From c1f4faaab375743f94ccc2ff416ed0df46265943 Mon Sep 17 00:00:00 2001
From: Ryan Uber <ru@ryanuber.com>
Date: Tue, 8 Sep 2015 11:51:20 -0700
Subject: [PATCH] api: allow querying node name from agent

---
 api/agent.go      | 22 +++++++++++++++++++++-
 api/agent_test.go | 22 ++++++++++++++++++++++
 2 files changed, 43 insertions(+), 1 deletion(-)

diff --git a/api/agent.go b/api/agent.go
index aeec83e21..e80523c42 100644
--- a/api/agent.go
+++ b/api/agent.go
@@ -8,7 +8,9 @@ import (
 // agent endpoints for a specific node.
 type Agent struct {
 	client *Client
-	node   string
+
+	// Cache static agent info
+	nodeName string
 }
 
 // Agent returns a new agent which can be used to query
@@ -30,3 +32,21 @@ func (a *Agent) Self() (map[string]map[string]interface{}, error) {
 
 	return out, nil
 }
+
+// NodeName is used to query the Nomad agent for its node name.
+func (a *Agent) NodeName() (string, error) {
+	// Return from cache if we have it
+	if a.nodeName != "" {
+		return a.nodeName, nil
+	}
+
+	// Query the node name
+	info, err := a.Self()
+	if err != nil {
+		return "", err
+	}
+	if name, ok := info["member"]["Name"]; ok {
+		a.nodeName = name.(string)
+	}
+	return a.nodeName, nil
+}
diff --git a/api/agent_test.go b/api/agent_test.go
index fd038970d..177db0e87 100644
--- a/api/agent_test.go
+++ b/api/agent_test.go
@@ -22,3 +22,25 @@ func TestAgent_Self(t *testing.T) {
 		t.Fatalf("bad member name in response: %#v", res)
 	}
 }
+
+func TestAgent_NodeName(t *testing.T) {
+	c, s := makeClient(t, nil, nil)
+	defer s.Stop()
+	a := c.Agent()
+
+	// Query the agent for the node name
+	res, err := a.NodeName()
+	if err != nil {
+		t.Fatalf("err: %s", err)
+	}
+
+	// Ensure we got a node name back
+	if res == "" {
+		t.Fatalf("expected node name, got nothing")
+	}
+
+	// Check that we cached the node name
+	if a.nodeName == "" {
+		t.Fatalf("should have cached node name")
+	}
+}