Optional NATS config / event publishing (#31)

* Not all projects will need event publishing, so it should be configurable such that ones that don't intend to use it don't need to have NATS credentials configured for them. Signed-off-by: Jacob See <[email protected]> * Switch from nil pointer to an enabled field on the struct Signed-off-by: Jacob See <[email protected]> --------- Signed-off-by: Jacob See <[email protected]>
infratographer · Mar 14, 2024 · 84f45b7 · 84f45b7
1 parent d6a01fe
commit 84f45b7
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Showing 4 changed files with 24 additions and 2 deletions.
diff --git a/README.md b/README.md
@@ -41,6 +41,7 @@ data:
       jwksuri: https://iam.example.com/jwks.json
       issuer: https://iam.example.com/
     events:
+      enabled: true
       nats:
         url: nats://nats:4222
         credsFile: /etc/nats/nats.creds
@@ -71,7 +72,7 @@ spec:
               - name: iam-runtime-socket
                 mountPath: /var/iam-runtime/
         - name: iam-runtime
-            image: ghcr.io/infratographer/iam-runtime-infratographer:v0.3.0
+            image: ghcr.io/infratographer/iam-runtime-infratographer:v0.3.1
             volumeMounts:
               - name: iam-runtime-config
                 mountPath: /etc/iam-runtime-infratographer/

diff --git a/internal/eventsx/config.go b/internal/eventsx/config.go
@@ -4,7 +4,8 @@ import "github.com/spf13/pflag"
 
 // Config represents a configuration for events.
 type Config struct {
-	NATS NATSConfig `mapstructure:"nats"`
+	Enabled bool       `mapstructure:"enabled"`
+	NATS    NATSConfig `mapstructure:"nats"`
 }
 
 // NATSConfig represents NATS-specific configuration for events.
@@ -18,6 +19,7 @@ type NATSConfig struct {
 
 // AddFlags sets the command line flags for publishing events.
 func AddFlags(flags *pflag.FlagSet) {
+	flags.Bool("events.enabled", false, "enable NATS event-based functions")
 	flags.String("events.nats.url", "", "NATS server URL to use")
 	flags.String("events.nats.publishprefix", "", "NATS publish prefix to use")
 	flags.String("events.nats.publishtopic", "", "NATS publish topic to use")

diff --git a/internal/eventsx/errors.go b/internal/eventsx/errors.go
@@ -0,0 +1,6 @@
+package eventsx
+
+import "errors"
+
+// ErrPublishNotEnabled represents an error state where an event publish was attempted despite not being enabled
+var ErrPublishNotEnabled = errors.New("event publishing is not enabled")
diff --git a/internal/eventsx/publisher.go b/internal/eventsx/publisher.go
@@ -13,16 +13,28 @@ type Publisher interface {
 }
 
 type publisher struct {
+	enabled  bool
 	topic    string
 	innerPub events.AuthRelationshipPublisher
 }
 
 func (p publisher) PublishAuthRelationshipRequest(ctx context.Context, message events.AuthRelationshipRequest) (events.Message[events.AuthRelationshipResponse], error) {
+	if !p.enabled {
+		return nil, ErrPublishNotEnabled
+	}
 	return p.innerPub.PublishAuthRelationshipRequest(ctx, p.topic, message)
 }
 
 // NewPublisher creates a new events publisher from the given config.
 func NewPublisher(cfg Config) (Publisher, error) {
+	if !cfg.Enabled {
+		return publisher{
+			enabled:  false,
+			topic:    "",
+			innerPub: nil,
+		}, nil
+	}
+
 	natsCfg := events.NATSConfig{
 		URL:           cfg.NATS.URL,
 		PublishPrefix: cfg.NATS.PublishPrefix,
@@ -36,6 +48,7 @@ func NewPublisher(cfg Config) (Publisher, error) {
 	}
 
 	out := publisher{
+		enabled:  true,
 		topic:    cfg.NATS.PublishTopic,
 		innerPub: conn,
 	}