---
title: mdlLogging
summary: API reference for mdlLogging.
status: draft
owner: <owner>
last_reviewed: 2026-07-23
library: SAIF.Framework.SecurityModule
reference_type: package
---

# mdlLogging

`mdlLogging` is a shared VB `Module` that centralizes `log4net`-backed logging for the library. It exposes a lazily-initialized `Log` instance and convenience methods that format each message with request/host context before writing it, and is consumed by every authenticator class in the library (for example, `clsSecurityModule.AuthRequest_Handler`).

## Purpose
- Provide a single, shared `log4net` logger instance for the library, keyed by the `clsSecurityModule` type name.
- Standardize log message formatting to include the requesting host address, request URL, application name, and call-stack context alongside the caller-supplied message.

## Context
- Namespace: `SAIF.Framework.SecurityModule`
- Assembly/package: `SAIF.Framework.SecurityModule` (packaged inside the `SAIF.BOF.Framework` NuGet package)

## Public members
| Member | Signature | Purpose |
| --- | --- | --- |
| `Log` | `Public ReadOnly Property Log As ILog` | Lazily creates (on first access) and returns a `log4net.ILog` instance obtained via `LogManager.GetLogger(GetType(clsSecurityModule).Name)`; subsequent calls reuse the cached instance. |
| `LogInfo` | `Public Sub LogInfo(msg As String)` | Formats and writes `msg` at `log4net` Info level via `Log.InfoFormat`. |
| `LogWarn` | `Public Sub LogWarn(msg As String)` | Formats and writes `msg` at `log4net` Warn level via `Log.WarnFormat`. |
| `LogError` | `Public Sub LogError(msg As String)` | Formats and writes `msg` at `log4net` Error level via `Log.ErrorFormat`. |
| `LogDebug` | `Public Sub LogDebug(msg As String)` | Formats and writes `msg` at `log4net` Debug level via `Log.DebugFormat`. |

## Behavioral notes
- Every log call is routed through the private `LogMsg` helper, which builds a comma-separated parameter list: client host address, current request URL, application path (leading `/` stripped), a synthesized call-stack trail, and the caller's message.
- The call-stack trail (`GetStackFrames`) walks the current stack, keeping only frames declared on `clsSecurityModule`, reverses the order, and excludes frames whose method name starts with `ASSERT` or `GETSTACKFRAMES`, joining the remaining names with `->`.
- Because `GetHostAddress`/`GetRequestURL`/`LogMsg` read from `System.Web.HttpContext.Current.Request`, all public logging methods require an active ASP.NET request context; calling them outside a request pipeline would raise a null-reference exception.*

## Constraints and usage notes
- All public members are module-level (shared); `mdlLogging` is not intended to be instantiated.
- The underlying `log4net` logger name is always `clsSecurityModule`, regardless of which class in the library invokes `LogInfo`/`LogWarn`/`LogError`/`LogDebug`.

> **Note:** Statements marked with * were inferred from code structure, naming conventions, or
> contextual evidence where direct confirmation was not available in source artifacts. Statements
> marked with ** could not be confirmed; treat as unknown until verified. Statements marked with
> † were retrieved from dependency library documentation via the Legends CLI RAG service. They
> describe inherited behavior from the indicated origin library and should be verified if the
> dependency version changes.

## Sources
- `SAIF.Framework.SecurityModule\mdlLogging.vb`