axum: Use serde_html_form for Query and Form (#3594)

examples/Cargo.lock

@@ -298,9 +298,9 @@ dependencies = [
  "percent-encoding",
  "pin-project-lite",
  "serde_core",
+ "serde_html_form",
  "serde_json",
  "serde_path_to_error",
- "serde_urlencoded",
  "sha1",
  "sync_wrapper",
  "tokio",
@@ -1573,17 +1573,6 @@ dependencies = [
  "tracing-subscriber",
 ]
 
-[[package]]
-name = "example-query-params-with-empty-strings"
-version = "0.1.0"
-dependencies = [
- "axum",
- "http-body-util",
- "serde",
- "tokio",
- "tower",
-]
-
 [[package]]
 name = "example-readme"
 version = "0.1.0"
@@ -4068,6 +4057,19 @@ dependencies = [
  "syn",
 ]
 
+[[package]]
+name = "serde_html_form"
+version = "0.3.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "1a055051604d997ae4ddff53663d390c15e96adc3720f54d43d18a7fd944cc79"
+dependencies = [
+ "form_urlencoded",
+ "indexmap",
+ "itoa",
+ "ryu",
+ "serde_core",
+]
+
 [[package]]
 name = "serde_json"
 version = "1.0.140"

examples/query-params-with-empty-strings/Cargo.toml

@@ -1,12 +0,0 @@
-[package]
-name = "example-query-params-with-empty-strings"
-version = "0.1.0"
-edition = "2021"
-publish = false
-
-[dependencies]
-axum = { path = "../../axum" }
-http-body-util = "0.1.0"
-serde = { version = "1.0", features = ["derive"] }
-tokio = { version = "1.0", features = ["full"] }
-tower = { version = "0.5.2", features = ["util"] }

examples/query-params-with-empty-strings/src/main.rs

@@ -1,121 +0,0 @@
-//! Run with
-//!
-//! ```not_rust
-//! cargo run -p example-query-params-with-empty-strings
-//! ```
-
-use axum::{extract::Query, routing::get, Router};
-use serde::{de, Deserialize, Deserializer};
-use std::{fmt, str::FromStr};
-
-#[tokio::main]
-async fn main() {
-    let listener = tokio::net::TcpListener::bind("127.0.0.1:3000")
-        .await
-        .unwrap();
-    println!("listening on {}", listener.local_addr().unwrap());
-    axum::serve(listener, app()).await.unwrap();
-}
-
-fn app() -> Router {
-    Router::new().route("/", get(handler))
-}
-
-async fn handler(Query(params): Query<Params>) -> String {
-    format!("{params:?}")
-}
-
-/// See the tests below for which combinations of `foo` and `bar` result in
-/// which deserializations.
-///
-/// This example only shows one possible way to do this. [`serde_with`] provides
-/// another way. Use which ever method works best for you.
-///
-/// [`serde_with`]: https://docs.rs/serde_with/1.11.0/serde_with/rust/string_empty_as_none/index.html
-#[derive(Debug, Deserialize)]
-#[allow(dead_code)]
-struct Params {
-    #[serde(default, deserialize_with = "empty_string_as_none")]
-    foo: Option<i32>,
-    bar: Option<String>,
-}
-
-/// Serde deserialization decorator to map empty Strings to None,
-fn empty_string_as_none<'de, D, T>(de: D) -> Result<Option<T>, D::Error>
-where
-    D: Deserializer<'de>,
-    T: FromStr,
-    T::Err: fmt::Display,
-{
-    let opt = Option::<String>::deserialize(de)?;
-    match opt.as_deref() {
-        None | Some("") => Ok(None),
-        Some(s) => FromStr::from_str(s).map_err(de::Error::custom).map(Some),
-    }
-}
-
-#[cfg(test)]
-mod tests {
-    use super::*;
-    use axum::{body::Body, http::Request};
-    use http_body_util::BodyExt;
-    use tower::ServiceExt;
-
-    #[tokio::test]
-    async fn test_something() {
-        assert_eq!(
-            send_request_get_body("foo=1&bar=bar").await,
-            r#"Params { foo: Some(1), bar: Some("bar") }"#,
-        );
-
-        assert_eq!(
-            send_request_get_body("foo=&bar=bar").await,
-            r#"Params { foo: None, bar: Some("bar") }"#,
-        );
-
-        assert_eq!(
-            send_request_get_body("foo=&bar=").await,
-            r#"Params { foo: None, bar: Some("") }"#,
-        );
-
-        assert_eq!(
-            send_request_get_body("foo=1").await,
-            r#"Params { foo: Some(1), bar: None }"#,
-        );
-
-        assert_eq!(
-            send_request_get_body("bar=bar").await,
-            r#"Params { foo: None, bar: Some("bar") }"#,
-        );
-
-        assert_eq!(
-            send_request_get_body("foo=").await,
-            r#"Params { foo: None, bar: None }"#,
-        );
-
-        assert_eq!(
-            send_request_get_body("bar=").await,
-            r#"Params { foo: None, bar: Some("") }"#,
-        );
-
-        assert_eq!(
-            send_request_get_body("").await,
-            r#"Params { foo: None, bar: None }"#,
-        );
-    }
-
-    async fn send_request_get_body(query: &str) -> String {
-        let body = app()
-            .oneshot(
-                Request::builder()
-                    .uri(format!("/?{query}"))
-                    .body(Body::empty())
-                    .unwrap(),
-            )
-            .await
-            .unwrap()
-            .into_body();
-        let bytes = body.collect().await.unwrap().to_bytes();
-        String::from_utf8(bytes.to_vec()).unwrap()
-    }
-}