12 KiB
Endpoint agent contract (C# build reference)
Companion to DESIGN-DECISIONS-agent.md. This is the concrete wire contract the
future C# agent targets, derived from EndpointsPlugin.get_collector_schema()
and the generic collector dispatcher in shopdb/core/api/collector.py. When the
schema changes, update this file in the same change.
1. Transport
- Method/URL:
POST {baseurl}/api/collector/endpoints - Auth header:
X-API-Key: <collector key>(Bearer token also accepted). The key is a UI-managed, endpoints-only service token minted from Settings -> Endpoint agent key (section 6). A bootstrap.envcollector key still works until the first UI key is generated, then it is switched off (section 6). No querystring fallback. - Body:
application/json, a single flat object (NOT an array). One POST per report per endpoint. - Identity field:
hostname(required, case-insensitive).
2. Request payload
Only hostname is required. Every other field is optional; the server upserts
only the keys that are present, so a lightweight report can omit inventory
arrays. adopt is first-contact only.
{
"hostname": "SHOP-PC-014", // required, resolved to computers.hostname
"adopt": true, // first run ONLY; delegates PC creation to computers plugin
"loggedinuser": "j.smith",
"serialnumber": "5CD1234ABC", // adoption subset (forwarded to computers)
"pctype": "CNC Controller", // adoption subset
"machinenumber": "12345", // adoption subset; "" or "9999" == none
"agentversion": "1.0.0",
"trayversion": "1.0.0", // file version of the interactive tray exe, omitted if no tray
"lastboottime": "2025-01-14T06:12:00Z", // ISO-8601 UTC
"uptimeseconds": 86400,
"idleseconds": 120,
"cpupercent": 12.5,
"memorypercent": 47.0,
"services": [ /* opaque array, stored as JSON */ ],
"ports": [ /* opaque array */ ],
"interfaces": [
{
"alias": "Intel(R) Ethernet Connection", // adapter description
"ipv4": "10.20.30.40", // "" if none
"mac": "AA:BB:CC:DD:EE:FF",
"gateway": "10.20.30.1", // "" for the static machine-IPS NIC
"subnet": "255.255.255.0",
"dhcp": false
}
],
"scheduledtasks": [ /* opaque array */ ],
"events": [
{
"eventid": 6008, // required per item; non-catalog IDs are dropped, not errored
"eventchannel": "System",
"eventsource": "EventLog",
"eventtime": "2025-01-14T06:11:58Z",
"eventmessage": "The previous system shutdown was unexpected.",
"fields": { "any": "extra" } // opaque object, stored as JSON
}
]
}
Notes:
adopt=trueis sent ONLY by the installer's first run. Steady-state reports omit it (or sendfalse). After adoption, an unknown hostname is a hard validation error again (DESIGN-DECISIONS-agent.md 1a).- The adoption subset (
serialnumber,pctype,machinenumber, plusloggedinuser) is forwarded to thecomputerscollector so the newly created PC is not a bare shell. Send them on first contact. services/ports/interfaces/scheduledtasksare stored verbatim as JSON; the server does not validate their inner shape yet. Keep them stable so the UI can render them later.interfacesreports EVERY hardware NIC (not just the primary) so the gatewayless static NIC that links a PC to its machine's IPS is preserved (DESIGN-DECISIONS-agent.md 9.3); each entry is{alias, ipv4, mac, gateway, subnet, dhcp}.machinenumberis discovered on-box by the agent from the eDNC registry (HKLM\SOFTWARE\[WOW6432Node\]GE Aircraft Engines\DNC\General:MachineNo) or the UDCudc_settings_*.json(GeneralSettings.MachineNumber), in that order (DESIGN-DECISIONS-agent.md 9.4/9.5).""or"9999"means none.
3. Response
Success (HTTP 200), ADR-006 envelope:
{
"status": "ok",
"action": "created", // "created" first time, "updated" thereafter
"assetid": 4821,
"identityvalue": "SHOP-PC-014",
"warnings": [
"adopted new computer for hostname: 'SHOP-PC-014'" // present only on adoption
]
}
Validation failure (HTTP 400) - e.g. unknown hostname with adopt absent:
{ "status": "error", "error": { "code": "VALIDATION_ERROR",
"message": "could not resolve hostname to a computer: 'SHOP-PC-014'" } }
Agent handling: treat non-200 as retryable except a VALIDATION_ERROR that
names an unresolved hostname on a NON-first-contact report - that means the PC
was removed server-side; surface it, do not spin.
4. C# DTOs
Match the JSON keys EXACTLY (lowercase, no underscores) to satisfy the naming rule; use attributes so C# properties can stay PascalCase without a camelCase serializer changing the wire keys.
using System.Text.Json.Serialization;
public sealed class EndpointReport
{
[JsonPropertyName("hostname")] public string Hostname { get; set; } = "";
[JsonPropertyName("adopt")] public bool? Adopt { get; set; }
[JsonPropertyName("loggedinuser")] public string? LoggedInUser { get; set; }
[JsonPropertyName("serialnumber")] public string? SerialNumber { get; set; }
[JsonPropertyName("pctype")] public string? PcType { get; set; }
[JsonPropertyName("machinenumber")] public string? MachineNumber { get; set; }
[JsonPropertyName("agentversion")] public string? AgentVersion { get; set; }
[JsonPropertyName("trayversion")] public string? TrayVersion { get; set; }
[JsonPropertyName("lastboottime")] public DateTimeOffset? LastBootTime { get; set; }
[JsonPropertyName("uptimeseconds")] public long? UptimeSeconds { get; set; }
[JsonPropertyName("idleseconds")] public long? IdleSeconds { get; set; }
[JsonPropertyName("cpupercent")] public double? CpuPercent { get; set; }
[JsonPropertyName("memorypercent")] public double? MemoryPercent { get; set; }
[JsonPropertyName("services")] public object[]? Services { get; set; }
[JsonPropertyName("ports")] public object[]? Ports { get; set; }
[JsonPropertyName("interfaces")] public object[]? Interfaces { get; set; }
[JsonPropertyName("scheduledtasks")]public object[]? ScheduledTasks { get; set; }
[JsonPropertyName("events")] public EndpointEventRecord[]? Events { get; set; }
}
public sealed class EndpointEventRecord
{
[JsonPropertyName("eventid")] public int EventId { get; set; }
[JsonPropertyName("eventchannel")] public string? EventChannel { get; set; }
[JsonPropertyName("eventsource")] public string? EventSource { get; set; }
[JsonPropertyName("eventtime")] public DateTimeOffset? EventTime { get; set; }
[JsonPropertyName("eventmessage")] public string? EventMessage { get; set; }
[JsonPropertyName("fields")] public Dictionary<string, object>? Fields { get; set; }
}
public sealed class CollectorResponse
{
[JsonPropertyName("status")] public string Status { get; set; } = "";
[JsonPropertyName("action")] public string? Action { get; set; }
[JsonPropertyName("assetid")] public int? AssetId { get; set; }
[JsonPropertyName("identityvalue")] public string? IdentityValue { get; set; }
[JsonPropertyName("warnings")] public string[]? Warnings { get; set; }
}
Serializer settings: DefaultIgnoreCondition = JsonIgnoreCondition.WhenWritingNull
so omitted fields are not sent (server upserts only present keys). Send UTC ISO-8601.
5. "Build site agent" settings flow (build cadence)
Goal: an operator in ShopDB Settings produces an instance-locked .exe that
knows its server URL and its collector key, needing no manual config on the
client.
- Settings -> "Build site agent": operator picks/creates a collector-scoped
managed token (the same token accepted by
X-API-Keyon/api/collector/endpoints). This binds the build to one ShopDB instance. - Server stamps a small config (base URL + token + reporting cadence) into the agent build artifact. Instance-locked = the token only works against that server, and the server can revoke it to kill a leaked build.
- First run on a client:
- Collect the ShopDB PowerShell asset-collector data set (minus the CSV emit): hostname, logged-in user, serial number, pc type, machine number, boot time, plus the curated event tail.
- POST once with
adopt=true. The endpoints plugin delegates PC creation to thecomputerscollector, then writes the firstEndpointStatein the same commit. The endpoint appears in the Fleet UI immediately - no second call, no separate enrollment endpoint.
- Subsequent runs POST on the configured cadence with
adoptomitted; strict hostname resolution applies from then on.
Open item (from DESIGN-DECISIONS-agent.md 1a): whether adopt stays a
per-report flag or is promoted to a site setting (strict vs self-adopting
fleet). Default proposed: agent sends adopt=true on first run only.
6. UI-managed agent key (kill switch)
The endpoint agent authenticates with a single UI-managed key scoped to ONLY
collector.ingest.endpoints, so rotating or revoking it stops all
endpoint-agent traffic without affecting the computers or geenforce collectors.
- Settings -> Endpoint agent key (admin only) generates the key. The full secret
is shown ONCE at generation and stored only as a hash afterwards; configure it
as the agent
X-API-Key. - Generating a key is a hard cutover: any previous endpoint key is revoked in the
same request, and the bootstrap
.envfallback for endpoints is switched off (plugin.endpoints.envkeyfallback-> false), so the managed key becomes the sole credential. - Regenerate to rotate (old key dies immediately). Revoke to stop all endpoint-agent reporting until a new key is generated - the kill switch for a leaked agent.
- Backend:
GET/POST /api/endpoints/agentkey,POST /api/endpoints/agentkey/regenerate,DELETE /api/endpoints/agentkey. These use themint_service_token/list_service_tokens/revoke_service_tokenscontract helpers (shopdb.api, contract 0.22.0).
The bootstrap .env key (COLLECTOR_API_KEY[_ENDPOINTS]) remains only as a
first-run path before a UI key exists; it cannot be the runtime kill switch
because container env is injected at boot and cannot be rotated live.
7. Command channel (WebUI -> agent)
The WebUI can send an endpoint an ALLOWLISTED command (never an arbitrary
command string). Delivery is agent-initiated long-poll, so shop-floor PCs open
no inbound port: the agent makes an outbound request the server holds open until
a command is queued, runs it locally, and posts the result back. All three
routes reuse the same endpoints collector key (section 6) via X-API-Key, so
the command channel shares the kill switch and adds no second secret.
Allowlisted actions (server source of truth: plugins/endpoints/commands.py):
mtconnect_start- run the MTConnect UDC agent start script (C:\ProgramData\UDC\MTConnect_UDC\Agent\run.bat).mtconnect_stop- stop the running MTConnect UDC agent process.mtconnect_status- report whether the MTConnect UDC agent is running.
7.1 Claim the next command (long-poll)
GET {baseurl}/api/endpoints/commands/next?hostname=<hostname>
- Auth:
X-API-Key(endpoints collector key). - The server holds the request open up to ~25s. If a command is queued it is atomically claimed (marked running) and returned; only one poll ever claims a given command.
- Command queued (HTTP 200):
{ "status": "ok", "data": { "endpointcommandid": 91, "action": "mtconnect_start" } }
- Nothing queued within the hold window: HTTP 204 (no body). Re-poll.
7.2 Report a command result
POST {baseurl}/api/endpoints/commands/<endpointcommandid>/result
- Auth:
X-API-Key(endpoints collector key). - Body:
{
"succeeded": true, // required; false marks the command failed
"message": "MTConnect started", // short summary, optional (<= 2000 chars)
"mtconnectrunning": true, // optional; observed run state after the action
"detail": { "any": "extra" } // optional structured detail, stored as JSON
}
- When
mtconnectrunningis present the server caches it on the endpoint'sEndpointState(mtconnectrunning+mtconnectcheckedat) so the WebUI toggle shows a real state between polls. Everymtconnect_*action SHOULD probe and report the resulting run state so the toggle never lies.
7.3 Enqueue (WebUI side, for reference)
POST /api/endpoints/<assetid>/commands with { "action": "mtconnect_start" },
gated by user JWT + endpoints.command. Only one command may be in flight per
endpoint (a second enqueue returns HTTP 409 until the first finalizes).