send-mail 📧

The send-mail Windows program sends emails using the smtp protocol. Emails are sent using a smtp/smtps server with or without username/password command-line options.

Implemented in c++17 and use vcpkg/cmake for the build-system.

It uses the winpp header-only library from: https://github.com/strinque/winpp.

Features

• use the open-source mailio library to format/send email
• use the open-source openssl library for tls
• check emails validity (src/dst/reply) using std::regex
• can send emails to multiple destinations
• can attach file to emails
• provide a c++ class: SendMail to send email with arguments checked at compile-time
• implement a program: send-mail.exe which use the SendMail to send emails

Usage

send-email.exe --src-name \"src name\" \
               --src-email src@xxx.com \
               --dst-name \"dstName A;dstName B;\" \
               --dst-email \"dstA@yyy.com; dstB@yyy.com;" \
               --smtp-server xxx.smtp.com \
               --smtp-username user \
               --smtp-password password \
               --smtp-tls \
               --email-title "Title" \
               --email-content "Content of the mail\r\nWith newlines" \
               --email-file "file.7z"

The following arguments are mandatory for send-email.exe:

• --smtp-server
• --src-email
• --dst-email
• --email-title
• --email-content

SendMail

The SendMail class contains all the logic for formatting/sending the emails.
The interface is simple, all arguments are given to the Email class constructor in any order.
The types of these arguments will be checked during compile-time thanks to templates.

The following arguments are mandatory for SendMail:

• option::smtp_server: std::string
• option::src_email: std::string
• option::dst_email: std::string
• option::email_title: std::string
• option::email_content: std::string

These arguments have specific types:

• option::email_file: std::filesystem::path
• option::smtp_tls: bool

// construct email
Email mail({
  option::smtp_server("server.smtp.fr"),
  option::src_email("src@email.fr"),
  option::dst_email("dst@email.fr"),
  option::email_title("email title"),
  option::email_content("email content\r\nwith multiple lines")
  });

// send email
std::string mailio_error;
if (!mail.send(mailio_error))
  throw std::runtime_error(mailio_error);

Requirements

This project uses vcpkg, a free C/C++ package manager for acquiring and managing libraries to build all the required libraries.
It also needs the installation of the winpp, a private header-only library, inside vcpkg.

Install vcpkg

The install procedure can be found in: https://vcpkg.io/en/getting-started.html.
The following procedure installs vcpkg and integrates it in Visual Studio.

Open PowerShell:

cd c:\
git clone https://github.com/Microsoft/vcpkg.git
cd vcpkg
.\bootstrap-vcpkg.bat
.\vcpkg.exe integrate install

Create a x64-windows-static-md triplet file used to build the program in shared-mode for Windows CRT libraries but static-mode for third-party libraries:

$VCPKG_DIR = Get-Content "$Env:LocalAppData/vcpkg/vcpkg.path.txt" -Raw 

Set-Content "$VCPKG_DIR/triplets/community/x64-windows-static-md.cmake" 'set(VCPKG_TARGET_ARCHITECTURE x64)
set(VCPKG_CRT_LINKAGE dynamic)
set(VCPKG_LIBRARY_LINKAGE static)
set(VCPKG_BUILD_TYPE release)'

Install winpp ports-files

Copy the vcpkg ports files from winpp header-only library repository to the vcpkg directory.

$VCPKG_DIR = Get-Content "$Env:LocalAppData/vcpkg/vcpkg.path.txt" -Raw 

mkdir $VCPKG_DIR/ports/winpp
Invoke-WebRequest -Uri "https://raw.githubusercontent.com/strinque/winpp/master/vcpkg/ports/winpp/portfile.cmake" -OutFile "$VCPKG_DIR/ports/winpp/portfile.cmake"
Invoke-WebRequest -Uri "https://raw.githubusercontent.com/strinque/winpp/master/vcpkg/ports/winpp/vcpkg.json" -OutFile "$VCPKG_DIR/ports/winpp/vcpkg.json"

Build

Build using cmake

To build the program with vcpkg and cmake, follow these steps:

$VCPKG_DIR = Get-Content "$Env:LocalAppData/vcpkg/vcpkg.path.txt" -Raw 

git clone https://github.com/strinque/send-mail
cd send-mail
mkdir build; cd build
cmake -DCMAKE_BUILD_TYPE="MinSizeRel" `
      -DVCPKG_TARGET_TRIPLET="x64-windows-static-md" `
      -DCMAKE_TOOLCHAIN_FILE="$VCPKG_DIR/scripts/buildsystems/vcpkg.cmake" `
      ../
cmake --build . --config MinSizeRel

The program executable should be compiled in: send-mail\build\src\MinSizeRel\send-mail.exe.

Build with Visual Studio

Microsoft Visual Studio can automatically install required vcpkg libraries and build the program thanks to the pre-configured files:

• CMakeSettings.json: debug and release settings
• vcpkg.json: libraries dependencies

The following steps needs to be executed in order to build/debug the program:

File => Open => Folder...
  Choose send-mail root directory
Solution Explorer => Switch between solutions and available views => CMake Targets View
Select x64-release or x64-debug
Select the src\send-mail.exe (not bin\send-mail.exe)

To add command-line arguments for debugging the program:

Solution Explorer => Project => (executable) => Debug and Launch Settings => src\program.exe

  "args": [
    "--src-email src@xxx.com",
    "--dst-email dst@yyy.com",
    "--smtp-server xxx.smtp.com",
    "--smtp-username user",
    "--smtp-password password",
    "--smtp-tls",
    "--email-title \"Title\"",
    "--email-content \"Content of the mail\"",
    "--email-file \"file.7z\""
  ]