fix: incorrect json response content type

tests/basic.rs

@@ -15,6 +15,8 @@ use serde_json::json;
 use std::net::SocketAddr;
 use validator::Validate;
 
+mod utils;
+
 mod route {
     pub const PATH: &str = "/path/:v0/:v1";
     pub const QUERY: &str = "/query";
@@ -78,10 +80,7 @@ async fn main() -> anyhow::Result<()> {
         .await?;
     assert_eq!(invalid_path_response.status(), VALIDATION_ERROR_STATUS);
     #[cfg(feature = "into_json")]
-    assert!(invalid_path_response
-        .json::<serde_json::Value>()
-        .await
-        .is_ok());
+    utils::check_json(invalid_path_response).await;
     println!("Valid<Path<...>> works.");
 
     // Valid<Query<...>>
@@ -107,10 +106,7 @@ async fn main() -> anyhow::Result<()> {
         .await?;
     assert_eq!(invalid_query_response.status(), VALIDATION_ERROR_STATUS);
     #[cfg(feature = "into_json")]
-    assert!(invalid_query_response
-        .json::<serde_json::Value>()
-        .await
-        .is_ok());
+    utils::check_json(invalid_query_response).await;
     println!("Valid<Query<...>> works.");
 
     // Valid<Form<...>>
@@ -139,10 +135,7 @@ async fn main() -> anyhow::Result<()> {
         .await?;
     assert_eq!(invalid_form_response.status(), VALIDATION_ERROR_STATUS);
     #[cfg(feature = "into_json")]
-    assert!(invalid_form_response
-        .json::<serde_json::Value>()
-        .await
-        .is_ok());
+    utils::check_json(invalid_form_response).await;
     println!("Valid<Form<...>> works.");
 
     // Valid<Json<...>>
@@ -171,10 +164,7 @@ async fn main() -> anyhow::Result<()> {
         .await?;
     assert_eq!(invalid_json_response.status(), VALIDATION_ERROR_STATUS);
     #[cfg(feature = "into_json")]
-    assert!(invalid_json_response
-        .json::<serde_json::Value>()
-        .await
-        .is_ok());
+    utils::check_json(invalid_json_response).await;
     println!("Valid<Json<...>> works.");
 
     drop(server_guard);

tests/custom.rs

@@ -12,6 +12,8 @@ use serde::{Deserialize, Serialize};
 use std::net::SocketAddr;
 use validator::Validate;
 
+mod utils;
+
 const MY_DATA_HEADER: &str = "My-Data";
 
 // 1. Implement your own extractor.
@@ -124,10 +126,7 @@ async fn main() -> anyhow::Result<()> {
         .await?;
     assert_eq!(invalid_my_data_response.status(), VALIDATION_ERROR_STATUS);
     #[cfg(feature = "into_json")]
-    assert!(invalid_my_data_response
-        .json::<serde_json::Value>()
-        .await
-        .is_ok());
+    utils::check_json(invalid_my_data_response).await;
     println!("Valid<MyData> works.");
 
     drop(server_guard);

tests/utils.rs

@@ -0,0 +1,9 @@
+/// Check if the response is a json response
+#[cfg(feature = "into_json")]
+pub async fn check_json(response: reqwest::Response) {
+    assert_eq!(
+        response.headers()[axum::http::header::CONTENT_TYPE],
+        axum::http::HeaderValue::from_static(mime::APPLICATION_JSON.as_ref())
+    );
+    assert!(response.json::<serde_json::Value>().await.is_ok());
+}