# go-mail - Easy to use, yet comprehensive library for sending mails with Go [![GoDoc](https://godoc.org/github.com/wneessen/go-mail?status.svg)](https://pkg.go.dev/github.com/wneessen/go-mail) [![codecov](https://codecov.io/gh/wneessen/go-mail/branch/main/graph/badge.svg?token=37KWJV03MR)](https://codecov.io/gh/wneessen/go-mail) [![Go Report Card](https://goreportcard.com/badge/github.com/wneessen/go-mail)](https://goreportcard.com/report/github.com/wneessen/go-mail) [![Mentioned in Awesome Go](https://awesome.re/mentioned-badge-flat.svg)](https://github.com/avelino/awesome-go) [![#go-mail on Discord](https://img.shields.io/badge/Discord-%23gomail-blue.svg)](https://discord.gg/zSUeBrsFPB) [![REUSE status](https://api.reuse.software/badge/github.com/wneessen/go-mail)](https://api.reuse.software/info/github.com/wneessen/go-mail)
The main idea of this library was to provide a simple interface to sending mails for my [JS-Mailer](https://github.com/wneessen/js-mailer) project. It quickly evolved into a full-fledged mail library. go-mail follows idiomatic Go style and best practice. It's only dependency is the Go Standard Library. It combines a lot of functionality from the standard library to give easy and convenient access to mail and SMTP related tasks. Parts of this library (especially some parts of [msgwriter.go](msgwriter.go)) have been forked/ported from the [go-mail/mail](https://github.com/go-mail/mail) respectively [go-gomail/gomail](https://github.com/go-gomail/gomail) which both seems to not be maintained anymore. The smtp package of go-mail is forked from the original Go stdlib's `net/smtp` and then extended by the go-mail team. ## Features Some of the features of this library: * [X] Only Standard Library dependant * [X] Modern, idiomatic Go * [X] Sane and secure defaults * [X] Explicit SSL/TLS support * [X] Implicit StartTLS support with different policies * [X] Makes use of contexts for a better control flow and timeout/cancelation handling * [X] SMTP Auth support (LOGIN, PLAIN, CRAM-MD) * [X] RFC5322 compliant mail address validation * [X] Support for common mail header field generation (Message-ID, Date, Bulk-Precedence, Priority, etc.) * [X] Reusing the same SMTP connection to send multiple mails * [X] Support for attachments and inline embeds (from file system, `io.Reader` or `embed.FS`) * [X] Support for different encodings * [X] Middleware support for 3rd-party libraries to alter mail messages * [X] Support sending mails via a local sendmail command * [X] Support for requestng MDNs (RFC 8098) and DSNs (RFC 1891) * [X] DKIM signature support via [go-mail-middlware](https://github.com/wneessen/go-mail-middleware) * [X] Message object satisfies `io.WriteTo` and `io.Reader` interfaces * [X] Support for Go's `html/template` and `text/template` (as message body, alternative part or attachment/emebed) * [X] Output to file support which allows storing mail messages as e. g. `.eml` files to disk to open them in a MUA * [X] Debug logging of SMTP traffic * [X] Custom error types for delivery errors go-mail works like a programatic email client and provides lots of methods and functionalities you would consider standard in a MUA. ## Documentation We aim for good GoDoc documenation in our library which gives you a full API reference. We also provide a more in-depth documentation website at [go-mail.dev](https://go-mail.dev) ## Support We have a support and general discussion channel on the Gophers Discord server. Find us at: [#go-mail](https://discord.gg/zSUeBrsFPB) ## Middleware The goal of go-mail is to keep it free from 3rd party dependencies and only focus on things a mail library should fulfill. Yet, since version v0.2.8 we've added support for middleware on the `Msg` object, allowing 3rd parties to alter a given mail message to their needs without relying on `go-mail` to support their specific need. To get our users started with message middleware, we've created a collection of useful middlewares. It can be found in a seperate repository: [go-mail-middlware](https://github.com/wneessen/go-mail-middleware). ## Examples We provide example code in both our GoDocs as well as on our official Website (see [Documentation](#documentation)). For a quick start into go-mail check out our [Getting started](https://go-mail.dev/getting-started/introduction/) guide. ## Authors/Contributors go-mail was initially authored and developed by [Winni Neessen](https://github.com/wneessen/). Big thanks to the following people, for contributing to the go-mail project (either in form of code or by reviewing code, writing documenation or helping to translate the website): * [Dhia Gharsallaoui](https://github.com/dhia-gharsallaoui) * [inliquid](https://github.com/inliquid) * [iwittkau](https://github.com/iwittkau) * [James Elliott](https://github.com/james-d-elliott) * [Maria Letta](https://github.com/MariaLetta) (designed the go-mail logo)