ezidam/crates/email/src/lib.rs

151 lines
4.1 KiB
Rust

use lettre::message::header::ContentType;
use lettre::transport::smtp::authentication::Credentials;
use lettre::transport::smtp::response::Response;
use lettre::{AsyncSmtpTransport, AsyncTransport, Message, Tokio1Executor};
use mrml::mjml::Mjml;
use mrml::prelude::parse::Error as MjmlParserError;
use mrml::prelude::render::{Error as MjmlRenderError, Options};
use serde::{Deserialize, Serialize};
use tera::{Context, Tera};
// error
#[derive(thiserror::Error)]
// the rest
#[derive(Debug)]
pub enum Error {
#[error("Template error: {0}")]
Template(#[from] tera::Error),
#[error("Mjml parser error: {0}")]
MjmlParser(#[from] MjmlParserError),
#[error("Mjml render error: {0}")]
MjmlRender(#[from] MjmlRenderError),
#[error("Invalid email address: {0}")]
EmailAddress(#[from] lettre::address::AddressError),
#[error("Invalid email message: {0}")]
EmailMessage(#[from] lettre::error::Error),
#[error("Error when sending email: {0}")]
EmailSend(#[from] lettre::transport::smtp::Error),
#[error("Invalid {0}")]
InvalidConfig(&'static str),
}
const TEMPLATE_EXT: &str = ".mjml.tera";
pub fn render_template<C: Serialize>(
name: &str,
template_dir: &str,
content: C,
) -> Result<String, Error> {
let templates = format!("{template_dir}/**/*{TEMPLATE_EXT}");
// Initialize tera templates
let tera = Tera::new(&templates)?;
// Construct context
let context = Context::from_serialize(content)?;
// Render template
let template_name = format!("{name}{TEMPLATE_EXT}");
Ok(tera.render(&template_name, &context)?)
}
pub fn render_email(mjml: &str) -> Result<String, Error> {
// Parse mjml
let root = Mjml::parse(mjml)?;
// Render to html
let opts = Options::default();
Ok(root.render(&opts)?)
}
#[derive(Debug, Deserialize)]
#[serde(rename_all = "lowercase")]
pub enum Transport {
Unencrypted,
Tls,
StartTls,
}
#[derive(Debug, Deserialize)]
pub struct Config {
pub template_dir: String,
pub from: String,
pub transport: Transport,
pub host: String,
pub port: Option<u16>,
pub username: Option<String>,
pub password: Option<String>,
}
impl Config {
pub fn status(&self) -> Result<String, &'static str> {
match self.transport {
Transport::Unencrypted => match self.port {
Some(port) => Ok(format!("Using \"{}:{port}\" to send emails", self.host)),
None => Err("Port not provided."),
},
Transport::Tls | Transport::StartTls => {
if self.username.is_none() {
return Err("Username not provided.");
}
if self.password.is_none() {
return Err("Password not provided.");
}
Ok(format!("Using \"{}\" to send emails", self.host))
}
}
}
}
fn create_credentials(config: &Config) -> Result<Credentials, Error> {
let username = config
.username
.as_deref()
.ok_or(Error::InvalidConfig("username"))?;
let password = config
.password
.as_deref()
.ok_or(Error::InvalidConfig("password"))?;
Ok(Credentials::from((username, password)))
}
pub async fn send_email(
config: &Config,
user: &str,
email_title: &str,
html: String,
) -> Result<Response, Error> {
let m = Message::builder()
.from(config.from.parse()?)
.to(user.parse()?)
.subject(email_title)
.header(ContentType::TEXT_HTML)
.body(html)?;
type SmtpTransport = AsyncSmtpTransport<Tokio1Executor>;
let mailer = match config.transport {
Transport::Unencrypted => {
let port = config.port.ok_or(Error::InvalidConfig("port"))?;
SmtpTransport::builder_dangerous(&config.host).port(port)
}
Transport::Tls => {
SmtpTransport::relay(&config.host)?.credentials(create_credentials(config)?)
}
Transport::StartTls => {
SmtpTransport::starttls_relay(&config.host)?.credentials(create_credentials(config)?)
}
}
.build();
Ok(mailer.send(m).await?)
}