Configuration

Requirements: Dapr 1.18+ with mTLS enabled. .NET 10.0 SDK.

Virtufin.API supports configuration via environment variables and command-line arguments. Both methods are supported with consistent behavior across all Virtufin projects.

Precedence

Configuration is loaded in the following order:

1. Environment variables (loaded first)
2. Command-line arguments (loaded second)

Command-line arguments take precedence over environment variables.

Configuration Keys

Port Configuration

Key	Description	Default
HttpPort	HTTP port (REST, Swagger, health, gRPC-Web)	5001
GrpcPort	gRPC port (native gRPC HTTP/2 h2c)	5002
DaprHttpPort	Dapr HTTP port	3500
DaprGrpcPort	Dapr gRPC port	50001

Environment Variables

Set configuration using environment variables:

export HttpPort=5001
export GrpcPort=5002
export DaprHttpPort=3500
export DaprGrpcPort=50001
export DAPR_RETRY_ATTEMPTS=3
export DAPR_RETRY_BASE_DELAY_MS=200
export DAPR_CIRCUIT_BREAKER_THRESHOLD=5
export DAPR_CIRCUIT_BREAKER_DURATION_SECONDS=30

Dapr Resiliency

The DaprResiliencePipeline wraps every Dapr SDK call the API makes, including the Gateway.Invoke and Gateway.InvokeJson gRPC calls to downstream services (WebSocketManager, WorkManager). The pipeline uses Polly: retry with exponential backoff, then circuit breaker. The circuit state is exposed at /health (tag dapr).

Key	Description	Default	Range
DAPR_RETRY_ATTEMPTS	Max retry attempts per Dapr call before the pipeline throws.	3	0–20
DAPR_RETRY_BASE_DELAY_MS	Base delay between attempts; actual delay is RetryBaseDelayMs * 2^attempt.	200	10–60000
DAPR_CIRCUIT_BREAKER_THRESHOLD	Minimum throughput before the circuit can trip (Polly MinimumThroughput).	5	1–1000
DAPR_CIRCUIT_BREAKER_DURATION_SECONDS	How long the circuit stays open before transitioning to half-open.	30	1–3600

The circuit breaker uses Polly's FailureRatio = 0.5 (a 50% failure rate trips the circuit). The above env vars control the other knobs.

Command-Line Arguments

Pass arguments when running the application:

Virtufin.Api --http-port 5001 --grpc-port 5002

Available Arguments

Argument	Description	Default
--http-port <port>	HTTP port (REST, Swagger, health, gRPC-Web)	5001
--grpc-port <port>	gRPC port (native gRPC HTTP/2 h2c)	5002
--dapr-http-port <port>	Dapr HTTP port	3500
--dapr-grpc-port <port>	Dapr gRPC port	50001

Note: The HTTP port serves REST, Swagger, health probes, and gRPC-Web over HTTP/1.1. The gRPC port serves native gRPC over HTTP/2 cleartext (h2c).

Examples

Using Environment Variables

export HttpPort=3000
export GrpcPort=3002
./Virtufin.Api

Using Command-Line Arguments

./Virtufin.Api --http-port 3000 --grpc-port 3002

Combining Both

Environment variables set defaults, command-line arguments override:

export HttpPort=3000
./Virtufin.Api --grpc-port 3002

In this example, HttpPort is 3000 (from environment) and GrpcPort is 3002 (from command line).

CORS Configuration

The API supports CORS configuration via the Cors:AllowedOrigins configuration key:

export Cors:AllowedOrigins__0=https://example.com
export Cors:AllowedOrigins__1=https://app.example.com

Or via appsettings.json:

{
  "Cors": {
    "AllowedOrigins": ["https://example.com", "https://app.example.com"]
  }
}

If no origins are configured, CORS is disabled and all cross-origin requests are rejected.