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VDR.aihttpmock
httpmock is a lightweight HTTP mocking library for Rust that lets you create mock HTTP servers in tests. It supports request matching with regex and JSON, record-playback, HTTPS, and can run standalone via Docker.
Key facts
Objective fields from the source. Values we can't verify are shown as “Unknown” rather than guessed.
| Field | Value |
|---|---|
| Repository | httpmock/httpmock |
| Owner | httpmock |
| Primary language | Rust |
| License | MIT — OSI-approved |
| Stars | 664 |
| Forks | 60 |
| Open issues | 37 |
| Latest release | v0.8.3 (2026-02-04) |
| Last updated | 2026-07-06 |
| Source | https://github.com/httpmock/httpmock |
What httpmock is
A fully asynchronous Rust HTTP mocking library built with a fluent API for configuring mock responses and verifying requests. Provides synchronous and asynchronous APIs, custom matchers, fault simulation, and diff-based assertion reporting.
Get the httpmock source
Clone the repository and explore it locally.
git clone https://github.com/httpmock/httpmock.gitcd httpmock# follow the project's README for install & configurationNeed it deployed, integrated, or customized instead? DEV.co ships production installs.
Best use cases
Implementation considerations
- Add httpmock to dev-dependencies in Cargo.toml; minimal setup required to start a mock server in tests.
- Learn the fluent API for when/then mock configuration; expressive syntax scales well from simple stubs to complex matchers.
- Configure parallel test execution carefully if tests use shared mock server state; httpmock supports parallelism but test isolation is your responsibility.
- Use the detailed assertion error messages and diff output to debug mock mismatches; avoid brittle exact-match expectations where possible.
- For record-playback workflows, plan storage and versioning of recorded HTTP exchanges; no built-in dependency management.
When to avoid it — and what to weigh
- Non-Rust Projects — httpmock is Rust-specific. Non-Rust teams should evaluate language-appropriate alternatives like Mockoon, MSW, or Prism.
- Production Traffic Mocking at Scale — Designed for test environments. Lacks features (clustering, persistence, advanced routing) needed for large-scale production traffic capture or replay.
- Complex Protocol Mocking — Focused on HTTP/HTTPS. Projects requiring gRPC, WebSocket, or proprietary protocol mocking need specialized tools.
- Stateful Workflow Simulation — Best for request-response matching. Scenarios requiring complex multi-request state machines or session management may require custom logic or dedicated workflow engines.
License & commercial use
MIT License. Permissive OSI-approved license allowing use, modification, and distribution with minimal restrictions. Includes no liability warranty.
MIT License permits commercial use in closed-source or open-source projects without modification. No per-seat or per-deployment fees. Requires review of your internal IP policies if integrating substantial custom logic.
DEV.co evaluation signals
Editorial assessment — not user reviews. Directional, with an explicit confidence level.
| Signal | Assessment |
|---|---|
| Maintenance | Active |
| Documentation | Strong |
| License clarity | Clear |
| Deployment complexity | Low |
| DEV.co fit | Good |
| Assessment confidence | High |
HTTPS support included for secure mock communication. No hardened security audits mentioned. Use in test environments only; verify any custom matchers do not leak sensitive data. Mocking library inherits risks of underlying async runtime; keep Rust and dependencies patched.
Alternatives to consider
mockito
Simpler synchronous API; smaller feature set; good for basic HTTP mocking in Rust but lacks advanced matching and standalone mode.
Mockoon (polyglot)
Standalone desktop/CLI tool; supports any language; no code integration required; trade-off is less programmatic control and no in-process testing.
Wiremock (JVM/Node.js)
Cross-language HTTP mocking; Docker-first design; strong enterprise adoption; Rust binding available but not as mature as httpmock.
Build on httpmock with DEV.co software developers
Evaluate httpmock for your test suite. Start with a small integration test, review the fluent API and assertion clarity, then assess fit for your team's testing strategy.
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httpmock FAQ
Can I use httpmock in production?
Does httpmock support WebSockets or gRPC?
Can multiple tests run in parallel against the same mock server?
Is there a commercial support or SLA?
Custom software development, end to end
Standing up httpmock properly takes more than a deploy. As a software development agency, DEV.co handles the open-source testing architecture, the web development on top, and the operational work underneath.
Ready to streamline your Rust testing?
Evaluate httpmock for your test suite. Start with a small integration test, review the fluent API and assertion clarity, then assess fit for your team's testing strategy.