We use optional, privacy-safe analytics to understand which pages help visitors. Nothing optional runs until you choose. Privacy policy

Skip to content
AvailableDirect HTTP API

Send messages from Python with the SendiMessage API

Python has an official SendiMessage SDK on PyPI: pip install sendimessage. It is pure standard library — nothing else to install — and covers the whole public API, from sending and media upload to contacts, lines, conversations, and webhook management.

Wire it into a Django signal, a Celery task, a Flask route, or a cron script — the send call is the same three lines everywhere, and ApiError surfaces failures in your logs instead of passing silently.

Request This SetupBook an Integration Review

What this integration enables

Transactional notifications
Order confirmations, payment receipts, and status changes triggered by your backend.
Appointment reminders
Scheduled jobs that message customers before a booking.
Operational alerts
Delivery windows, service updates, and internal notifications.
Two-way conversations
Incoming replies arrive on your webhook endpoint for routing to support or sales.

Architecture

How it fits together: Your application event, then Python server code, then SendiMessage API, then Managed messaging line, then Webhook events.
  1. Your application eventAn order ships, a booking nears, a ticket updates
  2. Python server codeBuilds the request with credentials from the environment
  3. SendiMessage APIPOST /send-message returns the queued message
  4. Managed messaging lineSMS, or iMessage on supported lines and destinations
  5. Webhook eventsDelivery status and incoming replies post back to your endpoint

Example request

Python
# pip install sendimessage
import os
from sendimessage import ApiError, Client
client = Client(
api_key=os.environ["SENDIMESSAGE_KEY"],
api_secret=os.environ["SENDIMESSAGE_SECRET"],
)
try:
msg = client.send_message(number="+15555550123", content="Hello from SendiMessage")
print(msg["message_handle"], msg["status"]) # "4e828182-…" "QUEUED"
except ApiError as err:
print(f"SendiMessage error {err.status}: {err.body}")
raise

Delivery events and incoming replies

Delivery status and incoming replies arrive as signed webhook events. Verify the signature, then correlate events with your own records via the message_handle returned when you sent.

webhook event
// "outbound" event → your python endpoint
// Verify the SendiMessage-Signature header (t={timestamp},v1=HMAC-SHA256 of
// "{timestamp}.{raw body}", keyed with your webhook secret), then use
// GET /v2/messages/{message_handle} for authoritative state and match it to
// your contact_id in python.

Limitations and honest notes

  • iMessage delivery is available on supported messaging lines and destinations. Recipients without iMessage receive SMS when fallback is configured — never assume universal iMessage availability.
  • Messages are accepted asynchronously — the API returns status QUEUED and final status arrives via webhook or the message endpoints.
  • Official SDKs are published for JavaScript/TypeScript (npm: sendimessage), Python (PyPI: sendimessage), PHP (Composer: sendimessage/sdk), and Go (github.com/sendimessage/sendimessage-go). Every SDK is dependency-free and covers the full public API surface.

Security considerations

  • Load the API key pair from the environment — never commit it or embed it in client-side code.
  • Verify webhook signatures before processing events.
  • Log message handles, not message bodies, in shared logs.

Frequently asked questions

Is there an official Python SDK for SendiMessage?
Yes — install it with `pip install sendimessage`. The SDK is dependency-free, covers the full public API (messages, media, lookup, contacts, lines, conversations, webhooks), and ships a webhook signature verification helper.
What does the API return when I send a message?
The API accepts messages asynchronously and responds with status "QUEUED" plus a message_handle and the line_handle it will send from. Track final delivery via GET /status, the message history endpoints, or webhook events.
Can I send iMessage from Python?
SendiMessage delivers over iMessage where the destination supports it on your managed line, and falls back to SMS when fallback is configured. iMessage is never guaranteed for every recipient.

Ready to connect Python?

Request a messaging line and a SendiMessage integration specialist will review your Python workflow and guide the setup.