Aggregating Genesys Cloud Telephony CDRs with Python SDK for Billing Alignment

What You Will Build

• A Python module that fetches call detail records via the Genesys Cloud Telephony API, processes them in validated batches, calculates costs based on duration and rate tiers, checks for duplicate legs, and synchronizes aggregated results with an external ERP system via webhook.
• This tutorial uses the Genesys Cloud Python SDK (genesyscloud) alongside httpx and pydantic for schema validation and external synchronization.
• The implementation is written in Python 3.9+ and covers authentication, pagination, batch processing, error handling, latency tracking, and audit logging.

Prerequisites

• Genesys Cloud OAuth client credentials (client ID, client secret, private key, and private key password)
• Required OAuth scope: telephony:call:read
• Python 3.9 or higher
• External dependencies: genesyscloud>=2.0.0, httpx>=0.25.0, pydantic>=2.0.0, pydantic[email]
• Access to an external ERP webhook endpoint for invoice synchronization

Authentication Setup

The Genesys Cloud Python SDK handles JWT bearer token acquisition, caching, and automatic refresh when configured with a private key. You must initialize the PureCloudPlatformClientV2 configuration before making any API calls.

import os
from genesyscloud.rest import Configuration

def build_genesys_config() -> Configuration:
    config = Configuration()
    config.host = "https://api.mypurecloud.com"
    config.access_token = os.getenv("GENESYS_ACCESS_TOKEN")
    
    if not config.access_token:
        config.oauth_client_id = os.getenv("GENESYS_CLIENT_ID")
        config.oauth_client_secret = os.getenv("GENESYS_CLIENT_SECRET")
        config.oauth_private_key = os.getenv("GENESYS_PRIVATE_KEY")
        config.oauth_private_key_password = os.getenv("GENESYS_PRIVATE_KEY_PASSWORD")
        config.oauth_jwt_grant_type = "urn:ietf:params:oauth:grant-type:jwt-bearer"
        
    return config

The SDK caches the token in memory and automatically requests a new token when the current one expires. If you provide a static access token, the SDK will use it until it fails with a 401 status code.

Implementation

Step 1: Query CDRs with Pagination and Batch Limits

The Telephony API returns call detail records in paginated batches. You must construct a query payload with a date range, set a size limit to prevent payload overflow, and iterate using the nextPageToken. The endpoint supports a maximum batch size of 1000 records, but billing systems typically enforce stricter limits. This example caps batches at 500 records.

import time
import httpx
from genesyscloud.api_client import ApiClient
from genesyscloud.telephony.api import TelephonyApi
from genesyscloud.telephony.model import QueryTelephonyCallsDetailsRequest

def fetch_cdr_batches(api_client: ApiClient, start_time: str, end_time: str, batch_size: int = 500):
    telephony_api = TelephonyApi(api_client)
    page_token = None
    batch_count = 0
    latency_tracker = []
    
    while True:
        request_body = {
            "query": {
                "filter": {
                    "field": "startTime",
                    "op": "between",
                    "value": [start_time, end_time]
                }
            },
            "size": batch_size,
            "nextPageToken": page_token
        }
        
        start_req = time.perf_counter()
        try:
            response = telephony_api.post_telephony_calls_details_query(
                body=QueryTelephonyCallsDetailsRequest.from_dict(request_body)
            )
            elapsed = time.perf_counter() - start_req
            latency_tracker.append(elapsed)
            
            if not response.entities:
                break
                
            batch_count += 1
            yield response.entities, elapsed
            
            page_token = response.next_page_token
            if not page_token:
                break
                
        except httpx.HTTPStatusError as e:
            if e.response.status_code == 429:
                retry_after = int(e.response.headers.get("Retry-After", 2))
                time.sleep(retry_after)
                continue
            raise

Expected Response Structure:

{
  "entities": [
    {
      "id": "call-uuid-1",
      "startTime": "2024-01-15T10:00:00Z",
      "answerTime": "2024-01-15T10:00:02Z",
      "endTime": "2024-01-15T10:05:30Z",
      "direction": "outbound",
      "from": {"number": "+15550100", "name": "Agent 1"},
      "to": {"number": "+15550200", "name": "Customer A"},
      "legIndex": 0,
      "callId": "parent-call-uuid"
    }
  ],
  "nextPageToken": "eyJwYWdlIjoyLCJzaXplIjo1MDB9",
  "pageSize": 500,
  "total": 1250
}

The 429 status code triggers a retry loop using the Retry-After header. If the header is missing, the code defaults to a 2-second delay. The 401 and 403 errors propagate immediately because they indicate credential or scope misconfiguration.

Step 2: Process Batches with Duration Calculation and Duplicate Leg Checking

Each batch requires duration calculation, rate tier evaluation, and duplicate leg detection. You must calculate duration in seconds using ISO 8601 timestamps, verify against a tariff configuration via an atomic GET operation, and filter duplicate legs using a composite key of callId and legIndex.

from datetime import datetime, timezone
from typing import List, Dict, Set
import httpx

def fetch_rate_tiers(base_url: str) -> Dict[str, float]:
    response = httpx.get(f"{base_url}/api/v1/tariffs/active")
    response.raise_for_status()
    return response.json()

def process_cdr_batch(cdr_entities: List[Dict], rate_tiers: Dict[str, float], seen_legs: Set[str]) -> List[Dict]:
    processed_records = []
    
    for cdr in cdr_entities:
        leg_key = f"{cdr.get('callId')}:{cdr.get('legIndex')}"
        if leg_key in seen_legs:
            continue
        seen_legs.add(leg_key)
        
        start_dt = datetime.fromisoformat(cdr["startTime"].replace("Z", "+00:00"))
        answer_dt = datetime.fromisoformat(cdr["answerTime"].replace("Z", "+00:00")) if cdr.get("answerTime") else start_dt
        end_dt = datetime.fromisoformat(cdr["endTime"].replace("Z", "+00:00"))
        
        duration_seconds = (end_dt - answer_dt).total_seconds()
        if duration_seconds <= 0:
            continue
            
        destination_country = cdr.get("to", {}).get("countryCode", "US")
        rate_per_second = rate_tiers.get(destination_country, 0.01)
        
        processed_records.append({
            "cdr_reference": cdr["id"],
            "call_id": cdr["callId"],
            "duration_seconds": round(duration_seconds, 2),
            "rate_per_second": rate_per_second,
            "calculated_cost": round(duration_seconds * rate_per_second, 4),
            "tariff_country": destination_country,
            "direction": cdr["direction"]
        })
        
    return processed_records

The duration_seconds calculation excludes pre-answer time to align with standard billing practices. The seen_legs set prevents double-charging when Genesys Cloud returns multiple legs for the same call session. The atomic GET operation to /api/v1/tariffs/active represents your internal billing service. You must replace the URL with your actual tariff configuration endpoint.

Step 3: Validate Schema and Trigger ERP Invoice Sync

Before transmitting aggregated data to an external system, you must validate the payload against billing constraints. Pydantic enforces field types, maximum values, and required structures. After validation, the code triggers an automatic invoice webhook and records an audit log.

from pydantic import BaseModel, Field, ValidationError
import json
import logging

class CdrAggregationPayload(BaseModel):
    cdr_reference: str
    call_id: str
    duration_seconds: float = Field(le=86400, ge=0)
    rate_per_second: float = Field(ge=0)
    calculated_cost: float = Field(ge=0)
    tariff_country: str
    direction: str

class BillingAggregation(BaseModel):
    batch_id: str
    records: List[CdrAggregationPayload] = Field(max_length=500)
    total_cost: float
    record_count: int
    aggregation_timestamp: str

def validate_and_sync(batch_records: List[Dict], batch_id: str, webhook_url: str, logger: logging.Logger) -> Dict:
    validated_payloads = []
    validation_errors = []
    
    for rec in batch_records:
        try:
            validated_payloads.append(CdrAggregationPayload(**rec))
        except ValidationError as e:
            validation_errors.append({"cdr": rec.get("cdr_reference"), "errors": e.errors()})
            
    if validation_errors:
        logger.warning(f"Validation failures in batch {batch_id}: {validation_errors}")
        
    aggregation = BillingAggregation(
        batch_id=batch_id,
        records=validated_payloads,
        total_cost=sum(r.calculated_cost for r in validated_payloads),
        record_count=len(validated_payloads),
        aggregation_timestamp=datetime.now(timezone.utc).isoformat()
    )
    
    payload_json = aggregation.model_dump_json()
    
    response = httpx.post(webhook_url, content=payload_json, headers={"Content-Type": "application/json"})
    response.raise_for_status()
    
    audit_log = {
        "event": "cdr_aggregation_sync",
        "batch_id": batch_id,
        "records_processed": aggregation.record_count,
        "total_cost": aggregation.total_cost,
        "status": "success",
        "webhook_status": response.status_code,
        "timestamp": datetime.now(timezone.utc).isoformat()
    }
    logger.info(json.dumps(audit_log))
    
    return audit_log

The BillingAggregation schema enforces a maximum record count of 500 to prevent payload rejection. The le=86400 constraint on duration_seconds prevents runaway billing calculations. The audit log records success metrics and webhook status for governance tracking.

Complete Working Example

This script combines authentication, pagination, batch processing, validation, and synchronization into a single executable module. Replace the environment variables and webhook URL before execution.

import os
import time
import uuid
import json
import logging
import httpx
from datetime import datetime, timezone
from typing import List, Dict, Set
from genesyscloud.rest import Configuration
from genesyscloud.api_client import ApiClient
from genesyscloud.telephony.api import TelephonyApi
from genesyscloud.telephony.model import QueryTelephonyCallsDetailsRequest
from pydantic import BaseModel, Field, ValidationError

class CdrAggregationPayload(BaseModel):
    cdr_reference: str
    call_id: str
    duration_seconds: float = Field(le=86400, ge=0)
    rate_per_second: float = Field(ge=0)
    calculated_cost: float = Field(ge=0)
    tariff_country: str
    direction: str

class BillingAggregation(BaseModel):
    batch_id: str
    records: List[CdrAggregationPayload] = Field(max_length=500)
    total_cost: float
    record_count: int
    aggregation_timestamp: str

class CdrAggregator:
    def __init__(self, config: Configuration, tariff_url: str, webhook_url: str):
        self.api_client = ApiClient(config)
        self.telephony_api = TelephonyApi(self.api_client)
        self.tariff_url = tariff_url
        self.webhook_url = webhook_url
        self.seen_legs: Set[str] = set()
        self.latency_log: List[float] = []
        self.success_count = 0
        self.total_batches = 0
        self.logger = logging.getLogger("cdr_aggregator")
        self.logger.setLevel(logging.INFO)
        handler = logging.StreamHandler()
        handler.setFormatter(logging.Formatter("%(asctime)s - %(levelname)s - %(message)s"))
        self.logger.addHandler(handler)

    def _fetch_rate_tiers(self) -> Dict[str, float]:
        response = httpx.get(f"{self.tariff_url}/api/v1/tariffs/active")
        response.raise_for_status()
        return response.json()

    def _process_batch(self, entities: List[Dict], rate_tiers: Dict[str, float]) -> List[Dict]:
        processed = []
        for cdr in entities:
            leg_key = f"{cdr.get('callId')}:{cdr.get('legIndex')}"
            if leg_key in self.seen_legs:
                continue
            self.seen_legs.add(leg_key)
            
            start_dt = datetime.fromisoformat(cdr["startTime"].replace("Z", "+00:00"))
            answer_dt = datetime.fromisoformat(cdr["answerTime"].replace("Z", "+00:00")) if cdr.get("answerTime") else start_dt
            end_dt = datetime.fromisoformat(cdr["endTime"].replace("Z", "+00:00"))
            
            duration_seconds = (end_dt - answer_dt).total_seconds()
            if duration_seconds <= 0:
                continue
                
            dest_country = cdr.get("to", {}).get("countryCode", "US")
            rate = rate_tiers.get(dest_country, 0.01)
            
            processed.append({
                "cdr_reference": cdr["id"],
                "call_id": cdr["callId"],
                "duration_seconds": round(duration_seconds, 2),
                "rate_per_second": rate,
                "calculated_cost": round(duration_seconds * rate, 4),
                "tariff_country": dest_country,
                "direction": cdr["direction"]
            })
        return processed

    def _sync_batch(self, batch_records: List[Dict], batch_id: str) -> Dict:
        validated = []
        for rec in batch_records:
            try:
                validated.append(CdrAggregationPayload(**rec))
            except ValidationError as e:
                self.logger.warning(f"Validation failed for {rec.get('cdr_reference')}: {e.errors()}")
                
        aggregation = BillingAggregation(
            batch_id=batch_id,
            records=validated,
            total_cost=sum(r.calculated_cost for r in validated),
            record_count=len(validated),
            aggregation_timestamp=datetime.now(timezone.utc).isoformat()
        )
        
        response = httpx.post(self.webhook_url, content=aggregation.model_dump_json(), headers={"Content-Type": "application/json"})
        response.raise_for_status()
        
        audit = {
            "event": "cdr_aggregation_sync",
            "batch_id": batch_id,
            "records_processed": aggregation.record_count,
            "total_cost": aggregation.total_cost,
            "status": "success",
            "webhook_status": response.status_code,
            "timestamp": datetime.now(timezone.utc).isoformat()
        }
        self.logger.info(json.dumps(audit))
        return audit

    def run(self, start_time: str, end_time: str, batch_size: int = 500):
        rate_tiers = self._fetch_rate_tiers()
        page_token = None
        
        while True:
            request_body = {
                "query": {"filter": {"field": "startTime", "op": "between", "value": [start_time, end_time]}},
                "size": batch_size,
                "nextPageToken": page_token
            }
            
            start_req = time.perf_counter()
            try:
                response = self.telephony_api.post_telephony_calls_details_query(
                    body=QueryTelephonyCallsDetailsRequest.from_dict(request_body)
                )
                self.latency_log.append(time.perf_counter() - start_req)
                
                if not response.entities:
                    break
                    
                self.total_batches += 1
                batch_id = str(uuid.uuid4())
                processed = self._process_batch(response.entities, rate_tiers)
                
                if processed:
                    self._sync_batch(processed, batch_id)
                    self.success_count += 1
                
                page_token = response.next_page_token
                if not page_token:
                    break
                    
            except httpx.HTTPStatusError as e:
                if e.response.status_code == 429:
                    retry_after = int(e.response.headers.get("Retry-After", 2))
                    self.logger.warning(f"Rate limited. Retrying in {retry_after}s")
                    time.sleep(retry_after)
                    continue
                raise
                
        avg_latency = sum(self.latency_log) / len(self.latency_log) if self.latency_log else 0
        success_rate = (self.success_count / self.total_batches * 100) if self.total_batches > 0 else 0
        self.logger.info(f"Aggregation complete. Batches: {self.total_batches}, Success Rate: {success_rate:.2f}%, Avg Latency: {avg_latency:.3f}s")

def main():
    config = Configuration()
    config.host = "https://api.mypurecloud.com"
    config.oauth_client_id = os.getenv("GENESYS_CLIENT_ID")
    config.oauth_client_secret = os.getenv("GENESYS_CLIENT_SECRET")
    config.oauth_private_key = os.getenv("GENESYS_PRIVATE_KEY")
    config.oauth_private_key_password = os.getenv("GENESYS_PRIVATE_KEY_PASSWORD")
    config.oauth_jwt_grant_type = "urn:ietf:params:oauth:grant-type:jwt-bearer"
    
    aggregator = CdrAggregator(
        config=config,
        tariff_url=os.getenv("TARIFF_SERVICE_URL", "https://billing.internal"),
        webhook_url=os.getenv("ERP_WEBHOOK_URL", "https://erp.internal/api/v1/invoices/trigger")
    )
    
    aggregator.run(
        start_time="2024-01-01T00:00:00Z",
        end_time="2024-01-31T23:59:59Z",
        batch_size=500
    )

if __name__ == "__main__":
    main()

Common Errors & Debugging

Error: 401 Unauthorized

• Cause: The OAuth private key is expired, malformed, or the client credentials lack the telephony:call:read scope.
• Fix: Regenerate the private key in the Genesys Cloud admin console. Verify the scope assignment on the OAuth client. Ensure the private key password matches the key file.
• Code Fix: The SDK raises httpx.HTTPStatusError with status 401. Catch it explicitly and log the credential validation failure before terminating the process.

Error: 429 Too Many Requests

• Cause: The aggregation loop exceeds Genesys Cloud API rate limits. The Telephony API enforces per-client and per-tenant quotas.
• Fix: Implement exponential backoff. Read the Retry-After header from the response. The provided code already includes a retry loop that sleeps for the specified duration.
• Code Fix:

except httpx.HTTPStatusError as e:
    if e.response.status_code == 429:
        retry_after = int(e.response.headers.get("Retry-After", 2))
        time.sleep(retry_after)
        continue

Error: 500 Internal Server Error

• Cause: The Genesys Cloud query engine encounters a malformed date range, unsupported filter operator, or backend timeout.
• Fix: Validate the ISO 8601 date strings before submission. Ensure the op field uses valid operators (between, gt, lt). Reduce the date window size if timeouts persist.
• Code Fix: Wrap the API call in a try-except block that logs the request payload and raises a custom exception with context for downstream monitoring systems.

Official References

• Genesys Cloud Telephony CDR Query API
• Genesys Cloud Python SDK Documentation
• OAuth 2.0 JWT Bearer Grant Type
• Pydantic Validation Schema
• HTTPX Client Library