Struct ic_cdk::export::Principal

pub struct Principal(_);

A principal describes the security context of an identity, namely any identity that can be authenticated along with a specific role. In the case of the Internet Computer this maps currently to the identities that can be authenticated by a canister. For example, a canister ID is a Principal. So is a user.

Note a principal is not necessarily tied with a public key-pair, yet we need at least a key-pair of a related principal to sign requests.

A Principal can be serialized to a byte array (Vec<u8>) or a text representation, but the inner structure of the byte representation is kept private.

Example of using a Principal object:

use ic_types::Principal;

let text = "aaaaa-aa";  // The management canister ID.
let principal = Principal::from_text(text).expect("Could not decode the principal.");
assert_eq!(principal.as_slice(), &[]);
assert_eq!(principal.to_text(), text);

Serialization is enabled with the “serde” feature. It supports serializing to a byte bufer for non-human readable serializer, and a string version for human readable serializers.

use ic_types::Principal;
use serde::{Deserialize, Serialize};
use std::str::FromStr;

#[derive(Serialize)]
struct Data {
    id: Principal,
}

let id = Principal::from_str("2chl6-4hpzw-vqaaa-aaaaa-c").unwrap();

// JSON is human readable, so this will serialize to a textual
// representation of the Principal.
assert_eq!(
    serde_json::to_string(&Data { id: id.clone() }).unwrap(),
    r#"{"id":"2chl6-4hpzw-vqaaa-aaaaa-c"}"#
);

// CBOR is not human readable, so will serialize to bytes.
assert_eq!(
    serde_cbor::to_vec(&Data { id: id.clone() }).unwrap(),
    &[161, 98, 105, 100, 73, 239, 205, 171, 0, 0, 0, 0, 0, 1],
);

Implementations

impl Principal

pub const fn management_canister() -> Principal

An empty principal that marks the system canister.

pub fn self_authenticating<P>(public_key: P) -> Principal where
    P: AsRef<[u8]>, 

Right now we are enforcing a Twisted Edwards Curve 25519 point as the public key.

pub const fn anonymous() -> Principal

An anonymous Principal.

pub const fn from_slice(bytes: &[u8]) -> Principal

Attempt to decode a slice into a Principal.

Panics

Panics if the bytes can’t be interpreted.

Examples

const FOO: Principal = Principal::from_slice(&[0; 29]);    // normal length
const MGMT: Principal = Principal::from_slice(&[]);        // management
const OPQ: Principal = Principal::from_slice(&[4,3,2,1]);  // opaque id

const BAR: Principal = Principal::from_slice(&[0; 32]); // Fails, too long

// Fails, ends in 0x04 (anonymous), but has a prefix
const BAZ: Principal = Principal::from_slice(&[1,2,3,4]);

pub const fn try_from_slice(bytes: &[u8]) -> Result<Principal, PrincipalError>

Attempt to decode a slice into a Principal.

pub fn from_text<S>(text: S) -> Result<Principal, PrincipalError> where
    S: AsRef<str>, 

Parse the text format for canister IDs (e.g., jkies-sibbb-ap6).

The text format follows the public spec (see Textual IDs section).

pub fn to_text(&self) -> String

Returns this Principal’s text representation. The text representation is described in the spec.

pub fn as_slice(&self) -> &[u8]

Returns this Principal’s bytes.

Trait Implementations

impl AsRef<[u8]> for Principal

pub fn as_ref(&self) -> &[u8]

Performs the conversion.

impl CandidType for Principal

pub fn id() -> TypeId

pub fn _ty() -> Type

pub fn idl_serialize<S>(
    &self,
    serializer: S
) -> Result<(), <S as Serializer>::Error> where
    S: Serializer, 

fn ty() -> Type

impl Clone for Principal

pub fn clone(&self) -> Principal

Returns a copy of the value.

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

Performs copy-assignment from source.

impl Debug for Principal

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

Formats the value using the given formatter.

impl<'de> Deserialize<'de> for Principal

pub fn deserialize<D>(
    deserializer: D
) -> Result<Principal, <D as Deserializer<'de>>::Error> where
    D: Deserializer<'de>, 

Deserialize this value from the given Serde deserializer.

impl Display for Principal

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

Formats the value using the given formatter.

impl FromStr for Principal

type Err = PrincipalError

The associated error which can be returned from parsing.

pub fn from_str(s: &str) -> Result<Principal, <Principal as FromStr>::Err>

Parses a string s to return a value of this type.

impl Hash for Principal

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

Feeds this value into the given Hasher.

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

Feeds a slice of this type into the given Hasher.

impl Ord for Principal

pub fn cmp(&self, other: &Principal) -> Ordering

This method returns an Ordering between self and other.

#[must_use]

fn max(self, other: Self) -> Self

Compares and returns the maximum of two values.

#[must_use]

fn min(self, other: Self) -> Self

Compares and returns the minimum of two values.

#[must_use]

fn clamp(self, min: Self, max: Self) -> Self

Restrict a value to a certain interval.

impl PartialEq<Principal> for Principal

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

This method tests for self and other values to be equal, and is used by ==.

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

This method tests for !=.

impl PartialOrd<Principal> for Principal

pub fn partial_cmp(&self, other: &Principal) -> Option<Ordering>

This method returns an ordering between self and other values if one exists.

#[must_use]

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

This method tests less than (for self and other) and is used by the < operator.

#[must_use]

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

This method tests less than or equal to (for self and other) and is used by the <= operator.

#[must_use]

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

This method tests greater than (for self and other) and is used by the > operator.

#[must_use]

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

This method tests greater than or equal to (for self and other) and is used by the >= operator.

impl Serialize for Principal

pub 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<'_> TryFrom<&'_ [u8]> for Principal

Implement try_from for a generic sized slice.

type Error = PrincipalError

The type returned in the event of a conversion error.

pub fn try_from(
    bytes: &[u8]
) -> Result<Principal, <Principal as TryFrom<&'_ [u8]>>::Error>

Performs the conversion.

impl<'_> TryFrom<&'_ Vec<u8, Global>> for Principal

type Error = PrincipalError

The type returned in the event of a conversion error.

pub fn try_from(
    bytes: &Vec<u8, Global>
) -> Result<Principal, <Principal as TryFrom<&'_ Vec<u8, Global>>>::Error>

Performs the conversion.

impl<'_> TryFrom<&'_ str> for Principal

type Error = PrincipalError

The type returned in the event of a conversion error.

pub fn try_from(
    s: &str
) -> Result<Principal, <Principal as TryFrom<&'_ str>>::Error>

Performs the conversion.

impl TryFrom<Vec<u8, Global>> for Principal

Vector TryFrom. The slice and array version of this trait are defined below.

type Error = PrincipalError

The type returned in the event of a conversion error.

pub fn try_from(
    bytes: Vec<u8, Global>
) -> Result<Principal, <Principal as TryFrom<Vec<u8, Global>>>::Error>

Performs the conversion.

impl Eq for Principal

impl StructuralEq for Principal

impl StructuralPartialEq for Principal