Expose the default headers used by clients

src/async_impl/client.rs

@@ -84,7 +84,7 @@ pub struct Client {
 /// A `ClientBuilder` can be used to create a `Client` with custom configuration.
 #[must_use]
 pub struct ClientBuilder {
-    config: Config,
+    pub(crate) config: Config,
 }
 
 enum HttpVersionPref {
@@ -117,10 +117,10 @@ impl Service<hyper::Request<crate::async_impl::body::Body>> for HyperService {
     }
 }
 
-struct Config {
+pub(crate) struct Config {
     // NOTE: When adding a new field, update `fmt::Debug for ClientBuilder`
     accepts: Accepts,
-    headers: HeaderMap,
+    pub(crate) headers: HeaderMap,
     #[cfg(feature = "__tls")]
     hostname_verification: bool,
     #[cfg(feature = "__tls")]
@@ -2379,6 +2379,11 @@ impl Client {
         ClientBuilder::new()
     }
 
+    /// Get the headers this `Client` will add to all its `Request`s.
+    pub fn headers(&self) -> &crate::header::HeaderMap {
+        &self.inner.as_ref().headers
+    }
+
     /// Convenience method to make a `GET` request to a URL.
     ///
     /// # Errors

src/blocking/client.rs

@@ -1226,6 +1226,11 @@ impl Client {
         ClientBuilder::new()
     }
 
+    /// Get the headers this `Client` will add to all its `Request`s.
+    pub fn headers(&self) -> &crate::header::HeaderMap {
+        &self.inner.headers
+    }
+
     /// Convenience method to make a `GET` request to a URL.
     ///
     /// # Errors
@@ -1329,6 +1334,7 @@ impl fmt::Debug for ClientBuilder {
 #[derive(Clone)]
 struct ClientHandle {
     timeout: Timeout,
+    headers: crate::header::HeaderMap,
     inner: Arc<InnerClientHandle>,
 }
 
@@ -1359,6 +1365,7 @@ impl Drop for InnerClientHandle {
 impl ClientHandle {
     fn new(builder: ClientBuilder) -> crate::Result<ClientHandle> {
         let timeout = builder.timeout;
+        let headers = builder.inner.config.headers.clone();
         let builder = builder.inner;
         let (tx, rx) = mpsc::unbounded_channel::<(async_impl::Request, OneshotResponse)>();
         let (spawn_tx, spawn_rx) = oneshot::channel::<crate::Result<()>>();
@@ -1427,6 +1434,7 @@ impl ClientHandle {
 
         Ok(ClientHandle {
             timeout,
+            headers,
             inner: inner_handle,
         })
     }

tests/blocking.rs

@@ -216,6 +216,8 @@ fn test_default_headers() {
     let url = format!("http://{}/1", server.addr());
     let res = client.get(&url).send().unwrap();
 
+    assert_eq!(client.headers()["reqwest-test"], "orly");
+
     assert_eq!(res.url().as_str(), &url);
     assert_eq!(res.status(), reqwest::StatusCode::OK);
 }
@@ -250,6 +252,8 @@ fn test_override_default_headers() {
         .send()
         .unwrap();
 
+    assert_eq!(client.headers()[&http::header::AUTHORIZATION], "iamatoken");
+
     assert_eq!(res.url().as_str(), &url);
     assert_eq!(res.status(), reqwest::StatusCode::OK);
 }
@@ -275,6 +279,10 @@ fn test_appended_headers_not_overwritten() {
         .send()
         .unwrap();
 
+    let mut accepts = client.headers().get_all("accept").into_iter();
+    assert_eq!(accepts.next().unwrap(), "*/*");
+    assert_eq!(accepts.next(), None);
+
     assert_eq!(res.url().as_str(), &url);
     assert_eq!(res.status(), reqwest::StatusCode::OK);
 
@@ -298,6 +306,10 @@ fn test_appended_headers_not_overwritten() {
         .send()
         .unwrap();
 
+    let mut accepts = client.headers().get_all("accept").into_iter();
+    assert_eq!(accepts.next().unwrap(), "text/html");
+    assert_eq!(accepts.next(), None);
+
     assert_eq!(res.url().as_str(), &url);
     assert_eq!(res.status(), reqwest::StatusCode::OK);
 }

tests/client.rs

@@ -47,14 +47,11 @@ async fn auto_headers() {
     });
 
     let url = format!("http://{}/1", server.addr());
-    let res = reqwest::Client::builder()
-        .no_proxy()
-        .build()
-        .unwrap()
-        .get(&url)
-        .send()
-        .await
-        .unwrap();
+    let client = reqwest::Client::builder().no_proxy().build().unwrap();
+    let res = client.get(&url).send().await.unwrap();
+
+    assert_eq!(client.headers()["accept"], "*/*");
+    assert_eq!(client.headers().get("user-agent"), None);
 
     assert_eq!(res.url().as_str(), &url);
     assert_eq!(res.status(), reqwest::StatusCode::OK);
@@ -93,14 +90,13 @@ async fn user_agent() {
     });
 
     let url = format!("http://{}/ua", server.addr());
-    let res = reqwest::Client::builder()
+    let client = reqwest::Client::builder()
         .user_agent("reqwest-test-agent")
         .build()
-        .expect("client builder")
-        .get(&url)
-        .send()
-        .await
-        .expect("request");
+        .expect("client builder");
+    let res = client.get(&url).send().await.expect("request");
+
+    assert_eq!(client.headers()["user-agent"], "reqwest-test-agent");
 
     assert_eq!(res.status(), reqwest::StatusCode::OK);
 }