.logscope

A Windows log analysis tool for SDETs and other technical users. Inspect, parse, filter, search, and monitor plain-text log files.

Current version: v0.4.8

Download

Grab the latest LogScope.exe from the Releases page. Single self-contained executable — no installer, no .NET runtime required, no admin rights.

What it does

Opening files

• Open a file or a folder — a single .log, or a whole directory scanned recursively for .log files.
• Format auto-detection — when opening an unknown file, .logscope detects the likely format and prompts you to Accept, Revise in the wizard, or fall back to Raw. You always keep raw access.
• Configurable extensions — add .txt, .csv, or any custom extension from Settings ▸ File Extensions.
• Workspace auto-refresh — the file tree updates automatically when files are added or removed from the workspace.

Viewing

• Table & raw views — parsed fields as columns, or the original text exactly as stored. Physical line numbers are always preserved.
• Show/hide columns — toggle any parsed column; the layout persists per profile.
• Multiline events — stack traces and continuation lines fold into the event above them; select a row to expand its detail.

Parsing profiles

• Delimiter & regex — tab-delimited, comma, |, ||, or any custom separator; or named-group regex.
• Field semantic types — assign Timestamp, Level, Module, Message, Thread, Device ID, Test Case, Run ID, or Result to any field. Level sorts by severity order (with custom levels), not alphabetically.
• Parser wizard — guided setup with a live preview of the first 50 lines; validates before saving.
• Profile assignment — assign a profile to a directory (applies recursively) or override per file.
• Import / export — share profiles as local JSON files.
• Multiline rule — define a "new event" regex so continuation lines (stack traces, wrapped messages) attach to the preceding event rather than becoming new rows.

Filtering & search

• Filter — by text or regex, any field, time range (when a Timestamp field is mapped), or flagged events only. Include and exclude conditions can be combined. Scope to a specific column with the field-scope picker.
• Filter presets — save the current filter as a named preset, optionally scoped to the active profile so it only appears when that profile is in use.
• Search — case-sensitive, whole-word, regex, column-specific, with next/prev navigation. "Search all rows" mode finds matches even when they are hidden by the current filter, and reports them without clearing your filter.
• Regex error feedback — invalid filter or search patterns show a red border and inline error message instead of crashing.

Visual rules

• Color rules — built-in rules tint ERROR/FATAL rows red and WARN rows amber. Author your own rules by field value, message substring, regex, or timestamp range — with configurable priority. Rules can color entire rows or individual fields.
• Flag rules — ERROR, WARN, FATAL, FAIL, ASSERT, TIMEOUT, EXCEPTION are flagged out of the box. Customize or add your own field-value or regex rules.
• Flagged indicators — badge counts appear in the file tree, tab headers, and the status bar. Each location is independently toggleable from Settings.

Streaming

• Live tail — enable streaming on any tab to follow a log that is actively being written. New lines are parsed, filtered, and color-ruled incrementally within ~1 second.
• Partial-write safety — lines are only emitted once a newline arrives; a write split across multiple flushes is held in a buffer and assembled correctly.
• CRLF support — \r\n line endings split across separate writes are handled correctly.
• File rotation / truncation — when a file is truncated or replaced, .logscope detects it, reloads from the beginning, and shows a reset notice.
• Multiline streaming — continuation lines (stack traces, etc.) fold into the preceding event row even when delivered in separate streaming batches.
• Auto-follow — the view scrolls to the tail automatically. Scroll up manually to pause following; a New entries: N badge appears. Click it to jump back to live.

Side-by-side comparison

• Split view — right-click any tab ▸ Split with active tab; or View ▸ Split all open logs.
• Draggable splitter — drag the divider between panes to resize them.
• Scroll-linked sync — scrolling one pane syncs the other automatically when synchronization is enabled.
• Sync modes — line-number (default) or nearest-timestamp. Sync is toggleable per pane. Falls back to line sync with a notice when a log has no parsed timestamp.

Large files

• Background loading — files are parsed on a background thread; a progress bar and Cancel button appear while loading.
• Chunked paging — files over 500,000 lines show a Load next 100k rows button in the status bar to page in more content on demand, backed by a byte-offset line index.

Other

• Sort & restore — click any column header to sort; the toolbar always offers Restore original file order.
• External actions — Reveal in Explorer, Open in default editor, Copy rows / raw text / line references.
• Encoding — auto-detects UTF-8 / UTF-16 LE/BE and falls back to Windows-1252 with a warning; force an encoding from the toolbar at any time.
• Window position — window size, position, and split layout persist across sessions.

Safety guarantees

• Read-only. Source log files and their folders are never modified, renamed, deleted, or written to.
• Offline. No telemetry, no network requests, no local server or listening port of any kind.
• Out-of-workspace state. All profiles, settings, presets, and indexes are stored under %APPDATA%\logscope — never inside the selected workspace.

Project layout

src/
  LogScope.Core/        — parsing, filtering, search, color/flag rules, streaming, workspace (no UI)
  LogScope.App/         — WPF desktop UI (MVVM) on top of Core
tests/
  LogScope.Core.Tests/  — xUnit + FluentAssertions (179 tests)

Build from source

Requires the .NET 8 SDK on Windows.

dotnet build LogScope.sln -c Release
dotnet test  tests/LogScope.Core.Tests
dotnet run   --project src/LogScope.App

Produce a standalone exe:

dotnet publish src/LogScope.App -c Release -r win-x64 --self-contained true \
  -p:PublishSingleFile=true -p:IncludeNativeLibrariesForSelfExtract=true

Built with TDD

The Core engine was built test-first, one behavior at a time. Every parser, filter, search, rule engine, and streaming watcher has tests written before the implementation.