool?

[Shi Yan]

I want to build an IDE to facilitate scraper development. 

The IDE will be a devTool. But I need to be able to open files/folders and write to them. The "Sources" tab in devtool can do that. How do I do the same in my devtool extension?

[guest271314]

You can utilize Native File System to open files and folders and read or write the contents.

[bill...@gmail.com]

I tried this https://developer.chrome.com/apps/fileSystem, totally not working.

await window.chooseFileSystemEntries(options) doesn't work either

[bill...@gmail.com]

Uncaught (in promise) DOMException: Failed to execute 'chooseFileSystemEntries' on 'Window': Cross origin sub frames aren't allowed to show a file picker.

    at HTMLButtonElement.open (chrome-extension://nadpfibhpdomkeafkmcoapimjohefkob/script.js:55:17)

[guest271314]

User action is required, which can be achieved using click or other mouse event, then, in main window

    const dir = await showDirectoryPicker();

    // set mode to readwrite for app/data directory

    const status = await dir.requestPermission({ mode: 'readwrite' });

    let fileHandle = await dir.getFileHandle('file', {

                                  create: true

                               });

To communicate with Chromium extension or Chromium app you can use messaging. This code https://github.com/guest271314/captureSystemAudio/tree/master/native_messaging/file_stream uses Native Messaging and Native File System, messages are sent to and from main window to Chromium app, after setting permissions for location.origin by reading and re-writing manifest.json https://github.com/guest271314/captureSystemAudio/blob/master/native_messaging/file_stream/app/set_externally_connectable.js to dynamically set externally_connectable permissions for the site.