mail-builder

mail-builder is a flexible e-mail builder library written in Rust. It includes the following features:

Generates e-mail messages conforming to the Internet Message Format standard (RFC 5322).
Full MIME support (RFC 2045 - 2049) with automatic selection of the most optimal encoding for each message body part.
Fast Base64 encoding based on Chromium's decoder (the fastest non-SIMD encoder).
Minimal dependencies.

Please note that this library does not support sending or parsing e-mail messages as these functionalities are provided by the crates mail-send and mail-parser.

Usage Example

Build a simple e-mail message with a text body and one attachment:

```rust // Build a simple text message with a single attachment let eml = MessageBuilder::new() .from(("John Doe", "john@doe.com")) .to("jane@doe.com") .subject("Hello, world!") .textbody("Message contents go here.") .binaryattachment("image/png", "image.png", [1, 2, 3, 4].asref()) .writeto_string() .unwrap();

// Print raw message
println!("{}", eml);

```

More complex messages with grouped addresses, inline parts and multipart/alternative sections can also be easily built:

```rust // Build a multipart message with text and HTML bodies, // inline parts and attachments. MessageBuilder::new() .from(("John Doe", "john@doe.com"))

    // To recipients
    .to(vec![
        ("Antoine de Saint-Exupéry", "antoine@exupery.com"),
        ("안녕하세요 세계", "test@test.com"),
        ("Xin chào", "addr@addr.com"),
    ])

    // BCC recipients using grouped addresses
    .bcc(vec![
        (
            "My Group",
            vec![
                ("ASCII name", "addr1@addr7.com"),
                ("ハロー・ワールド", "addr2@addr6.com"),
                ("áéíóú", "addr3@addr5.com"),
                ("Γειά σου Κόσμε", "addr4@addr4.com"),
            ],
        ),
        (
            "Another Group",
            vec![
                ("שלום עולם", "addr5@addr3.com"),
                ("ñandú come ñoquis", "addr6@addr2.com"),
                ("Recipient", "addr7@addr1.com"),
            ],
        ),
    ])

    // Set RFC and custom headers
    .subject("Testing multipart messages") 
    .in_reply_to(vec!["message-id-1", "message-id-2"])
    .header("List-Archive", URL::new("http://example.com/archive"))

    // Set HTML and plain text bodies
    .text_body("This is the text body!\n") 
    .html_body("<p>HTML body with <img src=\"cid:my-image\"/>!</p>") 

    // Include an embedded image as an inline part
    .binary_inline("image/png", "cid:my-image", [0, 1, 2, 3, 4, 5].as_ref())
    .text_attachment("text/plain", "my fíle.txt", "Attachment contents go here.") 

    // Add text and binary attachments
    .binary_attachment(
        "text/plain",
        "ハロー・ワールド",
        b"Binary contents go here.".as_ref(),
    )

    // Write the message to a file
    .write_to(File::create("message.eml").unwrap())
    .unwrap();

```

Nested MIME body structures can be created using the body method:

```rust // Build a nested multipart message MessageBuilder::new() .from(Address::newaddress("John Doe".into(), "john@doe.com")) .to(Address::newaddress("Jane Doe".into(), "jane@doe.com")) .subject("Nested multipart message")

    // Define the nested MIME body structure
    .body(MimePart::new_multipart(
        "multipart/mixed",
        vec![
            MimePart::new_text("Part A contents go here...").inline(),
            MimePart::new_multipart(
                "multipart/mixed",
                vec![
                    MimePart::new_multipart(
                        "multipart/alternative",
                        vec![
                            MimePart::new_multipart(
                                "multipart/mixed",
                                vec![
                                    MimePart::new_text("Part B contents go here...").inline(),
                                    MimePart::new_binary(
                                        "image/jpeg",
                                        "Part C contents go here...".as_bytes(),
                                    )
                                    .inline(),
                                    MimePart::new_text("Part D contents go here...").inline(),
                                ],
                            ),
                            MimePart::new_multipart(
                                "multipart/related",
                                vec![
                                    MimePart::new_html("Part E contents go here...").inline(),
                                    MimePart::new_binary(
                                        "image/jpeg",
                                        "Part F contents go here...".as_bytes(),
                                    ),
                                ],
                            ),
                        ],
                    ),
                    MimePart::new_binary("image/jpeg", "Part G contents go here...".as_bytes())
                        .attachment("image_G.jpg"),
                    MimePart::new_binary(
                        "application/x-excel",
                        "Part H contents go here...".as_bytes(),
                    ),
                    MimePart::new_binary(
                        "x-message/rfc822",
                        "Part J contents go here...".as_bytes(),
                    ),
                ],
            ),
            MimePart::new_text("Part K contents go here...").inline(),
        ],
    ))

    // Write the message to a file
    .write_to(File::create("nested-message.eml").unwrap())
    .unwrap();

```

Testing

To run the testsuite:

bash $ cargo test --all-features

or, to run the testsuite with MIRI:

bash $ cargo +nightly miri test --all-features

License

Licensed under either of

Apache License, Version 2.0 (LICENSE-APACHE or http://www.apache.org/licenses/LICENSE-2.0)
MIT license (LICENSE-MIT or http://opensource.org/licenses/MIT)

at your option.

Copyright

See [COPYING] for the license.