Crate lettre

source ·
Expand description

Lettre is an email library that allows creating and sending messages. It provides:

  • An easy to use email builder
  • Pluggable email transports
  • Unicode support
  • Secure defaults
  • Async support

Lettre requires Rust 1.60 or newer.

Features

This section lists each lettre feature and briefly explains it. More info about each module can be found in the corresponding module page.

Features with 📫 near them are enabled by default.

Typed message builder

Strongly typed message builder

  • builder 📫: Enable the Message builder
  • hostname 📫: Try to use the actual system hostname in the Message-ID header

SMTP transport

Send emails using SMTP

  • smtp-transport 📫: Enable the SMTP transport
  • pool 📫: Connection pool for SMTP transport
  • hostname 📫: Try to use the actual system hostname for the SMTP CLIENTID
SMTP over TLS via the native-tls crate

Secure SMTP connections using TLS from the native-tls crate

Uses schannel on Windows, Security-Framework on macOS, and OpenSSL on Linux.

  • native-tls 📫: TLS support for the synchronous version of the API
  • tokio1-native-tls: TLS support for the tokio1 async version of the API

NOTE: native-tls isn’t supported with async-std

SMTP over TLS via the boring crate (Boring TLS)

Secure SMTP connections using TLS from the boring-tls crate

  • boring-tls: TLS support for the synchronous version of the API
  • tokio1-boring-tls: TLS support for the tokio1 async version of the API

NOTE: boring-tls isn’t supported with async-std

SMTP over TLS via the rustls crate

Secure SMTP connections using TLS from the rustls-tls crate

Rustls uses ring as the cryptography implementation. As a result, not all Rust’s targets are supported.

  • rustls-tls: TLS support for the synchronous version of the API
  • tokio1-rustls-tls: TLS support for the tokio1 async version of the API
  • async-std1-rustls-tls: TLS support for the async-std1 async version of the API

Sendmail transport

Send emails using the sendmail command

  • sendmail-transport: Enable the sendmail transport

File transport

Save emails as an .eml file

  • file-transport: Enable the file transport (saves emails into an .eml file)
  • file-transport-envelope: Allow writing the envelope into a JSON file (additionally saves envelopes into a .json file)

Async execution runtimes

Use tokio or async-std as an async execution runtime for sending emails

The correct runtime version must be chosen in order for lettre to work correctly. For example, when sending emails from a Tokio 1.x context, the Tokio 1.x executor (Tokio1Executor) must be used. Using a different version (for example Tokio 0.2.x), or async-std, would result in a runtime panic.

  • tokio1: Allow to asynchronously send emails using Tokio 1.x
  • async-std1: Allow to asynchronously send emails using async-std 1.x

NOTE: native-tls isn’t supported with async-std

Misc features

Additional features

  • serde: Serialization/Deserialization of entities
  • tracing: Logging using the tracing crate
  • mime03: Allow creating a ContentType from an existing mime 0.3 Mime struct
  • dkim: Add support for signing email with DKIM

Modules

address
Email addresses
error
Error type for email messages
messagebuilder
Provides a strongly typed way to build emails
transport
Transports for sending emails

Structs

Address
Represents an email address with a user and a domain name.
AsyncFileTransportfile-transport and (tokio1 or async-std1)
Asynchronously writes the content and the envelope information to a file
AsyncSendmailTransportsendmail-transport and (tokio1 or async-std1)
Asynchronously sends emails using the sendmail command
AsyncSmtpTransportsmtp-transport and (tokio1 or async-std1)
Asynchronously sends emails using the SMTP protocol
AsyncStd1Executorasync-std1
Async Executor using async-std 1.x
FileTransportfile-transport
Writes the content and the envelope information to a file
Messagebuilder
Email message which can be formatted
SendmailTransportsendmail-transport
Sends emails using the sendmail command
SmtpTransportsmtp-transport
Sends emails using the SMTP protocol
Tokio1Executortokio1
Async Executor using tokio 1.x

Traits

AsyncTransporttokio1 or async-std1
Async Transport method for emails
Executortokio1 or async-std1
Async executor abstraction trait
Transport
Blocking Transport method for emails