Struct Statement 

pub struct Statement { /* private fields */ }

Statement structure.

Implementations

impl Statement

pub fn new() -> Statement

Create a new empty statement with no proof.

pub fn new_with_proof(proof: Proof) -> Statement

Create a new statement with a proof.

pub fn sign_sr25519_public(&mut self, key: &Public) -> bool

Sign with a key that matches given public key in the keystore.

Returns true if signing worked (private key present etc).

NOTE: This can only be called from the runtime.

pub fn topics(&self) -> &[Topic]

Returns slice of all topics set in the statement.

pub fn sign_sr25519_private(&mut self, key: &Pair)

Sign with a given private key and add the signature proof field.

pub fn sign_ed25519_public(&mut self, key: &Public) -> bool

Sign with a key that matches given public key in the keystore.

Returns true if signing worked (private key present etc).

NOTE: This can only be called from the runtime.

pub fn sign_ed25519_private(&mut self, key: &Pair)

Sign with a given private key and add the signature proof field.

pub fn sign_ecdsa_public(&mut self, key: &Public) -> bool

Sign with a key that matches given public key in the keystore.

Returns true if signing worked (private key present etc).

NOTE: This can only be called from the runtime.

pub fn sign_ecdsa_private(&mut self, key: &Pair)

Sign with a given private key and add the signature proof field.

pub fn verify_signature(&self) -> SignatureVerificationResult

Verify the proof’s signature over the statement’s signature material (all fields except the proof itself).

Returns SignatureVerificationResult::NoSignature when there is no proof. On success the returned account is the signer for sr25519/ed25519, but for ECDSA it is the BLAKE2-256 hash of the signer key, not the key itself.

pub fn hash(&self) -> [u8; 32]

The statement’s hash: the BLAKE2-256 hash of its SCALE encoding.

This is the statement’s identity for deduplication and indexing across the store and network. It covers the full encoding (including the proof), so changing any field changes the hash.

pub fn topic(&self, index: usize) -> Option<Topic>

Returns a topic by topic index.

pub fn decryption_key(&self) -> Option<DecryptionKey>

Returns decryption key if any.

pub fn into_data(self) -> Option<Vec<u8>>

Consume the statement and return its data field (see data).

pub fn proof(&self) -> Option<&Proof>

Get a reference to the statement proof, if any.

pub fn account_id(&self) -> Option<AccountId>

Get proof account id, if any

pub fn data(&self) -> Option<&Vec<u8>>

Returns the statement’s data field, if any. The bytes are plaintext when set via set_plain_data or ciphertext when set via encrypt.

pub fn data_len(&self) -> usize

Length in bytes of the statement’s data field (0 if absent).

This is the size the per-account quota (StatementAllowance::max_size) is measured against — the data length, not the full SCALE-encoded statement size.

pub fn channel(&self) -> Option<Channel>

Get channel, if any.

pub fn expiry(&self) -> u64

Get expiry.

pub fn get_expiration_timestamp_secs(&self) -> u32

Get expiration timestamp in seconds.

The expiration timestamp in seconds is stored in the most significant 32 bits of the expiry field.

pub fn is_expired(&self, now_secs: u64) -> bool

Whether the statement has expired at now_secs, a unix timestamp in seconds.

Expired once now_secs reaches the expiration timestamp.

pub fn remove_proof(&mut self)

Remove the proof of this statement.

pub fn set_proof(&mut self, proof: Proof)

Set statement proof. Any existing proof is overwritten.

pub fn set_expiry(&mut self, expiry: u64)

Set statement expiry.

pub fn set_expiry_from_parts( &mut self, expiration_timestamp_secs: u32, sequence_number: u32, )

Set statement expiry from its parts. See Statement::expiry for details on the format.

pub fn set_channel(&mut self, channel: Channel)

Set statement channel.

pub fn set_topic(&mut self, index: usize, topic: Topic)

Set topic by index. Does nothing if index is at or beyond MAX_TOPICS.

Grows the statement’s topic count so that index becomes addressable.

pub fn set_decryption_key(&mut self, key: DecryptionKey)

Set decryption key.

pub fn set_plain_data(&mut self, data: Vec<u8>)

Set unencrypted statement data.

pub fn encrypt(&mut self, data: &[u8], key: &Public) -> Result<(), Error>

Encrypt data to key (ECIES) and store both the ciphertext and the matching decryption key on the statement.

Note: encryption is experimental (the decryption-key field is deprecated).

pub fn decrypt_private(&self, key: &Pair) -> Result<Option<Vec<u8>>, Error>

Decrypt the statement’s data with the given private key (ECIES).

Returns Ok(None) if the statement has no data; errors if the data was not encrypted to this key.

Trait Implementations

impl Clone for Statement

fn clone(&self) -> Self

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for Statement

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

Formats the value using the given formatter.

impl Decode for Statement

fn decode<I: Input>(input: &mut I) -> Result<Self, Error>

Attempt to deserialise the value from input.

fn decode_into<I>( input: &mut I, dst: &mut MaybeUninit<Self>, ) -> Result<DecodeFinished, Error>

where I: Input,

Attempt to deserialize the value from input into a pre-allocated piece of memory.

fn skip<I>(input: &mut I) -> Result<(), Error>

where I: Input,

Attempt to skip the encoded value from input.

fn encoded_fixed_size() -> Option<usize>

Returns the fixed encoded size of the type.

impl DecodeWithMemTracking for Statement

impl Default for Statement

fn default() -> Self

Returns the “default value” for a type.

impl Encode for Statement

fn encode(&self) -> Vec<u8>

Convert self to an owned vector.

fn size_hint(&self) -> usize

If possible give a hint of expected size of the encoding.

fn encode_to<T>(&self, dest: &mut T)

where T: Output + ?Sized,

Convert self to a slice and append it to the destination.

fn using_encoded<R, F>(&self, f: F) -> R

where F: FnOnce(&[u8]) -> R,

Convert self to a slice and then invoke the given closure with it.

fn encoded_size(&self) -> usize

Calculates the encoded size.

impl Eq for Statement

impl PartialEq for Statement

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

Equality operator ==.

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

Inequality operator !=.

impl StructuralPartialEq for Statement

impl TypeInfo for Statement

Note: The TypeInfo implementation reflects the actual encoding format (Vec<Field>) rather than the struct fields, since Statement has custom Encode/Decode implementations.

type Identity = Statement

The type identifying for which type info is provided.

fn type_info() -> Type

Returns the static type identifier for Self.