1 files changed, 18 insertions, 0 deletions
diff --git a/components/shared/net/fetch/headers.rs b/components/shared/net/fetch/headers.rs
new file mode 100644
index 00000000000..ae95066bcf5
--- /dev/null
+++ b/components/shared/net/fetch/headers.rs
@@ -0,0 +1,18 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at https://mozilla.org/MPL/2.0/. */
+
+use headers::HeaderMap;
+
+/// <https://fetch.spec.whatwg.org/#concept-header-list-get>
+pub fn get_value_from_header_list(name: &str, headers: &HeaderMap) -> Option<Vec<u8>> {
+    let values = headers.get_all(name).iter().map(|val| val.as_bytes());
+
+    // Step 1
+    if values.size_hint() == (0, Some(0)) {
+        return None;
+    }
+
+    // Step 2
+    return Some(values.collect::<Vec<&[u8]>>().join(&[0x2C, 0x20][..]));
+}