feat: App stats availability measurement

Currently concerned with when stats are seen as unavailable by the
client. Does not include when stats are set to zero by the Cloud
Controller when one or more required metrics are missing.

Co-authored-by: Rebecca Roberts <rebecca.roberts@broadcom.com>

README.md

@@ -13,11 +13,12 @@ It measures:
 - app syslog availability,
   by periodically checking that app logs
   drain to a syslog sink.
+- app stats availability,
+  by periodically checking that app stats
+  are not unavailable.
 
-The CF Release Integration team uses it
-to monitor availability during migrations
-from `cf-release` to `cf-deployment`,
-and during upgrade deployments.
+It is often used to monitor availability
+during upgrade deployments.
 
 ## Installation
 
@@ -66,6 +67,7 @@ Here is an example config `json`:
     "allowed_failures": {
         "app_pushability": 2,
         "http_availability": 5,
+        "app_stats": 2,
         "recent_logs": 2,
         "streaming_logs": 2,
         "app_syslog_availability": 2

cfCmdGenerator/cfCmdGenerator.go

@@ -24,6 +24,7 @@ type CfCmdGenerator interface {
 	DeleteOrg(org string) cmdStartWaiter.CmdStartWaiter
 	DeleteQuota(quota string) cmdStartWaiter.CmdStartWaiter
 	LogOut() cmdStartWaiter.CmdStartWaiter
+	AppStats(appName string) cmdStartWaiter.CmdStartWaiter
 	RecentLogs(appName string) cmdStartWaiter.CmdStartWaiter
 	StreamLogs(ctx context.Context, appName string) cmdStartWaiter.CmdStartWaiter
 	MapRoute(appName, domain string, port int) cmdStartWaiter.CmdStartWaiter
@@ -175,6 +176,14 @@ func (c *cfCmdGenerator) LogOut() cmdStartWaiter.CmdStartWaiter {
 	)
 }
 
+func (c *cfCmdGenerator) AppStats(appName string) cmdStartWaiter.CmdStartWaiter {
+	return c.setCfHome(
+		exec.Command(
+			"cf", "app", appName,
+		),
+	)
+}
+
 func (c *cfCmdGenerator) RecentLogs(appName string) cmdStartWaiter.CmdStartWaiter {
 	return c.setCfHome(
 		exec.Command(

cfCmdGenerator/cfCmdGenerator_test.go

@@ -162,6 +162,14 @@ var _ = Describe("CfCmdGenerator", func() {
 		})
 	})
 
+	Describe("AppStats", func() {
+		It("Generates the correct command", func() {
+			expectedCmd := exec.Command("cf", "app", "appName")
+			cmd := generator.AppStats("appName")
+			expectCommandToBeEquivalent(cmd, expectedCmd, cfHomeEnvVar)
+		})
+	})
+
 	Describe("RecentLogs", func() {
 		It("Generates the correct command", func() {
 			expectedCmd := exec.Command("cf", "logs", "appName", "--recent")

cfWorkflow/cfWorkflow.go

@@ -24,6 +24,7 @@ type CfWorkflow interface {
 	Delete(cfCmdGenerator.CfCmdGenerator) []cmdStartWaiter.CmdStartWaiter
 	TearDown(cfCmdGenerator.CfCmdGenerator) []cmdStartWaiter.CmdStartWaiter
 	RecentLogs(cfCmdGenerator.CfCmdGenerator) []cmdStartWaiter.CmdStartWaiter
+	AppStats(cfCmdGenerator.CfCmdGenerator) []cmdStartWaiter.CmdStartWaiter
 	StreamLogs(context.Context, cfCmdGenerator.CfCmdGenerator) []cmdStartWaiter.CmdStartWaiter
 
 	MapSyslogRoute(cfCmdGenerator.CfCmdGenerator) []cmdStartWaiter.CmdStartWaiter
@@ -141,6 +142,15 @@ func (c *cfWorkflow) TearDown(ccg cfCmdGenerator.CfCmdGenerator) []cmdStartWaite
 	return ret
 }
 
+func (c *cfWorkflow) AppStats(ccg cfCmdGenerator.CfCmdGenerator) []cmdStartWaiter.CmdStartWaiter {
+	return []cmdStartWaiter.CmdStartWaiter{
+		ccg.Api(c.cf.API),
+		ccg.Auth(c.cf.AdminUser, c.cf.AdminPassword),
+		ccg.Target(c.org, c.space),
+		ccg.AppStats(c.appName),
+	}
+}
+
 func (c *cfWorkflow) RecentLogs(ccg cfCmdGenerator.CfCmdGenerator) []cmdStartWaiter.CmdStartWaiter {
 	return []cmdStartWaiter.CmdStartWaiter{
 		ccg.Api(c.cf.API),

cfWorkflow/cfWorkflow_test.go

@@ -213,6 +213,21 @@ var _ = Describe("CfWorkflow", func() {
 		})
 	})
 
+	Describe("AppStats", func() {
+		It("returns a set of commands to get stats for an app", func() {
+			cmds := cw.AppStats(ccg)
+
+			Expect(cmds).To(Equal(
+				[]cmdStartWaiter.CmdStartWaiter{
+					ccg.Api("jigglypuff.cf-app.com"),
+					ccg.Auth("pika", "chu"),
+					ccg.Target("someOrg", "someSpace"),
+					ccg.AppStats("doraApp"),
+				},
+			))
+		})
+	})
+
 	Describe("RecentLogs", func() {
 		It("returns a set of commands to get recent logs for an app", func() {
 			cmds := cw.RecentLogs(ccg)

config/config.go

@@ -36,6 +36,7 @@ type AllowedFailures struct {
 	HttpAvailability      int `json:"http_availability"`
 	RecentLogs            int `json:"recent_logs"`
 	StreamingLogs         int `json:"streaming_logs"`
+	AppStats              int `json:"app_stats"`
 	AppSyslogAvailability int `json:"app_syslog_availability"`
 	TCPAvailability       int `json:"tcp_availability"`
 }