Struct ServerCapabilities 

#[non_exhaustive]
pub struct ServerCapabilities { /* private fields */ }

Server capabilities parsed from EHLO response (RFC 5321 Section 4.1.1.1).

Implementations

impl ServerCapabilities

pub fn greeting_name(&self) -> &str

Returns the server’s greeting name from the EHLO response.

pub fn extensions(&self) -> &[SmtpExtension]

Returns the server’s advertised extensions.

pub fn supports_auth(&self, mechanism: &AuthMechanism) -> bool

Check if the server supports a given auth mechanism.

RFC 4954 Section 3 / RFC 4422 Section 3.1: SASL mechanism names are case-insensitive, so this method performs case-insensitive matching for AuthMechanism::Other variants.

pub fn supports_auth_extension(&self) -> bool

Check if the server advertises the AUTH extension at all.

RFC 4954 Section 3: the EHLO AUTH keyword advertises support for the AUTH command and the MAIL FROM AUTH parameter.

pub fn supports_starttls(&self) -> bool

Check if the server advertises STARTTLS.

pub fn supports_chunking(&self) -> bool

Check if the server supports CHUNKING (BDAT).

pub fn supports_size(&self) -> bool

Check if the server supports the SIZE extension (RFC 1870).

Returns true when the server advertises SIZE, regardless of whether a numeric limit was included. Use Self::size_limit to retrieve the limit value.

pub fn size_limit(&self) -> Option<u64>

Get the SIZE limit, if advertised.

pub fn supports_8bitmime(&self) -> bool

Check if the server supports 8BITMIME (RFC 1652).

pub fn supports_binarymime(&self) -> bool

Check if the server supports BINARYMIME (RFC 3030).

pub fn supports_8bit_or_binary(&self) -> bool

Check if the server supports either 8BITMIME (RFC 1652) or BINARYMIME (RFC 3030).

RFC 1652 Section 1 / RFC 3030 Section 2: when neither extension is advertised, the SMTP client is limited to 7-bit US-ASCII content. Either extension satisfies the requirement for non-7-bit BODY parameters.

pub fn supports_pipelining(&self) -> bool

Check if the server supports PIPELINING (RFC 1854).

pub fn supports_smtputf8(&self) -> bool

Check if the server supports SMTPUTF8 (RFC 6531).

pub fn supports_sasl_ir(&self) -> bool

Check whether the server advertised the legacy SASL-IR keyword.

RFC 4954 Section 4 already allows SMTP AUTH initial responses without a separate capability. This accessor is retained only so callers can inspect the EHLO response as advertised.

pub fn supports_dsn(&self) -> bool

Check if the server supports DSN (RFC 3461).

When advertised, the server accepts Delivery Status Notification parameters on MAIL FROM (RET, ENVID) and RCPT TO (NOTIFY, ORCPT) per RFC 3461 Sections 4.1–4.4.

pub fn supports_requiretls(&self) -> bool

Check if the server supports REQUIRETLS (RFC 8689).

When advertised, the client may include the REQUIRETLS parameter on MAIL FROM to enforce TLS on every hop (RFC 8689 Sections 2–4).

pub fn supports_future_release(&self) -> bool

Check if the server supports FUTURERELEASE (RFC 4865).

pub fn future_release_max_interval(&self) -> Option<u64>

Get the server-advertised FUTURERELEASE maximum hold interval in seconds, if any (RFC 4865 Section 4).

pub fn future_release_max_datetime(&self) -> Option<&str>

Get the server-advertised FUTURERELEASE maximum hold-until datetime string, if any (RFC 4865 Section 4).

pub fn supports_deliver_by(&self) -> bool

Check if the server supports DELIVERBY (RFC 2852).

pub fn deliver_by_min(&self) -> Option<u64>

Get the server-advertised DELIVERBY minimum time in seconds, if any (RFC 2852 Section 2).

pub fn supports_mt_priority(&self) -> bool

Check if the server supports MT-PRIORITY (RFC 6758).

pub fn supports_vrfy(&self) -> bool

Check if the server supports VRFY (RFC 5321 Section 4.1.1.6).

pub fn supports_expn(&self) -> bool

Check if the server supports EXPN (RFC 5321 Section 4.1.1.7).

pub fn supports_enhanced_status_codes(&self) -> bool

Check if the server supports Enhanced Status Codes (RFC 2034).

When advertised, the server includes enhanced status codes (class.subject.detail) in its response text per RFC 2034 Section 3.

Trait Implementations

impl Clone for ServerCapabilities

fn clone(&self) -> ServerCapabilities

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for ServerCapabilities

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Default for ServerCapabilities

fn default() -> ServerCapabilities

Returns the “default value” for a type.

impl Hash for ServerCapabilities

fn hash<__H: Hasher>(&self, state: &mut __H)

Feeds this value into the given Hasher.

fn hash_slice<H>(data: &[Self], state: &mut H)

where H: Hasher, Self: Sized,

Feeds a slice of this type into the given Hasher.

impl PartialEq for ServerCapabilities

fn eq(&self, other: &ServerCapabilities) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl Eq for ServerCapabilities

impl StructuralPartialEq for ServerCapabilities