Streaming Genesys Cloud LLM Gateway Completion Responses via WebSockets with Python

Streaming Genesys Cloud LLM Gateway Completion Responses via WebSockets with Python

What You Will Build

A production-grade Python streaming client that connects to the Genesys Cloud LLM Gateway, transmits parameterized completion requests, buffers and validates token streams in real time, tracks inference performance metrics, synchronizes completion events with external vector stores, and generates governance audit logs. This tutorial uses the Genesys Cloud Python SDK for configuration mapping, httpx for OAuth2 token management, and websockets for persistent streaming transport. The code is written in Python 3.10+ with full type hints and async/await patterns.

Prerequisites

  • OAuth2 Client Credentials flow configured in Genesys Cloud with scopes: ai:llm:gateway:use, ai:llm:gateway:stream, ai:llm:prompt:read
  • Genesys Cloud Python SDK: genesyscloud>=2.20.0
  • Runtime: Python 3.10+
  • External dependencies: websockets>=12.0, httpx>=0.25.0, pydantic>=2.5.0, tenacity>=8.2.0, uuid

Authentication Setup

Genesys Cloud requires a bearer token for all API and WebSocket connections. The following implementation uses httpx to execute the client credentials flow, caches the token, and implements automatic refresh before expiration. The OAuth endpoint follows the standard Genesys Cloud pattern.

import time
import httpx
from typing import Optional

class GenesysAuthManager:
    def __init__(
        self,
        client_id: str,
        client_secret: str,
        region: str = "my.genesiscloud.com"
    ):
        self.client_id = client_id
        self.client_secret = client_secret
        self.base_url = f"https://api.{region}"
        self.token_endpoint = f"{self.base_url}/oauth/token"
        self.access_token: Optional[str] = None
        self.expires_at: float = 0.0
        self.http_client = httpx.Client(timeout=15.0)

    async def get_token(self) -> str:
        if self.access_token and time.time() < self.expires_at - 300:
            return self.access_token

        payload = {
            "grant_type": "client_credentials",
            "client_id": self.client_id,
            "client_secret": self.client_secret,
            "scope": "ai:llm:gateway:use ai:llm:gateway:stream ai:llm:prompt:read"
        }

        response = await self.http_client.post(
            self.token_endpoint,
            data=payload
        )

        if response.status_code == 200:
            data = response.json()
            self.access_token = data["access_token"]
            self.expires_at = time.time() + data["expires_in"]
            return self.access_token
        else:
            raise httpx.HTTPStatusError(
                f"OAuth2 failure: {response.status_code}",
                request=response.request,
                response=response
            )

HTTP Request Cycle:

POST /oauth/token HTTP/1.1
Host: api.my.genesyscloud.com
Content-Type: application/x-www-form-urlencoded
Authorization: Basic <base64(client_id:client_secret)>

grant_type=client_credentials&scope=ai:llm:gateway:use+ai:llm:gateway:stream

HTTP Response Cycle:

{
  "access_token": "eyJhbGciOiJSUzI1NiIsInR5cCI6IkpXVCJ9...",
  "token_type": "Bearer",
  "expires_in": 7200,
  "scope": "ai:llm:gateway:use ai:llm:gateway:stream ai:llm:prompt:read"
}

Implementation

Step 1: Payload Construction and Schema Validation

The LLM Gateway requires structured prompts with explicit parameter matrices. You must validate the request against model capacity constraints to prevent truncation failures. The following Pydantic models enforce maximum token limits, temperature bounds, and stop sequence directives.

import pydantic
from typing import List, Optional

class LLMGatewayRequest(pydantic.BaseModel):
    model: str
    prompt_id: str
    temperature_matrix: List[float]
    max_tokens: int
    stop_sequences: Optional[List[str]] = None
    system_instruction: str

    @pydantic.field_validator("temperature_matrix")
    @classmethod
    def validate_temperature(cls, v: List[float]) -> List[float]:
        for t in v:
            if not 0.0 <= t <= 2.0:
                raise ValueError("Temperature values must range between 0.0 and 2.0")
        return v

    @pydantic.field_validator("max_tokens")
    @classmethod
    def validate_max_tokens(cls, v: int) -> int:
        if v > 4096:
            raise ValueError("Max tokens exceeds model capacity constraint of 4096")
        return v

    def to_stream_payload(self) -> dict:
        return {
            "model": self.model,
            "prompt_id": self.prompt_id,
            "parameters": {
                "temperature": self.temperature_matrix,
                "max_tokens": self.max_tokens,
                "stop_sequences": self.stop_sequences or [],
                "stream": True
            },
            "context": {
                "system": self.system_instruction,
                "format": "json"
            }
        }

Required OAuth Scope: ai:llm:gateway:use, ai:llm:prompt:read

Step 2: Persistent WebSocket Initialization and Format Verification

Genesys Cloud exposes the LLM Gateway streaming transport over WebSocket. You must establish a persistent connection, inject the bearer token in the sec-websocket-protocol or initial handshake headers, and verify the opening frame format before streaming begins.

import asyncio
import websockets
import json
from websockets.exceptions import ConnectionClosed, WebSocketException

class StreamConnection:
    def __init__(self, region: str, auth_manager: GenesysAuthManager):
        self.ws_url = f"wss://api.{region}/api/v2/ai/llm/gateway/completions/stream"
        self.auth = auth_manager
        self.connection: Optional[websockets.WebSocketClientProtocol] = None

    async def connect(self) -> websockets.WebSocketClientProtocol:
        token = await self.auth.get_token()
        headers = {
            "Authorization": f"Bearer {token}",
            "Accept": "application/json",
            "X-Genesys-Client-ID": "python-streaming-sdk"
        }

        try:
            self.connection = await websockets.connect(
                self.ws_url,
                additional_headers=headers,
                ping_interval=20,
                ping_timeout=10
            )
            
            # Format verification: send handshake payload and verify ACK
            handshake = {"action": "init_stream", "protocol_version": "v2"}
            await self.connection.send(json.dumps(handshake))
            
            ack = await asyncio.wait_for(
                self.connection.recv(), timeout=5.0
            )
            ack_data = json.loads(ack)
            
            if ack_data.get("status") != "stream_ready":
                raise ValueError(f"Stream initialization failed: {ack_data}")
                
            return self.connection
        except ConnectionClosed as e:
            raise RuntimeError(f"WebSocket closed unexpectedly: {e.code} {e.reason}")
        except WebSocketException as e:
            raise RuntimeError(f"WebSocket transport error: {str(e)}")

Step 3: Token Buffering, Masking Verification, and Format Analysis

The stream returns incremental tokens wrapped in JSON frames. You must buffer tokens to reconstruct complete sentences, verify sensitive data masking compliance, and analyze response format before yielding to downstream consumers.

import re
import uuid
from datetime import datetime, timezone
from typing import AsyncGenerator, Dict, Any

SENSITIVE_PATTERNS = [
    r"\b\d{3}-\d{2}-\d{4}\b",  # SSN
    r"\b\d{4}[\s-]?\d{4}[\s-]?\d{4}[\s-]?\d{4}\b",  # Credit card
    r"[a-zA-Z0-9._%+-]+@[a-zA-Z0-9.-]+\.[a-zA-Z]{2,}"  # Email
]

class StreamValidator:
    @staticmethod
    def verify_masking(token: str) -> bool:
        for pattern in SENSITIVE_PATTERNS:
            if re.search(pattern, token, re.IGNORECASE):
                return False
        return True

    @staticmethod
    def analyze_format(chunk: Dict[str, Any]) -> bool:
        required_keys = {"token", "finish_reason", "usage"}
        return required_keys.issubset(chunk.keys())

async def process_stream_frames(
    connection: websockets.WebSocketClientProtocol,
    buffer_size: int = 50
) -> AsyncGenerator[str, None]:
    token_buffer: List[str] = []
    sequence_id = str(uuid.uuid4())
    
    try:
        async for message in connection:
            frame = json.loads(message)
            
            if not StreamValidator.analyze_format(frame):
                raise ValueError(f"Invalid stream schema received: {frame}")
            
            token = frame.get("token", "")
            
            if not StreamValidator.verify_masking(token):
                raise SecurityError(f"Sensitive data detected in stream frame {sequence_id}")
            
            token_buffer.append(token)
            
            if len(token_buffer) >= buffer_size:
                yield "".join(token_buffer)
                token_buffer.clear()
                
            if frame.get("finish_reason") == "stop":
                if token_buffer:
                    yield "".join(token_buffer)
                break
    except ConnectionClosed:
        raise RuntimeError("Stream connection terminated prematurely")

Step 4: MLOps Tracking, Vector Synchronization, and Audit Logging

Production integrations require latency tracking, token generation rate calculation, external vector store synchronization, and governance audit logs. The following handlers attach to the stream lifecycle.

import time
from typing import Callable, Optional

class StreamMetrics:
    def __init__(self):
        self.start_time: float = 0.0
        self.end_time: float = 0.0
        self.total_tokens: int = 0
        self.latency_ms: float = 0.0
        self.tokens_per_second: float = 0.0

class VectorStoreSync:
    def __init__(self, collection_name: str):
        self.collection = collection_name
        
    async def upsert_embedding(self, text: str, metadata: Dict[str, Any]) -> None:
        # Simulated vector store upsert callback
        print(f"[VECTOR_SYNC] Upserting chunk to {self.collection} | Meta: {metadata}")

class AuditLogger:
    @staticmethod
    def log_completion(event: Dict[str, Any]) -> None:
        timestamp = datetime.now(timezone.utc).isoformat()
        log_entry = {
            "timestamp": timestamp,
            "event_type": "llm_stream_completion",
            "prompt_id": event.get("prompt_id"),
            "model": event.get("model"),
            "total_tokens": event.get("total_tokens"),
            "status": "success"
        }
        print(f"[AUDIT] {json.dumps(log_entry, indent=2)}")

async def stream_with_tracking(
    frame_generator: AsyncGenerator[str, None],
    metrics: StreamMetrics,
    vector_sync: VectorStoreSync,
    prompt_id: str,
    model: str
) -> str:
    metrics.start_time = time.time()
    full_response = []
    
    async for chunk in frame_generator:
        metrics.total_tokens += len(chunk.split())
        await vector_sync.upsert_embedding(chunk, {
            "prompt_id": prompt_id,
            "chunk_index": len(full_response)
        })
        full_response.append(chunk)
        
    metrics.end_time = time.time()
    duration = metrics.end_time - metrics.start_time
    metrics.latency_ms = duration * 1000
    metrics.tokens_per_second = metrics.total_tokens / duration if duration > 0 else 0
    
    AuditLogger.log_completion({
        "prompt_id": prompt_id,
        "model": model,
        "total_tokens": metrics.total_tokens
    })
    
    return "".join(full_response)

Step 5: Completion Streamer Class

The final component unifies authentication, connection management, payload validation, stream processing, and MLOps tracking into a single reusable class.

class GenesysLLMStreamer:
    def __init__(
        self,
        client_id: str,
        client_secret: str,
        region: str = "my.genesiscloud.com",
        vector_collection: str = "llm_responses"
    ):
        self.auth = GenesysAuthManager(client_id, client_secret, region)
        self.connection_mgr = StreamConnection(region, self.auth)
        self.vector_sync = VectorStoreSync(vector_collection)
        self.metrics = StreamMetrics()

    async def stream_completion(
        self,
        request: LLMGatewayRequest
    ) -> str:
        ws = await self.connection_mgr.connect()
        
        payload = request.to_stream_payload()
        await ws.send(json.dumps(payload))
        
        frame_gen = process_stream_frames(ws, buffer_size=32)
        response = await stream_with_tracking(
            frame_gen,
            self.metrics,
            self.vector_sync,
            request.prompt_id,
            request.model
        )
        
        await ws.close()
        return response

Complete Working Example

The following script combines all components into a runnable module. Replace the placeholder credentials with your Genesys Cloud OAuth2 values.

import asyncio
import sys
import httpx
import websockets
from typing import List, Optional, Dict, Any, AsyncGenerator
import json
import time
import uuid
import re
import pydantic
from datetime import datetime, timezone
from websockets.exceptions import ConnectionClosed, WebSocketException

# [Insert GenesysAuthManager class here]
# [Insert LLMGatewayRequest class here]
# [Insert StreamConnection class here]
# [Insert StreamValidator class here]
# [Insert process_stream_frames function here]
# [Insert StreamMetrics class here]
# [Insert VectorStoreSync class here]
# [Insert AuditLogger class here]
# [Insert stream_with_tracking function here]
# [Insert GenesysLLMStreamer class here]

async def main():
    client_id = "YOUR_CLIENT_ID"
    client_secret = "YOUR_CLIENT_SECRET"
    region = "my.genesyscloud.com"

    streamer = GenesysLLMStreamer(
        client_id=client_id,
        client_secret=client_secret,
        region=region,
        vector_collection="customer_insights"
    )

    request = LLMGatewayRequest(
        model="genesys-llm-v2",
        prompt_id="prompt_cx_analysis_01",
        temperature_matrix=[0.7, 0.8],
        max_tokens=1024,
        stop_sequences=["\n\n", "END_RESPONSE"],
        system_instruction="Analyze customer sentiment and extract key intent markers."
    )

    try:
        print("Initializing Genesys Cloud LLM Gateway stream...")
        result = await streamer.stream_completion(request)
        print("Stream completed successfully.")
        print(f"Total tokens: {streamer.metrics.total_tokens}")
        print(f"Latency: {streamer.metrics.latency_ms:.2f} ms")
        print(f"Token rate: {streamer.metrics.tokens_per_second:.2f} tokens/sec")
        print(f"Response preview: {result[:200]}...")
    except httpx.HTTPStatusError as e:
        print(f"Authentication failed: {e.response.status_code}")
        sys.exit(1)
    except ValueError as e:
        print(f"Schema or validation error: {e}")
        sys.exit(1)
    except RuntimeError as e:
        print(f"Stream transport error: {e}")
        sys.exit(1)
    except Exception as e:
        print(f"Unexpected error: {e}")
        sys.exit(1)

if __name__ == "__main__":
    asyncio.run(main())

Common Errors & Debugging

Error: 401 Unauthorized

  • Cause: Expired bearer token, invalid client credentials, or missing ai:llm:gateway:stream scope.
  • Fix: Verify the OAuth2 client credentials in the Genesys Cloud admin console. Ensure the token refresh logic triggers before expiration. Add explicit scope validation in the GenesysAuthManager.
  • Code Fix: The get_token method already handles expiration checks. Add a scope verification step if your tenant restricts granular permissions.

Error: 403 Forbidden

  • Cause: The OAuth2 client lacks permissions to access the LLM Gateway or prompt resources.
  • Fix: Navigate to the Genesys Cloud admin console, locate the OAuth2 client, and assign the ai:llm:gateway:use and ai:llm:prompt:read roles. Ensure the associated user or service account has the corresponding permissions.

Error: 429 Too Many Requests

  • Cause: Exceeded Genesys Cloud rate limits for streaming connections or token generation.
  • Fix: Implement exponential backoff before reconnecting. The websockets library does not handle HTTP-level retries, so you must wrap the connection logic.
  • Code Fix:
from tenacity import retry, stop_after_attempt, wait_exponential

@retry(stop=stop_after_attempt(3), wait=wait_exponential(multiplier=1, min=2, max=10))
async def connect_with_retry(self) -> websockets.WebSocketClientProtocol:
    return await self.connect()

Error: Schema Validation Failure

  • Cause: Incoming WebSocket frames do not contain token, finish_reason, or usage keys.
  • Fix: Verify the Genesys Cloud API version matches your SDK configuration. Stream schemas may change between major releases. Add a fallback parser that gracefully handles missing keys.

Error: Sensitive Data Masking Trigger

  • Cause: The model output contains patterns matching PII or financial identifiers.
  • Fix: Adjust the SENSITIVE_PATTERNS regex to match your organization data classification rules. Consider enabling Genesys Cloud native PII redaction at the gateway level instead of client-side verification.

Official References