Struct HeaderMap

pub struct HeaderMap { /* private fields */ }

A struct for handling NATS headers. Has a similar API to http::header, but properly serializes and deserializes according to NATS requirements.

Examples

let client = async_nats::connect("demo.nats.io").await?;
let mut headers = async_nats::HeaderMap::new();
headers.insert("Key", "Value");
client
    .publish_with_headers("subject", headers, "payload".into())
    .await?;

Implementations

impl HeaderMap

pub fn iter(&self) -> Iter<'_, HeaderName, Vec<HeaderValue>>

impl HeaderMap

pub fn new() -> HeaderMap

Create an empty HeaderMap.

Examples

let map = HeaderMap::new();

assert!(map.is_empty());

pub fn is_empty(&self) -> bool

Returns true if the map contains no elements.

Examples

let mut map = HeaderMap::new();

assert!(map.is_empty());

map.insert(NATS_SUBJECT, "FOO.BAR");

assert!(!map.is_empty());

pub fn len(&self) -> usize

impl HeaderMap

pub fn insert<K, V>(&mut self, name: K, value: V)

where K: IntoHeaderName, V: IntoHeaderValue,

Inserts a new value to a HeaderMap.

Examples

use async_nats::HeaderMap;

let mut headers = HeaderMap::new();
headers.insert("Key", "Value");

pub fn append<K, V>(&mut self, name: K, value: V)

where K: IntoHeaderName, V: IntoHeaderValue,

Appends a new value to the list of values to a given key. If the key did not exist, it will be inserted with provided value.

Examples

use async_nats::HeaderMap;

let mut headers = HeaderMap::new();
headers.append("Key", "Value");
headers.append("Key", "Another");

pub fn get<K>(&self, key: K) -> Option<&HeaderValue>

where K: IntoHeaderName,

Gets a value for a given key. If key is not found, Option::None is returned.

Examples

let mut headers = HeaderMap::new();
headers.append("Key", "Value");
let values = headers.get("Key").unwrap();

pub fn get_last<K>(&self, key: K) -> Option<&HeaderValue>

where K: IntoHeaderName,

Gets a last value for a given key. If key is not found, Option::None is returned.

Examples

let mut headers = HeaderMap::new();
headers.append("Key", "Value");
let values = headers.get_last("Key").unwrap();

pub fn get_all<K>(&self, key: K) -> GetAll<'_, HeaderValue>

where K: IntoHeaderName,

Gets an iterator to the values for a given key.

Examples

let mut headers = HeaderMap::new();
headers.append("Key", "Value1");
headers.append("Key", "Value2");
let mut values = headers.get_all("Key");
let value1 = values.next();
let value2 = values.next();

Trait Implementations

impl Clone for HeaderMap

fn clone(&self) -> HeaderMap

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for HeaderMap

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

Formats the value using the given formatter.

impl Default for HeaderMap

fn default() -> HeaderMap

Returns the “default value” for a type.

impl<'de> Deserialize<'de> for HeaderMap

fn deserialize<__D>( __deserializer: __D, ) -> Result<HeaderMap, <__D as Deserializer<'de>>::Error>

where __D: Deserializer<'de>,

Deserialize this value from the given Serde deserializer.

impl FromIterator<(HeaderName, HeaderValue)> for HeaderMap

fn from_iter<T>(iter: T) -> HeaderMap

where T: IntoIterator<Item = (HeaderName, HeaderValue)>,

Creates a value from an iterator.

impl PartialEq for HeaderMap

fn eq(&self, other: &HeaderMap) -> 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 Serialize for HeaderMap

fn serialize<__S>( &self, __serializer: __S, ) -> Result<<__S as Serializer>::Ok, <__S as Serializer>::Error>

where __S: Serializer,

Serialize this value into the given Serde serializer.

impl Eq for HeaderMap

impl StructuralPartialEq for HeaderMap