Simple HTTP API to sh's sendmail

.gitignore

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+bin

Makefile

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+build:
+	env CGO_ENABLED=0 GOOS=linux GOARCH=amd64 go build -o ./bin/sendmail-http
+clean:
+	rm ./bin/sendmail-http

README.md

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+Simple http to sendmail

main.go

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+package main
+
+import (
+	"fmt"
+	"net/http"
+	"os"
+	"os/exec"
+
+	"github.com/labstack/echo"
+	"github.com/labstack/echo/middleware"
+)
+
+type mailReq struct {
+	From    string `query:"from"`
+	To      string `query:"to"`
+	Subject string `query:"subject"`
+	Body    string `query:"body"`
+}
+
+func callSendmail(req mailReq) error {
+	line := fmt.Sprintf("From: %s\\nTo: %s\\nSubject: %s\\n\\n%s",
+		req.From, req.To, req.Subject, req.Body)
+	c1 := exec.Command("echo", "-e", line)
+	c2 := exec.Command("sendmail", req.To)
+	c2.Stdin, _ = c1.StdoutPipe()
+	c2.Stdout = os.Stdout
+	_ = c2.Start()
+	_ = c1.Run()
+	_ = c2.Wait()
+	return nil
+}
+
+func main() {
+
+	var serverAddr = os.Getenv("SERVER_ADDR")
+	if len(serverAddr) == 0 {
+		panic("Server address must not be empty")
+	}
+
+	e := echo.New()
+	e.Use(middleware.Recover())
+
+	api_group := e.Group("/api")
+
+	api_group.GET("/sendmail", func(c echo.Context) error {
+
+		req := mailReq{}
+		if err := c.Bind(&req); err != nil {
+			return c.JSON(http.StatusBadRequest, map[string]string{
+				"status": "error",
+				"desc":   err.Error(),
+			})
+		}
+		callSendmail(req)
+		return c.JSON(http.StatusOK, map[string]string{
+			"status": "ok",
+		})
+	})
+
+	err := e.Start(serverAddr)
+	if err != nil {
+		panic(err.Error())
+	}
+
+}