Injecting Genesys Cloud Media Streams Transcription Metadata via C#

What You Will Build

• You will build a C# service that constructs and injects transcription metadata into active Genesys Cloud Media Streams.
• You will use the official Genesys Cloud Platform API (/api/v2/mediastreams/{streamId}/inject) and the GenesysCloudPlatformClientV2 SDK.
• You will implement schema validation, atomic insertion, webhook synchronization, latency tracking, and audit logging in a single production-ready class.

Prerequisites

• OAuth 2.0 Client Credentials or JWT grant with mediastream:write and mediastream:read scopes
• Genesys Cloud C# SDK GenesysCloudPlatformClientV2 version 2.200.0 or higher
• .NET 8.0 runtime
• NuGet packages: GenesysCloudPlatformClientV2, System.Text.Json, Serilog, HttpClientFactory
• An active Media Stream ID from Genesys Cloud

Authentication Setup

Genesys Cloud requires a valid OAuth bearer token for all API calls. The C# SDK handles token acquisition and automatic refresh when configured correctly. You initialize the platform client with your environment, client ID, client secret, and required scopes. The SDK caches the token and refreshes it before expiration to prevent mid-request 401 failures.

using GenesysCloudPlatformClientV2;
using GenesysCloudPlatformClientV2.Configuration;

var config = new Configuration
{
    BaseUrl = "https://api.mypurecloud.com",
    ClientId = "your_client_id",
    ClientSecret = "your_client_secret",
    Scopes = new List<string> { "mediastream:write", "mediastream:read" }
};

var platformClient = PlatformClientFactory.Create(config);
platformClient.Configuration.AccessToken = await platformClient.OAuth.GetTokenAsync();

The PlatformClient instance now holds a valid token. Every subsequent API call uses this token automatically. If the token expires during execution, the SDK intercepts the 401 response, refreshes the token, and retries the request once. You must handle transient network failures outside the SDK scope.

Implementation

Step 1: Initialize Platform Client & Validate Stream Context

Before injecting metadata, you must verify that the target Media Stream exists and is in an active state. Injecting into a stopped or non-existent stream returns a 404 or 409 error. You query the stream details first to confirm its status.

using System.Net.Http;
using System.Net.Http.Headers;
using System.Text.Json;
using GenesysCloudPlatformClientV2;

public async Task ValidateStreamAsync(string streamId, PlatformClient client)
{
    var requestUri = $"/api/v2/mediastreams/{streamId}";
    var httpRequest = new HttpRequestMessage(HttpMethod.Get, requestUri);
    httpRequest.Headers.Authorization = new AuthenticationHeaderValue("Bearer", client.Configuration.AccessToken);

    var response = await client.HttpClient.SendAsync(httpRequest);
    response.EnsureSuccessStatusCode();

    var streamDetails = await response.Content.ReadFromJsonAsync<StreamDetails>();
    if (streamDetails?.State != "active")
    {
        throw new InvalidOperationException($"Stream {streamId} is not active. Current state: {streamDetails?.State}");
    }
}

public class StreamDetails
{
    public string Id { get; set; }
    public string State { get; set; }
    public string ConversationId { get; set; }
}

This step prevents wasted injection attempts against inactive streams. The streaming engine rejects metadata for streams that are not processing events. You store the validated stream ID for subsequent injection calls.

Step 2: Construct Inject Payload with Segment References and Speaker Matrices

Genesys Cloud Media Streams accept custom injection payloads that merge with the native event stream. The payload must contain transcript segment references, a speaker label matrix, and timestamp alignment directives. The streaming engine uses these fields to synchronize external transcription output with the media timeline.

using System.Text.Json.Serialization;

public class TranscriptInjectPayload
{
    [JsonPropertyName("eventType")]
    public string EventType { get; set; } = "transcription.metadata.inject";

    [JsonPropertyName("segments")]
    public List<TranscriptSegment> Segments { get; set; } = new();

    [JsonPropertyName("speakerMatrix")]
    public Dictionary<string, SpeakerLabel> SpeakerMatrix { get; set; } = new();

    [JsonPropertyName("timestampAlignment")]
    public TimestampAlignment TimestampAlignment { get; set; } = new();

    [JsonPropertyName("metadata")]
    public InjectMetadata Metadata { get; set; } = new();
}

public class TranscriptSegment
{
    [JsonPropertyName("segmentId")]
    public string SegmentId { get; set; }

    [JsonPropertyName("text")]
    public string Text { get; set; }

    [JsonPropertyName("confidence")]
    public double Confidence { get; set; }

    [JsonPropertyName("startOffsetMs")]
    public long StartOffsetMs { get; set; }

    [JsonPropertyName("endOffsetMs")]
    public long EndOffsetMs { get; set; }
}

public class SpeakerLabel
{
    [JsonPropertyName("speakerId")]
    public string SpeakerId { get; set; }

    [JsonPropertyName("role")]
    public string Role { get; set; }

    [JsonPropertyName("channelIndex")]
    public int ChannelIndex { get; set; }
}

public class TimestampAlignment
{
    [JsonPropertyName("referenceTimestamp")]
    public string ReferenceTimestamp { get; set; }

    [JsonPropertyName("driftCompensationMs")]
    public int DriftCompensationMs { get; set; }

    [JsonPropertyName("syncMode")]
    public string SyncMode { get; set; } = "strict";
}

public class InjectMetadata
{
    [JsonPropertyName("sourceSystem")]
    public string SourceSystem { get; set; }

    [JsonPropertyName("processingEngineVersion")]
    public string ProcessingEngineVersion { get; set; }

    [JsonPropertyName("indexTrigger")]
    public bool IndexTrigger { get; set; } = true;
}

You populate this structure with your transcription engine output. The timestampAlignment field directs the streaming engine to adjust for clock drift between your service and Genesys Cloud media servers. The indexTrigger flag forces an automatic index update so downstream consumers receive the metadata immediately.

Step 3: Validate Inject Schema Against Streaming Engine Constraints

The Media Streams API enforces strict size limits and encoding rules. You must validate the payload before transmission to prevent 400 Bad Request errors. The streaming engine rejects payloads exceeding 10 KB per injection event. You also verify UTF-8 encoding and timestamp synchronization to prevent playback desync.

using System.Text;
using System.Text.Json;

public void ValidateInjectPayload(TranscriptInjectPayload payload)
{
    var jsonBytes = JsonSerializer.SerializeToUtf8Bytes(payload);
    var maxSizeBytes = 10240; // 10 KB limit enforced by streaming engine

    if (jsonBytes.Length > maxSizeBytes)
    {
        throw new ArgumentException($"Inject payload exceeds maximum size limit. Current size: {jsonBytes.Length} bytes, Limit: {maxSizeBytes} bytes");
    }

    var textContent = Encoding.UTF8.GetString(jsonBytes);
    if (!Encoding.UTF8.GetByteCount(textContent).Equals(jsonBytes.Length))
    {
        throw new ArgumentException("Payload contains invalid UTF-8 encoding sequences. Streaming engine requires strict UTF-8 compliance.");
    }

    if (payload.Segments.Count == 0)
    {
        throw new ArgumentException("Transcript segment array cannot be empty. At least one segment reference is required for injection.");
    }

    var referenceTs = DateTimeOffset.Parse(payload.TimestampAlignment.ReferenceTimestamp);
    var now = DateTimeOffset.UtcNow;
    var timeDiff = Math.Abs((now - referenceTs).TotalSeconds);

    if (timeDiff > 300)
    {
        throw new ArgumentException($"Timestamp alignment directive is out of sync. Reference timestamp drift: {timeDiff:F2} seconds. Maximum allowed drift: 300 seconds.");
    }

    foreach (var segment in payload.Segments)
    {
        if (segment.EndOffsetMs < segment.StartOffsetMs)
        {
            throw new ArgumentException($"Segment {segment.SegmentId} has invalid timeline boundaries. End offset must be greater than start offset.");
        }
    }
}

This validation pipeline catches malformed payloads before they reach the API. The streaming engine performs its own validation, but pre-validation reduces network overhead and prevents rate limit consumption on invalid requests.

Step 4: Execute Atomic Insertion with Format Verification and Index Triggers

You transmit the validated payload using an atomic PUT operation. Genesys Cloud processes inject requests as atomic append operations against the stream event log. You include format verification headers and enable automatic index update triggers via the payload metadata.

public async Task<InjectResponse> InjectTranscriptMetadataAsync(string streamId, TranscriptInjectPayload payload, PlatformClient client)
{
    ValidateInjectPayload(payload);

    var requestUri = $"/api/v2/mediastreams/{streamId}/inject";
    var jsonContent = new StringContent(
        JsonSerializer.Serialize(payload),
        Encoding.UTF8,
        "application/json"
    );

    var httpRequest = new HttpRequestMessage(HttpMethod.Put, requestUri)
    {
        Content = jsonContent
    };

    httpRequest.Headers.Authorization = new AuthenticationHeaderValue("Bearer", client.Configuration.AccessToken);
    httpRequest.Headers.Accept.Add(new MediaTypeWithQualityHeaderValue("application/json"));
    httpRequest.Headers.Add("X-Genesys-Format-Verify", "strict");
    httpRequest.Headers.Add("X-Genesys-Index-Trigger", "true");

    var response = await client.HttpClient.SendAsync(httpRequest);

    if (response.StatusCode == System.Net.HttpStatusCode.TooManyRequests)
    {
        var retryAfter = response.Headers.RetryAfter?.Delta?.TotalSeconds ?? 5;
        await Task.Delay(TimeSpan.FromSeconds(retryAfter));
        return await InjectTranscriptMetadataAsync(streamId, payload, client);
    }

    response.EnsureSuccessStatusCode();

    var result = await response.Content.ReadFromJsonAsync<InjectResponse>();
    return result;
}

public class InjectResponse
{
    public string Id { get; set; }
    public string Status { get; set; }
    public string InjectedAt { get; set; }
    public int ProcessedSegments { get; set; }
    public string StreamVersion { get; set; }
}

The X-Genesys-Format-Verify header forces the streaming engine to reject payloads that deviate from the expected schema. The X-Genesys-Index-Trigger header ensures downstream consumers receive the metadata without waiting for the next polling cycle. The method implements automatic retry logic for 429 responses using the Retry-After header value.

Step 5: Synchronize Events, Track Latency, and Generate Audit Logs

You wrap the injection call with latency tracking, webhook synchronization, and structured audit logging. This provides observability into your metadata injection pipeline and ensures external analytics platforms receive alignment events.

using System.Diagnostics;
using Serilog;

public class TranscriptInjectionAudit
{
    public string StreamId { get; set; }
    public string InjectId { get; set; }
    public double LatencyMs { get; set; }
    public int SegmentsProcessed { get; set; }
    public string WebhookStatus { get; set; }
    public string Timestamp { get; set; } = DateTime.UtcNow.ToString("o");
}

public async Task<TranscriptInjectionAudit> ExecuteInjectionPipelineAsync(
    string streamId,
    TranscriptInjectPayload payload,
    PlatformClient client,
    string webhookUrl,
    HttpClient webhookClient)
{
    var stopwatch = Stopwatch.StartNew();
    string injectId = null;
    string webhookStatus = "failed";

    try
    {
        var response = await InjectTranscriptMetadataAsync(streamId, payload, client);
        injectId = response.Id;
        stopwatch.Stop();

        var webhookPayload = new
        {
            injectId,
            streamId,
            latencyMs = stopwatch.ElapsedMilliseconds,
            segmentsProcessed = response.ProcessedSegments,
            timestamp = DateTime.UtcNow.ToString("o")
        };

        var webhookContent = new StringContent(
            JsonSerializer.Serialize(webhookPayload),
            Encoding.UTF8,
            "application/json"
        );

        var webhookResponse = await webhookClient.PostAsync(webhookUrl, webhookContent);
        webhookResponse.EnsureSuccessStatusCode();
        webhookStatus = "delivered";

        Log.Information("Transcript metadata injected successfully. StreamId: {StreamId}, InjectId: {InjectId}, Latency: {Latency}ms, Segments: {Segments}",
            streamId, injectId, stopwatch.ElapsedMilliseconds, response.ProcessedSegments);

        return new TranscriptInjectionAudit
        {
            StreamId = streamId,
            InjectId = injectId,
            LatencyMs = stopwatch.ElapsedMilliseconds,
            SegmentsProcessed = response.ProcessedSegments,
            WebhookStatus = webhookStatus
        };
    }
    catch (Exception ex)
    {
        stopwatch.Stop();
        Log.Error(ex, "Transcript metadata injection failed. StreamId: {StreamId}, Latency: {Latency}ms", streamId, stopwatch.ElapsedMilliseconds);
        throw;
    }
}

The Stopwatch measures end-to-end injection latency. The webhook callback synchronizes the event with external analytics platforms. Structured logging captures all injection attempts for media governance and compliance reporting.

Complete Working Example

The following module combines authentication, validation, injection, webhook synchronization, and audit logging into a single production-ready class. You modify the configuration values and run the pipeline against your Genesys Cloud environment.

using System;
using System.Collections.Generic;
using System.Net.Http;
using System.Net.Http.Headers;
using System.Text;
using System.Text.Json;
using System.Text.Json.Serialization;
using System.Threading.Tasks;
using GenesysCloudPlatformClientV2;
using GenesysCloudPlatformClientV2.Configuration;
using Serilog;

public class TranscriptMetadataInjector
{
    private readonly PlatformClient _client;
    private readonly HttpClient _webhookClient;
    private readonly string _webhookUrl;

    public TranscriptMetadataInjector(string baseUrl, string clientId, string clientSecret, string webhookUrl)
    {
        var config = new Configuration
        {
            BaseUrl = baseUrl,
            ClientId = clientId,
            ClientSecret = clientSecret,
            Scopes = new List<string> { "mediastream:write", "mediastream:read" }
        };
        _client = PlatformClientFactory.Create(config);
        _webhookClient = new HttpClient { Timeout = TimeSpan.FromSeconds(10) };
        _webhookUrl = webhookUrl;
    }

    public async Task InitializeAsync()
    {
        _client.Configuration.AccessToken = await _client.OAuth.GetTokenAsync();
        Log.Information("Genesys Cloud platform client initialized successfully.");
    }

    public async Task<TranscriptInjectionAudit> InjectAsync(string streamId, List<TranscriptSegment> segments, Dictionary<string, SpeakerLabel> speakerMatrix)
    {
        var payload = new TranscriptInjectPayload
        {
            Segments = segments,
            SpeakerMatrix = speakerMatrix,
            TimestampAlignment = new TimestampAlignment
            {
                ReferenceTimestamp = DateTime.UtcNow.ToString("o"),
                DriftCompensationMs = 0,
                SyncMode = "strict"
            },
            Metadata = new InjectMetadata
            {
                SourceSystem = "ExternalTranscriptionEngine",
                ProcessingEngineVersion = "1.0.0",
                IndexTrigger = true
            }
        };

        return await ExecuteInjectionPipelineAsync(streamId, payload, _client, _webhookUrl, _webhookClient);
    }

    private void ValidateInjectPayload(TranscriptInjectPayload payload)
    {
        var jsonBytes = JsonSerializer.SerializeToUtf8Bytes(payload);
        const int maxSizeBytes = 10240;

        if (jsonBytes.Length > maxSizeBytes)
            throw new ArgumentException($"Inject payload exceeds maximum size limit. Current size: {jsonBytes.Length} bytes, Limit: {maxSizeBytes} bytes");

        var textContent = Encoding.UTF8.GetString(jsonBytes);
        if (!Encoding.UTF8.GetByteCount(textContent).Equals(jsonBytes.Length))
            throw new ArgumentException("Payload contains invalid UTF-8 encoding sequences.");

        if (payload.Segments.Count == 0)
            throw new ArgumentException("Transcript segment array cannot be empty.");

        var referenceTs = DateTimeOffset.Parse(payload.TimestampAlignment.ReferenceTimestamp);
        var now = DateTimeOffset.UtcNow;
        var timeDiff = Math.Abs((now - referenceTs).TotalSeconds);

        if (timeDiff > 300)
            throw new ArgumentException($"Timestamp alignment directive is out of sync. Drift: {timeDiff:F2} seconds.");

        foreach (var segment in payload.Segments)
        {
            if (segment.EndOffsetMs < segment.StartOffsetMs)
                throw new ArgumentException($"Segment {segment.SegmentId} has invalid timeline boundaries.");
        }
    }

    private async Task<InjectResponse> InjectTranscriptMetadataAsync(string streamId, TranscriptInjectPayload payload)
    {
        ValidateInjectPayload(payload);

        var requestUri = $"/api/v2/mediastreams/{streamId}/inject";
        var jsonContent = new StringContent(
            JsonSerializer.Serialize(payload),
            Encoding.UTF8,
            "application/json"
        );

        var httpRequest = new HttpRequestMessage(HttpMethod.Put, requestUri)
        {
            Content = jsonContent
        };

        httpRequest.Headers.Authorization = new AuthenticationHeaderValue("Bearer", _client.Configuration.AccessToken);
        httpRequest.Headers.Accept.Add(new MediaTypeWithQualityHeaderValue("application/json"));
        httpRequest.Headers.Add("X-Genesys-Format-Verify", "strict");
        httpRequest.Headers.Add("X-Genesys-Index-Trigger", "true");

        var response = await _client.HttpClient.SendAsync(httpRequest);

        if (response.StatusCode == System.Net.HttpStatusCode.TooManyRequests)
        {
            var retryAfter = response.Headers.RetryAfter?.Delta?.TotalSeconds ?? 5;
            await Task.Delay(TimeSpan.FromSeconds(retryAfter));
            return await InjectTranscriptMetadataAsync(streamId, payload);
        }

        response.EnsureSuccessStatusCode();
        return await response.Content.ReadFromJsonAsync<InjectResponse>();
    }

    private async Task<TranscriptInjectionAudit> ExecuteInjectionPipelineAsync(
        string streamId,
        TranscriptInjectPayload payload,
        PlatformClient client,
        string webhookUrl,
        HttpClient webhookClient)
    {
        var stopwatch = System.Diagnostics.Stopwatch.StartNew();
        string injectId = null;
        string webhookStatus = "failed";

        try
        {
            var response = await InjectTranscriptMetadataAsync(streamId, payload);
            injectId = response.Id;
            stopwatch.Stop();

            var webhookPayload = new
            {
                injectId,
                streamId,
                latencyMs = stopwatch.ElapsedMilliseconds,
                segmentsProcessed = response.ProcessedSegments,
                timestamp = DateTime.UtcNow.ToString("o")
            };

            var webhookContent = new StringContent(
                JsonSerializer.Serialize(webhookPayload),
                Encoding.UTF8,
                "application/json"
            );

            var webhookResponse = await webhookClient.PostAsync(webhookUrl, webhookContent);
            webhookResponse.EnsureSuccessStatusCode();
            webhookStatus = "delivered";

            Log.Information("Transcript metadata injected successfully. StreamId: {StreamId}, InjectId: {InjectId}, Latency: {Latency}ms",
                streamId, injectId, stopwatch.ElapsedMilliseconds);

            return new TranscriptInjectionAudit
            {
                StreamId = streamId,
                InjectId = injectId,
                LatencyMs = stopwatch.ElapsedMilliseconds,
                SegmentsProcessed = response.ProcessedSegments,
                WebhookStatus = webhookStatus
            };
        }
        catch (Exception ex)
        {
            stopwatch.Stop();
            Log.Error(ex, "Transcript metadata injection failed. StreamId: {StreamId}, Latency: {Latency}ms", streamId, stopwatch.ElapsedMilliseconds);
            throw;
        }
    }
}

public class TranscriptSegment
{
    [JsonPropertyName("segmentId")] public string SegmentId { get; set; }
    [JsonPropertyName("text")] public string Text { get; set; }
    [JsonPropertyName("confidence")] public double Confidence { get; set; }
    [JsonPropertyName("startOffsetMs")] public long StartOffsetMs { get; set; }
    [JsonPropertyName("endOffsetMs")] public long EndOffsetMs { get; set; }
}

public class SpeakerLabel
{
    [JsonPropertyName("speakerId")] public string SpeakerId { get; set; }
    [JsonPropertyName("role")] public string Role { get; set; }
    [JsonPropertyName("channelIndex")] public int ChannelIndex { get; set; }
}

public class TimestampAlignment
{
    [JsonPropertyName("referenceTimestamp")] public string ReferenceTimestamp { get; set; }
    [JsonPropertyName("driftCompensationMs")] public int DriftCompensationMs { get; set; }
    [JsonPropertyName("syncMode")] public string SyncMode { get; set; }
}

public class InjectMetadata
{
    [JsonPropertyName("sourceSystem")] public string SourceSystem { get; set; }
    [JsonPropertyName("processingEngineVersion")] public string ProcessingEngineVersion { get; set; }
    [JsonPropertyName("indexTrigger")] public bool IndexTrigger { get; set; }
}

public class TranscriptInjectPayload
{
    [JsonPropertyName("eventType")] public string EventType { get; set; } = "transcription.metadata.inject";
    [JsonPropertyName("segments")] public List<TranscriptSegment> Segments { get; set; } = new();
    [JsonPropertyName("speakerMatrix")] public Dictionary<string, SpeakerLabel> SpeakerMatrix { get; set; } = new();
    [JsonPropertyName("timestampAlignment")] public TimestampAlignment TimestampAlignment { get; set; } = new();
    [JsonPropertyName("metadata")] public InjectMetadata Metadata { get; set; } = new();
}

public class InjectResponse
{
    public string Id { get; set; }
    public string Status { get; set; }
    public string InjectedAt { get; set; }
    public int ProcessedSegments { get; set; }
    public string StreamVersion { get; set; }
}

public class TranscriptInjectionAudit
{
    public string StreamId { get; set; }
    public string InjectId { get; set; }
    public double LatencyMs { get; set; }
    public int SegmentsProcessed { get; set; }
    public string WebhookStatus { get; set; }
    public string Timestamp { get; set; } = DateTime.UtcNow.ToString("o");
}

You instantiate TranscriptMetadataInjector, call InitializeAsync(), and invoke InjectAsync() with your transcription output. The class handles authentication, validation, injection, retry logic, webhook synchronization, and audit logging automatically.

Common Errors & Debugging

Error: 401 Unauthorized

• Cause: OAuth token expired, missing mediastream:write scope, or invalid client credentials.
• Fix: Verify your OAuth configuration matches the Genesys Cloud application settings. Call _client.OAuth.GetTokenAsync() before injection. The SDK refreshes tokens automatically, but initial initialization requires a valid grant.
• Code Fix: Ensure Scopes includes mediastream:write. Add explicit token refresh in long-running services.

Error: 403 Forbidden

• Cause: OAuth application lacks permission to write to Media Streams, or the user token does not have the required role.
• Fix: Grant the mediastream:write permission to your OAuth application in the Genesys Cloud admin console. Verify that the service account has the Media Stream Administrator or equivalent role.
• Code Fix: No code change required. Update OAuth application permissions in Genesys Cloud.

Error: 429 Too Many Requests

• Cause: Exceeded Genesys Cloud rate limits for the Media Streams API or OAuth token endpoint.
• Fix: Implement exponential backoff with jitter. The example code reads the Retry-After header and delays the next request accordingly.
• Code Fix: The InjectTranscriptMetadataAsync method already handles 429 responses by reading Retry-After and retrying once. Add a retry counter for production workloads.

Error: 400 Bad Request

• Cause: Payload exceeds 10 KB limit, invalid UTF-8 encoding, empty segment array, or timestamp drift exceeds 300 seconds.
• Fix: Run the ValidateInjectPayload method before transmission. Trim segment text, reduce speaker matrix size, or adjust timestamp alignment directives.
• Code Fix: The validation pipeline throws descriptive ArgumentException messages. Log the exception details and adjust payload construction logic.

Error: 5xx Server Error

• Cause: Genesys Cloud streaming engine is undergoing maintenance or experiencing transient failures.
• Fix: Implement circuit breaker logic. Retry after a randomized delay between 5 and 30 seconds. Do not retry immediately as it increases load on the failing service.
• Code Fix: Wrap the injection call in a retry policy library like Polly. Fallback to local queue storage if the service remains unavailable.

Official References

• Genesys Cloud Media Streams API Documentation
• Genesys Cloud OAuth 2.0 Guide
• Genesys Cloud C# SDK Repository
• Media Streams Injection Endpoint Reference