C# Programming Language
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MySqlConnectionStringBuilder turns a MySQL connection string into named properties, in both directions. It writes a valid string whatever your password holds, and it reads one back, with every default filled in. That's handy for logging settings without the password.
A connection string is a list of name=value pairs, split by ;. So a ; in your password ends the value early, and the rest looks like a strange option. Here's every case I tested, and the way to avoid thinking about it.
MySQL 9.7 allows TLS 1.3, and .NET 10 supports it, yet MySql.Data connects with TLS 1.2. It's the driver's default, on every platform. One connection string option changes that, and macOS needs one more setting.
SslMode=VerifyFull is the strongest check MySql.Data has: it verifies who signed the server's certificate, and that it's for the host you're connecting to. With PEM files, the driver also demands a client certificate and key, in one exact format. I hit each requirement in turn, so here they all are.
SslMode=Required encrypts the connection, and doesn't check who's at the other end. VerifyCA adds that check: your app only connects to a server whose certificate was signed by a CA you trust. It takes one file, and two options.
SslMode in a MySql.Data connection string decides two things: whether the connection is encrypted, and whether the driver checks who's on the other end. Required, the one most examples show, does the first and not the second. I tested each mode to see what it really does.
I published my API and started it with dotnet publish/Dewiride.Inventory.Api.dll. It ran and it answered, and it logged SQL statements that its appsettings.json turns off. The file was right there, and nothing said it wasn't being read.
My plain-text logs came out as 2026-11-06T08:00:35.102Zinfo: Program[0], with the timestamp stuck to the log level. A TimestampFormat I'd set for JSON logs had carried over to Development. Here's why, and three ways to fix it.
#:property and #:package lines configure a one-file C# program, so they have to come before anything else in it. Mine was below a using, so the build stopped with CS9297. Moving it up fixes it.
JsonSerializer.Serialize is about as ordinary as C# gets, so Reflection-based serialization has been disabled for this application was a surprise, in a one-file program with nothing else in it. File-based apps turn this off by default. There are two ways to deal with that.
