Python SDK

Send email with Flask

Use Parcel Wing from Flask routes with server-side API key handling.

Install the SDK

The official SDK is published as parcelwing.

Terminal

pip install parcelwing

Route

Create a JSON endpoint that sends a template email and returns structured Parcel Wing errors.

app.py

import os
 
from flask import Flask, jsonify, request
from parcelwing import ParcelWing, ParcelWingError
 
app = Flask(__name__)
parcel_wing = ParcelWing(api_key=os.environ["PARCEL_WING_API_KEY"])
 
@app.post("/send-welcome")
def send_welcome():
    data = request.get_json() or {}
 
    try:
        emails = parcel_wing.emails.send(
            from_="Acme <[email protected]>",
            to=data["email"],
            template_alias="welcome_email",
            template_params={
                "first_name": data.get("first_name") or "friend",
            },
        )
        return jsonify({"id": emails[0]["id"]})
    except ParcelWingError as error:
        return jsonify({
            "code": error.code,
            "request_id": error.request_id,
        }), error.status

Production notes

Keep PARCEL_WING_API_KEY in server-side environment variables.
Validate and rate limit public form endpoints before sending email.
Use templates instead of building repeated HTML in route handlers.