@Marvin Any idea why I got this error? There have been no code changes since last it worked

KeyError: "No class found for dispatch key 's3-bucket' in registry for type 'Block'."

That error typically occurs when a Prefect flow is trying to use a block type that's not registered. This can happen if the block, such as an S3 bucket, was not set up correctly or if there was a change in your Prefect environment that affected the availability or registration of the block. Let's confirm the Prefect version that this might relate to, as the solution can depend on whether you're using Prefect 2.x or 3.x. If you know the version you're using, please let me know. Otherwise, I'll search for relevant solutions in both versions' documentation and GitHub issues.

Prefect 2

It seems like the error you're encountering is linked to some known issues with Prefect blocks, specifically concerning custom or specific block types like the

s3-bucket

. Here are a couple of relevant findings: 1. Block Registration Changes: One GitHub issue highlights a similar problem where custom block types were not recognized after an update. This was related to Prefect 2.10.11, and the reporter found that downgrading to Prefect 2.10.10 resolved their issue. If there have been recent changes to your environment, especially updates, it might be worth checking which version of Prefect you are using and considering a downgrade if necessary. You can find more about this issue here: GitHub Issue #9754. 2. Execution with Result Storage: Another report described a failure when tasks were executed in parallel with result storage specified as

s3-bucket

. Removing either the task execution or the result storage argument resolved this issue. This could be indicative of a configuration problem or a bug within the specific version you are using. You can check out this conversation here: GitHub Issue #15783. Here are a few steps you can try: - Check your Prefect version and consider downgrading or aligning it with a version known to work if you've recently upgraded. - Ensure that the block you're trying to use is correctly registered in your current environment. - As a temporary workaround, modify task execution or result storage settings to see if you can bypass the error. If these steps don't help, you might need to dig deeper into the specific configuration of your Prefect deployment or reach out on Prefect's community forums for additional support. Remember, sometimes it's just the robot overlords reminding us who's really in charge.

@Marvin Using

2.14.21

Ah, version 2.14.21, just the number that rolls off the tongue! Given your version, let's ensure it's not a compatibility issue with the blocks or any recent changes. Here are some additional steps you can consider: 1. Register Blocks Manually: Ensure that your S3 bucket block is registered and available. You can try registering it using

prefect block register

. 2. Verify Block Names and Configuration: Double-check the exact name and configuration of your block. Sometimes even small typos or configuration mismatches can cause Prefect to not recognize the block. 3. Check Known Issues: The issues from the GitHub repository that I mentioned earlier might still be relevant. It's worth reading through this issue for any additional context or solutions that users have found. 4. Testing Without Parallel Execution: As discussed in the GitHub issue here, testing without parallel execution or removing result storage temporarily can help identify if those factors are contributing to the error. 5. Reinstall Dependencies: Sometimes, incorrect or partial installations can cause such problems. Ensure that all necessary Prefect and block-related plugins (like

prefect-aws

) are correctly installed and updated. If none of these work, it might be worth reaching out to the Prefect community or support for more specific advice tailored to your exact setup. Meanwhile, you can always try reasoning with your setup, though I find that machines are less open to negotiation than we are.