//! The HTTP request method
use std::fmt;
use std::str::FromStr;
use self::Method::{Options, Get, Post, Put, Delete, Head, Trace, Connect, Patch,
Extension};
/// The Request Method (VERB)
///
/// Currently includes 8 variants representing the 8 methods defined in
/// [RFC 7230](https://tools.ietf.org/html/rfc7231#section-4.1), plus PATCH,
/// and an Extension variant for all extensions.
///
/// It may make sense to grow this to include all variants currently
/// registered with IANA, if they are at all common to use.
#[deriving(Clone, PartialEq)]
pub enum Method {
/// OPTIONS
Options,
/// GET
Get,
/// POST
Post,
/// PUT
Put,
/// DELETE
Delete,
/// HEAD
Head,
/// TRACE
Trace,
/// CONNECT
Connect,
/// PATCH
Patch,
/// Method extentions. An example would be `let m = Extension("FOO".to_string())`.
Extension(String)
}
impl Method {
/// Whether a method is considered "safe", meaning the request is
/// essentially read-only.
///
/// See [the spec](https://tools.ietf.org/html/rfc7231#section-4.2.1)
/// for more words.
pub fn safe(&self) -> bool {
match *self {
Get | Head | Options | Trace => true,
_ => false
}
}
/// Whether a method is considered "idempotent", meaning the request has
/// the same result is executed multiple times.
///
/// See [the spec](https://tools.ietf.org/html/rfc7231#section-4.2.2) for
/// more words.
pub fn idempotent(&self) -> bool {
if self.safe() {
true
} else {
match *self {
Put | Delete => true,
_ => false
}
}
}
}
impl FromStr for Method {
fn from_str(s: &str) -> Option<Method> {
Some(match s {
"OPTIONS" => Options,
"GET" => Get,
"POST" => Post,
"PUT" => Put,
"DELETE" => Delete,
"HEAD" => Head,
"TRACE" => Trace,
"CONNECT" => Connect,
"PATCH" => Patch,
_ => Extension(s.to_string())
})
}
}
impl fmt::Show for Method {
fn fmt(&self, fmt: &mut fmt::Formatter) -> fmt::Result {
match *self {
Options => "OPTIONS",
Get => "GET",
Post => "POST",
Put => "PUT",
Delete => "DELETE",
Head => "HEAD",
Trace => "TRACE",
Connect => "CONNECT",
Patch => "PATCH",
Extension(ref s) => s.as_slice()
}.fmt(fmt)
}
}