implementation

src/method.rs

@@ -0,0 +1,99 @@
+//! # HTTP Method
+use std::fmt;
+use std::from_str::FromStr;
+
+/// 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)
+    }
+}