规则链

pkg/rule_engine/nodes/external_nats_node.go

@@ -0,0 +1,48 @@
+package nodes
+
+import (
+	"github.com/nats-io/nats.go"
+	"github.com/sirupsen/logrus"
+	"pandax/pkg/rule_engine/message"
+)
+
+type externalNatsNode struct {
+	bareNode
+	Url     string `json:"url"`
+	Subject string `json:"subject"`
+	Body    string
+	client  *nats.Conn
+}
+
+type externalNatsNodeFactory struct{}
+
+func (f externalNatsNodeFactory) Name() string     { return "NatsNode" }
+func (f externalNatsNodeFactory) Category() string { return NODE_CATEGORY_EXTERNAL }
+func (f externalNatsNodeFactory) Labels() []string { return []string{"Success", "Failure"} }
+func (f externalNatsNodeFactory) Create(id string, meta Metadata) (Node, error) {
+	node := &externalNatsNode{
+		bareNode: newBareNode(f.Name(), id, meta, f.Labels()),
+	}
+	_, err := decodePath(meta, node)
+	if err != nil {
+		return node, err
+	}
+	connect, err := nats.Connect(node.Url)
+	if err != nil {
+		return node, err
+	}
+	node.client = connect
+	return node, nil
+}
+
+func (n *externalNatsNode) Handle(msg message.Message) error {
+	logrus.Infof("%s handle message '%s'", n.Name(), msg.GetType())
+	successLabelNode := n.GetLinkedNode("Success")
+	failureLabelNode := n.GetLinkedNode("Failure")
+	err := n.client.Publish(n.Subject, []byte(n.Body))
+	if err != nil {
+		n.client.Close()
+		return failureLabelNode.Handle(msg)
+	}
+	return successLabelNode.Handle(msg)
+}