Mail a PDF invoice from code

umask 077
mkdir -p ~/.config/pony
pbpaste > ~/.config/pony/api-key          # or write it from your secret manager
printf 'Authorization: Bearer %s\n' "$(cat ~/.config/pony/api-key)" > ~/.config/pony/auth-header
export PONY_API_BASE="https://www.mailbypony.com/api/v1"
export PONY_API_KEY_FILE=~/.config/pony/api-key PONY_AUTH_HEADER=~/.config/pony/auth-header

api() {  # api METHOD PATH [JSON_FILE [IDEMPOTENCY_KEY]]
  if [ $# -ge 4 ]; then
    curl --fail-with-body -sS -X "$1" -H @"$PONY_AUTH_HEADER" -H 'Content-Type: application/json' \
      -H "Idempotency-Key: $4" --data-binary "@$3" "$PONY_API_BASE$2"
  elif [ $# -eq 3 ]; then
    curl --fail-with-body -sS -X "$1" -H @"$PONY_AUTH_HEADER" -H 'Content-Type: application/json' \
      --data-binary "@$3" "$PONY_API_BASE$2"
  else
    curl --fail-with-body -sS -X "$1" -H @"$PONY_AUTH_HEADER" "$PONY_API_BASE$2"
  fi
}
curl -sS "$PONY_API_BASE/catalog" | jq '.prepaid'
api GET /identity | jq '{client_id, scopes}'

api POST /wallet/topups topup.json "topup-$(date +%Y%m%d)-1" | jq '{topup_id, status, checkout_url}'
api GET /wallet | jq '{available_minor, status}'

api POST /drafts draft.json invoice-1042:draft > draft-result.json
DRAFT_ID="$(jq -er .draft_id draft-result.json)"

jq -n --argjson version "$(jq .version draft-result.json)" --rawfile pdf <(base64 < invoice-1042.pdf | tr -d '\n') \
  '{version:$version,kind:"pdf",name:"invoice-1042.pdf",content_base64:$pdf,content_policy_acknowledged:true}' > upload.json
api POST "/drafts/$DRAFT_ID/attachments" upload.json invoice-1042:pdf > upload-result.json
VERSION="$(jq -er .version upload-result.json)"   # the upload advances the version

echo "{\"version\":$VERSION}" > proof.json
api POST "/drafts/$DRAFT_ID/proofs" proof.json invoice-1042:proof > proof-result.json
jq '{proof_id, status, errors, review_url}' proof-result.json

jq -n --arg d "$DRAFT_ID" --argjson v "$VERSION" --arg p "$(jq -er .proof_id proof-result.json)" \
  '{draft_id:$d,version:$v,proof_id:$p,client_reference:"invoice-1042"}' > quote.json
api POST /send-quotes quote.json invoice-1042:quote > quote-result.json
jq '{total_minor, tax_minor, expires_at}' quote-result.json

jq '{send_intent_id,quote_id,proof_id,expected_total_minor:.total_minor,currency}' quote-result.json > send.json
api POST /orders send.json invoice-1042:send | jq '{order_id, status, debited_minor}'

api POST /webhooks webhook.json | jq '{id, secret}'
api POST "/webhooks/$WEBHOOK_ID/test" | jq .            # sends a signed "ping"
api GET "/webhooks/$WEBHOOK_ID/deliveries" | jq '.items[0]'

import base64, json, os, urllib.request
from pathlib import Path

BASE = os.environ['PONY_API_BASE']                      # https://…/api/v1
SECRET = Path(os.environ['PONY_API_KEY_FILE']).read_text().strip()

def call(method, path, body=None, key=None):
    headers = {'Authorization': 'Bearer ' + SECRET, 'Accept': 'application/json'}
    data = None
    if body is not None:
        data = json.dumps(body).encode()
        headers.update({'Content-Type': 'application/json', 'Idempotency-Key': key})
    request = urllib.request.Request(BASE + path, data=data, headers=headers, method=method)
    with urllib.request.urlopen(request, timeout=60) as response:   # HTTPError carries the JSON error
        return json.load(response)

def mail_pdf(pdf_path, reference, recipient, sender):
    """One business event (e.g. an invoice number) -> at most one letter."""
    draft = call('POST', '/drafts', {'title': reference, 'content_type': 'pdf', 'recipient': recipient,
                                     'sender': sender, 'content_policy_acknowledged': True}, reference + ':draft')
    draft = call('POST', f"/drafts/{draft['draft_id']}/attachments", {
        'version': draft['version'], 'kind': 'pdf', 'name': Path(pdf_path).name,
        'content_base64': base64.b64encode(Path(pdf_path).read_bytes()).decode(),
        'content_policy_acknowledged': True}, reference + ':pdf')
    proof = call('POST', f"/drafts/{draft['draft_id']}/proofs", {'version': draft['version']}, reference + ':proof')
    if proof.get('errors'):
        raise RuntimeError(proof['errors'])
    quote = call('POST', '/send-quotes', {'draft_id': draft['draft_id'], 'version': draft['version'],
                 'proof_id': proof['proof_id'], 'client_reference': reference}, reference + ':quote')
    return call('POST', '/orders', {'send_intent_id': quote['send_intent_id'], 'quote_id': quote['quote_id'],
                'proof_id': quote['proof_id'], 'expected_total_minor': quote['total_minor'], 'currency': 'USD'},
                reference + ':send')