Form error state overhaul

This adds a new FormState structure here to hold the state of an errored
from, including retaining field value and better error codes.

It also adds error recovery for the registration form, and properly
loads the post_login_action context in case of errors.

crates/data-model/src/errors.rs

@@ -1,117 +0,0 @@
-// Copyright 2021 The Matrix.org Foundation C.I.C.
-//
-// Licensed under the Apache License, Version 2.0 (the "License");
-// you may not use this file except in compliance with the License.
-// You may obtain a copy of the License at
-//
-//     http://www.apache.org/licenses/LICENSE-2.0
-//
-// Unless required by applicable law or agreed to in writing, software
-// distributed under the License is distributed on an "AS IS" BASIS,
-// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-// See the License for the specific language governing permissions and
-// limitations under the License.
-
-use std::{collections::HashMap, fmt::Debug, hash::Hash};
-
-use serde::{ser::SerializeMap, Serialize};
-
-pub trait HtmlError: Debug + Send + Sync + 'static {
-    fn html_display(&self) -> String;
-}
-
-pub trait WrapFormError<FieldType> {
-    fn on_form(self) -> ErroredForm<FieldType>;
-    fn on_field(self, field: FieldType) -> ErroredForm<FieldType>;
-}
-
-impl<E, FieldType> WrapFormError<FieldType> for E
-where
-    E: HtmlError,
-{
-    fn on_form(self) -> ErroredForm<FieldType> {
-        let mut f = ErroredForm::new();
-        f.form.push(FormError {
-            error: Box::new(self),
-        });
-        f
-    }
-
-    fn on_field(self, field: FieldType) -> ErroredForm<FieldType> {
-        let mut f = ErroredForm::new();
-        f.fields.push(FieldError {
-            field,
-            error: Box::new(self),
-        });
-        f
-    }
-}
-
-#[derive(Debug)]
-struct FormError {
-    error: Box<dyn HtmlError>,
-}
-
-impl Serialize for FormError {
-    fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error>
-    where
-        S: serde::Serializer,
-    {
-        serializer.serialize_str(&self.error.html_display())
-    }
-}
-
-#[derive(Debug)]
-struct FieldError<FieldType> {
-    field: FieldType,
-    error: Box<dyn HtmlError>,
-}
-
-#[derive(Debug)]
-pub struct ErroredForm<FieldType> {
-    form: Vec<FormError>,
-    fields: Vec<FieldError<FieldType>>,
-}
-
-impl<T> Default for ErroredForm<T> {
-    fn default() -> Self {
-        Self {
-            form: Vec::new(),
-            fields: Vec::new(),
-        }
-    }
-}
-
-impl<T> ErroredForm<T> {
-    #[must_use]
-    pub fn new() -> Self {
-        Self {
-            form: Vec::new(),
-            fields: Vec::new(),
-        }
-    }
-}
-
-impl<FieldType: Copy + Serialize + Hash + Eq> Serialize for ErroredForm<FieldType> {
-    fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error>
-    where
-        S: serde::Serializer,
-    {
-        let mut map = serializer.serialize_map(Some(2))?;
-        let has_errors = !self.form.is_empty() || !self.fields.is_empty();
-        map.serialize_entry("has_errors", &has_errors)?;
-        map.serialize_entry("form_errors", &self.form)?;
-
-        let fields: HashMap<FieldType, Vec<String>> =
-            self.fields.iter().fold(HashMap::new(), |mut map, err| {
-                map.entry(err.field)
-                    .or_default()
-                    .push(err.error.html_display());
-                map
-            });
-
-        map.serialize_entry("fields_errors", &fields)?;
-
-        map.end()
-    }
-}

crates/data-model/src/lib.rs

@@ -22,7 +22,6 @@
     clippy::trait_duplication_in_bounds
 )]
 
-pub mod errors;
 pub(crate) mod oauth2;
 pub(crate) mod tokens;
 pub(crate) mod traits;