feat(deployment): add domain config getter abstraction

Add an Environment-level DomainConfigGetter interface with an os.Getenv-backed implementation, and cover default wiring plus getter behavior with focused deployment tests.

Author: graham-chainlink

deployment/domain_config_getter.go

@@ -0,0 +1,14 @@
+package deployment
+
+import "os"
+
+// DomainConfigGetter retrieves config values by key.
+type DomainConfigGetter interface {
+	Get(key string) (value string, found bool)
+}
+
+type envVarDomainConfigGetter struct{}
+
+func (envVarDomainConfigGetter) Get(key string) (string, bool) {
+	return os.LookupEnv(key)
+}

deployment/domain_config_getter_test.go

@@ -0,0 +1,31 @@
+package deployment
+
+import (
+	"os"
+	"testing"
+
+	"github.com/stretchr/testify/require"
+)
+
+//nolint:paralleltest // Mutates process-global env vars via os.Setenv.
+func TestEnvVarDomainConfigGetter_Get(t *testing.T) {
+	const (
+		key   = "CLDF_TEST_DOMAIN_CONFIG_GETTER_KEY"
+		value = "domain-config-value"
+	)
+
+	prevValue, hadPrevValue := os.LookupEnv(key)
+	require.NoError(t, os.Setenv(key, value))
+	t.Cleanup(func() {
+		if hadPrevValue {
+			_ = os.Setenv(key, prevValue)
+			return
+		}
+		_ = os.Unsetenv(key)
+	})
+
+	var getter DomainConfigGetter = envVarDomainConfigGetter{}
+	got, found := getter.Get(key)
+	require.True(t, found)
+	require.Equal(t, value, got)
+}

deployment/environment.go

@@ -60,6 +60,8 @@ type Environment struct {
 	OperationsBundle operations.Bundle
 	// BlockChains is the container of all chains in the environment.
 	BlockChains chain.BlockChains
+	// DomainConfigGetter is used to read domain-backed configuration values.
+	DomainConfigGetter DomainConfigGetter
 }
 
 // EnvironmentOption is a functional option for configuring an Environment
@@ -88,8 +90,9 @@ func NewEnvironment(
 		GetContext:        ctx,
 		OCRSecrets:        secrets,
 		// default to memory reporter as that is the only reporter available for now
-		OperationsBundle: operations.NewBundle(ctx, logger, operations.NewMemoryReporter()),
-		BlockChains:      blockChains,
+		OperationsBundle:   operations.NewBundle(ctx, logger, operations.NewMemoryReporter()),
+		BlockChains:        blockChains,
+		DomainConfigGetter: envVarDomainConfigGetter{},
 	}
 
 	// Apply functional options
@@ -115,16 +118,17 @@ func (e Environment) Clone() Environment {
 	}
 
 	return Environment{
-		Name:              e.Name,
-		Logger:            e.Logger,
-		ExistingAddresses: ab,
-		DataStore:         ds.Seal(),
-		NodeIDs:           e.NodeIDs,
-		Offchain:          e.Offchain,
-		GetContext:        e.GetContext,
-		OCRSecrets:        e.OCRSecrets,
-		OperationsBundle:  e.OperationsBundle,
-		BlockChains:       e.BlockChains,
+		Name:               e.Name,
+		Logger:             e.Logger,
+		ExistingAddresses:  ab,
+		DataStore:          ds.Seal(),
+		NodeIDs:            e.NodeIDs,
+		Offchain:           e.Offchain,
+		GetContext:         e.GetContext,
+		OCRSecrets:         e.OCRSecrets,
+		OperationsBundle:   e.OperationsBundle,
+		BlockChains:        e.BlockChains,
+		DomainConfigGetter: e.DomainConfigGetter,
 	}
 }
 

deployment/environment_test.go

@@ -0,0 +1,14 @@
+package deployment
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/require"
+)
+
+func TestNewEnvironment_DefaultDomainConfigGetter(t *testing.T) {
+	t.Parallel()
+
+	env := NewNoopEnvironment(t)
+	require.NotNil(t, env.DomainConfigGetter)
+}