pub struct Principal { /* private fields */ }
Expand description

Generic ID on Internet Computer.

Principals are generic identifiers for canisters, users and possibly other concepts in the future. As far as most uses of the IC are concerned they are opaque binary blobs with a length between 0 and 29 bytes, and there is intentionally no mechanism to tell canister ids and user ids apart.

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:

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(), &[] as &[u8]);
assert_eq!(principal.to_text(), text);

Similarly, serialization using serde has two versions: serilizing to a byte bufer for non-human readable serializer, and a string version for human readable serializers.

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

Construct a Principal of the IC management canister

Construct a self-authenticating ID from public key

Construct an anonymous ID.

Construct a Principal from a slice of bytes.

Panics

Panics if the slice is longer than 29 bytes.

Construct a Principal from a slice of bytes.

Parse a Principal from text representation.

Convert Principal to text representation.

Return the Principal’s underlying slice of bytes.

Trait Implementations

Converts this type into a shared reference of the (usually inferred) input type.
Returns a copy of the value. Read more
Performs copy-assignment from source. Read more
Formats the value using the given formatter. Read more
Deserialize this value from the given Serde deserializer. Read more
Formats the value using the given formatter. Read more
The associated error which can be returned from parsing.
Parses a string s to return a value of this type. Read more
Feeds this value into the given Hasher. Read more
Feeds a slice of this type into the given Hasher. Read more
This method returns an Ordering between self and other. Read more
Compares and returns the maximum of two values. Read more
Compares and returns the minimum of two values. Read more
Restrict a value to a certain interval. Read more
This method tests for self and other values to be equal, and is used by ==. Read more
This method tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason. Read more
This method returns an ordering between self and other values if one exists. Read more
This method tests less than (for self and other) and is used by the < operator. Read more
This method tests less than or equal to (for self and other) and is used by the <= operator. Read more
This method tests greater than (for self and other) and is used by the > operator. Read more
This method tests greater than or equal to (for self and other) and is used by the >= operator. Read more
Serialize this value into the given Serde serializer. Read more
The type returned in the event of a conversion error.
Performs the conversion.
The type returned in the event of a conversion error.
Performs the conversion.
The type returned in the event of a conversion error.
Performs the conversion.
The type returned in the event of a conversion error.
Performs the conversion.

Auto Trait Implementations

Blanket Implementations

Gets the TypeId of self. Read more
Immutably borrows from an owned value. Read more
Mutably borrows from an owned value. Read more

Returns the argument unchanged.

Calls U::from(self).

That is, this conversion is whatever the implementation of From<T> for U chooses to do.

Should always be Self
Encode the hex strict representing self into the result. Lower case letters are used (e.g. f9b4ca) Read more
Encode the hex strict representing self into the result. Upper case letters are used (e.g. F9B4CA) Read more
The resulting type after obtaining ownership.
Creates owned data from borrowed data, usually by cloning. Read more
Uses borrowed data to replace owned data, usually by cloning. Read more
Converts the given value to a String. Read more
The type returned in the event of a conversion error.
Performs the conversion.
The type returned in the event of a conversion error.
Performs the conversion.