WIP: email sending crate

crates/email/Cargo.toml

@@ -0,0 +1,18 @@
+[package]
+name = "mas-email"
+version = "0.1.0"
+authors = ["Quentin Gliech <quenting@element.io>"]
+edition = "2021"
+license = "Apache-2.0"
+
+[dependencies]
+tokio = { version = "1.15.0", features = ["macros"] }
+
+mas-templates = { path = "../templates" }
+anyhow = "1.0.52"
+async-trait = "0.1.52"
+
+[dependencies.lettre]
+version = "0.10.0-rc.4"
+default-features = false
+features = ["tokio1-rustls-tls", "hostname", "builder", "tracing", "pool"]

crates/email/src/lib.rs

@@ -0,0 +1,78 @@
+// Copyright 2022 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 lettre::{
+    message::{Mailbox, MessageBuilder, MultiPart},
+    AsyncTransport, Message,
+};
+use mas_templates::{EmailVerificationContext, Templates};
+
+pub struct Mailer {
+    templates: Templates,
+    from: Mailbox,
+    reply_to: Mailbox,
+}
+
+impl Mailer {
+    pub fn new<T>(templates: &Templates, from: Mailbox, reply_to: Mailbox) -> Self {
+        Self {
+            templates: templates.clone(),
+            from,
+            reply_to,
+        }
+    }
+
+    fn base_message(&self) -> MessageBuilder {
+        Message::builder()
+            .from(self.from.clone())
+            .reply_to(self.reply_to.clone())
+    }
+
+    async fn prepare_verification_email(
+        &self,
+        to: Mailbox,
+        context: &EmailVerificationContext,
+    ) -> anyhow::Result<Message> {
+        let plain = self
+            .templates
+            .render_email_verification_txt(context)
+            .await?;
+
+        let html = self
+            .templates
+            .render_email_verification_html(context)
+            .await?;
+
+        let multipart = MultiPart::alternative_plain_html(plain, html);
+
+        let message = self.base_message().to(to).multipart(multipart)?;
+
+        Ok(message)
+    }
+
+    pub async fn send_verification_email<T>(
+        &self,
+        transport: &T,
+        to: Mailbox,
+        context: &EmailVerificationContext,
+    ) -> anyhow::Result<()>
+    where
+        T: AsyncTransport + Send + Sync,
+        T::Error: std::error::Error + Send + Sync + 'static,
+    {
+        let message = self.prepare_verification_email(to, context).await?;
+        transport.send(message).await?;
+        Ok(())
+    }
+}

crates/templates/src/context.rs

@@ -17,7 +17,7 @@
 #![allow(clippy::trait_duplication_in_bounds)]
 
 use mas_data_model::{
-    errors::ErroredForm, AuthorizationGrant, BrowserSession, StorageBackend, UserEmail,
+    errors::ErroredForm, AuthorizationGrant, BrowserSession, StorageBackend, User, UserEmail,
 };
 use oauth2_types::errors::OAuth2Error;
 use serde::{ser::SerializeStruct, Serialize};
@@ -76,6 +76,15 @@ pub trait TemplateContext: Serialize {
         Self: Sized;
 }
 
+impl TemplateContext for () {
+    fn sample() -> Vec<Self>
+    where
+        Self: Sized,
+    {
+        Vec::new()
+    }
+}
+
 /// Context with a CSRF token in it
 #[derive(Serialize)]
 pub struct WithCsrf<T> {
@@ -440,6 +449,40 @@ impl<T: StorageBackend> TemplateContext for AccountEmailsContext<T> {
     }
 }
 
+/// Context used by the `emails/verification.{txt,html}` templates
+#[derive(Serialize)]
+pub struct EmailVerificationContext {
+    user: User<()>,
+    verification_link: Url,
+}
+
+impl EmailVerificationContext {
+    #[must_use]
+    pub fn new(user: User<()>, verification_link: Url) -> Self {
+        Self {
+            user,
+            verification_link,
+        }
+    }
+}
+
+impl TemplateContext for EmailVerificationContext {
+    fn sample() -> Vec<Self>
+    where
+        Self: Sized,
+    {
+        User::samples()
+            .into_iter()
+            .map(|u| {
+                Self::new(
+                    u,
+                    Url::parse("https://example.com/emails/verify?code=2134").unwrap(),
+                )
+            })
+            .collect()
+    }
+}
+
 /// Context used by the `form_post.html` template
 #[derive(Serialize)]
 pub struct FormPostContext<T> {

crates/templates/src/lib.rs

@@ -48,10 +48,10 @@ mod functions;
 mod macros;
 
 pub use self::context::{
-    AccountContext, AccountEmailsContext, EmptyContext, ErrorContext, FormPostContext,
-    IndexContext, LoginContext, LoginFormField, PostAuthContext, ReauthContext, ReauthFormField,
-    RegisterContext, RegisterFormField, TemplateContext, WithCsrf, WithOptionalSession,
-    WithSession,
+    AccountContext, AccountEmailsContext, EmailVerificationContext, EmptyContext, ErrorContext,
+    FormPostContext, IndexContext, LoginContext, LoginFormField, PostAuthContext, ReauthContext,
+    ReauthFormField, RegisterContext, RegisterFormField, TemplateContext, WithCsrf,
+    WithOptionalSession, WithSession,
 };
 
 /// Wrapper around [`tera::Tera`] helping rendering the various templates
@@ -312,6 +312,12 @@ register_templates! {
 
     /// Render the HTML error page
     pub fn render_error(ErrorContext) { "pages/error.html" }
+
+    /// Render the email verification email (plain text variant)
+    pub fn render_email_verification_txt(EmailVerificationContext) { "emails/verification.txt" }
+
+    /// Render the email verification email (plain text variant)
+    pub fn render_email_verification_html(EmailVerificationContext) { "emails/verification.html" }
 }
 
 impl Templates {
@@ -323,9 +329,12 @@ impl Templates {
         check::render_index(self).await?;
         check::render_account_index(self).await?;
         check::render_account_password(self).await?;
+        check::render_account_emails::<()>(self).await?;
         check::render_reauth(self).await?;
         check::render_form_post::<EmptyContext>(self).await?;
         check::render_error(self).await?;
+        check::render_email_verification_txt(self).await?;
+        check::render_email_verification_html(self).await?;
         Ok(())
     }
 }

crates/templates/src/res/emails/verification.html

@@ -0,0 +1,23 @@
+{#
+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.
+#}
+
+Hi <b>{{ user.username }}</b>,<br />
+<br />
+click this link to verify your account:<br />
+<br />
+<a href="{{ verification_link }}">{{ verification_link }}</a><br />
+<br />
+kthxbye

crates/templates/src/res/emails/verification.txt

@@ -0,0 +1,23 @@
+{#
+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.
+#}
+
+Hi {{ user.username }},
+
+click this link to verify your account:
+
+<{{ verification_link }}>
+
+kthxbye