# Serilog.Sinks.Seq

**Kind:** Service

**Source:** `Pams/API/Pams.API/Pams.API.csproj` (line 1)

**Part of:** [Pams](subsystem-pams)

NuGet package dependency

`Serilog.Sinks.Seq` is a NuGet dependency for the Pams API that sends Serilog log events to a Seq server. It connects application logging configuration to Seq ingestion endpoints for centralized event storage and querying.

## Diagram

```mermaid
sequenceDiagram
    participant API as Pams API
    participant Serilog as Serilog
    participant Sink as Serilog.Sinks.Seq
    participant Seq as Seq Server

    API->>Serilog: Write log event
    Serilog->>Sink: Format event for Seq
    Sink->>Seq: POST event batch
    Seq-->>Sink: Accept response
```

## Usage

```ts
const seqUrl = "https://seq.example.com/api/events/raw";
const apiKey = process.env.SEQ_API_KEY;

const logEvent = {
  "@t": new Date().toISOString(),
  "@l": "Information",
  "@mt": "Pams API request completed",
  RequestPath: "/api/patients",
  StatusCode: 200
};

await fetch(seqUrl, {
  method: "POST",
  headers: {
    "Content-Type": "application/vnd.serilog.clef",
    "X-Seq-ApiKey": apiKey ?? ""
  },
  body: `${JSON.stringify(logEvent)}\n`
});
```

## AI Coding Instructions

- Configure `Serilog.Sinks.Seq` in the Pams API logging pipeline rather than posting log events manually from application code.
- Keep the Seq server URL and API key in configuration or environment variables, not source code.
- Include structured properties such as request paths, status codes, user identifiers, and correlation identifiers in log events.
- Use Seq ingestion failures as logging diagnostics; do not allow logging transport failures to interrupt API request handling.

## Used by

1 reference from 1 file. Each is a place in this repository where the symbol is actually used — go read one rather than trusting an example.

### Injected or called by (1)

- `Pams.API` — `Pams/API/Pams.API/Pams.API.csproj`:1