Enum ByteRangeSpec

pub enum ByteRangeSpec {
    FromTo(u64, u64),
    From(u64),
    Last(u64),
}

A range of bytes to fetch.

Each Range::Bytes header can contain one or more ByteRangeSpecs.

Variants

FromTo(u64, u64)

All bytes from x to y, inclusive.

Serialized as x-y.

Example: bytes=500-999 would represent the second 500 bytes.

From(u64)

All bytes starting from x, inclusive.

Serialized as x-.

Example: For a file of 1000 bytes, bytes=950- would represent bytes 950-999, inclusive.

Last(u64)

The last y bytes, inclusive.

Using the spec terminology, this is suffix-byte-range-spec. Serialized as -y.

Example: For a file of 1000 bytes, bytes=-50 is equivalent to bytes=950-.

Implementations

impl ByteRangeSpec

pub fn to_satisfiable_range(&self, full_length: u64) -> Option<(u64, u64)>

Given the full length of the entity, attempt to normalize the byte range into an satisfiable end-inclusive (from, to) range.

The resulting range is guaranteed to be a satisfiable range within the bounds of 0 <= from <= to < full_length.

If the byte range is deemed unsatisfiable, None is returned. An unsatisfiable range is generally cause for a server to either reject the client request with a 416 Range Not Satisfiable status code, or to simply ignore the range header and serve the full entity using a 200 OK status code.

This function closely follows RFC 7233 §2.1. As such, it considers ranges to be satisfiable if they meet the following conditions:

If a valid byte-range-set includes at least one byte-range-spec with a first-byte-pos that is less than the current length of the representation, or at least one suffix-byte-range-spec with a non-zero suffix-length, then the byte-range-set is satisfiable. Otherwise, the byte-range-set is unsatisfiable.

The function also computes remainder ranges based on the RFC:

If the last-byte-pos value is absent, or if the value is greater than or equal to the current length of the representation data, the byte range is interpreted as the remainder of the representation (i.e., the server replaces the value of last-byte-pos with a value that is one less than the current length of the selected representation).

Trait Implementations

impl Clone for ByteRangeSpec

fn clone(&self) -> ByteRangeSpec

Returns a copy of the value.

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

Performs copy-assignment from source.

impl Debug for ByteRangeSpec

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

Formats the value using the given formatter.

impl Display for ByteRangeSpec

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

Formats the value using the given formatter.

impl FromStr for ByteRangeSpec

type Err = ParseError

The associated error which can be returned from parsing.

fn from_str(s: &str) -> Result<ByteRangeSpec, ParseError>

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

impl PartialEq for ByteRangeSpec

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

Tests for self and other values to be equal, and is used by ==.

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

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl Eq for ByteRangeSpec

impl StructuralPartialEq for ByteRangeSpec