Struct Headers 

pub struct Headers {
    pub limit: usize,
    pub remaining: usize,
    pub reset: ResetTime,
    pub window: Option<Duration>,
    pub vendor: Vendor,
    pub candidates: VendorMask,
}

HTTP rate limits as parsed from header values

Fields

limit: usize

The maximum number of requests allowed in the time window

remaining: usize

The number of requests remaining in the time window

reset: ResetTime

The time at which the rate limit will be reset

window: Option<Duration>

The time window until the rate limit is lifted. It is marked optional, because it might not be provided, in which case it needs to be inferred from the context

vendor: Vendor

Predicted vendor based on rate limit header

candidates: VendorMask

All candidates that matched the headers

Implementations

impl Headers

pub fn new(headers: &HeaderMap) -> Result<Self, Error>

Extracts rate limits from an iterator of HTTP headers.

Different vendors (e.g. GitHub, Vimeo, Twitter) use different header names. This function attempts to identify the vendor based on the presence of known headers.

There are many websites abusing or reusing rate limit headers with their own definition of what the values mean. This library tries to be pessimistic and only attempts to parse the rate limit headers if it trusts the website to follow one of the supported variants.

Some vendors might use the same header names but different value formats. In this case, the library will try to parse the headers using the different variants until one succeeds.

When parsing headers, casing is significant. For example, GitHub uses “x-ratelimit-remaining” while Reddit uses “X-Ratelimit-Remaining.” This is also why we use an iterator of header key-value pairs instead of a case-insensitive map like http::HeaderMap.

Errors

Returns an error if the headers do not contain a known rate limit format, or if the header values cannot be parsed.

pub fn extract<'a, I>(headers: I) -> Result<Self, Error>

where I: IntoIterator<Item = (&'a str, &'a str)>,

Extracts rate limits from an iterator of HTTP headers.

pub const fn limit(&self) -> usize

Get the number of requests allowed in the time window

pub const fn remaining(&self) -> usize

Get the number of requests remaining in the time window

pub const fn reset(&self) -> ResetTime

Get the time at which the rate limit will be reset

Trait Implementations

impl Clone for Headers

fn clone(&self) -> Headers

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for Headers

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

Formats the value using the given formatter.

impl FromStr for Headers

type Err = Error

The associated error which can be returned from parsing.

fn from_str(map: &str) -> Result<Self, Error>

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

impl PartialEq for Headers

fn eq(&self, other: &Headers) -> 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 Copy for Headers

impl StructuralPartialEq for Headers