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API Testing · /// OpenAPI Load Testing

Drop in an OpenAPI spec. Get a load test.

The visual flow editor imports OpenAPI / Swagger specs and scaffolds operations automatically. Author the user journey across imported endpoints visually, then replay as a load test AND as a continuous synthetic check — no script project, no hand-authored test library.

OpenAPI / Swagger import28 node typesLoad + monitoring on one engine

API sources — OpenAPI spec imported, endpoints scaffolded.

The Problem

OpenAPI specs are documentation. Not tests.

Most teams ship OpenAPI / Swagger specs as living documentation — and then maintain a separate test library by hand. The spec drifts; the test library drifts; the gap shows up in production.

Hand-authored tests drift from spec.

A new endpoint added to the spec doesn’t automatically get a test. Test coverage decays with every release until someone audits it manually.

Two systems, two source-of-truth.

OpenAPI spec in one repo, Postman collection or VuGen scripts in another. The spec changes; nothing else updates automatically.

Load testing the spec is awkward.

Generic load tools don’t consume OpenAPI directly — they need scripts hand-authored from the spec, which adds yet another translation step.

Why OpenAPI-driven load testing

Spec → scaffold → flow → load + monitoring.

Import the OpenAPI spec. The flow editor scaffolds operations automatically — each endpoint becomes a node template. Author the user journey across imported endpoints; replay across modes. The spec stays the source of truth.

OpenAPI import

Drop in the OpenAPI / Swagger spec; operations scaffolded automatically. Endpoint changes re-import — test coverage tracks spec evolution.

Visual journey authoring

Drag-drop the imported endpoints into a user journey. 28 node types — branching, loops, assertions, custom code — compose end-to-end flows.

Load + monitoring replay

The flow authored once replays as a load test (50–25k vUsers) AND as a continuous synthetic check. One asset, two operational modes.

Spec → scaffold

OpenAPI imported, endpoints scaffolded.

Drop the OpenAPI / Swagger file into the API Sources view. Each operation becomes a node template ready to drop into a flow. Spec changes re-import; test coverage tracks the spec.

  • OpenAPI 3.x and Swagger 2.x both supported.
  • Endpoint metadata, parameter schemas, response shapes imported automatically.
  • Re-import detects new endpoints — coverage tracks spec evolution.
  • Combines with custom code nodes for cases the spec doesn’t cover.

API sources — OpenAPI spec imported, endpoints scaffolded.

Author the journey

Drag, drop, connect, replay.

Compose the user journey visually across imported endpoints. 28 node types handle branching, loops, assertions, custom code. The same flow runs as load + monitoring without re-authoring.

  • 28 node types: HTTP, REST, SQL, branching, loops, assertions, custom code, OpenAPI import.
  • Drag-drop authoring — connect endpoint nodes into multi-step journeys.
  • Per-step assertions on payload, status, latency.
  • Replayable as load test AND as continuous synthetic check.

Flow canvas — multi-node API journey visual.

Outcomes

What OpenAPI-driven load testing looks like.

Test scaffolding

Before

Hand-authored

After

OpenAPI imported

auto
Spec ↔ test sync

Before

Manual

After

Re-import detects

tracked
Load + monitoring reuse

Before

Two libraries

After

One flow

unified
Coverage decay

Before

Per release

After

Tracked to spec

↓ drift

Import your OpenAPI spec on a call.

Bring the spec; we’ll import it in the visual editor, scaffold the operations, author a multi-step user journey, and run it as a load test — live.

Questions

Frequently asked.

Does the import support OpenAPI 3.x and Swagger 2.x?

Yes — both versions are supported. Endpoint metadata, parameter schemas, and response shapes are imported automatically. Re-import detects added or modified endpoints.

Can the imported flow run as both load and monitoring?

Yes. The flow authored from the imported spec replays as a load test (50–25k vUsers) AND as a continuous synthetic monitoring check (every minute). One asset, two modes.

What happens when the OpenAPI spec changes?

Re-import the spec; the flow editor detects added or modified endpoints. Existing flows continue to work; new endpoints become available as draggable nodes for additional journeys.

Can I add custom logic that isn’t in the spec?

Yes. The 28 node types include custom-code nodes for cases the spec doesn’t cover — pre-request setup, post-response processing, complex assertions.

How does CI/CD integration work?

Test runs trigger from pipeline stages via the LoadGen API. Results gate the deploy on assertion failure, latency regression, or error-rate threshold breach. Analytics + AI flags regressions per release.

What does OpenAPI load testing cost?

API Testing is part of the LoadGen platform. Load Testing tier is €1,099 per week at 50 vUsers; Monitoring is €899 per Agent per month. Multi-module bundles are quoted on a call.

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