1 files changed, 68 insertions, 0 deletions
diff --git a/third_party/rust/headers/src/common/allow.rs b/third_party/rust/headers/src/common/allow.rs
new file mode 100644
index 0000000000..0285d3c780
--- /dev/null
+++ b/third_party/rust/headers/src/common/allow.rs
@@ -0,0 +1,68 @@
+use std::iter::FromIterator;
+
+use http::Method;
+
+use util::FlatCsv;
+
+/// `Allow` header, defined in [RFC7231](http://tools.ietf.org/html/rfc7231#section-7.4.1)
+///
+/// The `Allow` header field lists the set of methods advertised as
+/// supported by the target resource.  The purpose of this field is
+/// strictly to inform the recipient of valid request methods associated
+/// with the resource.
+///
+/// # ABNF
+///
+/// ```text
+/// Allow = #method
+/// ```
+///
+/// # Example values
+/// * `GET, HEAD, PUT`
+/// * `OPTIONS, GET, PUT, POST, DELETE, HEAD, TRACE, CONNECT, PATCH, fOObAr`
+/// * ``
+///
+/// # Examples
+///
+/// ```
+/// # extern crate headers;
+/// extern crate http;
+/// use headers::Allow;
+/// use http::Method;
+///
+/// let allow = vec![Method::GET, Method::POST]
+///     .into_iter()
+///     .collect::<Allow>();
+/// ```
+#[derive(Clone, Debug, PartialEq)]
+pub struct Allow(FlatCsv);
+
+derive_header! {
+    Allow(_),
+    name: ALLOW
+}
+
+impl Allow {
+    /// Returns an iterator over `Method`s contained within.
+    pub fn iter<'a>(&'a self) -> impl Iterator<Item = Method> + 'a {
+        self.0.iter().filter_map(|s| s.parse().ok())
+    }
+}
+
+impl FromIterator<Method> for Allow {
+    fn from_iter<I>(iter: I) -> Self
+    where
+        I: IntoIterator<Item = Method>,
+    {
+        let flat = iter
+            .into_iter()
+            .map(|method| {
+                method
+                    .as_str()
+                    .parse::<::HeaderValue>()
+                    .expect("Method is a valid HeaderValue")
+            })
+            .collect();
+        Allow(flat)
+    }
+}