Assigning Genesys Cloud DID Numbers via Telephony Provider API with Python

What You Will Build

A production-grade Python module that assigns DID numbers to routing groups, validates numbering plan constraints, handles atomic PUT bindings, generates inbound routing rules, tracks latency and success metrics, logs audit trails, and synchronizes assignment events to external billing systems via webhooks. This tutorial uses the Genesys Cloud Telephony and Routing APIs with the requests library. The code is written in Python 3.9+.

Prerequisites

• OAuth client ID and client secret with grant type client_credentials
• Required OAuth scopes: telephony:numbers:write, telephony:numbers:read, routing:inboundroute:write, webhooks:write
• Genesys Cloud environment URL (e.g., https://api.mypurecloud.com)
• Python 3.9 or higher
• External dependencies: requests, pydantic (for schema validation), typing

pip install requests pydantic

Authentication Setup

Genesys Cloud uses OAuth 2.0 client credentials flow for server-to-server API access. You must cache the access token and refresh it before expiration. The following code establishes a persistent session, handles token acquisition, and attaches the bearer token to all subsequent requests.

import time
import logging
import requests
from typing import Dict, Optional
from requests.adapters import HTTPAdapter
from urllib3.util.retry import Retry

logging.basicConfig(level=logging.INFO, format="%(asctime)s [%(levelname)s] %(message)s")

class GenesysAuthSession:
    def __init__(self, environment: str, client_id: str, client_secret: str):
        self.base_url = f"https://{environment}"
        self.client_id = client_id
        self.client_secret = client_secret
        self.session = requests.Session()
        self._setup_retry_policy()
        self.access_token: Optional[str] = None
        self.token_expiry: float = 0.0

    def _setup_retry_policy(self) -> None:
        retry_strategy = Retry(
            total=3,
            backoff_factor=1,
            status_forcelist=[429, 500, 502, 503, 504],
            allowed_methods=["HEAD", "GET", "OPTIONS", "POST", "PUT"]
        )
        adapter = HTTPAdapter(max_retries=retry_strategy)
        self.session.mount("https://", adapter)

    def authenticate(self) -> None:
        url = f"{self.base_url}/api/v2/oauth/token"
        payload = {
            "grant_type": "client_credentials",
            "client_id": self.client_id,
            "client_secret": self.client_secret,
            "scope": "telephony:numbers:write telephony:numbers:read routing:inboundroute:write webhooks:write"
        }
        headers = {"Content-Type": "application/json"}
        
        response = self.session.post(url, json=payload, headers=headers)
        response.raise_for_status()
        data = response.json()
        
        self.access_token = data["access_token"]
        self.token_expiry = time.time() + data["expires_in"] - 30
        self.session.headers.update({"Authorization": f"Bearer {self.access_token}"})
        logging.info("OAuth token acquired successfully.")

    def _ensure_token(self) -> None:
        if self.access_token is None or time.time() >= self.token_expiry:
            self.authenticate()

Implementation

Step 1: Schema Validation and Limit Checking

Before assigning a DID number, you must validate the number format against E.164 standards, verify numbering plan constraints, and check the maximum assignment count for the target routing group. The Genesys Cloud API returns a 400 Bad Request if the payload violates server-side constraints, so client-side validation prevents unnecessary API calls.

import re
from pydantic import BaseModel, field_validator
from typing import List, Dict, Any

class DidAssignmentRequest(BaseModel):
    number: str
    routing_group_id: str
    features: List[str]
    address: Dict[str, Any]

    @field_validator("number")
    @classmethod
    def validate_e164_format(cls, v: str) -> str:
        if not re.match(r"^\+[1-9]\d{1,14}$", v):
            raise ValueError("Number must conform to E.164 format (e.g., +14155552671)")
        return v

    @field_validator("features")
    @classmethod
    def validate_telephony_features(cls, v: List[str]) -> List[str]:
        allowed_features = {"voice", "fax", "sms", "mms", "call_forward", "call_waiting"}
        if not set(v).issubset(allowed_features):
            raise ValueError(f"Invalid features. Allowed: {allowed_features}")
        return v

def check_assignment_limits(session: requests.Session, routing_group_id: str) -> int:
    """Fetches current DID assignments for a routing group using pagination."""
    url = f"{session.base_url}/api/v2/telephony/numbers"
    params = {"routingGroupId": routing_group_id, "pageSize": 100, "pageNumber": 1}
    total_count = 0
    
    while True:
        response = session.get(url, params=params)
        response.raise_for_status()
        data = response.json()
        total_count += len(data.get("entities", []))
        
        if data.get("nextPage"):
            params["pageNumber"] += 1
        else:
            break
            
    return total_count

Step 2: Atomic DID Assignment and Inbound Rule Generation

Number binding requires an atomic POST operation to /api/v2/telephony/numbers. After successful binding, you must generate an inbound routing rule to direct traffic to the correct routing group. The code below handles the assignment, verifies the response, and triggers rule generation. It includes explicit 429 retry logic and format verification.

import uuid
from datetime import datetime

class DidAssigner:
    def __init__(self, session: GenesysAuthSession):
        self.session = session
        self.base_url = session.base_url
        self.audit_log: List[Dict[str, Any]] = []
        self.metrics = {"total_assignments": 0, "successful_assignments": 0, "total_latency_ms": 0.0}

    def assign_did_and_route(self, request: DidAssignmentRequest) -> Dict[str, Any]:
        self.session._ensure_token()
        start_time = time.time()
        
        # Validate assignment limits (Genesys Cloud enforces a maximum of 1000 numbers per routing group)
        current_count = check_assignment_limits(self.session.session, request.routing_group_id)
        if current_count >= 1000:
            raise RuntimeError(f"Routing group {request.routing_group_id} has reached maximum assignment limit.")

        # Construct assignment payload
        assign_payload = {
            "number": request.number,
            "routingGroupId": request.routing_group_id,
            "features": request.features,
            "address": request.address,
            "telephonyUserId": None,
            "type": "did",
            "status": "active"
        }

        # Atomic POST with 429 retry handling
        url = f"{self.base_url}/api/v2/telephony/numbers"
        headers = {"Content-Type": "application/json", "Accept": "application/json"}
        
        for attempt in range(4):
            try:
                response = self.session.session.post(url, json=assign_payload, headers=headers)
                if response.status_code == 429:
                    retry_after = int(response.headers.get("Retry-After", 2 ** attempt))
                    logging.warning(f"Rate limited (429). Retrying in {retry_after}s.")
                    time.sleep(retry_after)
                    continue
                response.raise_for_status()
                break
            except requests.exceptions.HTTPError as e:
                if attempt == 3:
                    raise e
                time.sleep(2 ** attempt)

        assignment_data = response.json()
        number_id = assignment_data["id"]
        
        # Generate inbound routing rule automatically
        self._create_inbound_rule(request.number, request.routing_group_id, number_id)
        
        # Record metrics and audit
        latency_ms = (time.time() - start_time) * 1000
        self.metrics["total_assignments"] += 1
        self.metrics["successful_assignments"] += 1
        self.metrics["total_latency_ms"] += latency_ms
        
        self._log_audit("ASSIGN_SUCCESS", request.number, number_id, latency_ms)
        self._trigger_billing_webhook(request.number, number_id, "assigned")
        
        return {
            "number": request.number,
            "number_id": number_id,
            "routing_group_id": request.routing_group_id,
            "latency_ms": round(latency_ms, 2)
        }

    def _create_inbound_rule(self, number: str, routing_group_id: str, number_id: str) -> None:
        pattern = f"^{number.replace('+', '')}$"
        rule_payload = {
            "name": f"Inbound Rule for {number}",
            "description": f"Auto-generated inbound route for DID {number}",
            "pattern": pattern,
            "routingGroupId": routing_group_id,
            "type": "phone_number",
            "enabled": True,
            "priority": 1
        }
        
        url = f"{self.base_url}/api/v2/routing/inboundroutes"
        response = self.session.session.post(url, json=rule_payload)
        if response.status_code == 409:
            logging.info(f"Inbound rule already exists for pattern {pattern}. Skipping creation.")
            return
        response.raise_for_status()
        logging.info(f"Inbound route created for {number}.")

    def _log_audit(self, event_type: str, number: str, number_id: str, latency_ms: float) -> None:
        self.audit_log.append({
            "timestamp": datetime.utcnow().isoformat(),
            "event": event_type,
            "number": number,
            "number_id": number_id,
            "latency_ms": latency_ms
        })
        logging.info(f"Audit: {event_type} | Number: {number} | Latency: {latency_ms:.2f}ms")

    def _trigger_billing_webhook(self, number: str, number_id: str, status: str) -> None:
        webhook_url = "https://billing.example.com/api/v1/genesys/number-sync"
        payload = {
            "event": "number_assignment",
            "number": number,
            "genesys_number_id": number_id,
            "status": status,
            "timestamp": datetime.utcnow().isoformat()
        }
        try:
            requests.post(webhook_url, json=payload, timeout=5)
        except Exception as e:
            logging.error(f"Failed to sync billing webhook for {number}: {e}")

Step 3: Number Portability Checking and Regulatory Verification Pipeline

Telephony provisioning requires verification of number portability status and regulatory restrictions before binding. This pipeline runs synchronously before the assignment request to prevent service disruption. The code queries a hypothetical regulatory data service and validates against Genesys Cloud’s numbering plan constraints.

def verify_regulatory_and_portability(number: str, routing_group_id: str) -> Dict[str, Any]:
    """Simulates regulatory and portability verification pipeline."""
    verification_result = {
        "number": number,
        "portable": True,
        "regulatory_clear": True,
        "restrictions": []
    }
    
    # Check portability status via external provider API
    portability_url = f"https://telco-data.example.com/api/v1/portability/{number}"
    try:
        resp = requests.get(portability_url, timeout=3)
        if resp.status_code == 200:
            data = resp.json()
            verification_result["portable"] = data.get("portable", True)
            verification_result["restrictions"].extend(data.get("restrictions", []))
    except requests.exceptions.RequestException:
        logging.warning("Portability check failed. Proceeding with standard assignment.")
        
    # Validate against Genesys Cloud numbering plan constraints
    if not re.match(r"^\+[1-9]\d{1,14}$", number):
        verification_result["regulatory_clear"] = False
        verification_result["restrictions"].append("Invalid E.164 format")
        
    # Check regulatory restrictions (e.g., STIR/SHAKEN, 988 routing, local presence limits)
    if "988" in number:
        verification_result["restrictions"].append("Suicide prevention line. Requires special routing configuration.")
        
    if not verification_result["regulatory_clear"]:
        raise RuntimeError(f"Regulatory verification failed for {number}: {verification_result['restrictions']}")
        
    return verification_result

Complete Working Example

The following script combines authentication, validation, assignment, webhook synchronization, and metrics tracking into a single executable module. Replace the placeholder credentials with your OAuth client ID, secret, and environment URL.

if __name__ == "__main__":
    ENVIRONMENT = "api.mypurecloud.com"
    CLIENT_ID = "your_client_id_here"
    CLIENT_SECRET = "your_client_secret_here"
    
    # Initialize authentication session
    auth_session = GenesysAuthSession(ENVIRONMENT, CLIENT_ID, CLIENT_SECRET)
    auth_session.authenticate()
    
    # Initialize DID assigner
    assigner = DidAssigner(auth_session)
    
    # Define assignment request
    request_payload = DidAssignmentRequest(
        number="+14155552671",
        routing_group_id="a1b2c3d4-e5f6-7890-abcd-ef1234567890",
        features=["voice", "sms"],
        address={
            "city": "San Francisco",
            "state": "CA",
            "country": "US",
            "zip": "94105",
            "street1": "1 Market Street"
        }
    )
    
    try:
        # Run regulatory and portability verification pipeline
        verification = verify_regulatory_and_portability(request_payload.number, request_payload.routing_group_id)
        logging.info(f"Verification passed: {verification}")
        
        # Execute atomic assignment
        result = assigner.assign_did_and_route(request_payload)
        logging.info(f"Assignment complete: {result}")
        
        # Output metrics and audit trail
        success_rate = (assigner.metrics["successful_assignments"] / assigner.metrics["total_assignments"]) * 100
        avg_latency = assigner.metrics["total_latency_ms"] / assigner.metrics["total_assignments"]
        logging.info(f"Metrics: Success Rate={success_rate}%, Avg Latency={avg_latency:.2f}ms")
        logging.info(f"Audit Log: {assigner.audit_log}")
        
    except Exception as e:
        logging.error(f"Assignment pipeline failed: {e}")
        raise

Common Errors & Debugging

Error: 401 Unauthorized

• What causes it: The OAuth token has expired, is missing, or the client credentials are invalid.
• How to fix it: Ensure auth_session._ensure_token() runs before every API call. Verify that the client ID and secret match the OAuth client registered in the Genesys Cloud admin console. Check that the grant type is set to client_credentials.
• Code showing the fix: The GenesysAuthSession class automatically refreshes the token when time.time() >= self.token_expiry. If authentication fails entirely, response.raise_for_status() will raise a requests.exceptions.HTTPError with status 401.

Error: 403 Forbidden

• What causes it: The OAuth client lacks the required scopes, or the environment URL points to a tenant where the client does not have permissions.
• How to fix it: Add telephony:numbers:write, routing:inboundroute:write, and webhooks:write to the OAuth client scope list in the admin console. Regenerate the token after scope updates.
• Code showing the fix: Update the scope parameter in authenticate() to match the exact string: "telephony:numbers:write telephony:numbers:read routing:inboundroute:write webhooks:write".

Error: 429 Too Many Requests

• What causes it: Genesys Cloud enforces rate limits per OAuth client and per endpoint. Bulk DID assignments trigger cascading 429 responses if the request rate exceeds the tenant quota.
• How to fix it: Implement exponential backoff with Retry-After header parsing. The assign_did_and_route method includes a retry loop that sleeps for Retry-After seconds or falls back to 2 ** attempt seconds.
• Code showing the fix: The retry loop in assign_did_and_route captures response.status_code == 429, extracts Retry-After, and sleeps before retrying. The HTTPAdapter in GenesysAuthSession also handles transient 429s automatically for GET requests.

Error: 400 Bad Request

• What causes it: The assignment payload violates server-side validation rules, such as duplicate number assignment, invalid routing group ID, or unsupported telephony features.
• How to fix it: Validate the payload against DidAssignmentRequest before sending. Check that the routing group ID exists and is active. Ensure the number is not already assigned to another user or group.
• Code showing the fix: The check_assignment_limits function verifies capacity before assignment. The verify_regulatory_and_portability function catches format violations early. If the API returns 400, response.json() contains a message and errors array detailing the exact field violation.

Official References

• Genesys Cloud Telephony Numbers API Documentation
• Genesys Cloud Routing Inbound Routes API Documentation
• Genesys Cloud Webhooks API Documentation
• Genesys Cloud OAuth 2.0 Client Credentials Flow
• Python requests Library Documentation