FauxRPC

FauxRPC is a powerful tool that empowers you to accelerate development and testing by effortlessly generating fake implementations of gRPC, gRPC-Web, Connect, and REST services. If you have a protobuf-based workflow, this tool could help.

Why FauxRPC?

• Faster Development & Testing: Work independently without relying on fully functional backend services.
• Isolation & Control: Test frontend components in isolation with controlled fake data.
• Multi-Protocol Support: Supports multiple protocols (gRPC, gRPC-Web, Connect, and REST).
• Prototyping & Demos: Create prototypes and demos quickly without building the full backend. Fake it till you make it.
• API Stubs: Define static or dynamic API responses with powerful stubs featuring CEL expressions for precise behavior control. Stubs can be defined using config files or dynamically at runtime.
• Improved Collaboration: Bridge the gap between frontend and backend teams.
• Plays well with others: Test data from FauxRPC will try to automatically follow any protovalidate constraints that are defined.
• Request Validation: Ensure data integrity with automatic request validation using protovalidate. Catch errors early and prevent invalid data from reaching your application logic.

See the the documentation website for more!

Get Started

Install via source

go install github.com/sudorandom/fauxrpc/cmd/[email protected]

Pre-built binaries

Binaries are built for several platforms for each release. See the latest ones on the releases page.

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Usage

Running the Server

The core command is fauxrpc run, which starts the server based on your Protobuf schema. You can combine flags to configure the server on startup.

For example, this command starts the server with a specific schema, loads a stub for a method, and enables the dashboard:

fauxrpc run --schema=eliza.binpb --stubs=example/stubs.eliza/say.json --dashboard

Loading Schemas

You must provide Protobuf descriptors so FauxRPC knows which services to fake. Schemas can be loaded from multiple sources, and you can mix and match them.

From a local file:

fauxrpc run --schema=service.binpb

From the Buf Schema Registry (BSR)

fauxrpc run --schema=buf.build/bufbuild/eliza

From multiple sources at once

fauxrpc run --schema=service.binpb --schema=buf.build/bufbuild/eliza

Using Stubs

While FauxRPC generates random fake data by default, stubs let you define specific, predictable responses for your RPCs. This is great for testing specific scenarios.

You can load a single stub file or an entire directory of them.

Load a single stub file

fauxrpc run --schema=eliza.binpb --stubs=example/stubs.eliza/say.json

Load all stubs from a directory

fauxrpc run --schema=eliza.binpb --stubs=example/stubs.eliza/

Making Requests with fauxrpc curl

FauxRPC includes a handy built-in client, fauxrpc curl, for making requests to your services without needing external tools. It automatically sources the schema to provide a seamless testing experience.

Hit all RPCs in a service with default data

fauxrpc curl --http2-prior-knowledge --schema=buf.build/bufbuild/registry

Hit a specific RPC

fauxrpc curl --http2-prior-knowledge --schema=buf.build/bufbuild/registry buf.registry.plugin.v1beta1.LabelService/ListLabels

Using server reflection

If no --schema option is provided, server reflection will be used to figure out the type and service information.

fauxrpc curl --http2-prior-knowledge buf.registry.plugin.v1beta1.LabelService/ListLabels

Dashboard

Enhance your FauxRPC experience with the interactive dashboard, providing real-time insights into your server's operations.

To enable the dashboard, simply start FauxRPC with the --dashboard option:

fauxrpc run --schema=service.binpb --dashboard

Access the dashboard in your browser at http://127.0.0.1:6660/fauxrpc.

The dashboard provides:

• 📊 Summary: View overall server statistics.
• 📜 Request Log: Live stream of all incoming requests.
• 📁 Schema Browser: Explore all Protobuf schemas loaded into the server.
• 🔌 Stubs: Manage and view details of registered stubs.
• 📚 API Documentation: Access auto-generated API documentation.

Go to the documentation website for more!