Add support for application/x-www-form-urlencoded

src/request.rs

@@ -1,9 +1,10 @@
+use std::borrow::Borrow;
 use std::io::Read;
 use std::sync::{Arc, Mutex};
 
 use lazy_static::lazy_static;
 use qstring::QString;
-use url::Url;
+use url::{form_urlencoded, Url};
 
 use crate::agent::{self, Agent, AgentState};
 use crate::body::Payload;
@@ -181,6 +182,37 @@ impl Request {
         self.do_call(Payload::Text(text, charset))
     }
 
+    /// Send a sequence of (key, value) pairs as form-urlencoded data.
+    ///
+    /// The `Content-Type` header is implicitly set to application/x-www-form-urlencoded.
+    /// The `Content-Length` header is implicitly set to the length of the serialized value.
+    ///
+    /// ```
+    /// #[macro_use]
+    /// extern crate ureq;
+    ///
+    /// fn main() {
+    /// let r = ureq::post("/my_page")
+    ///     .send_form(&[("foo", "bar"),("foo2", "bar2")]);
+    /// println!("{:?}", r);
+    /// }
+    /// ```
+    pub fn send_form<I, K, V>(&mut self, pairs: I) -> Response
+    where
+        I: IntoIterator,
+        I::Item: Borrow<(K, V)>,
+        K: AsRef<str>,
+        V: AsRef<str>,
+    {
+        if self.header("Content-Type").is_none() {
+            self.set("Content-Type", "application/x-www-form-urlencoded");
+        }
+        let encoded = form_urlencoded::Serializer::new(String::new())
+            .extend_pairs(pairs)
+            .finish();
+        self.do_call(Payload::Bytes(encoded.into_bytes()))
+    }
+
     /// Send data from a reader.
     ///
     /// The `Content-Length` header is not set because we can't know the length of the reader.