Convert ViolationCode into ViolationVariant to allow adding fields on each variant

crates/handlers/src/compat/login.rs

@@ -16,7 +16,7 @@ use mas_data_model::{
     User,
 };
 use mas_matrix::HomeserverConnection;
-use mas_policy::{Policy, Requester, ViolationCode, model::CompatLogin};
+use mas_policy::{Policy, Requester, ViolationVariant, model::CompatLogin};
 use mas_storage::{
     BoxRepository, BoxRepositoryFactory, RepositoryAccess,
     compat::{
@@ -605,7 +605,7 @@ async fn token_login(
         // that removing a session wouldn't actually unblock the login.
         if res.violations.len() == 1 {
             let violation = &res.violations[0];
-            if violation.code == Some(ViolationCode::TooManySessions) {
+            if violation.variant == Some(ViolationVariant::TooManySessions) {
                 // The only violation is having reached the session limit.
                 return Err(RouteError::PolicyHardSessionLimitReached);
             }
@@ -738,7 +738,7 @@ async fn user_password_login(
         // that removing a session wouldn't actually unblock the login.
         if res.violations.len() == 1 {
             let violation = &res.violations[0];
-            if violation.code == Some(ViolationCode::TooManySessions) {
+            if violation.variant == Some(ViolationVariant::TooManySessions) {
                 // The only violation is having reached the session limit.
                 return Err(RouteError::PolicyHardSessionLimitReached);
             }

crates/handlers/src/upstream_oauth2/link.rs

@@ -1108,13 +1108,13 @@ pub(crate) async fn post(
                             form_state.add_error_on_field(
                                 mas_templates::UpstreamRegisterFormField::Username,
                                 FieldError::Policy {
-                                    code: violation.code.map(|c| c.as_str()),
+                                    code: violation.variant.map(|c| c.as_str()),
                                     message: violation.msg,
                                 },
                             );
                         }
                         _ => form_state.add_error_on_form(FormError::Policy {
-                            code: violation.code.map(|c| c.as_str()),
+                            code: violation.variant.map(|c| c.as_str()),
                             message: violation.msg,
                         }),
                     }

crates/handlers/src/views/register/password.rs

@@ -263,7 +263,7 @@ pub(crate) async fn post(
                 Some("email") => state.add_error_on_field(
                     RegisterFormField::Email,
                     FieldError::Policy {
-                        code: violation.code.map(|c| c.as_str()),
+                        code: violation.variant.map(|c| c.as_str()),
                         message: violation.msg,
                     },
                 ),
@@ -274,7 +274,7 @@ pub(crate) async fn post(
                     state.add_error_on_field(
                         RegisterFormField::Username,
                         FieldError::Policy {
-                            code: violation.code.map(|c| c.as_str()),
+                            code: violation.variant.map(|c| c.as_str()),
                             message: violation.msg,
                         },
                     );
@@ -282,12 +282,12 @@ pub(crate) async fn post(
                 Some("password") => state.add_error_on_field(
                     RegisterFormField::Password,
                     FieldError::Policy {
-                        code: violation.code.map(|c| c.as_str()),
+                        code: violation.variant.map(|c| c.as_str()),
                         message: violation.msg,
                     },
                 ),
                 _ => state.add_error_on_form(FormError::Policy {
-                    code: violation.code.map(|c| c.as_str()),
+                    code: violation.variant.map(|c| c.as_str()),
                     message: violation.msg,
                 }),
             }

crates/policy/src/lib.rs

@@ -19,9 +19,9 @@ use thiserror::Error;
 use tokio::io::{AsyncRead, AsyncReadExt};
 
 pub use self::model::{
-    AuthorizationGrantInput, ClientRegistrationInput, Code as ViolationCode, CompatLoginInput,
-    EmailInput, EvaluationResult, GrantType, RegisterInput, RegistrationMethod, Requester,
-    Violation,
+    AuthorizationGrantInput, ClientRegistrationInput, CompatLoginInput, EmailInput,
+    EvaluationResult, GrantType, RegisterInput, RegistrationMethod, Requester, Violation,
+    ViolationVariant,
 };
 
 #[derive(Debug, Error)]

crates/policy/src/model.rs

@@ -16,10 +16,11 @@ use oauth2_types::{registration::VerifiedClientMetadata, scope::Scope};
 use schemars::JsonSchema;
 use serde::{Deserialize, Serialize};
 
-/// A well-known policy code.
+/// Violation variants identified by a well-known policy code (under the `code`
+/// key).
 #[derive(Serialize, Deserialize, Debug, Clone, Copy, JsonSchema, PartialEq, Eq)]
-#[serde(rename_all = "kebab-case")]
-pub enum Code {
+#[serde(tag = "code", rename_all = "kebab-case")]
+pub enum ViolationVariant {
     /// The username is too short.
     UsernameTooShort,
 
@@ -54,7 +55,7 @@ pub enum Code {
     TooManySessions,
 }
 
-impl Code {
+impl ViolationVariant {
     /// Returns the code as a string
     #[must_use]
     pub fn as_str(&self) -> &'static str {
@@ -80,7 +81,9 @@ pub struct Violation {
     pub msg: String,
     pub redirect_uri: Option<String>,
     pub field: Option<String>,
-    pub code: Option<Code>,
+
+    #[serde(flatten)]
+    pub variant: Option<ViolationVariant>,
 }
 
 /// The result of a policy evaluation.

crates/templates/src/context.rs

@@ -29,7 +29,7 @@ use mas_data_model::{
 };
 use mas_i18n::DataLocale;
 use mas_iana::jose::JsonWebSignatureAlg;
-use mas_policy::{Violation, ViolationCode};
+use mas_policy::{Violation, ViolationVariant};
 use mas_router::{Account, GraphQL, PostAuthAction, UrlBuilder};
 use oauth2_types::scope::{OPENID, Scope};
 use rand::{
@@ -890,7 +890,7 @@ impl TemplateContext for CompatLoginPolicyViolationContext {
                     msg: "user has too many active sessions".to_owned(),
                     redirect_uri: None,
                     field: None,
-                    code: Some(ViolationCode::TooManySessions),
+                    variant: Some(ViolationVariant::TooManySessions),
                 }],
             },
         ])