EF Core + MySQL Empty JSON Stack Traces

[ncosentino]

Disclaimer: This might have been because I migrated posts manually, but I am not entirely sure. They seem to render completely fine in the UI from what I can see, but I am getting application exceptions flooding Azure:

An exception occurred while iterating over the results of a query for context type 'LinkDotNet.Blog.Infrastructure.Persistence.Sql.BlogDbContext'. MySqlConnector.MySqlException (0x80004005): Invalid JSON text in argument 1 to function json_table: "The document is empty." at position 0. at MySqlConnector.Core.ServerSession.ReceiveReplyAsync(IOBehavior ioBehavior, CancellationToken cancellationToken) in /_/src/MySqlConnector/Core/ServerSession.cs:line 894 at MySqlConnector.Core.ResultSet.ScanRowAsync(IOBehavior ioBehavior, Row row, CancellationToken cancellationToken) in /_/src/MySqlConnector/Core/ResultSet.cs:line 244 at MySqlConnector.Core.ResultSet.ReadAsync(IOBehavior ioBehavior, CancellationToken cancellationToken) in /_/src/MySqlConnector/Core/ResultSet.cs:line 207 at MySqlConnector.MySqlDataReader.ReadAsync(CancellationToken cancellationToken) in /_/src/MySqlConnector/MySqlDataReader.cs:line 38 at Microsoft.EntityFrameworkCore.Query.Internal.SingleQueryingEnumerable 1.AsyncEnumerator.MoveNextAsync()

As you can see, it's spamming pretty good:

I am not exactly sure what to check here -- but I think tags might be the only thing that is JSON-esque in the database columns for a blog post? I could be wrong. I cannot access my MySQL instance from this machine, but I can try to query directly and see if I find any obvious records.

Posting this simply for visibility in case it pops up anywhere else for anyone. But I may be able to close it out if I find I made an invalid record manually.

[ncosentino]

I have gone through all database records and ensured a ShortDescription is set and all Tags are set to at least have something like
["Programming"]

I'm still getting the error. For reference, I am trying to access this route:
https://devleader.ca/searchByTag/ROM
(This showed up in my cloudflare analytics so I was curious)

If I access something like this:
https://devleader.ca/searchByTag/programming

It all works as expected (no exception, and records load in the UI)

[linkdotnet]

Hey Nick,

I am pretty sure that has nothing to do with the approach of manually converting your blog posts. I suspect more MySQL or the MySQL driver for Entity Framework. I tested all the implementation details against MariaDB, which seems to have much better support for that (at least the more I dig into the topic). So I have to check what is the way forward (and don't use MariaDB for my tests :D)

PS: Also https://devleader.ca/searchByTag/programming will fail eventually if you wait.

[ncosentino]

Another quick update: If I run everything locally from visual studio and I point at my prod database, all of the mentioned routes work without issue. Of course, if I use a tag that doesn't exist it just "works" by not showing content -- but there are no page issues or anything like that.

The only differences I can think of:

• Hosting in Azure
• Cloudflare

I can't see how either of these would cause the SQL query to get botched though.

[linkdotnet]

That makes the issue even more interesting. I try to find some time the upcoming days.

[linkdotnet]

There should be a new EF 9 Version of the Pomelo LINQ Driver. I hope that fixes things.

[linkdotnet]

I am battling a different kind of beast here :D

[linkdotnet]

I don't have a solution, nor do I have a clue what is the problem. But something about the term: Dev Leader Weekly throws of the JSON Support in MySQL. Using tags like "C#" or ".NET" do work fine, but as soon as I throw in Dev Leader Weekly into the mix,
a) I get the exception you are receiving
b) If I use the generated code from EF and just executed manually against the MySQL database, it retrieves post that don't even have the tag in them.

[linkdotnet]

Probably caused by: PomeloFoundation/Pomelo.EntityFrameworkCore.MySql#1933