Call Blasting

<Response>
    <Speak>
        Hello, this is a reminder that your appointment is tomorrow at 10 AM.
    </Speak>
    <Hangup/>
</Response>

<Response>
    <Play>https://cdn.example.com/reminder.mp3</Play>
    <Hangup/>
</Response>

import asyncio
from pathlib import Path

import httpx
from unpod import AsyncClient
from unpod.telephony import TelephonyAPIError

FROM = "+919000000001"  # your Unpod number
ANSWER_URL = "https://cdn.example.com/blast.xml"
STATUS_URL = "https://your-app.example.com/blast-status"  # step 3, optional
CAMPAIGN = "reminder-nov"
PACE = 1.0  # seconds between creates: Unpod accepts 60 a minute per org


async def dial(calls, to: str) -> str | None:
    """None once Unpod accepts the call, else why it wasn't."""
    for attempt in range(6):
        try:
            await calls.create(
                FROM,
                to,
                answer_url=ANSWER_URL,
                answer_method="GET",
                status_callback_url=STATUS_URL,
                metadata={"campaign": CAMPAIGN, "to": to},  # back on events
                idempotency_key=f"{CAMPAIGN}:{to}",  # a retry won't dial twice
            )
            return None
        except TelephonyAPIError as e:
            if e.status_code != 429:  # a bad number doesn't stop the batch
                return f"{e.status_code} {e.code}: {e.message}"
        except httpx.HTTPError:
            pass  # network error: the same idempotency key makes a retry safe
        await asyncio.sleep(min(2**attempt, 30))  # 429 or network error: back off
    return "gave up after retries"


async def main() -> None:
    r = httpx.get(ANSWER_URL, timeout=3)  # the file Unpod will fetch
    r.raise_for_status()  # also fails on a redirect, which Unpod won't follow
    assert "<Response" in r.text, "blast.xml is empty or not XML"

    lines = Path("numbers.txt").read_text().splitlines()
    numbers = list(dict.fromkeys(n.strip() for n in lines if n.strip()))  # no dupes
    failed: dict[str, str] = {}
    async with AsyncClient() as client:
        calls = client.telephony.calls
        for to in numbers:
            reason = await dial(calls, to)
            if reason:
                failed[to] = reason
            await asyncio.sleep(PACE)
    print(f"accepted {len(numbers) - len(failed)} of {len(numbers)}")
    for to, reason in failed.items():
        print("failed", to, reason)


asyncio.run(main())

# prints each number with the HTTP status: 202 accepted, anything else failed
while read -r to || [ -n "$to" ]; do
  to=${to%$'\r'}; [ -z "$to" ] && continue
  curl -s -o /dev/null -w "$to %{http_code}\n" \
    -X POST "https://unpod.ai/api/v2/platform/sbc/v1/calls" \
    -H "Authorization: Token $UNPOD_PLATFORM_TOKEN" \
    -H "Org-Handle: $UNPOD_ORG_HANDLE" \
    -H "Idempotency-Key: reminder-nov:$to" -H "Content-Type: application/json" \
    -d '{"from": "+919000000001", "to": "'"$to"'",
         "answer_url": "https://cdn.example.com/blast.xml", "answer_method": "GET",
         "status_callback_url": "https://your-app.example.com/blast-status",
         "metadata": {"campaign": "reminder-nov", "to": "'"$to"'"}}'
  sleep 1  # Unpod accepts 60 creates a minute per org
done < numbers.txt