Allow parameters in UserInfo endpoint's response's content-type

crates/oidc-client/src/error.rs

@@ -451,9 +451,13 @@ pub enum UserInfoError {
     #[error("could not decoded response content-type: {0}")]
     DecodeResponseContentType(#[from] ToStrError),
 
+    /// The content-type is not valid.
+    #[error("invalid response content-type")]
+    InvalidResponseContentTypeValue,
+
     /// The content-type is not the one that was expected.
-    #[error("invalid response content-type {got:?}, expected {expected:?}")]
-    InvalidResponseContentType {
+    #[error("unexpected response content-type {got:?}, expected {expected:?}")]
+    UnexpectedResponseContentType {
         /// The expected content-type.
         expected: String,
         /// The returned content-type.

crates/oidc-client/src/requests/userinfo.rs

@@ -19,10 +19,11 @@
 use std::collections::HashMap;
 
 use bytes::Bytes;
-use headers::{Authorization, HeaderMapExt, HeaderValue};
-use http::header::{ACCEPT, CONTENT_TYPE};
+use headers::{Authorization, ContentType, HeaderMapExt, HeaderValue};
+use http::header::ACCEPT;
 use mas_http::CatchHttpCodesLayer;
 use mas_jose::claims;
+use mime::Mime;
 use serde_json::Value;
 use tower::{Layer, Service, ServiceExt};
 use url::Url;
@@ -98,16 +99,17 @@ pub async fn fetch_userinfo(
         .call(userinfo_request)
         .await?;
 
-    let content_type = userinfo_response
+    let content_type: Mime = userinfo_response
         .headers()
-        .get(CONTENT_TYPE)
+        .typed_try_get::<ContentType>()
+        .map_err(|_| UserInfoError::InvalidResponseContentTypeValue)?
         .ok_or(UserInfoError::MissingResponseContentType)?
-        .to_str()?;
+        .into();
 
-    if content_type != expected_content_type {
-        return Err(UserInfoError::InvalidResponseContentType {
+    if content_type.essence_str() != expected_content_type {
+        return Err(UserInfoError::UnexpectedResponseContentType {
             expected: expected_content_type.to_owned(),
-            got: content_type.to_owned(),
+            got: content_type.to_string(),
         });
     }