http-types/src/content/content_length.rs

104 lines
2.7 KiB
Rust

use crate::headers::{Header, HeaderName, HeaderValue, Headers, CONTENT_LENGTH};
use crate::Status;
/// The size of the entity-body, in bytes, sent to the recipient.
///
/// # Specifications
///
/// - [RFC 7230, section 3.3.2: Content-Length](https://tools.ietf.org/html/rfc7230#section-3.3.2)
///
/// # Examples
///
/// ```
/// # fn main() -> http_types::Result<()> {
/// #
/// use http_types::Response;
/// use http_types::content::{ContentLength};
///
/// let content_len = ContentLength::new(12);
///
/// let mut res = Response::new(200);
/// res.insert_header(&content_len, &content_len);
///
/// let content_len = ContentLength::from_headers(res)?.unwrap();
/// assert_eq!(content_len.len(), 12);
/// #
/// # Ok(()) }
/// ```
#[derive(Debug)]
pub struct ContentLength {
length: u64,
}
#[allow(clippy::len_without_is_empty)]
impl ContentLength {
/// Create a new instance.
pub fn new(length: u64) -> Self {
Self { length }
}
/// Create a new instance from headers.
pub fn from_headers(headers: impl AsRef<Headers>) -> crate::Result<Option<Self>> {
let headers = match headers.as_ref().get(CONTENT_LENGTH) {
Some(headers) => headers,
None => return Ok(None),
};
// If we successfully parsed the header then there's always at least one
// entry. We want the last entry.
let value = headers.iter().last().unwrap();
let length = value.as_str().trim().parse().status(400)?;
Ok(Some(Self { length }))
}
/// Get the content length.
pub fn len(&self) -> u64 {
self.length
}
/// Set the content length.
pub fn set_len(&mut self, len: u64) {
self.length = len;
}
}
impl Header for ContentLength {
fn header_name(&self) -> HeaderName {
CONTENT_LENGTH
}
fn header_value(&self) -> HeaderValue {
let output = format!("{}", self.length);
// SAFETY: the internal string is validated to be ASCII.
unsafe { HeaderValue::from_bytes_unchecked(output.into()) }
}
}
#[cfg(test)]
mod test {
use super::*;
use crate::headers::Headers;
#[test]
fn smoke() -> crate::Result<()> {
let content_len = ContentLength::new(12);
let mut headers = Headers::new();
content_len.apply_header(&mut headers);
let content_len = ContentLength::from_headers(headers)?.unwrap();
assert_eq!(content_len.len(), 12);
Ok(())
}
#[test]
fn bad_request_on_parse_error() {
let mut headers = Headers::new();
headers
.insert(CONTENT_LENGTH, "<nori ate the tag. yum.>")
.unwrap();
let err = ContentLength::from_headers(headers).unwrap_err();
assert_eq!(err.status(), 400);
}
}