WiretapKMP¶

Kotlin Multiplatform network inspection and mocking SDK. Intercepts HTTP, WebSocket, and SSE (Server-Sent Events) traffic from Ktor, OkHttp, and URLSession clients. Logs to local SQLite. Built-in Compose UI for inspection. Mock and throttle rules engine. No proxy server needed.

KMP Plugins¶

Client	Android	iOS	JVM Desktop
Ktor	✅	✅	✅
OkHttp	✅	—	✅

Swift Wrapper¶

Client	iOS
URLSession	✅

Inspection Support¶

Client	HTTP	WebSocket	SSE
Ktor	✅	✅	✅
OkHttp	✅	✅	✅
URLSession	✅	—	—

wiretap-urlsession is a dedicated Swift wrapper exported as an XCFramework via KMMBridge/SPM. It wraps NSURLSession with logging and rule support for native iOS projects.

Screenshots¶

HTTP Inspector¶

OverviewRequestResponse

HTTP Overview

HTTP Request

HTTP Response

WebSocket Inspector¶

ConnectionsMessages

WebSocket List

WebSocket Detail

Rules Engine¶

Notifications¶

HTTPWebSocket

HTTP Notification

WebSocket Notification

List-Detail Pane (Tablet / Desktop)¶

List-Detail Pane

HTTP Logging¶

Every request and response is captured automatically when the plugin is installed. Logged data includes:

URL, method, request/response headers, request/response bodies
Response status code and duration (nanosecond precision)
Protocol version and remote address
TLS details (OkHttp only): TLS version, cipher suite, certificate CN, issuer CN, certificate expiry

Requests appear in the inspector immediately as "in-progress" and update when the response arrives.

WebSocket Logging¶

Full WebSocket lifecycle tracking:

Connection open/close/failure with status transitions
Close codes and reasons
Every sent and received message (text and binary) with timestamps and byte counts
Ktor: wrap session with wiretapped() for automatic message interception
OkHttp: wrap listener with WiretapOkHttpWebSocketListener for automatic event capture

SSE (Server-Sent Events) Logging¶

Full SSE connection lifecycle tracking:

Connection open/close/failure with status transitions
Every incoming event with event type, data payload, event ID, retry interval, and byte count
Ktor: wrap SSE session with wiretapped() for automatic event interception
OkHttp: wrap listener with WiretapOkHttpEventSourceListener for automatic event capture

API Mocking¶

Return fake responses without hitting the network. Rules match on method, URL, headers, and body using exact, contains, or regex matching. All criteria use AND logic. Mock responses bypass the network entirely and appear in the inspector with a Mock badge.

Mocked RequestsMocked ResponseMock Rule Setup

Mocked Requests

Mocked Response

Mock Rule

Request Throttling¶

Add artificial delay before the request reaches the network. Supports fixed delay or random delay within a range. The real network call still happens — throttling only adds delay.

Throttle Rule SetupMock + Throttle

Throttle Rule

Mock + Throttle Rule

Header Masking¶

Control how headers are stored in the log database. Original request/response headers are never mutated.

HeaderAction.Keep — Log as-is (default)
HeaderAction.Mask("***") — Replace value with mask string
HeaderAction.Skip — Omit from logs entirely

Log Retention¶

LogRetention.Forever — Keep all logs indefinitely (default)
LogRetention.AppSession — Clear all logs on first request after app start
LogRetention.Days(n) — Auto-prune entries older than N days on each capture. Uses indexed timestamp queries.

Request Filtering¶

shouldLog controls which requests are stored in the database. Requests that don't pass the filter are still subject to mock/throttle rules — they just won't appear in the inspector.

shouldLog = { url, method -> url.contains("/api/") }

Built-in Inspector UI¶

Compose Multiplatform UI with:

HTTP log list with search and filtering
Request/response detail view (Overview, Request, Response tabs)
WebSocket connections list and message stream view
SSE connections list and event stream view
Rule management (create, edit, enable/disable, delete) with conflict detection
Two-pane layout on wide screens
Copy buttons for headers and bodies
Share as file — export any HTTP log as a text file via the platform share sheet (Android/iOS) or open directly (Desktop)

Shake to Launch¶

Wiretap includes a built-in shake detector that opens the inspector UI when the device is shaken. Call enableWiretapLauncher() once during app startup.

Platform	Trigger
Android	Shake gesture (accelerometer sensor)
iOS	Shake gesture (`UIWindow.motionEnded` via `wiretap-shake` module)
JVM Desktop	`Ctrl+Shift+D` keyboard shortcut

// Call once at app startup (e.g., Application.onCreate or main())
enableWiretapLauncher()

No additional setup is needed — the launcher registers itself and presents the Wiretap inspector automatically on trigger.

No-op Variants¶

Every plugin module has a matching no-op module with identical API surface and zero runtime overhead. Swap the dependency for release builds — no conditional code needed.

Debug	Release
`wiretap-ktor`	`wiretap-ktor-noop`
`wiretap-okhttp`	`wiretap-okhttp-noop`

For URLSession, use config.enabled = false with #if DEBUG instead of a separate no-op module.