Struct Encoding

Source

pub struct Encoding(/* private fields */);

Expand description

§Encoding information

The Sample or ReplyError may contain the optional encoding value, which indicates how the payload should be interpreted by the application.

The encoding is represented as a string in MIME-like format: type/subtype[;schema].

To optimize network usage, Zenoh internally maps some predefined encoding strings to an integer identifier. These encodings are provided as associated constants of the Encoding struct, e.g. Encoding::ZENOH_BYTES, Encoding::APPLICATION_JSON, etc. This internal mapping is not exposed to the application layer and, from the API point of view, the encoding is always represented as a string. But it’s useful to know that some encodings are much more efficient than others, especially considering that the encoding value is sent with each message.

Please note that the Zenoh protocol does not impose any encoding value, nor does it operate on it. It can be seen as optional metadata that is carried over by Zenoh in such a way that the application may perform different operations depending on the encoding value.

§Examples

§String operations

Create an Encoding from a string and vice versa.

use zenoh::bytes::Encoding;

let encoding: Encoding = "text/plain".into();
let text: String = encoding.clone().into();
assert_eq!("text/plain", &text);

§Constants and cow operations

Since some encoding values are internally optimized by Zenoh, it’s generally more efficient to use the defined constants and Cow conversion to obtain its string representation.

use zenoh::bytes::Encoding;
use std::borrow::Cow;

// This allocates
assert_eq!("text/plain", &String::from(Encoding::TEXT_PLAIN));
// This does NOT allocate
assert_eq!("text/plain", &Cow::from(Encoding::TEXT_PLAIN));

§Schema

Additionally, a schema can be associated with the encoding. The convention is to use the ; separator if an encoding is created from a string. Alternatively, with_schema() can be used to add a schema to one of the associated constants.

use zenoh::bytes::Encoding;

let encoding1 = Encoding::from("text/plain;utf-8");
let encoding2 = Encoding::TEXT_PLAIN.with_schema("utf-8");
assert_eq!(encoding1, encoding2);
assert_eq!("text/plain;utf-8", &encoding1.to_string());
assert_eq!("text/plain;utf-8", &encoding2.to_string());

Struct Encoding Copy item path

§Encoding information

§Examples

§String operations

§Constants and cow operations

§Schema

Implementations§

impl Encoding

pub const ZENOH_BYTES: Encoding

pub const ZENOH_STRING: Encoding

pub const ZENOH_SERIALIZED: Encoding

pub const APPLICATION_OCTET_STREAM: Encoding

pub const TEXT_PLAIN: Encoding

pub const APPLICATION_JSON: Encoding

pub const TEXT_JSON: Encoding

pub const APPLICATION_CDR: Encoding

pub const APPLICATION_CBOR: Encoding

pub const APPLICATION_YAML: Encoding

pub const TEXT_YAML: Encoding

pub const TEXT_JSON5: Encoding

pub const APPLICATION_PYTHON_SERIALIZED_OBJECT: Encoding

pub const APPLICATION_PROTOBUF: Encoding

pub const APPLICATION_JAVA_SERIALIZED_OBJECT: Encoding

pub const APPLICATION_OPENMETRICS_TEXT: Encoding

pub const IMAGE_PNG: Encoding

pub const IMAGE_JPEG: Encoding

pub const IMAGE_GIF: Encoding

pub const IMAGE_BMP: Encoding

pub const IMAGE_WEBP: Encoding

pub const APPLICATION_XML: Encoding

pub const APPLICATION_X_WWW_FORM_URLENCODED: Encoding

pub const TEXT_HTML: Encoding

pub const TEXT_XML: Encoding

pub const TEXT_CSS: Encoding

pub const TEXT_JAVASCRIPT: Encoding

pub const TEXT_MARKDOWN: Encoding

pub const TEXT_CSV: Encoding

pub const APPLICATION_SQL: Encoding

pub const APPLICATION_COAP_PAYLOAD: Encoding

pub const APPLICATION_JSON_PATCH_JSON: Encoding

pub const APPLICATION_JSON_SEQ: Encoding

pub const APPLICATION_JSONPATH: Encoding

pub const APPLICATION_JWT: Encoding

pub const APPLICATION_MP4: Encoding

pub const APPLICATION_SOAP_XML: Encoding

pub const APPLICATION_YANG: Encoding

pub const AUDIO_AAC: Encoding

pub const AUDIO_FLAC: Encoding

pub const AUDIO_MP4: Encoding

pub const AUDIO_OGG: Encoding

pub const AUDIO_VORBIS: Encoding

pub const VIDEO_H261: Encoding

pub const VIDEO_H263: Encoding

pub const VIDEO_H264: Encoding

pub const VIDEO_H265: Encoding

pub const VIDEO_H266: Encoding

pub const VIDEO_MP4: Encoding

pub const VIDEO_OGG: Encoding

pub const VIDEO_RAW: Encoding

pub const VIDEO_VP8: Encoding

pub const VIDEO_VP9: Encoding

pub const fn default() -> Self

pub fn with_schema<S>(self, s: S) -> Selfwhere S: Into<String>,

Trait Implementations§

impl Clone for Encoding

fn clone(&self) -> Encoding

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

impl Debug for Encoding

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

impl Default for Encoding

fn default() -> Self

impl Display for Encoding

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

impl From<&Encoding> for Cow<'static, str>

fn from(encoding: &Encoding) -> Self

impl From<&str> for Encoding

fn from(t: &str) -> Self

impl From<Encoding> for Cow<'static, str>

fn from(encoding: Encoding) -> Self

impl From<Encoding> for Encoding

Struct Encoding

pub fn with_schema<S>(self, s: S) -> Self
where S: Into<String>,

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

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

fn ref_as<T>(&self) -> <Source as IGuardRef<T>>::Guard<'_>
where Source: IGuardRef<T>, T: ?Sized,

fn mut_as<T>(&mut self) -> <Source as IGuardMut<T>>::GuardMut<'_>
where Source: IGuardMut<T>, T: ?Sized,

impl<T> Any for T
where T: 'static + ?Sized,

impl<'a, T, E> AsTaggedExplicit<'a, E> for T
where T: 'a,

impl<'a, T, E> AsTaggedImplicit<'a, E> for T
where T: 'a,

impl<T> Borrow<T> for T
where T: ?Sized,

impl<T> BorrowMut<T> for T
where T: ?Sized,

impl<T> CloneToUninit for T
where T: Clone,

impl<T> DynClone for T
where T: Clone,

impl<Q, K> Equivalent<K> for Q
where Q: Eq + ?Sized, K: Borrow<Q> + ?Sized,

impl<Q, K> Equivalent<K> for Q
where Q: Eq + ?Sized, K: Borrow<Q> + ?Sized,

impl<Q, K> Equivalent<K> for Q
where Q: Eq + ?Sized, K: Borrow<Q> + ?Sized,

impl<T, As> IGuardMut<As> for T
where T: Into<As>, As: Into<T>,

impl<T, As> IGuardRef<As> for T
where T: Into<As>, As: Into<T>,