Go SDK

Send email with Echo

Use Parcel Wing from Echo handlers and request-scoped contexts.

Install the SDK

The official Go SDK is published as github.com/parcelwing/parcelwing-go.

Terminal

go get github.com/parcelwing/parcelwing-go

Echo handler

Create the Parcel Wing client during server startup, then reuse it from trusted server-side handlers.

main.go

package main
 
import (
    "net/http"
    "os"
 
    "github.com/labstack/echo/v4"
    parcelwing "github.com/parcelwing/parcelwing-go"
)
 
func main() {
    client, err := parcelwing.New(os.Getenv("PARCELWING_API_KEY"))
    if err != nil {
        panic(err)
    }
 
    e := echo.New()
    e.POST("/send-welcome", func(c echo.Context) error {
        payload := map[string]string{}
        if err := c.Bind(&payload); err != nil {
            return c.JSON(http.StatusBadRequest, map[string]string{"error": "invalid json"})
        }
 
        emails, err := client.Emails.Send(c.Request().Context(), parcelwing.EmailSendRequest{
            From:          os.Getenv("PARCELWING_FROM_EMAIL"),
            To:            payload["email"],
            TemplateAlias: "welcome",
            TemplateParams: map[string]any{"first_name": payload["first_name"]},
        })
        if err != nil {
            return c.JSON(http.StatusBadGateway, map[string]string{"error": err.Error()})
        }
 
        return c.JSON(http.StatusOK, map[string]any{"id": emails[0].ID})
    })
 
    e.Logger.Fatal(e.Start(":8080"))
}

Production notes

Keep PARCELWING_API_KEY in server-side environment variables.
Use the incoming request context where available so sends can respect request cancellation.
Log structured *parcelwing.Error fields for support and debugging.