Struct cbor_data::CborOwned

pub struct CborOwned(_);

Wrapper around a vector of bytes, for parsing as CBOR.

For details on the format see RFC 8949.

When interpreting CBOR messages from the outside (e.g. from the network) it is advisable to ingest those using the canonical constructor. In case the message was encoded for example using CborBuilder it is sufficient to use the trusting constructor.

Canonicalisation rqeuires an intermediary data buffer, which can be supplied (and reused) by the caller to save on allocations.

Implementations

impl CborOwned

pub fn unchecked(bytes: impl Into<SmallVec<[u8; 16]>>) -> Self

Copy the bytes and wrap for indexing.

No checks on the integrity are made, indexing methods may panic if encoded lengths are out of bound. If you want to carefully treat data obtained from unreliable sources, prefer canonical().

pub fn canonical(bytes: impl AsRef<[u8]>) -> Result<Self, ParseError>

Copy the bytes while checking for integrity and replacing indefinite (byte) strings with definite ones.

This constructor will go through and decode the whole provided CBOR bytes and write them into a vector, thereby

• writing large arrays and dicts using indefinite size format
• writing numbers in their smallest form

For more configuration options like reusing a scratch space or preferring definite size encoding see CborBuilder.

Methods from Deref<Target = Cbor>

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

A view onto the underlying bytes

pub fn decode(&self) -> CborValue<'_>

Interpret the CBOR item at a higher level

While kind gives you precise information on how the item is encoded, this method interprets the tag-based encoding according to the standard, adding for example big integers, decimals, and floats, or turning base64-encoded text strings into binary strings.

pub fn tags(&self) -> Tags<'_>

An iterator over the tags present on this item, from outermost to innermost

pub fn kind(&self) -> ItemKind<'_>

The low-level encoding of this item, without its tags

pub fn tagged_item(&self) -> TaggedItem<'_>

The low-level encoding of this item with its tags

pub fn index<'a, 'b>(
    &'a self,
    path: impl IntoIterator<Item = PathElement<'b>>
) -> Option<Cow<'a, Cbor>>

Extract a value by indexing into arrays and dicts, with path elements yielded by an iterator.

Returns None if an index doesn’t exist or the indexed object is neither an array nor a dict. When the object under consideration is an array, the next path element must represent an integer number.

Providing an empty iterator will yield the current Cbor item.

Returns a borrowed Cbor unless the traversal entered a TAG_CBOR_ITEM byte string with indefinite encoding (in which case the bytes need to be assembled into a Vec before continuing). This cannot happen if the item being indexed stems from CborOwned::canonical.

pub fn index_borrowed<'a, 'b>(
    &'a self,
    path: impl IntoIterator<Item = PathElement<'b>>
) -> Option<&'a Cbor>

Extract a value by indexing into arrays and dicts, with path elements yielded by an iterator.

Returns None if an index doesn’t exist or the indexed object is neither an array nor a dict. When the object under consideration is an array, the next path element must represent an integer number.

Providing an empty iterator will yield the current Cbor item.

Panics

Panics if this CBOR item contains a TAG_CBOR_ITEM byte string that has been index into by this path traversal. Use CborOwned::canonical to ensure that this cannot happen.

pub fn visit<'a, 'b, Err, V: Visitor<'a, Err> + 'b>(
    &'a self,
    visitor: &'b mut V
) -> Result<(), Err>

Visit the interesting parts of this CBOR item as guided by the given Visitor.

Returns false if the visit was not even begun due to invalid or non-canonical CBOR.

Trait Implementations

impl AsRef<[u8]> for CborOwned

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

Performs the conversion.

impl AsRef<Cbor> for CborOwned

fn as_ref(&self) -> &Cbor

Performs the conversion.

impl Borrow<Cbor> for CborOwned

fn borrow(&self) -> &Cbor

Immutably borrows from an owned value.

impl Clone for CborOwned

fn clone(&self) -> CborOwned

Returns a copy of the value.

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

Performs copy-assignment from source.

impl Debug for CborOwned

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

Formats the value using the given formatter.

impl Deref for CborOwned

type Target = Cbor

The resulting type after dereferencing.

fn deref(&self) -> &Self::Target

Dereferences the value.

impl Display for CborOwned

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

Formats the value using the given formatter.

impl Hash for CborOwned

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

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 CborOwned

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

This method returns an Ordering between self and other.

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

Compares and returns the maximum of two values.

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

Compares and returns the minimum of two values.

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

Restrict a value to a certain interval.

impl PartialEq<CborOwned> for CborOwned

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

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

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

This method tests for !=.

impl PartialOrd<CborOwned> for CborOwned

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

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

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

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

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

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

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

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

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 TryFrom<&'_ [u8]> for CborOwned

type Error = ParseError

The type returned in the event of a conversion error.

fn try_from(value: &[u8]) -> Result<Self, Self::Error>

Performs the conversion.

impl Eq for CborOwned

impl StructuralEq for CborOwned

impl StructuralPartialEq for CborOwned