gRPC

Expose gRPC services (server) or call external gRPC endpoints (client). Uses Protocol Buffers for schema definition and supports TLS, load balancing, and all standard gRPC patterns.

Server Configuration

connector "grpc_api" {
  type   = "grpc"
  driver = "server"
  port   = 50051

  proto_path  = "./proto"
  proto_files = ["service.proto"]
  reflection  = true

  tls {
    cert_file = "/path/to/cert.pem"
    key_file  = "/path/to/key.pem"
  }
}

Client Configuration

connector "grpc_service" {
  type   = "grpc"
  driver = "client"
  target = "localhost:50051"

  proto_path  = "./proto"
  proto_files = ["service.proto"]
}

Common Options

Option	Type	Description
driver	string	server or client
port	int	Listen port (server)
target	string	Target address host:port (client)
proto_path	string	Directory containing .proto files
proto_files	list	Specific .proto files to load
reflection	bool	Enable gRPC reflection (default: true)
insecure	bool	Disable TLS (client, default: false)
tls.cert_file	string	TLS certificate path
tls.key_file	string	TLS key path

Operations

Server (source): RPC method names as defined in the proto file — e.g., GetUser, ListUsers.

Client (target): Same RPC method names, resolved against the target service.

Example

flow "get_user" {
  from {
    connector = "grpc_api"
    operation = "GetUser"
  }

  step "user" {
    connector = "db"
    operation = "query"
    query     = "SELECT * FROM users WHERE id = ?"
    params    = [input.id]
  }

  transform { output = "step.user" }
  to { response }
}

See the grpc example and grpc-loadbalancing example for complete setups.

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Full configuration reference: See gRPC in the Configuration Reference.