Fix: SQL Lab Copy Link To Clipboard Bug

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Fix: SQL Lab Copy Link to Clipboard Bug

Hey everyone! We're diving into a pretty annoying bug in Superset's SQL Lab that's been causing headaches for users trying to share their saved queries. Basically, the app tries to copy the query link to your clipboard when you open a saved query, but it's so eager to redirect you to SQL Lab that the copy operation often fails. No bueno!

Current Behavior

So, here's the deal. When you open a saved query in SQL Lab, Superset attempts to copy the link to your clipboard. But, because the clipboard API works asynchronously (meaning it takes a little time), and the page immediately redirects to SQL Lab, the copy often doesn't complete. You're left with nothing in your clipboard, and no clue that anything went wrong. It's like a magic trick gone wrong – poof, nothing!

Here’s how you can reproduce the issue:

  1. Go to your list of Saved Queries in Superset.
  2. Click on any saved query to open it in SQL Lab (doesn't matter if it’s the same window or a new one).
  3. Try pasting the clipboard contents somewhere (like a text editor).
  4. Surprise! Either you'll find old content, or nothing at all. The copy never happened, and the app didn’t even bother to tell you.

This is super frustrating because it makes sharing queries a pain. Imagine trying to collaborate with a colleague, and you can't even reliably send them a link to the query you're working on. Not cool.

Expected Behavior

Okay, so what should happen? When you open a saved query in SQL Lab, the application should first copy the query link to the clipboard. It should then patiently wait for that operation to finish before doing anything else. And, most importantly, it should give you some feedback! A little toast notification saying "Link Copied!" would be awesome.

Only after the clipboard operation is done (whether it succeeds or fails) should the app navigate you to SQL Lab. This ensures that the link is actually in your clipboard when you need it.

In a nutshell, here's what we expect:

  • The link to the saved query is successfully copied to the clipboard before any navigation happens.
  • A sweet success toast notification pops up, saying "Link Copied!" when the copy works.
  • Navigation to SQL Lab (same or new window) only occurs after the clipboard operation is complete.
  • Everything works smoothly whether you open the query in the same window or a new one.

Steps To Test

Alright, team, here’s how we can make sure this fix does its job. Follow these steps to verify the behavior:

  1. Head over to the Saved Queries list page in Superset.
  2. Click on any saved query to open it in SQL Lab.
  3. Keep your eyes peeled for a toast notification that says, “Link Copied!” If you see it, that’s a good sign!
  4. Open up your favorite text editor or another application.
  5. Paste from the clipboard (Ctrl+V or Cmd+V).
  6. Double-check that the pasted content is a valid URL. It should look something like this: {origin}/sqllab?savedQueryId={id}. The {origin} part will be your Superset base URL, and the {id} will be the ID of your saved query.
  7. If you're feeling extra thorough, test opening a query in a new window (if your setup allows it) and make sure the same clipboard behavior works there too.
  8. For the truly adventurous, try testing in a browser or environment where clipboard access is restricted. In this case, you should see an error toast notification instead of the success one. This confirms that the app is handling errors gracefully.

By following these steps, we can ensure that the fix behaves as expected and provides a much better user experience.

Why This Matters

This issue might seem small, but it touches on a few important principles:

  • User Feedback: Users need to know what's going on. A simple toast notification can make a huge difference in user confidence.
  • Asynchronous Operations: Dealing with asynchronous operations correctly is crucial for modern web apps. We can't just assume things happen instantly.
  • Reliability: Copying a link to the clipboard should be a reliable, everyday task. Users shouldn't have to guess whether it worked or not.

By addressing this bug, we're not just fixing a minor inconvenience; we're improving the overall quality and usability of Superset.

Diving Deeper: The Technical Nuances

For those of you who like to get into the weeds, let's talk about some of the technical challenges involved in fixing this bug.

The Clipboard API

The Clipboard API in modern browsers is a powerful tool, but it's not without its quirks. As mentioned earlier, it operates asynchronously. This means that when you call navigator.clipboard.writeText(), the browser doesn't immediately copy the text to the clipboard. Instead, it kicks off the copy operation in the background and returns a Promise. The Promise resolves when the copy is successful and rejects if there's an error.

The key here is to wait for the Promise to resolve or reject before proceeding. If we don't wait, the browser might not have enough time to complete the copy operation before the page unloads, leading to the failure we've been discussing.

The Redirect Problem

The immediate redirect to SQL Lab is the main culprit here. When the user clicks on a saved query, the application initiates the copy operation and immediately starts navigating to the SQL Lab page. This is a race condition: the copy operation might win, or the redirect might win. In many cases, the redirect wins, and the copy fails.

The Solution: Patience and Feedback

The solution involves two key elements:

  1. Patience: We need to delay the redirect until the copy operation is complete. This means awaiting the Promise returned by navigator.clipboard.writeText().
  2. Feedback: We need to provide the user with feedback about the status of the copy operation. This can be done using a toast notification library. When the Promise resolves, we show a success toast. When the Promise rejects, we show an error toast.

Potential Challenges

Even with these principles in mind, there are still potential challenges to overcome:

  • Browser Compatibility: The Clipboard API isn't supported in all browsers. We need to handle cases where the API is not available gracefully.
  • Permissions: In some browsers or environments, users might need to grant permission for the application to access the clipboard. We need to handle cases where permission is denied.
  • Error Handling: The Clipboard API can throw errors for various reasons. We need to catch these errors and provide informative error messages to the user.

By carefully considering these challenges, we can create a robust and reliable solution that improves the user experience in Superset.

Wrapping Up

So, that’s the scoop on this SQL Lab clipboard bug. By ensuring the link is copied before navigation and providing feedback, we're making Superset a little more user-friendly. Thanks for helping us squash this bug and make Superset even better!

Remember to follow the submission guidelines (record your screen with https://cap.so/ and export as an mp4) and consult the pull request guide (https://hackmd.io/@timothy1ee/Hky8kV3hlx) when submitting your fix. Happy coding!