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 1.71 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 all other platforms.
- 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
§Building lettre with OpenSSL
When building lettre with native-tls on a system that makes use of OpenSSL, the following packages will need to be installed in order for the build and the compiled program to run properly.
Distro | Build-time packages | Runtime packages |
---|---|---|
Debian | pkg-config , libssl-dev | libssl3 , ca-certificates |
Alpine Linux | pkgconf , openssl-dev | libssl3 , ca-certificates |
§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 0.3Mime
struct - dkim: Add support for signing email with DKIM
Re-exports§
pub use crate::address::Address;
pub use crate::transport::smtp::AsyncSmtpTransport;
pub use crate::transport::smtp::SmtpTransport;
Modules§
- address
- Email addresses
- error
- Error type for email messages
- message
builder
- Provides a strongly typed way to build emails
- transport
- Transports for sending emails
Structs§
- Async
File Transport file-transport
and (tokio1
orasync-std1
) - Asynchronously writes the content and the envelope information to a file
- Async
Sendmail Transport sendmail-transport
and (tokio1
orasync-std1
) - Asynchronously sends emails using the
sendmail
command - Async
Std1 Executor - Async
Executor
usingasync-std
1.x
- File
Transport file-transport
- Writes the content and the envelope information to a file
- Message
builder
- Email message which can be formatted
- Sendmail
Transport sendmail-transport
- Sends emails using the
sendmail
command - Tokio1
Executor - Async
Executor
usingtokio
1.x
Traits§
- Async
Transport tokio1
orasync-std1
- Async Transport method for emails
- Executor
- Async executor abstraction trait
- Transport
- Blocking Transport method for emails