Error Handling

Real Redis is strict about argument counts and case-insensitive about command names. Let's match that.

Case Insensitivity

Redis treats PING, ping, Ping, and pInG identically. Convert the command name to uppercase before matching.

Argument Validation

Each command has an expected argument count:

• PING → 0 or 1 args
• ECHO → exactly 1 arg

Wrong argument count returns: -ERR wrong number of arguments for '<cmd>' command\r\n

Empty Lines

Skip blank lines silently — don't return an error.

Defensive Programming

From this point forward, every command you implement should validate its arguments. This prevents crashes and matches Redis's behavior.