#transport API reference

The shared connection-transport security mode, used by every network-client module that opens a socket (smtp, pop, imap, redis, amqp, mqtt). One closed enum instead of a stringly-typed security field per module, so a value is typed and a typo is a compile-time error, not a silent plaintext downgrade.

Security.None is plaintext, Security.Tls is implicit TLS on connect, and Security.Starttls is an in-band upgrade after connecting (SMTP STARTTLS, POP3 STLS, IMAP STARTTLS). A module that has no in-band upgrade (redis, amqp, mqtt) rejects Security.Starttls with a clear error rather than treating it as anything else.

Build a connection option with a variant directly: smtp.Options{security: transport.Security.Starttls, ...} - which needs import "transport.j" as transport; alongside the client module.

Import with import "transport.j" as transport;. See the transport guide for prose and examples.

#Functions

#transport.checkReceiveSize(n as int, what as string)

Reject a received / declared size that is negative or exceeds MAX_RECEIVED_BYTES, raising a catchable Error{kind: "transport"} that names what. Call it on a peer-declared body / literal size before reading it, and on an accumulating buffer's length inside a read loop, so an endless or oversized stream fails typed instead of exhausting memory.

Parameters

• n {int} - the size to check (a declared size, or a running buffer length)
• what {string} - a short label for the message (e.g. "amqp message body")

#transport.encrypted(s as Security)

Whether a security mode encrypts the connection (Tls or Starttls). None is the only unencrypted mode. Handy for a "refuse to send credentials over plaintext" guard.

Parameters

• s {Security} - the security mode

Returns {bool} - true if the connection is (or becomes) encrypted

#Enums

#transport.Security

A connection's transport security mode. - None - plaintext (no encryption). - Tls - implicit TLS negotiated on connect (SMTPS / POP3S / IMAPS / rediss / ...). - Starttls - connect in plaintext, then upgrade in-band (SMTP STARTTLS, POP3 STLS, IMAP STARTTLS). Only the protocols with an upgrade command accept it.

#Constants