From c93ba833100e1f903cd245dc8824cb2263f679d2 Mon Sep 17 00:00:00 2001
From: Mitchell Hashimoto <mitchell.hashimoto@gmail.com>
Date: Sat, 19 May 2018 11:04:47 -0700
Subject: [PATCH] command/connect/proxy: tests for configuration

---
 command/connect/proxy/proxy.go      | 30 ++++++++---
 command/connect/proxy/proxy_test.go | 83 +++++++++++++++++++++++++++++
 2 files changed, 106 insertions(+), 7 deletions(-)
 create mode 100644 command/connect/proxy/proxy_test.go

diff --git a/command/connect/proxy/proxy.go b/command/connect/proxy/proxy.go
index fc9e65b860..5d219d3eff 100644
--- a/command/connect/proxy/proxy.go
+++ b/command/connect/proxy/proxy.go
@@ -8,6 +8,7 @@ import (
 	"net/http"
 	_ "net/http/pprof" // Expose pprof if configured
 	"os"
+	"sort"
 
 	proxyAgent "github.com/hashicorp/consul/agent/proxy"
 	"github.com/hashicorp/consul/api"
@@ -44,6 +45,9 @@ type cmd struct {
 	pprofAddr string
 	service   string
 	upstreams map[string]proxyImpl.UpstreamConfig
+
+	// test flags
+	testNoStart bool // don't start the proxy, just exit 0
 }
 
 func (c *cmd) init() {
@@ -86,6 +90,10 @@ func (c *cmd) Run(args []string) int {
 	if err := c.flags.Parse(args); err != nil {
 		return 1
 	}
+	if len(c.flags.Args()) > 0 {
+		c.UI.Error(fmt.Sprintf("Should have no non-flag arguments."))
+		return 1
+	}
 
 	// Load the proxy ID and token from env vars if they're set
 	if c.proxyID == "" {
@@ -147,10 +155,11 @@ func (c *cmd) Run(args []string) int {
 	c.UI.Output("Log data will now stream in as it occurs:\n")
 	logGate.Flush()
 
-	// Run the proxy
-	err = p.Serve()
-	if err != nil {
-		c.UI.Error(fmt.Sprintf("Failed running proxy: %s", err))
+	// Run the proxy unless our tests require we don't
+	if !c.testNoStart {
+		if err := p.Serve(); err != nil {
+			c.UI.Error(fmt.Sprintf("Failed running proxy: %s", err))
+		}
 	}
 
 	c.UI.Output("Consul Connect proxy shutdown")
@@ -179,10 +188,17 @@ func (c *cmd) configWatcher(client *api.Client) (proxyImpl.ConfigWatcher, error)
 				"configure itself.")
 	}
 
-	// Convert our upstreams to a slice of configurations
+	// Convert our upstreams to a slice of configurations. We do this
+	// deterministically by alphabetizing the upstream keys. We do this so
+	// that tests can compare the upstream values.
+	upstreamKeys := make([]string, 0, len(c.upstreams))
+	for k := range c.upstreams {
+		upstreamKeys = append(upstreamKeys, k)
+	}
+	sort.Strings(upstreamKeys)
 	upstreams := make([]proxyImpl.UpstreamConfig, 0, len(c.upstreams))
-	for _, u := range c.upstreams {
-		upstreams = append(upstreams, u)
+	for _, k := range upstreamKeys {
+		upstreams = append(upstreams, c.upstreams[k])
 	}
 
 	return proxyImpl.NewStaticConfigWatcher(&proxyImpl.Config{
diff --git a/command/connect/proxy/proxy_test.go b/command/connect/proxy/proxy_test.go
new file mode 100644
index 0000000000..b99fbfae1b
--- /dev/null
+++ b/command/connect/proxy/proxy_test.go
@@ -0,0 +1,83 @@
+package proxy
+
+import (
+	"testing"
+	"time"
+
+	"github.com/hashicorp/consul/agent"
+	"github.com/hashicorp/consul/connect/proxy"
+	"github.com/mitchellh/cli"
+	"github.com/stretchr/testify/require"
+)
+
+func TestCommandConfigWatcher(t *testing.T) {
+	t.Parallel()
+
+	cases := []struct {
+		Name  string
+		Flags []string
+		Test  func(*testing.T, *proxy.Config)
+	}{
+		{
+			"-service flag only",
+			[]string{"-service", "web"},
+			func(t *testing.T, cfg *proxy.Config) {
+				require.Equal(t, 0, cfg.PublicListener.BindPort)
+				require.Len(t, cfg.Upstreams, 0)
+			},
+		},
+
+		{
+			"-service flag with upstreams",
+			[]string{
+				"-service", "web",
+				"-upstream", "db:1234",
+				"-upstream", "db2:2345",
+			},
+			func(t *testing.T, cfg *proxy.Config) {
+				require.Equal(t, 0, cfg.PublicListener.BindPort)
+				require.Len(t, cfg.Upstreams, 2)
+				require.Equal(t, 1234, cfg.Upstreams[0].LocalBindPort)
+				require.Equal(t, 2345, cfg.Upstreams[1].LocalBindPort)
+			},
+		},
+	}
+
+	for _, tc := range cases {
+		t.Run(tc.Name, func(t *testing.T) {
+			require := require.New(t)
+
+			a := agent.NewTestAgent(t.Name(), ``)
+			defer a.Shutdown()
+			client := a.Client()
+
+			ui := cli.NewMockUi()
+			c := New(ui, make(chan struct{}))
+			c.testNoStart = true
+
+			// Run and purposely fail the command
+			code := c.Run(append([]string{
+				"-http-addr=" + a.HTTPAddr(),
+			}, tc.Flags...))
+			require.Equal(0, code, ui.ErrorWriter.String())
+
+			// Get the configuration watcher
+			cw, err := c.configWatcher(client)
+			require.NoError(err)
+			tc.Test(t, testConfig(t, cw))
+		})
+	}
+}
+
+func testConfig(t *testing.T, cw proxy.ConfigWatcher) *proxy.Config {
+	t.Helper()
+
+	select {
+	case cfg := <-cw.Watch():
+		return cfg
+
+	case <-time.After(1 * time.Second):
+		t.Fatal("no configuration loaded")
+		return nil // satisfy compiler
+	}
+}