Troubleshoot: Self-Hosted PLC Authentication With GetProfile

by Rajiv Sharma 61 views

Hey everyone,

I'm encountering a tricky issue and hoping someone might have some insights. I'm running a self-hosted PLC (Personal Lexicon Collection) directory and PDS (Personal Data Server), and I'm running into authentication problems specifically when using the app.bsky.actor.getProfile lexicon. Other lexicons, including some bsky ones like get preferences and all atproto lexicons, seem to be working just fine. It's a head-scratcher!

The error I'm seeing seems to originate from the verify JWT method in this file: https://github.com/bluesky-social/atproto/blob/main/packages/bsky/src/auth-verifier.ts. This suggests the issue lies within the JWT (JSON Web Token) verification process when handling the app.bsky.actor.getProfile request.

Diving Deeper into the Problem

The Specific Error Context

The error arises specifically when I try to use the app.bsky.actor.getProfile lexicon within my Bluesky setup. This particular lexicon is crucial for fetching user profile information, making it a core component of the application. The fact that other bsky lexicons, such as get preferences, work without issues, narrows the problem down to how app.bsky.actor.getProfile is handled in relation to the self-hosted PLC directory.

JWT Verification Issues

The error message points to the verify JWT method in the auth-verifier.ts file within the atproto repository. JWTs are used to verify the identity of the user making the request, ensuring that the server knows who is asking for what. When this verification fails, it means there's a mismatch or issue in the token's signature, claims, or overall structure. In this case, it seems the self-hosted PLC directory might be interacting differently with the JWT when processing app.bsky.actor.getProfile requests compared to other requests.

Self-Hosted PLC Directory Functionality

My custom PLC directory appears to be functioning correctly in general. The PDS can successfully write to and read from it, indicating that the basic connectivity and data storage aspects are working. This makes the issue even more perplexing, as it suggests the problem isn't a fundamental misconfiguration of the PLC directory but rather a specific interaction issue with the getProfile method. The fact that writes and reads are successful indicates that the PLC directory itself is operational and accessible, making the authentication failure with getProfile all the more intriguing.

Potential Hardcoding Issues

One thought I had was whether plc.directory might be hardcoded somewhere in the codebase, causing the system to bypass my self-hosted setup for this specific lexicon. It’s possible that certain parts of the application are still pointing to the default plc.directory, which would explain why the authentication fails when using a custom PLC. However, this seems less likely since other bsky lexicons are working, suggesting that the system is generally configured to use the custom PLC. Still, it's a possibility worth investigating.

Handling of Different Lexicons

It's interesting that some bsky lexicons (like get preferences) work while app.bsky.actor.getProfile doesn't. This could indicate that different lexicons have different authentication requirements or are processed through different code paths. The fact that atproto lexicons all succeed further complicates the picture, suggesting that the issue is specific to how bsky lexicons, and particularly app.bsky.actor.getProfile, are handled within the system.

Expected Failures and Other Errors

I'm also seeing some other failures, but these seem to be related to hardcoded DIDs (Decentralized Identifiers) that don't exist in my setup. This is probably expected behavior, as these DIDs would likely be pointing to resources or users in a different environment. These failures don't seem to be directly related to the app.bsky.actor.getProfile issue, but it’s important to keep them in mind while troubleshooting.

Possible Causes and Troubleshooting Steps

1. JWT Claim Differences

Could the app.bsky.actor.getProfile lexicon be expecting specific claims in the JWT that are not present when using a self-hosted PLC? This is a key area to investigate. JWT claims are pieces of information asserted about a user, and if getProfile requires specific claims that are not being provided by your self-hosted PLC, the verification will fail. You should inspect the JWTs being generated for getProfile requests and compare them to those used for successful requests to see if there are any discrepancies.

To address this:

  • Inspect JWT Payloads: Use a JWT decoding tool (like jwt.io) to examine the payloads of the JWTs being used in both successful and failed requests. Look for differences in the claims included.
  • Verify Claim Requirements: Check the app.bsky.actor.getProfile lexicon definition and related code to see if there are any explicitly required claims.
  • Customize JWT Generation: If necessary, adjust your self-hosted PLC's JWT generation process to include the required claims.

2. PLC Directory Configuration

Double-check that your self-hosted PLC directory is correctly configured and reachable. While the PDS can write to and read from it, there might be subtle configuration issues affecting JWT verification. It's essential to ensure that the PLC directory is correctly configured to handle authentication requests, and that all necessary DNS records and server settings are in place.

To address this:

  • DNS Settings: Ensure that your DNS settings correctly point to your self-hosted PLC directory.
  • Server Configuration: Verify that your server is properly configured to handle requests to the PLC directory, including SSL/TLS settings.
  • PLC Directory Logs: Check the logs of your PLC directory for any error messages or warnings that might indicate a problem.

3. Hardcoded plc.directory Instances

Despite my initial thought that this is less likely, it's still worth thoroughly checking the codebase for any hardcoded references to plc.directory. A simple search within the codebase can reveal if there are any instances where the default PLC directory is being used instead of the configured one. Even if the primary configuration points to your self-hosted PLC, there might be fallback mechanisms or specific functions that still rely on the default directory.

To address this:

  • Codebase Search: Use a code search tool (like grep or the search function in your IDE) to look for any instances of plc.directory in the codebase.
  • Configuration Overrides: Ensure that your application is correctly using environment variables or configuration files to override any default PLC directory settings.

4. Lexicon-Specific Authentication Logic

Investigate whether the app.bsky.actor.getProfile lexicon has any unique authentication logic or middleware that might be causing the issue. It's possible that this specific lexicon is processed differently than others, with additional steps or checks that are failing in the context of your self-hosted PLC. This could involve examining the request handling pipeline for getProfile and comparing it to that of other working lexicons.

To address this:

  • Request Handling Pipeline: Trace the request handling pipeline for app.bsky.actor.getProfile to identify any unique steps or middleware.
  • Authentication Checks: Look for any specific authentication checks or logic that might be applied only to this lexicon.
  • Code Comparison: Compare the code paths for getProfile and other working lexicons to identify any differences that could be causing the issue.

5. Dependency Version Mismatches

Ensure that all your dependencies are up-to-date and that there are no version mismatches between the components of your Bluesky setup. Dependency conflicts can sometimes lead to unexpected behavior, especially in complex systems like this. Check the versions of your libraries and frameworks to ensure they are compatible with each other and with the atproto library.

To address this:

  • Dependency Audit: Use a dependency management tool (like npm audit or yarn audit) to check for any known vulnerabilities or version conflicts.
  • Version Alignment: Ensure that all relevant libraries and frameworks are at compatible versions.
  • Update Dependencies: If necessary, update your dependencies to the latest versions, while being mindful of potential breaking changes.

Next Steps

I'm planning to start by inspecting the JWT payloads to see if there are any missing or incorrect claims. I'll also double-check my PLC directory configuration and search the codebase for any hardcoded plc.directory references. If anyone has encountered a similar issue or has any other suggestions, I'm all ears! I’ll keep this thread updated as I make progress.

Thanks in advance for any help you can offer, guys! This is a really interesting problem, and I'm excited to get to the bottom of it. Hopefully, by sharing my troubleshooting steps and findings, we can help others who might encounter similar issues in the future. Let's work together to make self-hosting Bluesky as smooth as possible!

I hope this comprehensive breakdown of the problem and potential solutions helps others facing similar challenges. Remember, the key to effective troubleshooting is methodical investigation and clear communication. Let’s keep this conversation going and support each other in building a robust and decentralized social network!