Class WebRtcDataChannelSession

One-shot WebRTC peer for a single SQL operation against an Agent.

Lifecycle (per the per-SQL token decision):

1. POST /api/data-session/start (Bearer + agentApiKey) → sessionId + JWT + iceServers.
2. Open WS /api/data-session/{sessionId}/signal?token=jwt.
3. Build RTCPeerConnection, create a DataChannel, generate offer, wait for ICE gather complete, forward offer over the signaling WS. The Hub routes it to the Agent and the answer comes back wrapped in {"source":"hub","body":"<agent reply json>"}.
4. setRemoteDescription(answer), wait DC open (≤10s).
5. Send {requestId, action, data} on the DC, collect executing / fetching / data / done messages, return the deserialized payload.
6. Close the DC + peer + signaling WS; the session dies with the SQL.

If anything fails before DataChannelReadyAsync returns true, the caller falls back to the existing HTTP path.

Inheritance

object

WebRtcDataChannelSession

Implements

IAsyncDisposable

Inherited Members

object.GetType()

object.ToString()

object.Equals(object)

object.Equals(object, object)

object.ReferenceEquals(object, object)

object.GetHashCode()

Namespace: Reportman.Hub.Client.DataChannel

Assembly: Reportman.DataChannel.dll

Syntax

public sealed class WebRtcDataChannelSession : IAsyncDisposable

Properties

IsAlive

True when the negotiated DataChannel is open and the session hasn't been disposed. The pool reads this to decide whether to reuse the cached session or evict it and open a fresh one.

Declaration

public bool IsAlive { get; }

Property Value

Type	Description
bool

IsBusy

True while at least one ExecuteAsync(string, object, CancellationToken) is in flight. The pool reads this in its idle/max-life check to avoid evicting a session whose query is still running — without this guard a query lasting longer than the pool's idle window (60s) or max-lifetime (10min) would be killed mid-flight as the timer fires against a session whose Touch() only ran at the start of the request.

Declaration

public bool IsBusy { get; }

Property Value

Type	Description
bool

Mode

Declaration

public ConnectionMode Mode { get; }

Property Value

Type	Description
ConnectionMode

Methods

DisposeAsync()

Declaration

public ValueTask DisposeAsync()

Returns

Type	Description
ValueTask

ExecuteAsync(string, object, CancellationToken)

Sends a single {requestId, action, data} request on the live DataChannel and returns the fully reassembled payload bytes. The caller decodes them per action: SQL-shaped actions get FastSerializer-binary bytes; metadata actions get UTF-8 JSON bytes. Progress messages from the Agent are surfaced via the constructor's onProgress callback. A 15s gap without any message from the Agent throws — the request is considered dead.

Declaration

public Task<byte[]> ExecuteAsync(string action, object data, CancellationToken ct)

Parameters

Type	Name	Description
string	action
object	data
CancellationToken	ct

Returns

Type	Description
Task<byte[]>

SendKeepaliveAsync(CancellationToken)

Sends a tiny ping over the DataChannel and waits briefly for the pong. Used by the pool to keep the NAT mapping warm during idle windows so the next real query doesn't pay the full STUN/ICE/DTLS setup cost. Returns true if the channel was alive at send time (pong arrival is not strictly required — the outbound UDP packet alone refreshes the router's binding).

Declaration

public Task<bool> SendKeepaliveAsync(CancellationToken ct = default)

Parameters

Type	Name	Description
CancellationToken	ct

Returns

Type	Description
Task<bool>

TryOpenAsync(HttpClient, Uri, string?, object, Action<QueryProgress>?, CancellationToken)

Attempts to negotiate a fresh DataChannel. startBody is the JSON body for POST /api/data-session/start; accepts either new { agentApiKey } or new { hubDatabaseId }. Returns null on any failure; the caller should then fall back to the HTTP path.

Declaration

public static Task<WebRtcDataChannelSession?> TryOpenAsync(HttpClient http, Uri apiBaseUri, string? bearer, object startBody, Action<QueryProgress>? onProgress, CancellationToken ct)

Parameters

Type	Name	Description
HttpClient	http
Uri	apiBaseUri
string	bearer
object	startBody
Action<QueryProgress>	onProgress
CancellationToken	ct

Returns

Type	Description
Task<WebRtcDataChannelSession>

Events

DiagnosticLog

Raised for every direct-channel negotiation trace line. A UI host (e.g. the Designer's "Net Log" tab) can subscribe to surface the handshake live: iceServers, candidates exchanged, answer arrival, peer state and where it threw. Fired on whatever thread produced the line (often a SIPSorcery worker) — subscribers must marshal to their UI thread. Static because sessions are created deep inside the engine (DirectAgentExecutor) with no handle to the UI.

Declaration

public static event Action<string>? DiagnosticLog

Event Type

Type	Description
Action<string>

Implements

IAsyncDisposable