riposte-marketplace/integrations/ovhcloud/scripts/get_oncall_ladder.py

import json, os, sys, hashlib, time, urllib.parse, urllib.request, urllib.error


def _cfg():
    return json.loads(os.environ.get("INTEGRATION_SECRETS", "{}"))


def _inputs():
    return json.loads(os.environ.get("INTEGRATION_INPUTS", "{}"))


# ── authentication ──────────────────────────────────────────────────────────
#
# TWO SCHEMES, because OVHcloud now offers two and an operator does not always get
# to choose. The historical one signs each request with an application key/secret
# plus a consumer key. The newer SERVICE ACCOUNT is OAuth2 client-credentials, and
# it is what the control panel offers when application keys are not available on
# the account.
#
# Which one is in use is decided by what was filled in, not by a mode selector:
# a client_id and a client_secret mean the service account, anything else falls
# back to the signed scheme. One less field to get wrong, and an instance created
# before service accounts existed keeps working untouched.
_TOKEN_HOSTS = {
    "eu": "https://www.ovh.com",
    "ca": "https://ca.ovh.com",
    "us": "https://us.ovhcloud.com",
}
_CACHE = {}


def _oauth(cfg):
    return bool(str(cfg.get("client_id") or "").strip() and str(cfg.get("client_secret") or "").strip())


def _endpoint(cfg):
    """The API base, exactly as configured.

    IT USED TO REWRITE /1.0 TO /v1 FOR A SERVICE ACCOUNT, on the strength of a
    documentation example that showed OAuth2 against a /v1 path. That was wrong and
    cost two rounds of debugging: OVH's own API console issues Bearer requests
    against /1.0, and /v1 — which exists, and answers 401 unauthenticated like any
    live route — answers 500 with an empty body for a token on the telephony
    routes. A failure with no message, produced by a helpful rewrite nobody asked
    for.

    So the endpoint is now whatever was typed, for both schemes. Both spellings
    work for the signed scheme; only the configured one is used, and OVH's console
    is the place to copy it from.
    """
    return (str(cfg.get("endpoint") or "https://eu.api.ovh.com/1.0")).rstrip("/")


def _token_url(cfg):
    explicit = str(cfg.get("oauth_token_url") or "").strip()
    if explicit:
        return explicit
    host = urllib.parse.urlparse(_endpoint(cfg)).netloc
    region = host.split(".")[0] if host else "eu"
    return _TOKEN_HOSTS.get(region, _TOKEN_HOSTS["eu"]) + "/auth/oauth2/token"


def _bearer(cfg):
    """The service account's access token.

    CACHED FOR THE LIFE OF THE PROCESS, which is not a micro-optimisation: publishing
    an on-call ladder makes a dozen or more API calls, and a token request in front
    of each one would triple the traffic and the time — on the path that runs every
    time the rota turns.
    """
    if _CACHE.get("token"):
        return _CACHE["token"]
    data = urllib.parse.urlencode({
        "grant_type": "client_credentials",
        "client_id": str(cfg.get("client_id", "")).strip(),
        "client_secret": str(cfg.get("client_secret", "")).strip(),
        # The scope the service account was granted in the control panel is what
        # actually bounds it; "all" here asks for everything that account may do.
        # Narrow the SERVICE ACCOUNT's own IAM policy rather than this value.
        "scope": "all",
    }).encode("utf-8")
    req = urllib.request.Request(
        _token_url(cfg), data=data, method="POST",
        headers={"Content-Type": "application/x-www-form-urlencoded", "Accept": "application/json"})
    with urllib.request.urlopen(req, timeout=30) as r:
        payload = json.loads(r.read() or b"{}")
    token = payload.get("access_token")
    if not token:
        raise Exception("the service account returned no access token: " + json.dumps(payload)[:200])
    _CACHE["token"] = token
    return token


def _time_offset(cfg):
    """Seconds between this clock and OVH's, read once.

    The signature carries a timestamp and OVH refuses one that has drifted, so the
    server's own time is the safe source. Read ONCE and applied as an offset rather
    than fetched per request: the ladder makes many calls, and an extra round trip
    in front of each was doubling them.
    """
    if "offset" not in _CACHE:
        req = urllib.request.Request(_endpoint(cfg) + "/auth/time", method="GET")
        with urllib.request.urlopen(req, timeout=30) as r:
            server = int(r.read().decode("utf-8", "replace").strip())
        _CACHE["offset"] = server - int(time.time())
    return _CACHE["offset"]


def request(method, path, cfg, body=None):
    url = _endpoint(cfg) + path
    body_str = json.dumps(body) if body is not None else ""
    headers = {"Accept": "application/json"}
    if _oauth(cfg):
        headers["Authorization"] = "Bearer " + _bearer(cfg)
    else:
        app_key = str(cfg.get("application_key", "")).strip()
        app_secret = str(cfg.get("application_secret", "")).strip()
        consumer = str(cfg.get("consumer_key", "")).strip()
        if not (app_key and app_secret and consumer):
            raise Exception(
                "this instance has no credentials: fill in either a service account "
                "(client_id + client_secret) or the application key, secret and consumer key")
        ts = str(int(time.time()) + _time_offset(cfg))
        to_sign = app_secret + "+" + consumer + "+" + method.upper() + "+" + url + "+" + body_str + "+" + ts
        headers["X-Ovh-Application"] = app_key
        headers["X-Ovh-Consumer"] = consumer
        headers["X-Ovh-Timestamp"] = ts
        headers["X-Ovh-Signature"] = "$1$" + hashlib.sha1(to_sign.encode("utf-8")).hexdigest()
    data = None
    if body is not None:
        data = body_str.encode("utf-8")
        headers["Content-Type"] = "application/json"
    req = urllib.request.Request(url, data=data, headers=headers, method=method)
    with urllib.request.urlopen(req, timeout=60) as r:
        raw = r.read()
        return json.loads(raw) if raw else {}


def _run(fn):
    try:
        print(json.dumps(fn(_cfg(), _inputs())))
    except urllib.error.HTTPError as e:
        print(json.dumps({"error": "HTTP " + str(e.code), "detail": e.read().decode("utf-8", "replace")}))
        sys.exit(1)
    except Exception as e:
        print(json.dumps({"error": str(e)}))
        sys.exit(1)


# ── the call queue ──────────────────────────────────────────────────────────
#
# THE SAME COORDINATES FOR EVERY ON-CALL COMMAND, hence this block: the billing
# account, the service (the number the queue hangs from) and the queue itself.
# Repeated in each script rather than imported, because the marketplace collects
# loose *.py files and every command has to stand on its own.
def _telephony(cfg):
    ba = str(cfg.get("telephony_billing_account") or "").strip()
    service = str(cfg.get("telephony_service") or "").strip()
    if not ba or not service:
        raise Exception(
            "this instance has no telephony coordinates: set telephony_billing_account "
            "(e.g. fr-xxxxx-1) and telephony_service (the call queue's number, 0033xxxxxxxxx)")
    return ba, service


# The call queue lives under ONE OF TWO PRODUCTS, and which one is not something an
# operator can see: the control panel says "File d'appels" for both. OVH files them
# under easyHunting or under ovhPabx depending on the offer the number carries, and
# the hunting routes underneath are identical either way.
#
# Assuming easyHunting is what this did first, and the symptom was a 404 reading
# "This service does not exist" — which sounds like a wrong number and is in fact a
# wrong product. So it is DISCOVERED, once per process, and a failure says what does
# exist rather than what does not.
_PRODUCTS = ("easyHunting", "ovhPabx")


def _product(cfg):
    if _CACHE.get("product"):
        return _CACHE["product"]
    ba, service = _telephony(cfg)
    found = {}
    for product in _PRODUCTS:
        names = request("GET", "/telephony/" + urllib.parse.quote(ba, safe="") + "/" + product, cfg) or []
        found[product] = [str(n) for n in names]
        if service in found[product]:
            _CACHE["product"] = product
            return product
    raise Exception(
        "no call queue named %s on %s. easyHunting holds [%s]; ovhPabx holds [%s]. "
        "Set telephony_service to one of those names, or configure the number as a "
        "call queue in the control panel first."
        % (service, ba, ", ".join(found.get("easyHunting") or ["-"]), ", ".join(found.get("ovhPabx") or ["-"])))


def _base(cfg):
    ba, service = _telephony(cfg)
    return ("/telephony/" + urllib.parse.quote(ba, safe="") + "/" + _product(cfg) +
            "/" + urllib.parse.quote(service, safe=""))


def _queue_id(cfg):
    """The queue to act on.

    Configured explicitly, or discovered when the service holds exactly one, which is
    the normal shape. AMBIGUITY IS REFUSED RATHER THAN GUESSED: picking the first of
    several would publish the on-call ladder into whichever queue OVH happened to
    list first, and the symptom is a number that rings the wrong team at 03:00.
    """
    configured = str(cfg.get("telephony_queue_id") or "").strip()
    if configured:
        return configured
    ids = request("GET", _base(cfg) + "/hunting/queue", cfg)
    if not isinstance(ids, list) or not ids:
        raise Exception("this service holds no call queue; create one in the control panel first")
    if len(ids) > 1:
        raise Exception("this service holds %d queues (%s) - set telephony_queue_id to say which one" %
                        (len(ids), ", ".join(str(i) for i in ids)))
    return str(ids[0])


def _ovh_number(raw):
    """OVH writes external numbers in 00-prefixed international form.

    A "+" is accepted nowhere in a phoneNumber field, so a ladder handed straight from
    Riposte - which speaks E.164 - would be refused number by number, and the on-call
    ladder would silently stay as it was.
    """
    s = "".join(ch for ch in str(raw) if ch.isdigit() or ch == "+").strip()
    if s.startswith("+"):
        return "00" + s[1:]
    return s


def _e164(raw):
    """The inverse, so a readback can be compared with what Riposte published."""
    s = "".join(ch for ch in str(raw) if ch.isdigit() or ch == "+").strip()
    if s.startswith("+"):
        return s
    if s.startswith("00"):
        return "+" + s[2:]
    return s


def _agents(cfg):
    """Every agent of the service, as {agentId: agent}."""
    out = {}
    for agent_id in request("GET", _base(cfg) + "/hunting/agent", cfg) or []:
        out[str(agent_id)] = request("GET", _base(cfg) + "/hunting/agent/" + str(agent_id), cfg)
    return out


# ── get_oncall_ladder ───────────────────────────────────────────────────────
#
# What the queue ACTUALLY holds, in its order. Riposte's test button shows it
# beside the ladder the rota resolves to, which is the only way to catch a
# publication that failed hours ago or a change somebody made by hand.
#
# Reads only. It places no call and writes nothing.
def main(cfg, inputs):
    base = _base(cfg)
    queue_id = _queue_id(cfg)
    queue = request("GET", base + "/hunting/queue/" + str(queue_id), cfg)

    rungs = []
    for agent_id in request("GET", base + "/hunting/queue/" + str(queue_id) + "/agent", cfg) or []:
        membership = request("GET", base + "/hunting/queue/" + str(queue_id) + "/agent/" + str(agent_id), cfg)
        agent = request("GET", base + "/hunting/agent/" + str(agent_id), cfg)
        rungs.append({
            "position": membership.get("position") or 0,
            "number": _e164(agent.get("number")),
            "status": agent.get("status"),
            "timeout": agent.get("timeout"),
        })
    rungs.sort(key=lambda r: r["position"])

    # ONLY THE AVAILABLE AGENTS ARE THE LADDER. A logged-out agent is somebody who
    # stepped off it and whose row we keep; returning them would make every readback
    # disagree with what Riposte published, which is exactly the alarm this command
    # exists to raise honestly.
    numbers = [r["number"] for r in rungs if r.get("status") == "available" and r["number"]]
    timeouts = [r["timeout"] for r in rungs if r.get("status") == "available" and r.get("timeout")]

    return {
        "ok": True,
        "numbers": numbers,
        "ring_seconds": timeouts[0] if timeouts else None,
        "queue_id": queue_id,
        "strategy": queue.get("strategy"),
        # Said plainly rather than left to be inferred from the strategy string: a
        # queue ringing everybody at once takes the same list and ignores its order,
        # and the ladder Riposte published would be a fiction.
        "sequential": queue.get("strategy") == "sequentiallyByAgentOrder",
        "rungs": rungs,
    }


_run(main)