gRPC component

This component runs a gRPC server with sane defaults and built‑in observability (OpenTelemetry tracing/metrics) and health.

• Package: github.com/beatlabs/patron/component/grpc
• Component type: implements Run(ctx context.Context) error
• Defaults: registers gRPC health server, adds OTel stats handler, optional server reflection

Quick start

import (
    patrongrpc "github.com/beatlabs/patron/component/grpc"
)

// Create component and register your service implementations.
cmp, err := patrongrpc.New(50051)
if err != nil { /* handle */ }

// Register generated gRPC servers on cmp.Server().
// examples.RegisterGreeterServer is generated from greeter.proto.
examples.RegisterGreeterServer(cmp.Server(), greeterImpl)

// Add the component to your Patron service and run.
svc, _ := patron.New("example-service", patron.WithComponents(cmp))
_ = svc.Run(ctx)

See a full runnable example in examples/service/grpc.go.

Options

// WithServerOptions: provide raw grpc.ServerOption values
cmp, err := patrongrpc.New(50051,
    patrongrpc.WithServerOptions(
        // e.g., add interceptors, keepalive, limits, creds, etc.
        grpc.UnaryInterceptor(myUnaryInterceptor),
    ),
)

// WithReflection: opt‑in to server reflection (useful in local/dev tools)
cmp, err := patrongrpc.New(50051, patrongrpc.WithReflection())

Notes

• Server options you pass replace any previously set options on the component. Patron always appends an OTel StatsHandler internally for tracing/metrics.
• Reflection can be a security risk when exposed publicly. Prefer enabling only in non‑prod or behind auth.

Observability

• Tracing and metrics are automatically wired via otelgrpc stats handlers. Ensure you call observability.Setup (done by Service.Run) or the helpers in observability/ to export to your backend.
• The component logs a startup line with the port and gracefully stops when the service context is canceled.

Health

A standard gRPC health service is registered by default (grpc.health.v1.Health). You can wire your own health reporting using that API if needed.

Try the example

• Start the example service (includes HTTP, Kafka, etc., but also gRPC):

make example-service

• From the example client, run only the gRPC path:

make example-client

The client calls SayHello on the example Greeter service defined in examples/greeter.proto.